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Describe the INSPEcT R package | INSPEcT is a computational tool to infer mRNA synthesis, processing and degradation dynamics from RNA- and 4sU-seq time course experiments. | MOTIVATION: Cellular mRNA levels originate from the combined action of multiple
regulatory processes, which can be recapitulated by the rates of pre-mRNA
synthesis, pre-mRNA processing and mRNA degradation. Recent experimental and
computational advances set the basis to study these intertwined levels of
regulation. Nevertheless, software for the comprehensive quantification of RNA
dynamics is still lacking.
RESULTS: INSPEcT is an R package for the integrative analysis of RNA- and
4sU-seq data to study the dynamics of transcriptional regulation. INSPEcT
provides gene-level quantification of these rates, and a modeling framework to
identify which of these regulatory processes are most likely to explain the
observed mRNA and pre-mRNA concentrations. Software performance is tested on a
synthetic dataset, instrumental to guide the choice of the modeling parameters
and the experimental design.
AVAILABILITY AND IMPLEMENTATION: INSPEcT is submitted to Bioconductor and is
currently available as Supplementary Additional File S1.
CONTACT: [email protected]
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
Which molecule is targeted by Teprotumumab? | Teprotumumab is a human monoclonal antibody that targets IGF-1R. It can be used for treatment of thyroid eye disease. | PURPOSE OF REVIEW: In recent years, immunosuppressive therapy, as an alternative
to corticosteroids, has been proposed as novel agents which target the various
antigens involved in the pathogenesis of Graves' ophthalmopathy. Although the
lack of randomized and controlled studies suggests caution in generalizing
results, some data show interesting results.
RECENT FINDINGS: Potential targets for immune therapy in Graves' ophthalmopathy
are the antigens expressed on the target organ of inflammation, namely the
receptor and the insulin growth factor -1 receptor on fibroblasts, inflammatory
cytokines, and B and T cells. The most promising results are observed with small
thyroid stimulating hormone receptor molecules interacting with the receptor on
thyrocytes and fibroblasts and with the anti-IGF-1 receptor antibody
teprotumumab. A recent open study with tocilizumab, an anti-soluble
interleukin-6 receptor, has shown inactivation of Graves' ophthalmopathy.
Consistent reports on the efficacy of rituximab will have to be confirmed by
randomized controlled trials, which are now in progress.
SUMMARY: Current clinical practice for Graves' ophthalmopathy will greatly
benefit from the availability of immunosuppressors that act as disease-modifying
drugs, as compared to steroids, the current standard treatment for Graves'
ophthalmopathy. Rituximab seems to be a good candidate, as preliminary results
from ongoing randomized trials suggest good efficacy with a relative well
tolerated profile. PURPOSE: Fibrocytes (FC) are bone marrow-derived progenitor cells that are more
abundant and infiltrate the thyroid and orbit in Graves orbitopathy (GO). FCs
express high levels of thyrotropin receptor (TSHR) and insulin-like growth
factor-1 receptor (IGF-1R). These receptors are physically and functionally
associated, but their role in GO pathogenesis is not fully delineated. Treatment
of FCs with thyroid stimulating hormone (TSH) or M22 (activating antibody to
TSHR) induces the production of numerous cytokines, including tumor necrosis
factor α (TNFα). Teprotumumab (TMB) is a human monoclonal IGF-1R blocking
antibody currently in clinical trial for GO and inhibits TSHR-mediated actions
in FCs.
AIM: To characterize the molecular mechanisms underlying TSH-induced TNFα
production by FCs, and the role of IGF-1R blockade by TMB.
DESIGN: FCs from healthy and GD patients were treated with combinations of TSH,
M22, MG132 and AKTi (inhibitors of NF-κB and Akt, respectively), and TMB. TNFα
protein production was measured by Luminex and flow cytometry. Messenger RNA
expression was quantified by real time PCR.
RESULTS: Treatment with TSH/M22 induced TNFα protein and mRNA production by FCs,
both of which were reduced when FCs were pretreated with MG132 and AKTi
(p<0.0001). TMB decreased TSH-induced TNFα protein production in circulating FCs
from mean fluorescent index (MFI) value of 2.92 to 1.91, and mRNA expression in
cultured FCs from 141- to 52-fold expression (p<0.0001). TMB also decreased
M22-induced TNFα protein production from MFI of 1.67 to 1.12, and mRNA
expression from 6- to 3-fold expression (p<0.0001).
CONCLUSION: TSH/M22 stimulates FC production of TNFα mRNA and protein. This
process involves the transcription factor NF-κB and its regulator Akt. Blocking
IGF-1R attenuates TSH/M22-induced TNFα production. This further delineates the
interaction of TSHR and IGF1-R signaling pathways. By modulating the
proinflammatory properties of FCs such as TNFα production, TMB may be a
promising therapeutic agent for GO. The medical treatment of Graves' orbitopathy (GO) is usually reserved to
moderate to severe disease. Steroids have been widely employed and possess
anti-inflammatory activity, but about 20-30% of patients are not responsive and
about 20% present with disease recurrence. Immunosuppressive therapy alternative
to corticosteroids may target the different antigens involved in pathogenic
mechanisms of GO. Some have already been employed in clinical studies and showed
interesting results, although the lack of randomized and controlled trials
suggests caution for their use in clinical practice. Potential targets for
therapy in GO are the TSH receptor and the IGF-1 receptor on the fibroblasts,
inflammatory cytokines, B and T cells. Most promising results are obtained by
interacting with the PIK3/mTORC1 signaling cascades for adipogenesis and the
anti-IGF-1R with the monoclonal antibody teprotumumab. A recent open study has
shown that tocilizumab, an anti-sIL-6R antibody, inactivates GO. Consistent
reports on the efficacy of rituximab have recently been challenged by randomized
controlled trials. Clinical practice will greatly benefit from the use of
disease modifying agents in GO, as compared to steroids, currently standard
treatment for GO. Among these, rituximab may be useful, especially in patients
resistant to steroid or with contraindications to steroids. However, larger
randomized controlled trials are needed for definitive data on the potential
disease-modifying role of rituximab in GO. Direct targeting of the orbital
fibroblast via immunosuppression or nonimmunosuppressive drugs is emerging as a
promising alternative. BACKGROUND: Thyroid-associated ophthalmopathy, a condition commonly associated
with Graves' disease, remains inadequately treated. Current medical therapies,
which primarily consist of glucocorticoids, have limited efficacy and present
safety concerns. Inhibition of the insulin-like growth factor I receptor
(IGF-IR) is a new therapeutic strategy to attenuate the underlying autoimmune
pathogenesis of ophthalmopathy.
METHODS: We conducted a multicenter, double-masked, randomized,
placebo-controlled trial to determine the efficacy and safety of teprotumumab, a
human monoclonal antibody inhibitor of IGF-IR, in patients with active,
moderate-to-severe ophthalmopathy. A total of 88 patients were randomly assigned
to receive placebo or active drug administered intravenously once every 3 weeks
for a total of eight infusions. The primary end point was the response in the
study eye. This response was defined as a reduction of 2 points or more in the
Clinical Activity Score (scores range from 0 to 7, with a score of ≥3 indicating
active thyroid-associated ophthalmopathy) and a reduction of 2 mm or more in
proptosis at week 24. Secondary end points, measured as continuous variables,
included proptosis, the Clinical Activity Score, and results on the Graves'
ophthalmopathy-specific quality-of-life questionnaire. Adverse events were
assessed.
RESULTS: In the intention-to-treat population, 29 of 42 patients who received
teprotumumab (69%), as compared with 9 of 45 patients who received placebo
(20%), had a response at week 24 (P<0.001). Therapeutic effects were rapid; at
week 6, a total of 18 of 42 patients in the teprotumumab group (43%) and 2 of 45
patients in the placebo group (4%) had a response (P<0.001). Differences between
the groups increased at subsequent time points. The only drug-related adverse
event was hyperglycemia in patients with diabetes; this event was controlled by
adjusting medication for diabetes.
CONCLUSIONS: In patients with active ophthalmopathy, teprotumumab was more
effective than placebo in reducing proptosis and the Clinical Activity Score.
(Funded by River Vision Development and others; ClinicalTrials.gov number,
NCT01868997 .). Thyroid-associated ophthalmopathy (TAO) is a vexing and poorly understood
autoimmune process involving the upper face and tissues surrounding the eyes. In
TAO, the orbit can become inflamed and undergo substantial remodeling that is
disfiguring and can lead to loss of vision. There are currently no approved
medical therapies for TAO, the consequence of its uncertain pathogenic nature.
It usually presents as a component of the syndrome known as Graves' disease
where loss of immune tolerance to the thyrotropin receptor (TSHR) results in the
generation of activating antibodies against that protein and hyperthyroidism.
The role for TSHR and these antibodies in the development of TAO is considerably
less well established. We have reported over the past 2 decades evidence that
the insulin-like growth factorI receptor (IGF1R) may also participate in the
pathogenesis of TAO. Activating antibodies against IGF1R have been detected in
patients with GD. The actions of these antibodies initiate signaling in orbital
fibroblasts from patients with the disease. Further, we have identified a
functional and physical interaction between TSHR and IGF1R. Importantly, it
appears that signaling initiated from either receptor can be attenuated by
inhibiting the activity of IGF1R. These findings underpin the rationale for
therapeutically targeting IGF1R in active TAO. A recently completed therapeutic
trial of teprotumumab, a human IGF1R inhibiting antibody, in patients with
moderate to severe, active TAO, indicates the potential effectiveness and safety
of the drug. It is possible that other autoimmune diseases might also benefit
from this treatment strategy. Thyroid-associated ophthalmopathy (TAO) is a complex disease process presumed to
emerge from autoimmunity occurring in the thyroid gland, most frequently in
Graves disease (GD). It is disfiguring and potentially blinding, culminating in
orbital tissue remodeling and disruption of function of structures adjacent to
the eye. There are currently no medical therapies proven capable of altering the
clinical outcome of TAO in randomized, placebo-controlled multicenter trials.
The orbital fibroblast represents the central target for immune reactivity.
Recent identification of fibroblasts that putatively originate in the bone
marrow as monocyte progenitors provides a plausible explanation for why
antigens, the expressions of which were once considered restricted to the
thyroid, are detected in the TAO orbit. These cells, known as fibrocytes,
express relatively high levels of functional TSH receptor (TSHR) through which
they can be activated by TSH and the GD-specific pathogenic antibodies that
underpin thyroid overactivity. Fibrocytes also express insulin-like growth
factor I receptor (IGF-IR) with which TSHR forms a physical and functional
signaling complex. Notably, inhibition of IGF-IR activity results in the
attenuation of signaling initiated at either receptor. Some studies suggest that
IGF-IR-activating antibodies are generated in GD, whereas others refute this
concept. These observations served as the rationale for implementing a recently
completed therapeutic trial of teprotumumab, a monoclonal inhibitory antibody
targeting IGF-IR in TAO. Results of that trial in active, moderate to severe
disease revealed dramatic and rapid reductions in disease activity and severity.
The targeting of IGF-IR with specific biologic agents may represent a paradigm
shift in the therapy of TAO. Thyroid eye disease is a disabling autoimmune disease associated with orbital
inflammation and tissue remodeling which can result in significant proptosis,
leading to visual alterations and is potentially sight threatening. Current
evidence indicates that autoantibodies to the insulin-like growth factor 1
receptor (IGF-1R), along with the thyroid-stimulating hormone receptor (TSHR),
mediate the pathogenesis in susceptible individuals. Teprotumumab, a monoclonal
IGF-1R antagonist, has demonstrated previously in a 24 week, randomized,
controlled trial to produce significant changes in composite outcomes of
proptosis and clinical activity score as compared with placebo. Further
examination of the proptosis results reported here, indicate that the proptosis
outcome (≥ 2 mm reduction) was met in 71.4% of the teprotumumab-treated patients
as compared with 20% of the placebo-treated patients (p < 0.001). Additionally,
the proptosis benefit was observed early in the trial (study week 6), and all
individual patients demonstrated some benefit at week 24. Improvement was noted
among smokers, non-smokers, men and women, and particularly those with higher
levels of proptosis at baseline. The level of proptosis reduction with
teprotumumab reported here is similar to that seen with decompression surgery.
If these results are confirmed in the ongoing Phase 3 trial, teprotumumab will
offer an alternative to surgery and its associated complications. PURPOSE OF REVIEW: Thyroid eye disease is a complex autoimmune disorder which
causes substantial morbidity. It can result in orbital disfigurement, double
vision, and visual loss. Consequently, it has a substantial negative effect on
quality of life, mental health, and socioeconomic status. Most signs and
symptoms of thyroid eye disease (TED) can be explained by the expansion of the
orbital contents. Steroids are the mainstay of treatment in TED. However,
recurrence may occur once steroids are withdrawn. Furthermore, in most cases,
normal orbital anatomy is not restored, and skilled rehabilitative surgery is
required to reduce disfigurement, double vision, and to preserve vision.
Therefore, novel, causal, and more efficacious treatment strategies are
warranted.
RECENT FINDINGS: In the last decade, the pathophysiology of TED has also been
revised with the identification of new potential therapeutic targets. Recent
clinical trials have shown that considerable benefit may be derived from the
addition of antiproliferative agents (e.g., mycophenolate sodium) in preventing
deterioration after steroid cessation. In addition, targeted biologic therapies
have shown promise, including teprotumumab (anti-IGFR) which appears to
substantially reduce proptosis, rituximab (anti-CD20) which reduces inflammation
and tocilizumab (anti-IL-6) which potentially benefits both of these parameters.
SUMMARY: This short review summarizes the recent research developments in this
area. PURPOSE: Improved understanding of thyroid eye disease (TED) pathogenesis has
facilitated identification of a targeted molecular approach for TED treatment
offering the potential to halt or slow disease progression in a nonsurgical
manner. Herein, we provide a summary of the current knowledge of TED management,
followed by discussion of a novel insulin-like growth factor-1 receptor (IGF-1R)
antagonist antibody and its potential to change the course of the disease.
DESIGN: Perspective.
METHODS: Review of the literature and authors' experience.
RESULTS: Many publications demonstrate IGF-1R overexpression in TED, and its
activation as an autoantigen as a critical factor in TED pathogenesis. Several
in vitro studies demonstrate that IGF-1R inhibition attenuates downstream
molecular events including cytokine and hyaluro production, and cellular
differentiation. These observations led to the hypothesis that blocking IGF-1R
may abrogate the clinical progression of TED. The recent completion of phase 2
and 3 randomized, placebo-controlled trials demonstrate the efficacy and safety
of teprotumumab, a fully human monoclonal IGF-1R antagonist antibody, in
patients with moderate-to-severe, active TED. Both the phase 2 and the recent
phase 3 study results demonstrate that more patients with active TED receiving
teprotumumab experienced a meaningful improvement in proptosis.
CONCLUSIONS: Current TED treatment strategies target inflammation and symptoms,
but do not modify the disease course. Therefore, proptosis as well as strabismus
and its resulting diplopia often remain, impacting patient well-being and
quality of life over the long term. Targeted molecular therapy using
teprotumumab demonstrates disease-modifying benefits with the potential to shift
the paradigm for TED treatment. Thyroid-associated ophthalmopathy (TAO) is an autoimmune component of Graves'
disease for which no currently available medical therapy provides reliable and
safe benefit. Based on insights generated experimentally over the past several
decades, the insulin-like growth factor-I receptor (IGF-IR) has been implicated
in the pathogenesis of TAO. Furthermore, an IGF-IR inhibitor, teprotumumab, has
emerged from 2 clinical trials as a promising treatment for active, moderate to
severe TAO. This brief review intends to provide an overview of the rationale
underlying the development of teprotumumab for this disease. It is possible that
teprotumumab will soon take its place in our therapeutic armamentarium for
active TAO. Author information:
(1)Department of Clinical and Experimental Medicine, University of Pisa, Pisa,
Italy. Electronic address: [email protected].
(2)Department of Translational Research and of New Technologies in Medicine and
Surgery, University of Pisa, 56126, Pisa, Italy. Electronic address:
[email protected].
(3)Department of Clinical and Experimental Medicine, University of Pisa, Pisa,
Italy. Electronic address: [email protected].
(4)Department of Clinical and Experimental Medicine, University of Pisa, Pisa,
Italy. Electronic address: [email protected].
(5)Department of Clinical and Experimental Medicine, University of Pisa, Pisa,
Italy. Electronic address: [email protected].
(6)Department of Clinical and Experimental Medicine, University of Pisa, Pisa,
Italy. Electronic address: [email protected].
(7)Department of Clinical and Experimental Medicine, University of Pisa, Pisa,
Italy. Electronic address: [email protected].
(8)Department of Clinical and Experimental Medicine, University of Pisa, Pisa,
Italy. Electronic address: [email protected].
(9)Department of Clinical and Experimental Medicine, University of Pisa, Pisa,
Italy. Electronic address: [email protected].
(10)Sapienza University of Rome, 9311, Medicosurgical Sciences and
Biotechnologies, C.so della Repubblica 79, Latina, 04100, Italy. Electronic
address: [email protected].
(11)Sapienza University of Rome, 9311, Medicosurgical Sciences and
Biotechnologies, C.so della Repubblica 79, Latina, 04100, Italy; ASL Latina,
217138, Endocrinology Unit, Latina, Lazio, Italy. Electronic address:
[email protected].
(12)Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center,
Tel-Hashomer, Israel; Sackler Faculty of Medicine, Tel-Aviv University,
Tel-Aviv, Israel; I.M. Sechenov First Moscow State Medical University of the
Ministry of Health of the Russian Federation (Sechenov University), Russia.
Electronic address: [email protected].
(13)Department of Clinical and Experimental Medicine, University of Pisa, Pisa,
Italy. Electronic address: [email protected]. Teprotumumab (teprotumumab-trbw; TEPEZZA™ - Horizon Therapeutics) is a
monoclonal antibody insulin-like growth factor-I receptor (IGF-IR) antagonist
developed for the treatment of thyroid eye disease (Graves
ophthalmopathy/orbitopathy, thyroid-associated ophthalmopathy). Based on
positive results from two multinational clinical trials teprotumumab was
recently approved for this indication in the US. This article summarizes the
milestones in the development of teprotumumab leading to this first approval for
thyroid eye disease. INTRODUCTION: Thyroid-associated ophthalmopathy (TAO) is a disfiguring,
potentially blinding, and sub-optimally managed autoimmune condition. Current
therapy of active TAO consists most frequently of glucocorticoid steroids,
orbital radiation, or B-cell depletion; all of which are associated with
substantial side effects. Teprotumumab (Tepezza) is a human monoclonal antibody
against the insulin-like growth factor type I receptor (IGF-IR), recently
evaluated in two clinical trials for active moderate-to-severe TAO that was
recently approved by the United States Food and Drug Administration (FDA) for
use in TAO.
AREAS COVERED: This article reviews phase II and III placebo-controlled,
double-masked, prospective, multicenter studies assessing the efficacy and
safety of teprotumumab for the treatment of active, moderate-to-severe TAO.
EXPERT OPINION: Teprotumumab has demonstrated substantial and rapid improvement
in Clinical Activity Score and proptosis reduction in TAO compared to placebo.
Subjective diplopia and quality of life were also improved in both clinical
trials. Teprotumumab exhibited a favorable safety profile, with transient
hyperglycemia, muscle cramps, and auditory side effects being associated with
the drug; these were usually transient. The trial findings indicate that
teprotumumab is a promising, potential first-line therapy for treating TAO. INTRODUCTION: Thyroid eye disease is a debilitating, disfiguring, and
potentially blinding periocular condition. Teprotumumab is a human insulin-like
growth factor-I receptor monoclonal inhibitor antibody which indicated for
treating thyroid eye disease.
AREAS COVERED: The authors performed a systematic review of the literature using
the PubMed database, and the following keywords were used: 'teprotumumab,'
'thyroid eye disease,' and 'insulin-like growth factor I receptor.' The chemical
property, mechanism of action, pharmacokinetics, clinical efficacy, and safety
of teprotumumab were introduced in this paper.
EXPERT OPINION: Teprotumumab is a human monoclonal antibody targeting
insulin-like growth factor-I receptor. Clinical trials indicated that proptosis
response of teprotumumab was 83%, and clinical activity score, diplopia, and
quality of life were also better than placebo. Teprotumumab was well tolerated,
common adverse reactions included muscle spasm, nausea, alopecia, diarrhea,
fatigue, hyperglycemia, hearing impairment, dysgeusia, headache, and dry skin. Adult respiratory distress syndrome (ARDS) is the leading cause of death
associated with SARS-CoV-2 infection and COVID-19. IGF-1 has been implicated in
ARDS, yet its role in relation to COVID-19-related lung injury has not been
investigated. We hypothesize that blockage of the IGF-1 receptor (IGF-1R)
mitigates lung injury and decreases the risk of death in patients
COVID-19-related ARDS. Patients with fibroproliferative ARDS have been shown to
have increased IGF-1 and IGF-1R staining in lung tissue specimens. Rising levels
of IGF-1 in bronchioalveolar fluid (BAL) and increased IGF-1 mRNA expression in
lung tissues (but declining serum IGF-1 levels) have been found in late stage
ARDS compared with early lung injury. Blockage of IGF-1R decreases lung tissue
damage and increases survival in bleomycin-induced as well as H1N1
influenza-related lung injury in animal models. Teprotumumab is a monoclonal
antibody directed against the IGF-1R that was FDA-approved in 2020 for the
treatment of Graves' orbitopathy. In order to determine if teprotumumab may
reduce lung injury and death related to ARDS in the setting of COVID-19,
preliminary clinical data is needed. IGF-1 levels in serum and BAL fluid must be
measured in patients with COVID-19-related ARDS. Histopathology from lung
samples from patients with COVID-19-related ARDS must be examined for increased
expression of the IGF-1R. Once these are ascertained, and if the data support
IGF-1 involvement, a randomized, placebo-controlled phase 2A trial of
teprotumumab therapy in the setting of COVID-19-related ARDS and
non-COVID-19-related ARDS designed to generate initial data on short-term
efficacy, safety, dosing and administration should be performed. PURPOSE: Teprotumumab, a blocking antibody to the insulin like growth factor 1
receptor (IGF-1R) has been shown to significantly reduce proptosis in recent
phase 2 and 3 trials in patients with inflammatory thyroid eye disease (TED).
Herein, we investigate the impact of teprotumumab on patients with
non-inflammatory TED. We also investigate the expression of the IGF-1R on
orbital tissues from patients with inflammatory and non-inflammatory TED
compared to controls.
METHODS: Consecutive patients with non-inflammatory TED (clinical activity
score, CAS ≤ 1, for at least 4 months, were treated with teprotumumab. They
received a complete course (total eight infusions) of teprotumumab (10 mg/kg for
the first infusion and 20 mg/kg for subsequent infusions every 3 weeks). The
primary outcome was a proptosis response at week 24. Further, IGF-1R α and β
expression was evaluated on orbital tissue from patients with inflammatory and
non-inflammatory TED, as well as healthy controls. Non-biased histological
analysis of IGF-1R expression was performed using ImageJ.
RESULTS: Four patients met eligibility criteria for the clinical study, with a
mean (SD) CAS of 0 (0). Following teprotumumab treatment, there was a mean (SD)
reduction in proptosis of 2.6 mm (1.2). Five patients were included for each
group of the histological study; inflammatory TED, non-inflammatory TED and
controls. IGF-1Rα and IGF-1Rβ expression was significantly greater in the
orbital tissues of patients with inflammatory TED and non-inflammatory TED, when
compared to controls.
CONCLUSION: Our findings demonstrate for the first time, that teprotumumab, a
blocking antibody to the IGF-1R reduces proptosis in a series of patients with
non-inflammatory TED. Overexpression of the IGF-1R in orbital tissue from
patients with non-inflammatory disease compared to controls may be an important
consideration for effect. BACKGROUND: Thyroid eye disease (TED) is characterized by orbital inflammation
and complicated by extraocular muscle fibrosis. Treatment with
rapamycin/sirolimus has been reported to improve ocular motility and disease
manifestations in TED. Whether this resulted from a primary antifibrotic effect
on fibroblasts or was secondary to immune-suppression is unclear.
METHODS: In vitro contractility studies of primary orbital fibroblasts. Cells
from patients with TED and controls were treated with rapamycin [mechanistic
target of rapamycin an (mTOR) inhibitor] and MHY1485 (an mTOR stimulator) as
well as inhibitors upstream in the same signaling cascade (saracatinib and
befatinib).
RESULTS: At concentrations consistent with the therapeutic dosing range in
humans, rapamycin/sirolimus significantly reduces fibrosis in orbital
fibroblasts from TED patients and controls in vitro. This effect is separate
from, and in addition to, its immune suppressive effect. mTOR-driven fibrotic
activity is greater in TED-derived fibroblasts and can be blocked also upstream
of mTOR by inhibition of src. There was no adverse effect on cell survival.
CONCLUSION: The authors present evidence for a direct antifibrotic effect of
rapamycin/sirolimus in primary orbital fibroblasts. Targeting mTOR signaling
presents a further and adjunctive treatment of TED alongside other
immune-suppressive agents. By acting downstream of IGF1-R, sirolimus may offer a
cost-effective alternative to teprotumumab therapy. Clinical case reports, now
supplemented by this in vitro evidence, support the initiation of a clinical
trial to treat the fibrotic sequelae of TED with this already-approved agent.
Such an "off-the-shelf" therapy is a welcome prospect for TED treatment,
particularly one available at a low price. |
Which protein is encoded by the protein APOBEC3C? | The gene APOBEC3C codes for: apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3C | Gastric cancer is one of the leading causes of cancer-associated mortality
worldwide. Cytotoxin‑associated gene A (CagA) has been reported to be associated
with gastric diseases. Phosphatase and tensin homolog (PTEN) and tet
methylcytosine dioxygenase 1 (Tet1) are important tumor‑suppressor genes. The
present study aimed to investigate the underlying functions of CagA in human
gastric cancer, and to explore the associations between CagA, PTEN and Tet1 in
gastric cancer. For that purpose, CagA overexpression and Tet1 interference
recombit lentiviral plasmids were constructed. Quantitative polymerase chain
reaction (qPCR) was utilized to screen gene expression in HGC‑27 human gastric
cancer cells overexpressing CagA. qPCR and western blotting were used to detect
gene and protein expression, respectively. In addition, the methylation status
of PTEN was detected by methylation‑specific PCR. The expression levels of PTEN,
Tet1, apolipoprotein B mRNA editing enzyme catalytic subunit (APOBEC)3A,
APOBEC3C and APOBEC3F were significantly decreased in the CagA overexpression
group compared with in the negative control group in HGC‑27 cells. Compared with
in the negative control group, the mRNA and protein expression levels of PTEN
were markedly decreased in cells with Tet1 interference. The decreased
expression of PTEN was associated with increased methylation levels in the
cells. In addition, the protein expression levels of PTEN were significantly
decreased in HGC‑27 cells when CagA was overexpressed. The expression levels of
PTEN and Tet1 were also markedly decreased in CagA+ gastric cancer tissues
compared with in non‑cancerous tissues. The decreased expression of PTEN in
CagA+ gastric cancer tissues was associated with increased methylation levels.
In conclusion, overexpression of CagA significantly decreased the expression of
PTEN, Tet1, APOBEC3A, APOBEC3C and APOBEC3F in human gastric cancer. In
addition, CagA increased DNA methylation and decreased PTEN expression, which
was reversed by Tet1 overexpression. The present study may facilitate future
therapeutic approaches targeting human gastric cancer. Insect-borne flaviviruses produce a 300-500-base long noncoding RNA, termed
subgenomic flavivirus RNA (sfRNA), by stalling the cellular
5'-3'-exoribonuclease 1 (XRN1) via structures located in their 3' UTRs. In this
study, we demonstrate that sfRNA production by Zika virus represses XRN1
analogous to what we have previously shown for other flaviviruses. Using
protein-RNA reconstitution and a stringent RNA pulldown assay with human
choriocarcinoma (JAR) cells, we demonstrate that the sfRNAs from both dengue
type 2 and Zika viruses interact with a common set of 21 RNA-binding proteins
that contribute to the regulation of post-transcriptional processes in the cell,
including splicing, RNA stability, and translation. We found that four of these
sfRNA-interacting host proteins, DEAD-box helicase 6 (DDX6) and enhancer of mRNA
decapping 3 (EDC3) (two RNA decay factors), phosphorylated adaptor for RNA
export (a regulator of the biogenesis of the splicing machinery), and
apolipoprotein B mRNA-editing enzyme catalytic subunit 3C (APOBEC3C, a nucleic
acid-editing deaminase), inherently restrict Zika virus infection. Furthermore,
we demonstrate that the regulations of cellular mRNA decay and RNA splicing are
compromised by Zika virus infection as well as by sfRNA alone. Collectively,
these results reveal the large extent to which Zika virus-derived sfRNAs
interact with cellular RNA-binding proteins and highlight the potential for
widespread dysregulation of post-transcriptional control that likely limits the
effective response of these cells to viral infection. The artemisinin class of anticancer compounds is well known for oxidative
DNA-damage-mediated growth arrest, followed by cell death. However, the nature
of this genotoxic stress for cancer therapeutics remains elusive. Here we show
that artesunate (Art), a water-soluble artemisinin analog, triggers inducible
anticancer responses directly implicated in the DNA-damage-intended therapy. We
observed that the level of the antiviral enzyme APOBEC3C (apolipoprotein-B
mRNA-editing catalytic polypeptide-like 3C (A3C)) preferentially increased upon
the treatment with Art against tumor xenografts of p53-deficient H1299 cells.
Using gain-of-function experiments, A3C could improve the therapeutic efficacy
of Art, as determined by cell proliferation and colony formation assays.
Furthermore, elevated A3C provoked a minor accumulation of γH2AX foci and the
phosphorylation of RPA32 and Chk1, which strongly sensitized H1299 cells to Art.
The employment of A3C also caused an increase in the synergistic interaction
between Art and Chk1 inhibition. Besides, A3C overexpression delayed the cell
cycle at the S phase, accompanied by attenuated G2/M arrest in the presence of
Art. The enzymatic inactivation of A3C by the mutation of zinc-coordinating
residues (C97S and C100S) indicated that A3C sensitized Art in a
deaminase-dependent manner. Furthermore, we showed that using small interfering
RNA against A3C can induce the chemoresistance of Art. These studies combine to
suggest that upregulated A3C is involved in the Art-induced DNA damage response
as a consequent event to improve the overall cytotoxic responses of Art. Allogeneic hematopoietic stem cell transplants can lead to dramatic reductions
in human immunodeficiency virus (HIV) reservoirs. This effect is partially
mediated by donor T cells recognizing lymphocyte-expressed minor
histocompatibility antigens (mHAgs). The potential to mark maligt and
latently infected cells for destruction makes mHAgs attractive targets for
cellular immunotherapies. However, testing such HIV reservoir reduction
strategies will likely require preclinical studies in non-human primates (NHPs).
In this study, we used a combination of alloimmunization, whole exome
sequencing, and bioinformatics to identify an mHAg in Mauritian cynomolgus
macaques (MCMs). We mapped the minimal optimal epitope to a 10-mer peptide
(SW10) in apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3C
(APOBEC3C) and determined the major histocompatibility complex class I
restriction element as Mafa-A1∗063, which is expressed in almost 90% of MCMs.
APOBEC3C SW10-specific CD8+ T cells recognized immortalized B cells but not
fibroblasts from an mHAg-positive MCM. These results provide a framework for
identifying mHAgs in a non-transplant setting and suggest that APOBEC3C SW10
could be used as a model antigen to test mHAg-targeted therapies in NHPs. |
Does AZD3759 cross the blood brain barrier? | AZD3759 is a novel EGFR tyrosine kinase inhibitor with high capability to penetrate the blood-brain barrier. | Since the discovery of sensitizing EGFR mutations as a predictive marker of
sensitivity to EGFR tyrosine kinase inhibitors (TKIs), the field of targeted
therapy in non-small cell lung cancer (NSCLC) has been revolutionized. Patients
harbouring these sensitizing mutations treated with EGFR TKI have derived
significant clinical outcome when compared with standard platinum based
chemotherapy doublets. However disease progression invariably occurs at a median
of about 9-13 months from initiation treatment, if acquired resistance commonly
due to the development of EGFR T790M mutation. A novel class of "third
generation" EGFR TKIs have been developed that is sensitising and T790M
mutant-specific whilst sparing WT EGFR, representing a significant breakthrough
in the treatment in NSCLC patients with acquired resistance harboring these
genotypes. Early phase clinical data suggest the third generation EGFR TKIs such
as osimertinib, rociletinib, and HM61713 are highly efficacious and well
tolerated. Another promising class of EGFR TKI such as AZD3759 has been designed
to penetrate blood brain barrier to treat brain metastases and leptomeningeal
disease and has showed promising responses in patients with brain metastases.
Acquired resistance to third generation EGFR TKIs has been reported including
EGFR C797S. Given its non-invasive nature, plasma ctDNA is being explored as a
possible approach to detect T790M mutation and to also inform on novel molecular
mechansims of tertiary resistance to third generation EGFR TKIs. An
understanding of the mechanisms of acquired resistance to the third-generation
EGFR TKIs will greatly aid in the development of the next generation of EGFR
TKIs. Non-small-cell lung cancer patients with activating mutations in epidermal
growth factor receptor (EGFR) respond to EGFR tyrosine kinase inhibitor (TKI)
treatment. Nevertheless, patients often develop central nervous system (CNS)
metastases during treatment, even when their extracranial tumors are still under
control. In the absence of effective options, much higher doses of EGFR TKIs
have been attempted clinically, with the goal of achieving high enough drug
concentrations within the CNS. Although limited tumor responses have been
observed with this approach, the toxicities outside the CNS have been too high
to tolerate. We report the discovery and early clinical development of AZD3759,
a selective EGFR inhibitor that can fully penetrate the blood-brain barrier
(BBB), with equal free concentrations in the blood, cerebrospinal fluid, and
brain tissue. Treatment with AZD3759 causes tumor regression in subcutaneous
xenograft, leptomeningeal metastasis (LM), and brain metastasis (BM) lung cancer
models and prevents the development of BM in nude mice. An early clinical study
in patients with BM and LM treated with AZD3759 confirms its BBB-penetrant
properties and antitumor activities. Our data demonstrate the potential of
AZD3759 for the treatment of BM and LM and support its further clinical
evaluation in larger trials. With the use of EGFR TKIs, patient survival is now prolonged and as a
consequence, a higher chance of development of CNS metastases has been observed
during the course of the disease. CNS metastases remains a therapeutically
challenging subset of patient to treat owing to the blood-brain barrier (BBB).
Prior to routine EGFR mutation testing, surgical resection, stereotactic
radiosurgery and/or whole brain radiation therapy (WBRT) were the main treatment
options whereas treatment options for patients with leptomeningeal metastases
(LM) included intra-thecal chemotherapy, WBRT, and ventriculo-peritoneal
shunting. Unfortunately outcome for both BM and LM remains poor with median
survival between 3 and 6 months. Systemic treatment with EGFR TKIs had been
effective in the treatment of intracranial metastases but efficacy of early
generation TKIs were hampered by its limited BBB penetration. The next
generation EGFR TKIs osimertinib and AZD3759 have improved BBB penetration and
the BLOOM study of osimertinib and AZD3759 has reported highly promising
intracranial efficacy and may herald a new frontier to treat this
therapeutically challenging subset of advanced EGFR mutant patients. BACKGROUND: CNS metastases-including brain and leptomeningeal metastases-from
epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer
(NSCLC) are associated with poor prognosis. AZD3759 is a novel EGFR tyrosine
kinase inhibitor with high capability to penetrate the blood-brain barrier. We
aimed to assess the safety, tolerability, pharmacokinetics, and efficacy of
AZD3759 in patients with EGFR-mutant NSCLC with brain and leptomeningeal
metastases.
METHODS: This open-label, multicentre, phase 1 study was undertaken at 11
centres and hospitals in Australia, South Korea, Taiwan, and the USA. Eligible
patients included those with histologically confirmed, advanced-stage,
EGFR-mutant NSCLC. The study was done in two parts, with dose-escalation and
dose-expansion phases. In the dose-escalation phase, patients who had progressed
after treatment with an EGFR tyrosine kinase inhibitor received AZD3759 at 50
mg, 100 mg, 200 mg, 300 mg, or 500 mg twice a day. In the dose-expansion phase,
AZD3759 at 200 mg or 300 mg twice a day was administered to patients with either
brain or leptomeningeal metastases who had never received an EGFR tyrosine
kinase inhibitor and patients with leptomeningeal metastases who had been
pretreated with an EGFR tyrosine kinase inhibitor. The primary objective was
safety and tolerability, with severity of adverse events assessed with the
National Cancer Institute's Common Terminology Criteria for Adverse Events,
version 4.03. This trial is registered with ClinicalTrials.gov, number
NCT02228369.
FINDINGS: Between Nov 18, 2014, and Sept 7, 2016, 67 patients with NSCLC were
enrolled into the study, 29 to the dose-escalation phase and 38 to the
dose-expansion phase. At data cutoff (Dec 12, 2016), three (10%) patients in the
dose-escalation phase and 20 (53%) in the dose-expansion phase were still
receiving treatment. Dose-limiting toxic effects occurred in two (67%) of three
patients who received 500 mg twice a day in the dose-escalation phase (grade 3
acne [n=1] and intolerable grade 2 mucosal inflammation [n=1]); hence, doses of
200 mg and 300 mg twice a day were selected for further assessment in the
dose-expansion phase. Drug-related skin and gastrointestinal disorders of any
grade occurred in 35 (92%) and 29 (76%) patients in the dose-expansion phase,
respectively, and led to treatment discontinuation in one (4%) patient treated
with 200 mg twice a day (grade 3 increase of alanine aminotransferase and
aspartate aminotransferase) and two (13%) patients given 300 mg twice a day
(grade 3 diarrhoea [n=1] and grade 3 skin rash [n=1]). Grade 3 skin and
gastrointestinal disorders occurred in four (17%) and two (9%) patients,
respectively, at a dose of 200 mg twice a day, and in six (40%) and four (27%)
patients, respectively, at a dose of 300 mg twice a day. No grade 4 disorders
arose. Other grade 3 disorders included hepatobiliary and renal disorders (three
[13%] at 200 mg twice a day), asthenia (one [7%] at 300 mg twice a day),
infections and infestations (one [7%] at 300 mg twice a day), and metabolism and
nutrition disorders (one [4%] at 200 mg twice a day and one [7%] at 300 mg twice
a day).
INTERPRETATION: AZD3759 at a dose of 200 mg twice daily showed a tolerable
safety profile in patients with NSCLC and CNS metastases who had either never
received a tyrosine kinase inhibitor or who had been pretreated with a tyrosine
kinase inhibitor. The good penetration of the blood-brain barrier by AZD3759,
and its promising clinical activity, support further assessment of this compound
in studies.
FUNDING: AstraZeneca. The prognosis of patients with brain metastasis (BM) is poor. In our study, we
demonstrated that AZD3759, an EGFR tyrosine kinase inhibitors (TKIs) with
excellent blood-brain barrier (BBB) penetration, combined with radiation
enhanced the antitumor efficacy in BM model from EGFR mutant (EGFRm) NSCLC.
Besides, the antitumor activity displayed no difference between radiation
concurrently with AZD3759 and radiation sequentially with AZD3759.
Mechanistically, we found that two factors determined the enhanced efficacy:
cells with EGFRm which were sensitive to AZD3759, and a relative high
concentration of AZD3759. We have validated mechanisms underlying the
radiosensitizing effect of AZD3759, which were involved in decreased cell
proliferation and survival, and suppressed repair of DNA damage. Moreover, our
study found that AZD3759 inhibited both the non-homologous end joining (NHEJ)
and homologous recombination (HR) DNA double-strand breaks (DSBs) repair
pathway, and abrogated the G2/M checkpoint to suppress DNA damage repair. We
also detected the BBB penetration of AZD3759 when combined with cranial
radiation. The results showed the BBB penetration of AZD3759 was decreased
within 24 hr after radiation, however, the free concentration of AZD3759 in
brain kept at a high level in the context of radiation. In conclusion, our
findings suggest that AZD3759 combined with radiation enhances the antitumor
activity in BM from EGFRm NSCLC, this combination therapy may be an effective
treatment option for BM from EGFRm NSCLC. |
What is the major sequence determinant for nucleosome positioning? | G+C content is the primary determinant of MNase-derived nucleosome occupancy. | We assess the role of intrinsic histone-DNA interactions by mapping nucleosomes
assembled in vitro on genomic DNA. Nucleosomes strongly prefer yeast DNA over
Escherichia coli DNA, indicating that the yeast genome evolved to favor
nucleosome formation. Many yeast promoter and terminator regions intrinsically
disfavor nucleosome formation, and nucleosomes assembled in vitro show strong
rotational positioning. Nucleosome arrays generated by the ACF assembly factor
have fewer nucleosome-free regions, reduced rotational positioning and less
translational positioning than obtained by intrinsic histone-DNA interactions.
Notably, nucleosomes assembled in vitro have only a limited preference for
specific translational positions and do not show the pattern observed in vivo.
Our results argue against a genomic code for nucleosome positioning, and they
suggest that the nucleosomal pattern in coding regions arises primarily from
statistical positioning from a barrier near the promoter that involves some
aspect of transcriptional initiation by RNA polymerase II. Recent studies of genome-wide nucleosomal organization suggest that the DNA
sequence is one of the major determits of nucleosome positioning. Although
the search for underlying patterns encoded in nucleosomal DNA has been going on
for about 30 years, our knowledge of these patterns still remains limited. Based
on our evaluations of DNA deformation energy, we developed new scoring functions
to predict nucleosome positioning. There are three principal differences between
our approach and earlier studies: (i) we assume that the length of nucleosomal
DNA varies from 146 to 147 bp; (ii) we consider the anisotropic flexibility of
pyrimidine-purine (YR) dimeric steps in the context of their neighbors (e.g.,
YYRR versus RYRY); (iii) we postulate that alternating AT-rich and GC-rich
motifs reflect sequence-dependent interactions between histone arginines and DNA
in the minor groove. Using these functions, we analyzed 20 nucleosome positions
mapped in vitro at single nucleotide resolution (including clones 601, 603, 605,
the pGUB plasmid, chicken beta-globin and three 5S rDNA genes). We predicted 15
of the 20 positions with 1-bp precision, and two positions with 2-bp precision.
The predicted position of the '601' nucleosome (i.e., the optimum of the
computed score) deviates from the experimentally determined unique position by
no more than 1 bp - an accuracy exceeding that of earlier predictions. Our
analysis reveals a clear heterogeneity of the nucleosomal sequences which can be
divided into two groups based on the positioning 'rules' they follow. The
sequences of one group are enriched by highly deformable YR/YYRR motifs at the
minor-groove bending sites SHL+/- 3.5 and +/- 5.5, which is similar to the
alpha-satellite sequence used in most crystallized nucleosomes. Apparently, the
positioning of these nucleosomes is determined by the interactions between
histones H2A/H2B and the terminal parts of nucleosomal DNA. In the other group
(that includes the '601' clone) the same YR/YYRR motifs occur predomitly at
the sites SHL +/- 1.5. The interaction between the H3/H4 tetramer and the
central part of the nucleosomal DNA is likely to be responsible for the
positioning of nucleosomes of this group, and the DNA trajectory in these
nucleosomes may differ in detail from the published structures. Thus, from the
stereochemical perspective, the in vitro nucleosomes studied here follow either
an X-ray-like pattern (with strong deformations in the terminal parts of
nucleosomal DNA), or an alternative pattern (with the deformations occurring
predomitly in the central part of the nucleosomal DNA). The results presented
here may be useful for genome-wide classification of nucleosomes, linking
together structural and thermodynamic characteristics of nucleosomes with the
underlying DNA sequence patterns guiding their positions. MOTIVATION: The intrinsic DNA sequence is an important determit of nucleosome
positioning. Some DNA sequence patterns can facilitate nucleosome formation,
while others can inhibit nucleosome formation. Nucleosome positioning influences
the overall rate of sequence evolution. However, its impacts on specific
patterns of sequence evolution are still poorly understood.
RESULTS: Here, we examined whether nucleosomal DNA and nucleosome-depleted DNA
show distinct polymorphism patterns to maintain adequate nucleosome architecture
on a genome scale in yeast. We found that sequence polymorphisms in nucleosomal
DNA tend to facilitate nucleosome formation, whereas polymorphisms in
nucleosome-depleted DNA tend to inhibit nucleosome formation, which is
especially evident at nucleosome-disfavored sequences in nucleosome-free regions
at both ends of genes. Sequence polymorphisms facilitating nucleosome
positioning correspond to stable nucleosome positioning. These results reveal
that sequence polymorphisms are under selective constraints to maintain
nucleosome positioning.
CONTACT: [email protected]; [email protected] A major question in chromatin biology is to what extent the sequence of DNA
directly determines the genetic and chromatin organization of a eukaryotic
genome? We consider two aspects to this question: the DNA sequence-specified
positioning of nucleosomes and the determination of NDRs (nucleosome-depleted
regions) or barriers. We argue that, in budding yeast, while DNA
sequence-specified nucleosome positioning may contribute to positions flanking
the regions lacking nucleosomes, DNA thermodynamic stability is a major
component determit of the genetic organization of this organism. The fundamental repeating unit of eukaryotic chromatin is the nucleosome.
Besides being involved in packaging DNA, nucleosome organization plays an
important role in transcriptional regulation and cellular identity. Currently,
there is much debate about the major determits of the nucleosome architecture
of a genome and its significance with little being known about its role in stem
cells. To address these questions, we performed ultra-deep sequencing of
nucleosomal DNA in two human embryonic stem cell lines and integrated our data
with numerous epigenomic maps. Our analyses have revealed that the genome is a
determit of nucleosome organization with transcriptionally inactive regions
characterized by a "ground state" of nucleosome profiles driven by underlying
DNA sequences. DNA sequence preferences are associated with heterogeneous
chromatin organization around transcription start sites. Transcription, histone
modifications, and DNA methylation alter this "ground state" by having distinct
effects on both nucleosome positioning and occupancy. As the transcriptional
rate increases, nucleosomes become better positioned. Exons transcribed and
included in the final spliced mRNA have distinct nucleosome profiles in
comparison to exons not included at exon-exon junctions. Genes marked by the
active modification H3K4m3 are characterized by lower nucleosome occupancy
before the transcription start site compared to genes marked by the inactive
modification H3K27m3, while bivalent domains, genes associated with both marks,
lie exactly in the middle. Combinatorial patterns of epigenetic marks (chromatin
states) are associated with unique nucleosome profiles. Nucleosome organization
varies around transcription factor binding in enhancers versus promoters. DNA
methylation is associated with increasing nucleosome occupancy and different
types of methylations have distinct location preferences within the nucleosome
core particle. Finally, computational analysis of nucleosome organization alone
is sufficient to elucidate much of the circuitry of pluripotency. Our results,
suggest that nucleosome organization is associated with numerous genomic and
epigenomic processes and can be used to elucidate cellular identity. |
Which is the primary enzyme metabolizing esomeprazole? | Esomeprazole is primarily metabolized by CYP2C19. | |
Which factors contribute to the risk of very-early-onset inflammatory bowel disease? | Somalatic mosaicism and common genetic variation contribute to the risk of very-early-onset inflammatory bowel disease, particularly atrial fibrillation and dysregulation of transcphenne muscular dystrophy, as well as other genetic variation, in the early phase of disease. | Author information:
(1)MOE Key Laboratory of Gene Function and Regulation, Department of
Gastroenterology and Guangzhou Institute of Pediatrics, Guangzhou Women and
Children's Medical Center, School of Life Sciences, Sun Yat-sen University,
Guangzhou, China.
(2)MOE Key Laboratory of Gene Function and Regulation, Department of
Gastroenterology and Guangzhou Institute of Pediatrics, Guangzhou Women and
Children's Medical Center, School of Life Sciences, Sun Yat-sen University,
Guangzhou, China; Guangdong Provincial Key Laboratory of Gastroenterology,
Department of Gastroenterology, Nanfang Hospital, Southern Medical University,
Guangzhou, China.
(3)Biomedical Pioneering Innovation Center (BIOPIC), School of Life Sciences,
Peking University, Beijing, China.
(4)the Department of Pediatrics & Adolescent Medicine, The University of Hong
Kong, Hong Kong, China.
(5)Walter and Eliza Hall Institute of Medical Research and Departments of
Medical Biology and Microbiology & Immunology, University of Melbourne,
Parkville, Melbourne, Australia.
(6)the Department of Pediatrics & Adolescent Medicine, The University of Hong
Kong, Hong Kong, China. Electronic address: [email protected].
(7)MOE Key Laboratory of Gene Function and Regulation, Department of
Gastroenterology and Guangzhou Institute of Pediatrics, Guangzhou Women and
Children's Medical Center, School of Life Sciences, Sun Yat-sen University,
Guangzhou, China. Electronic address: [email protected].
(8)MOE Key Laboratory of Gene Function and Regulation, Department of
Gastroenterology and Guangzhou Institute of Pediatrics, Guangzhou Women and
Children's Medical Center, School of Life Sciences, Sun Yat-sen University,
Guangzhou, China. Electronic address: [email protected].
(9)MOE Key Laboratory of Gene Function and Regulation, Department of
Gastroenterology and Guangzhou Institute of Pediatrics, Guangzhou Women and
Children's Medical Center, School of Life Sciences, Sun Yat-sen University,
Guangzhou, China. Electronic address: [email protected]. |
What disease is treated with BIVV001? | BIVV001 fusion protein has been developed as Factor VIII replacement therapy for hemophilia A | BACKGROUND: Factor VIII replacement products have improved the care of patients
with hemophilia A, but the short half-life of these products affects the
patients' quality of life. The half-life of recombit factor VIII ranges from
15 to 19 hours because of the von Willebrand factor chaperone effect. BIVV001
(rFVIIIFc-VWF-XTEN) is a novel fusion protein designed to overcome this
half-life ceiling and maintain high sustained factor VIII activity levels. Data
are lacking on the safety and pharmacokinetics of single-dose BIVV001.
METHODS: In this phase 1-2a open-label trial, we consecutively assigned 16
previously treated men (18 to 65 years of age) with severe hemophilia A (factor
VIII activity, <1%) to receive a single intravenous injection of recombit
factor VIII at a dose of 25 IU per kilogram of body weight (lower-dose group) or
65 IU per kilogram (higher-dose group). This injection was followed by a washout
period of at least 3 days. The patients then received a single intravenous
injection of BIVV001 at the same corresponding dose of either 25 IU or 65 IU per
kilogram. Adverse events and pharmacokinetic measurements were assessed.
RESULTS: No inhibitors to factor VIII were detected and no hypersensitivity or
anaphylaxis events were reported up to 28 days after the injection of
single-dose BIVV001. The geometric mean half-life of BIVV001 was three to four
times as long as that of recombit factor VIII (37.6 hours vs. 9.1 hours in
the lower-dose group and 42.5 vs. 13.2 hours in the higher-dose group); the area
under the curve (AUC) for product exposure was six to seven times as great in
the two dose groups (4470 hours vs. 638 hours × IU per deciliter in the
lower-dose group and 12,800 hours vs. 1960 hours × IU per deciliter in the
higher-dose group). After the injection of BIVV001 in the higher-dose group, the
mean factor VIII level was in the normal range (≥51%) for 4 days and 17% at day
7, which suggested the possibility of a weekly interval between treatments.
CONCLUSIONS: In a small, early-phase study involving men with severe hemophilia
A, a single intravenous injection of BIVV001 resulted in high sustained factor
VIII activity levels, with a half-life that was up to four times the half-life
associated with recombit factor VIII, an increase that could signal a new
class of factor VIII replacement therapy with a weekly treatment interval. No
safety concerns were reported during the 28-day period after administration.
(Funded by Sanofi and Sobi; ClinicalTrials.gov number, NCT03205163.). |
What is the mode of action of Thiazovivin? | Thiazovivin is a selective small molecule that directly targets Rho-associated kinase (ROCK) and increases expression of pluripotency factors. | Today, there is a need for a platform to efficiently generate and maintain a
feeder free culture of pluripotent stem cells by small molecules or
pharmacological agents. Induced pluripotent stem cell (iPSC) is considered a
promising resource for restorative cell therapy in clinical areas. While fully
reprogrammed iPSCs are similar to embryonic stem cells, iPSCs could be derived
from the patient's own cells (autologous), which avoids the immune rejection
activities. Recent advances have demonstrated that iPSCs could be generated from
human fibroblasts using only four transcription factors: OCT4, SOX2, CMYC, and
KLF4. However, the limitations of reprogramming technologies include low
efficiency, slow kinetics, transgene integration and residual expression.
Surprisingly, adult stem cells from human endometrium (endometrial stem cells;
EnSCs) express OCT4 and KLF4 pluripotency factors. On the other hand, small
molecule inhibitors of specific signaling pathways such as thiazovivin have been
used in various aspects of iPSC generation and maintece. Thiazovivin is a
selective small molecule that directly targets Rho-associated kinase (ROCK) and
increases expression of pluripotency factors. The process using thiazovivin
could be easier, faster and more cost effective than transgene integration into
somatic cells. So reprogramming of OCT4 and KLF4 expressing EnSCs by a ROCK
inhibitor, thiazovivin, could result in producing more efficient iPSCs compared
with fibroblasts or conventional somatic cells without integration any transgene
and retroviral vector. Corneal diseases exhibit a high prevalence and are prone to cause blindness;
furthermore, maintaining the morphology and ionic transporter expression in
corneal endothelial cells (CECs) is crucial for treatment of these diseases.
This study aimed to investigate the effects of the novel Rho associated
coiled-coil containing protein kinase (ROCK) inhibitor,
thiazovivin (2,4‑disubstituted thiazole, TZV), on human corneal
endothelial‑to‑mesenchymal transition/epithelial‑to‑mesenchymal
transition (EndMT/EMT), cell morphology, junction proteins and ionic transporter
expression in human CECs (HCECs) in vitro and then to clarify the mechanisms of
action of TZV. In the present study, primary HCECs were cultured in vitro and
passaged. The expression levels of adhesion proteins (E‑cadherin and
N‑cadherin), the EndMT/EMT marker, α smooth muscle actin (α‑SMA), the tight
junction protein, Zonula occludens-1 (ZO‑1), and the ionic transporter,
Na+/K+‑ATPase, were detected by immunofluorescence. The proliferative ability of
the HCECs was determined by CCK-8 assay. The mRNA expression of the
EndMT/EMT‑inducing gene, Snail, was examined by RT‑PCR. The protein expression
levels of ROCK1/2 were evaluated by western blot analysis. The HCECs were
cultured with TZV at various concentrations (2, 4, or 6 µM) for different
periods of time (24 or 48 h). We found that the the cell states of the HCECs
co‑cultured with 4 µM TZV for 48 h reached the optimum, and corneal EndMT/EMT
was inhibited, as evidenced by the significantly upregulated expression of ZO‑1
and E‑cadherin, and the markedly downregulated expression of N‑cadherin and
α‑SMA. Furthermore, the cells exhibited a normal, tightly connected hexagonal or
pentagonal morphology. Additionally, the protein expression of ROCK1/2 and the
mRNA expression of Snail were significantly decreased. However, there was no
significant difference between the TZV‑treated and the control groups as regards
HCEC proliferative ability. These findings suggested that the ROCK inhibitor,
TZV (4 µM), was effective in improving the morphology, cell junctions and ionic
transporter expression of HCECs by inhibiting EndMT/EMT, but had no effect on
HCEC proliferation. |
Explain the association between Barr bodies (nuclear inclusions) and the X chromosome? | Barr body is an inactivated X chromosome in the normal female somatic cell. | Addition of exogen DB-c AMP in medium of human fibroblasts culture, with 46 XX
karyotypes, enables us to observe a high frequency of Barr bodies, about 80 or
85%. This observation suggests that the condensation of the X chromosome in the
form of Barr bodies depends on the level of endogen cyclic AMP. The chromosome in situ hybridization with human X chromosome alpha satellite DNA
probe (pBamX7) on human lymphocyte metaphases and interphase nuclei was
performed for interphase cytogenetic studies. The individuals with numerical or
structural abnormalities of X chromosome were studied. The results showed that
the probe hybridized specifically to the centromeric region (p11----q11) of X
chromosome. The number of silver grain clusters in interphase nuclei was
correlated with that of X chromosome. Most of the clusters located near the
nuclear membrane where inactive X chromatins (Barr-bodies) were usually found.
The method of ascertaining the number of X chromosomes by in situ hybridization
was much more reliable than that by counting the number of Barr-bodies. The
modified R-banding technique was introduced and the significance of this work
was also discussed. Transcriptional inactivation of one X chromosome in mammalian female somatic
cells leads to condensation of the inactive X chromosome into the
heterochromatic sex chromatin, or Barr body. Little is known about the molecular
composition and structure of the Barr body or the mechanisms leading to its
formation in female nuclei. Because human sera from patients with autoimmune
diseases often contain antibodies against a variety of cellular components, we
reasoned that some autoimmune sera may contain antibodies against proteins
associated with the Barr body. Therefore, we screened autoimmune sera by
immunofluorescence of human fibroblasts and identified one serum that
immunostained a distinct nuclear structure with a size and nuclear localization
consistent with the Barr body. The number of these structures was consistent
with the number of Barr bodies expected in diploid female fibroblasts containing
two to five X chromosomes. Immunostaining with the serum followed by
fluorescence in situ hybridization with a probe against XIST RNA demonstrated
that the major fluorescent signal from the autoantibody colocalized with XIST
RNA. Further analysis of the serum showed that it stains human metaphase
chromosomes and a nuclear structure consistent with the inactive X in female
mouse fibroblasts. However, it does not exhibit localization to a Barr body-like
structure in female mouse embryonic stem cells or in cells from female mouse
E7.5 embryos. The lack of staining of the inactive X in cells from female E7.5
embryos suggests the antigen(s) may be involved in X inactivation at a stage
subsequent to initiation of X inactivation. This demonstration of an
autoantibody recognizing an antigen(s) associated with the Barr body presents a
strategy for identifying molecular components of the Barr body and examining the
molecular basis of X inactivation. The Barr body has long been recognized as the cytological manifestation of the
inactive X chromosome (Xi) in interphase nuclei. Despite being known for over 50
years, relatively few components of the Barr body have been identified. In this
study, we have screened over 30 histone variants, modified histones and
non-histone proteins for their association with or exclusion from the Barr body.
We demonstrate that, similar to the histone variant macroH2A, heterochromatin
protein-1 (HP1), histone H1 and the high mobility group protein HMG-I/Y are
elevated at the territory of the Xi in interphase in human cell lines, but only
when the Xi chromatin is heteropycnotic, implicating each as a component of the
Barr body. Surprisingly, however, virtually all other candidate proteins
involved in establishing heterochromatin and gene silencing are notably absent
from the Barr body despite being localized generally elsewhere throughout the
nucleus, indicating that the Barr body represents a discrete subnuclear
compartment that is not freely accessible to most chromatin proteins. A similar
dichotomous pattern of association or exclusion describes the spatial
relationship of a number of specific histone methylation patterns in relation to
the Barr body. Notably, though, several methylated forms of histone H3 that are
deficient in Xi chromatin generally are present at a region near the
macrosatellite repeat DXZ4, as are the chromatin proteins CTCF and SAP30,
indicating a distinctive chromatin state in this region of the Xi. Taken
together, our data imply that the Xi adopts a distinct chromatin configuration
in interphase nuclei and are consistent with a mechanism by which HP1, through
histone H3 lysine-9 methylation, recognizes and assists in maintaining
heterochromatin and gene silencing at the human Xi. Barr body is an inactivated X chromosome in the normal female somatic cell.
Inactivation of these chromosomes is known as Lyonization. Lyonization has both
genetic and clinical significance. Barr body can be easily identified with
ordinary stains. It also helps in identifying the sex of an individual when used
judiciously. A review is made on the lyonization of Barr body and its utility in
sex determination. The radial positions of the centromeric regions of chromosomes 1 and X were
determined in normal male fibroblasts (XY) and in fibroblasts from a patient
with a rare case of XXXXY polysomy. The centromeric regions and presumably the
whole territories of active X chromosomes were demonstrated to occupy similar,
although not identical, positions in XY and XXXXY cells. The centromeres of
inactive X chromosomes (Barr bodies) were located closer to the nuclear
periphery as compared with the centromeres of active X chromosomes. In addition,
it was established that the nuclear radial position of gene-rich chromosome 1
was changed in XXXXY cells as compared to normal XY cells. The data are
discussed in the context of the hypothesis postulating that changes in nuclear
positioning of chromosomal territories induced by the presence of extra copies
of individual chromosomes may contribute to the development of diseases related
to different polysomies. Interest has recently reawakened in whether loss of the heterochromatic X
chromosome (Barr body) is prevalent in certain breast and ovarian cancers, and
new insights into the mechanisms involved have emerged. Mitotic segregation
errors commonly explain the loss of the inactive X chromosome (Xi), but
compromise of Xi heterochromatin in some cancers may signal broader deficits of
nuclear heterochromatin. The debated link between BRCA1 and Xi might reflect a
general relationship between BRCA1 and heterochromatin, which could connect
BRCA1 to both epigenetic and genetic instability. We suggest that
heterochromatic instability is a common but largely unexplored mechanism,
leading to widespread genomic misregulation and the evolution of some cancers. The Barr body is the inactive X chromosome in a female somatic cell. It is
readily identified as plano-convex structure of 2-3 micron in diameter on the
periphery of the nuclear membrane. The aim of this study is to evaluate the
significance of Barr body count in maligt ovarian tumors on fine needle
aspiration cytology (FNAC) smears. In this retrospective study, Barr body was
counted in FNAC smears of 20 successive maligt ovarian lesions and expressed
as percentage. Mean (±SD) Barr body score was 2.4 ± 2.58. Minimum Barr body
count was 1 and maximum was 9. The gross reduction of Barr body in ovarian
neoplasms is an interesting cytomorphologic finding. Human inactive X chromosome (Xi) forms a compact structure called the Barr body,
which is enriched in repressive histone modifications such as trimethylation of
histone H3 Lys9 (H3K9me3) and Lys27 (H3K27me3). These two histone marks are
distributed in distinct domains, and X-inactive specific transcript (XIST)
preferentially colocalizes with H3K27me3 domains. Here we show that Xi
compaction requires HBiX1, a heterochromatin protein 1 (HP1)-binding protein,
and structural maintece of chromosomes hinge domain-containing protein 1
(SMCHD1), both of which are enriched throughout the Xi chromosome. HBiX1
localization to H3K9me3 and XIST-associated H3K27me3 (XIST-H3K27me3) domains was
mediated through interactions with HP1 and SMCHD1, respectively. Furthermore,
HBiX1 was required for SMCHD1 localization to H3K9me3 domains. Depletion of
HBiX1 or SMCHD1, but not Polycomb repressive complex 2 (PRC2), resulted in Xi
decompaction, similarly to XIST depletion. Thus, the molecular network involving
HBiX1 and SMCHD1 links the H3K9me3 and XIST-H3K27me3 domains to organize the
compact Xi structure. BACKGROUND: Cytogenetic studies from past decades have shown that interphase
cells of female cats contain a densely stained chromatin mass in their nuclei
called as Barr bodies (BBs) named after the scientist Murray Barr. BBs are
unique chromatin structures formed due to the condensation of the X-chromosome.
Many psychopathic disorders originate from defective genes including the
multiple X syndromes. Males with extra X-chromosome generally present with
severe personality disorder. The present study was conducted to determine the
presence of extra X-chromosome in male jail inmates through the detection of BB
in peripheral blood and buccal smear.
MATERIALS AND METHODS: Study included 100 male subjects (fifty jail inmates and
fifty controls), after obtaining the consent, peripheral blood smears (PBS) and
buccal smears (BS) were prepared and stained using Leishman's and cresyl violet
stain respectively. One hundred neutrophils in PBS and epithelial cells in BS
were screened for detection of the BB; accumulated data were tabulated and
statistically analyzed using t-test and Chi-square test.
RESULTS: 60% of cases in PBS and 36% in BS showed positivity for the presence of
BB in jail inmates as compared to 14% of cases in PBS and none in BS were
positive for BB in controls.
CONCLUSION: Presence of BB in male suggests increased likelihood of criminal
tendencies. Further studies are to be carried out to compare the results with
karyotyping. Granulocytic early progenitors and terminally differentiated - mature
granulocytes with segmented nuclei were studied using computer-assisted diameter
and heterochromatin optical image densitometry to provide more information on
the nuclear size and heterochromatin condensation state. Bone marrow smears of
patients suffering from chronic myeloid leukaemia untreated as well as treated
with "specific" anti-leukaemic therapy with imatinib mesylate are a convenient
model for such study because they possess a satisfactory number of cells for
diameter and optical density measurements. In addition, the identification of
developmental stages of granulocytes is very easy and the morphology is not
different from that in not-leukaemic persons. As it was expected, the mean
diameter of nuclear segments in fully differentiated and mature granulocytes was
much smaller than that in non-segmented nuclei of early granulocytic precursors.
Therefore, no wonder that the heterochromatin condensation state in nuclear
segments of mature granulocytes was much larger than in non-segmented nuclei of
granulocytic progenitors. On the other hand, the sum of mean diameters of all
nuclear segments per cell was close to the mean nuclear diameter of early
granulocytic progenitors. The heterochromatin condensation state in granulocytic
progenitors or fully differentiated mature granulocytes exhibited marked
stability and did not change after the anti-leukaemic therapy. In addition, Barr
bodies of characteristic drumstick appearance bearing inactive X chromosome in
interphase nuclei of mature granulocytes in fertile female patients exhibited a
heterochromatin condensation state similar to nuclear segments. This
heterochromatin condensation state was also stable and constant, and was not
apparently influenced by the anti-leukaemic therapy. |
Is the zelda transcription factor a chromatin remodeller? | During developmental transition, the zygotic genome is largely transcriptionally quiescent and undergoes significant chromatin remodeling. In Drosophila, the DNA-binding protein Zelda (also known as Vielfaltig) is required for this transition and for transcriptional activation of the zygotic genome. Zelda is differentially required for chromatin accessibility, transcription factor binding, and gene expression in the early Drosophila embryo. Zelda overcomes the high intrinsic nucleosome barrier at enhancers during Drosophila zygotic genome activation. Early enhancers are characterized by an intrinsically high nucleosome barrier. Zelda tackles this nucleosome barrier through local depletion of nucleosomes with the effect being dependent on the number and position of zelda(zld) motifs. | The trithorax group (trxG) of activators and Polycomb group (PcG) of repressors
are believed to control the expression of several key developmental regulators
by changing the structure of chromatin. Here, we have sought to dissect the
requirements for transcriptional activation by the Drosophila trxG protein
Zeste, a DNA-binding activator of homeotic genes. Reconstituted transcription
reactions established that the Brahma (BRM) chromatin-remodeling complex is
essential for Zeste-directed activation on nucleosomal templates. Because it is
not required for Zeste to bind to chromatin, the BRM complex appears to act
after promoter binding by the activator. Purification of the Drosophila BRM
complex revealed a number of novel subunits. We found that Zeste tethers the BRM
complex via direct binding to specific subunits, including trxG proteins Moira
(MOR) and OSA. The leucine zipper of Zeste mediates binding to MOR.
Interestingly, although the Imitation Switch (ISWI) remodelers are potent
nucleosome spacing factors, they are dispensable for transcriptional activation
by Zeste. Thus, there is a distinction between general chromatin restructuring
and transcriptional coactivation by remodelers. These results establish that
different chromatin remodeling factors display distinct functional properties
and provide novel insights into the mechanism of their targeting. Zygotic genome activation (ZGA) is a major genome programming event whereby the
cells of the embryo begin to adopt specified fates. Experiments in Drosophila
and zebrafish have revealed that ZGA depends on transcription factors that
provide large-scale control of gene expression by direct and specific binding to
gene regulatory sequences. Zelda (Zld) plays such a role in the Drosophila
embryo, where it has been shown to control the action of patterning signals;
however, the mechanisms underlying this effect remain largely unclear. A recent
model proposed that Zld binding sites act as quantitative regulators of the
spatiotemporal expression of genes activated by Dorsal (Dl), the morphogen that
patterns the dorsoventral axis. Here we tested this model experimentally, using
enhancers of brinker (brk) and short gastrulation (sog), both of which are
directly activated by Dl, but at different concentration thresholds. In
agreement with the model, we show that there is a clear positive correlation
between the number of Zld binding sites and the spatial domain of enhancer
activity. Likewise, the timing of expression could be advanced or delayed. We
present evidence that Zld facilitates binding of Dl to regulatory DNA, and that
this is associated with increased chromatin accessibility. Importantly, the
change in chromatin accessibility is strongly correlated with the change in Zld
binding, but not Dl. We propose that the ability of genome activators to
facilitate readout of transcriptional input is key to widespread transcriptional
induction during ZGA. In this review, we discuss a novel on-site remodeling function that is mediated
by the H2A-ubiquitin binding protein ZRF1. ZRF1 facilitates the remodeling of
multiprotein complexes at chromatin and lies at the heart of signaling processes
that occur at DNA damage sites and during transcriptional activation. In
nucleotide excision repair ZRF1 remodels E3 ubiquitin ligase complexes at the
damage site. During embryonic stem cell differentiation, it contributes to
retinoic acid-mediated gene activation by altering the subunit composition of
the Mediator complex. We postulate that ZRF1 operates in conjunction with
cellular remodeling machines and suggest that on-site remodeling might be a
hallmark of many chromatin-associated signaling pathways. We discuss yet
unexplored functions of ZRF1-mediated remodeling in replication and double
strand break repair. In conclusion, we postulate that on-site remodeling of
multiprotein complexes is essential for the timing of chromatin signaling
processes. In the endopterygote Drosophila melanogaster, Zelda is an activator of the
zygotic genome during the maternal-to-zygotic transition (MZT). Zelda binds
cis-regulatory elements (TAGteam heptamers), making chromatin accessible for
gene transcription. Zelda has been studied in other endopterygotes:
Apis mellifera and Tribolium castaneum, and the paraneopteran Rhodnius prolixus.
We studied Zelda in the cockroach Blattella germanica, a hemimetabolan, short
germ-band, and polyneopteran species. B. germanica Zelda has the complete set of
functional domains, which is typical of species displaying ancestral features
concerning embryogenesis. Interestingly, we found D. melanogaster TAGteam
heptamers in the B. germanica genome. The canonical one, CAGGTAG, is present at
a similar proportion in the genome of these two species and in the genome of
other insects, suggesting that the genome admits as many CAGGTAG motifs as its
length allows. Zelda-depleted embryos of B. germanica show defects involving
blastoderm formation and abdomen development, and genes contributing to these
processes are down-regulated. We conclude that in B. germanica, Zelda strictly
activates the zygotic genome, within the MZT, a role conserved in more derived
endopterygote insects. In B. germanica, zelda is expressed during MZT, whereas
in D. melanogaster and T. castaneum it is expressed beyond this transition. In
these species and A. mellifera, Zelda has functions even in postembryonic
development. The expansion of zelda expression beyond the MZT in endopterygotes
might be related with the evolutionary innovation of holometabolan
metamorphosis. DATABASES: The RNA-seq datasets of B. germanica, D. melanogaster,
and T. castaneum are accessible at the GEO databases GSE99785, GSE18068,
GSE63770, and GSE84253. In addition, the RNA-seq library from T. castaneum adult
females is available at SRA: SRX021963. The B. germanica reference genome is
available as BioProject PRJNA203136. |
What is the effect of the alleles CYP2C19*2 and CYP2C19*3 on CYP2C19 function? | The CYP2C19*2 and CYP2C19*3 alleles of CYP2C19 are associated with loss-of-function (LOF). | BACKGROUND: The CYP2C19*2 or *3 loss-of-function (LOF) allele is associated with
high platelet reactivity (HPR) on clopidogrel treatment. East Asians may benefit
from a lower dose of prasugrel due to their more potent platelet inhibitory
response. The impact of LOF alleles on the pharmacodynamic response to half-dose
prasugrel in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS)
undergoing percutaneous coronary intervention (PCI) is unknown.
METHODS: Seventy patients with the LOF alleles were assigned to half-dose
prasugrel (n = 35, 30-mg load followed by 5 mg daily) or clopidogrel (n = 35,
600-mg load followed by 75 mg daily). The primary endpoint was the rate of HPR,
defined as VerifyNow-P2Y12 reaction unit (PRU) >235, at 24 h post loading.
RESULTS: Prasugrel achieved a lower PRU compared to clopidogrel after loading
(119 [56-175] vs. 245 [189-299]), at 24 h (34 [8-58] vs. 196 [122-244]), and at
30 days (134 [98-189] vs. 203 [144-248]). Prasugrel had a lower rate of HPR
after loading (5.7% vs. 57.1%, p <0.001), at 24 h (2.9% vs. 28.6%, p=0.006), and
at 30 days (11.4% vs. 34.3%, p=0.004). Prasugrel had a similar rate of optimal
platelet reactivity at 30 days (71.4% vs. 60.0%, p=0.450). There was no
significant difference in the occurrence of periprocedural myonecrosis within
48 h after PCI with clopidogrel and prasugrel (22.9% vs. 17.1%, p>0.960).
CONCLUSIONS: Half-dose prasugrel provided potent platelet inhibition in NSTE-ACS
patients that were carriers of the CYP2C19*2 or *3 allele, with a lower rate of
HPR. Periprocedural myonecrosis was not significantly different in the 2 groups. |
Describe Full Spectrum of Intolerance to Loss-of-function (FUSIL) | Full Spectrum of Intolerance to Loss-of-function (FUSIL) is a cross-species gene classification across the full spectrum of mutations in genes of unknown function. FUSIL has been proposed as a method to identify potentially pathogenic variants in genes not previously associated with rare diseases. | Author information:
(1)Clinical Pharmacology, William Harvey Research Institute, School of Medicine
and Dentistry, Queen Mary University of London, London, EC1M 6BQ, UK.
(2)European Molecular Biology Laboratory, European Bioinformatics Institute
(EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, UK.
(3)The Jackson Laboratory, Bar Harbor, ME, 4609, USA.
(4)Departments of Molecular Physiology and Biophysics, Baylor College of
Medicine, Houston, TX, 77030, USA.
(5)Departments of Molecular and Human Genetics, Baylor College of Medicine,
Houston, TX, 77030, USA.
(6)Department of Genetics, Perelman School of Medicine, University of
Pennsylvania, Philadelphia, PA, 19104, USA.
(7)The Centre for Phenogenomics, The Hospital for Sick Children, Toronto, ON,
M5T 3H7, Canada.
(8)The Centre for Phenogenomics, Lunenfeld-Tanenbaum Research Institute, Mount
Sinai Hospital, Toronto, ON, M5T 3H7, Canada.
(9)Medical Research Council Harwell Institute (Mammalian Genetics Unit and Mary
Lyon Centre), Harwell, Oxfordshire, OX11 0RD, UK.
(10)German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum
München, German Research Center for Environmental Health, 85764, Neuherberg,
Germany.
(11)Université de Strasbourg, CNRS, INSERM, Institut Clinique de la Souris,
PHENOMIN-ICS, 67404, Illkirch, France.
(12)Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech
Academy of Sciences, Vestec, 252 50, Prague, Czech Republic.
(13)Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK.
(14)Institute of Developmental Genetics, Helmholtz Zentrum München, German
Research Center for Environmental Health GmbH, 85764, Neuherberg, Germany.
(15)Department of Developmental Genetics, Center of Life and Food Sciences
Weihenstephan, Technische Universität München, 85764, Neuherberg, Germany.
(16)Deutsches Institut für Neurodegenerative Erkrankungen (DZNE) Site Munich,
Munich Cluster for Systems Neurology (SyNergy), Adolf-Butedt-Institut,
Ludwig-Maximilians-Universität München, 80336, Munich, Germany.
(17)Monterotondo Mouse Clinic, Italian National Research Council (CNR),
Institute of Cell Biology and Neurobiology, 00015, Monterotondo Scalo, Italy.
(18)Translational Medicine, The Hospital for Sick Children, Toronto, ON, M5T
3H7, Canada.
(19)Université de Strasbourg, CNRS, INSERM, Institut de Génétique, Biologie
Moléculaire et Cellulaire, Institut Clinique de la Souris, IGBMC, PHENOMIN-ICS,
67404, Illkirch, France.
(20)Department of Experimental Genetics, Center of Life and Food Sciences
Weihenstephan, Technische Universität München, 85354, Freising-Weihenstephan,
Germany.
(21)German Center for Diabetes Research (DZD), 85764, Neuherberg, Germany.
(22)Mouse Biology Program, University of California, Davis, CA, 95618, USA.
(23)Clinical Pharmacology, William Harvey Research Institute, School of Medicine
and Dentistry, Queen Mary University of London, London, EC1M 6BQ, UK.
[email protected].
(#)Contributed equally |
Is capmatinib effective for glioblastoma? | No. Combination of capmatinib buparlisib resulted in no clear activity in patients with recurrent PTEN-deficient glioblastoma. | Conflict of interest statement: In relation to this presentation, we declare the
following, real or perceived conflicts of interest: M. van den Bent has received
grants from Abbvie, and honoraria from Cellgene, BMS, Boehringer, AGIOS and
VaXIMM. A. Azaro has received consulting fees from Orion Pharmaceuticals and
Amcure GmbH. F. De Vos has received ficial support for conducting clinical
trials from Novartis, BMS, AbbVie and Bioclin. J.M. Sepulveda has received
consulting fees from Celgene, Pfizer and Abbvie; he has received research grants
from Pfizer and Catalysis. W.K.A. Yung holds stocks in DNATrix; he has received
honoraria from DNATrix and Boehringer Ingelheim; he holds patents, royalties
and/or intellectual property in, and has participated in a consulting or
advisory role for DNATrix; he has received travel and/or accommodation expenses
from Boehringer Ingelheim. P. Wen has received grants/research support from
Lilly USA, Agios, AstraZeneca, Beigene, Eli Lily, Immunocellular Therapeutics,
Kazai, Kadmon, Karyopharm, Merck, Novartis, Oncoceutics, Vascular Biogenics and
Vaccines; he has received speaker’s bureau fees from Merck; he has received
consultant/advisory board fees from Genentech/Roche, Taiho Oncology, Novartis,
Agios Pharmaceuticals Inc, Merck, Puma, Abbvie, AstraZeneca, Eli Lilly, GW
Pharmaceuticals, Immunomic Therapeutics, Kadmon, Vascular Biogenics, Ziopharm,
Monteris and Tocagen. A. Lassman reports grants and non-ficial support from
Novartis, during the conduct of the study; personal fees and non-ficial
support from Orbus, grants, personal fees and non-ficial support from
Karyopharm, personal fees and non-ficial support from NW Biotherapeutics,
grants and non-ficial support from Oncoceutics, personal fees and
non-ficial support from Agios, personal fees and non-ficial support from
Celgene, personal fees and non-ficial support from Novocure, non-ficial
support from Tocagen, non-ficial support from BMS, grants, personal fees and
non-ficial support from Kadmon, grants and non-ficial support from
Genentech/Roche, grants and non-ficial support from Amgen, grants and
non-ficial support from Millenium, non-ficial support from Celldex, grants
and non-ficial support from Pfizer, non-ficial support from Keryx/Aeterna
Zentaris, grants and non-ficial support from VBI Vaccines, grants and
non-ficial support from Beigene, personal fees from Bioclinica as an expert
blinded independent reviewer of clinical and imaging data for a BMS-sponsored
trial, personal fees from prIME Oncology, personal fees and non-ficial
support from Sapience, personal fees from WebMD, personal fees and non-ficial
support from Physicians' Education Resource, personal fees from Cortice, grants,
personal fees and non-ficial support from AbbVie, personal fees and
non-ficial support from Forma, personal fees and non-ficial support from
Bayer, grants and non-ficial support from Global Coalition for Adaptive
Research, personal fees and non-ficial support from American Society of
Clinical Oncology, grants and non-ficial support from QED, grants, personal
fees and non-ficial support from NCI, non-ficial support from New York
University, grants and non-ficial support from NRG Oncology/RTOG-Foundations,
grants from UCLA, grants from Northwestern University, grants from James S.
McDonnell Foundation, non-ficial support from Yale University, non-ficial
support from Radiological Society of North America, non-ficial support from
FDA, personal fees from Italian Foundation for Cancer Research, personal fees
and non-ficial support from Abbott Molecular, and personal fees from
Elsevier, outside the submitted work M. Joerger has received grants from BMS and
AstraZeneca. G. Tabatabai has served on Advisory Boards for AbbVie and BMS, has
received research/travel grants from Medac, Novocure and Roche Diagnostics, and
has received speaker`s fees from Meda and Novocure. J. Rodon reports
non-ficial support and reasonable reimbursement for travel from European
Journal of Cancer, Vall d'Hebron Institut of Oncology, Chinese University of
Hong Kong, SOLTI, Elsevier, GlaxoSmithKline; receiving consulting and travel
fees from Novartis, Eli Lilly, Orion Pharmaceuticals, Servier Pharmaceuticals,
Peptomyc, Merck Sharp & Dohme, Kelun Pharmaceutical/Klus Pharma, Spectrum
Pharmaceuticals Inc, Pfizer, Roche Pharmaceuticals, Ellipses Pharma (including
serving on the scientific advisory board from 2015-present), receiving research
funding from Bayer and Novartis, and serving as investigator in clinical trials
with Spectrum Pharmaceuticals, Tocagen, Symphogen, BioAtla, Pfizer, GenMab,
CytomX, Kelun-Biotech, Takeda-Millenium, GlaxoSmithKline, IPSEN and travel fees
from ESMO, US Department of Defense, Louissiana State University, Hunstman
Cancer Institute, Cancer Core Europe, Karolinska Cancer Institute and King
Abdullah International Medical Research Center (KAIMRC). R. Tiedt, T. Kirsilae
and S. Vicente are employees of Novartis Pharma AG. S. Zhao is an employee of
Novartis Institutes for Biomedical Research (China). A. Balbin is an employee of
Novartis Institutes for Biomedical Research (US). H. Zhang is an employee of
Novartis and holds shares with Novartis. W. Wick receives study support to the
institution from Apogenix, Pfizer and Roche. |
Are there antimicrobial proteins in royal jelly? | Yes,
Jelleines, isolated as novel antibacterial peptides from the Royal Jelly (RJ) of bees, exhibit broad-spectrum protection against microbial infections. | Typically, antimicrobial peptides (AMPs) are short positive charged peptides
serving a key role in innate immunity as well as antimicrobial activity.
Discovering novel therapeutic agents is considered as an undeniable demand due
to increasing microbial species with antibiotic resistance. In this direction,
the unique ability of AMPs to modulate immune responses highlighted them as
novel drug candidates in the field of microbiology. Patients affected by
leishmaniasis; a neglected tropical disease, confront serious problems for their
treatment including resistance to common drugs as well as toxicity and high cost
of therapy. So, there is a need for development of new drug candidates to
control the diseases. Jellein, a peptide derived from royal jelly of honeybee
has been shown to have promising effect against several bacterial and fungal
species. In current study, anti-leishmanial effect of Jellein and its lauric
acid conjugated form was investigated against two forms of Leishmania major (L.
major) parasite. Moreover, cytotoxic effect of these peptides was studied in
THP1 cell line and human Red Blood Cells (RBCs). Furthermore, the mechanism of
action of peptides on L. major promastigotes was assessed through different
methods. The results demonstrated that, conjugation of lauric acid to Jellein
not only had no effect on the elevation of antimicrobial activity but also
halted it completely. Moreover, Jellein caused a limitation in the number of L.
major promastigotes by pore formation as well as changing the membrane potential
rather than induction of apoptosis or activation of caspases. Royal jelly (RJ) is a yellowish-white and acidic secretion of hypopharyngeal and
mandibular glands of nurse bees used to feed young worker larvae during the
first three days and the entire life of queen bees. RJ is one of the most
appreciated and valued natural product which has been mainly used in traditional
medicines, health foods, and cosmetics for a long time in different parts of the
world. It is also the most studied bee product, aimed at unravelling its
bioactivities, such as antimicrobial, antioxidant, anti-aging, immunomodulatory,
and general tonic action against laboratory animals, microbial organisms, farm
animals, and clinical trials. It is commonly used to supplement various
diseases, including cancer, diabetes, cardiovascular, and Alzheimer's disease.
Here, we highlight the recent research advances on the main bioactive compounds
of RJ, such as proteins, peptides, fatty acids, and phenolics, for a
comprehensive understanding of the biochemistry, biological, and pharmaceutical
responses to human health promotion and life benefits. This is potentially
important to gain novel insight into the biological and pharmaceutical
properties of RJ. |
What are the years of the initiation and completion of the Human Genome project? | The Human Genome Project was initiated in 1990 and completed in 2003. | Information obtained from the Human Genome Project, initiated in 1990 and
targeted for completion in 2005, will influence both health care and nursing
practice. It will substantially revise our understanding of disease
susceptibility and causation. Additional genetic tests will be developed and
gene therapies explored. The project has implications for both nursing research
and nursing practice. This article reviews the establishment of the Human Genome
Project, reports on current progress of the project, and identifies some
implications of the project for health care generally and nursing specifically. The Human Genome Project (HGP) was initiated in 1990 and completed in 2003. It
aimed to sequence the whole human genome. Although it represented an advance in
understanding the human genome and its complexity, many questions remained
uswered. Other projects were launched in order to unravel the mysteries of
our genome, including the ENCyclopedia of DNA Elements (ENCODE). This review
aims to analyze the evolution of scientific knowledge related to both the HGP
and ENCODE projects. Data were retrieved from scientific articles published in
1990-2014, a period comprising the development and the 10 years following the
HGP completion. The fact that only 20,000 genes are protein and RNA-coding is
one of the most striking HGP results. A new concept about the organization of
genome arose. The ENCODE project was initiated in 2003 and targeted to map the
functional elements of the human genome. This project revealed that the human
genome is pervasively transcribed. Therefore, it was determined that a large
part of the non-protein coding regions are functional. Finally, a more
sophisticated view of chromatin structure emerged. The mechanistic functioning
of the genome has been redrafted, revealing a much more complex picture.
Besides, a gene-centric conception of the organism has to be reviewed. A number
of criticisms have emerged against the ENCODE project approaches, raising the
question of whether non-conserved but biochemically active regions are truly
functional. Thus, HGP and ENCODE projects accomplished a great map of the human
genome, but the data generated still requires further in depth analysis. © 2016
by The International Union of Biochemistry and Molecular Biology, 44:215-223,
2016. Since the completion of the Human Genome Project in 2003 and the announcement of
the Precision Medicine Initiative by U.S. President Barack Obama in January
2015, human beings have initially completed the " three steps" of " genomics to
biology, genomics to health as well as genomics to society". As a new
inter-discipline, the emergence and development of precision medicine have
relied on the support and promotion from biological science, basic medicine,
clinical medicine, epidemiology, statistics, sociology and information science,
etc. Meanwhile, molecular epidemiology is considered to be the core power to
promote precision medical as a cross discipline of epidemiology and molecular
biology. This article is based on the characteristics and research progress of
medicine and molecular epidemiology respectively, focusing on the contribution
and significance of molecular epidemiology to precision medicine, and exploring
the possible opportunities and challenges in the future. Lately, the term "genomics" has become ubiquitous in many scientific articles.
It is a rapidly growing aspect of the biomedical sciences that studies the
genome. The human genome contains a torrent of information that gives clues
about human origin, evolution, biological function, and diseases. In a bid to
demystify the workings of the genome, the Human Genome Project (HGP) was
initiated in 1990, with the chief goal of sequencing the approximately 3 billion
nucleotide base pairs of the human DNA. Since its completion in 2003, the HGP
has opened new avenues for the application of genomics in clinical practice.
This review attempts to overview some milestone discoveries that paved way for
the initiation of the HGP, remarkable revelations from the HGP, and how genomics
is influencing a paradigm shift in routine clinical practice. It further
highlights the challenges facing the implementation of genomic medicine,
particularly in Africa. Possible solutions are also discussed. |
Which methods infer 3D genome structure without proximity ligation? | SPRITE is a method that enables genome-wide detection of higher-order interactions within the nucleus.
Transposase-mediated analysis of chromatin looping (Trac-looping) for simultaneous detection of multiscale genome-wide chromatin interactions among regulatory elements and chromatin accessibility.
Genome architecture mapping (GAM) can be used for measuring chromatin contacts and other features of three-dimensional chromatin topology on the basis of sequencing DNA from a large collection of thin nuclear sections. | Since Jacob and Monod's characterization of the role of DNA elements in gene
control, it has been recognized that the linear organization of genome structure
is important for the regulation of gene transcription and hence the
manifestation of phenotypes. Similarly, it has long been hypothesized that the
spatial organization (in three dimensions evolving through time), as part of the
epigenome, makes a significant contribution to the genotype-phenotype
transition. Proximity ligation assays commonly known as chromosome conformation
capture (3C) and 3C based methodologies (e.g., GCC, HiC and ChIA-Pet) are
increasingly being incorporated into empirical studies to investigate the role
that three-dimensional genome structure plays in the regulation of phenotype.
The apparent simplicity of these methodologies-crosslink chromatin, digest,
dilute, ligate, detect interactions-belies the complexity of the data and the
considerations that should be taken into account to ensure the generation and
accurate interpretation of reliable data. Here we discuss the probabilistic
nature of these methodologies and how this contributes to their endogenous
limitations. BACKGROUND: Several recently developed experimental methods, each an extension
of the chromatin conformation capture (3C) assay, have enabled the genome-wide
profiling of chromatin contacts between pairs of genomic loci in 3D. Especially
in complex eukaryotes, data generated by these methods, coupled with other
genome-wide datasets, demonstrated that non-random chromatin folding correlates
strongly with cellular processes such as gene expression and DNA replication.
RESULTS: We describe a genome architecture assay, tethered multiple 3C (TM3C),
that maps genome-wide chromatin contacts via a simple protocol of restriction
enzyme digestion and religation of fragments upon agarose gel beads followed by
paired-end sequencing. In addition to identifying contacts between pairs of
loci, TM3C enables identification of contacts among more than two loci
simultaneously. We use TM3C to assay the genome architectures of two human cell
lines: KBM7, a near-haploid chronic leukemia cell line, and NHEK, a normal
diploid human epidermal keratinocyte cell line. We confirm that the contact
frequency maps produced by TM3C exhibit features characteristic of existing
genome architecture datasets, including the expected scaling of contact
probabilities with genomic distance, megabase scale chromosomal compartments and
sub-megabase scale topological domains. We also confirm that TM3C captures
several known cell type-specific contacts, ploidy shifts and translocations,
such as Philadelphia chromosome formation (Ph+) in KBM7. We confirm a subset of
the triple contacts involving the IGF2-H19 imprinting control region (ICR) using
PCR analysis for KBM7 cells. Our genome-wide analysis of pairwise and triple
contacts demonstrates their preference for linking open chromatin regions to
each other and for linking regions with higher numbers of DNase hypersensitive
sites (DHSs) to each other. For near-haploid KBM7 cells, we infer whole genome
3D models that exhibit clustering of small chromosomes with each other and large
chromosomes with each other, consistent with previous studies of the genome
architectures of other human cell lines.
CONCLUSION: TM3C is a simple protocol for ascertaining genome architecture and
can be used to identify simultaneous contacts among three or four loci.
Application of TM3C to a near-haploid human cell line revealed large-scale
features of chromosomal organization and multi-way chromatin contacts that
preferentially link regions of open chromatin. High-throughput assays of three-dimensional interactions of chromosomes have
shed considerable light on the structure of animal chromatin. Despite this
progress, the precise physical nature of observed structures and the forces that
govern their establishment remain poorly understood. Here we present high
resolution Hi-C data from early Drosophila embryos. We demonstrate that
boundaries between topological domains of various sizes map to DNA elements that
resemble classical insulator elements: short genomic regions sensitive to DNase
digestion that are strongly bound by known insulator proteins and are frequently
located between divergent promoters. Further, we show a striking correspondence
between these elements and the locations of mapped polytene interband regions.
We believe it is likely this relationship between insulators, topological
boundaries, and polytene interbands extends across the genome, and we therefore
propose a model in which decompaction of boundary-insulator-interband regions
drives the organization of interphase chromosomes by creating stable physical
separation between adjacent domains. The packaging of DNA inside a nucleus shows complex structure stabilized by a
host of DNA-bound factors. Both the distribution of these factors and the
contacts between different genomic locations of the DNA can now be measured on a
genome-wide scale. This has advanced the development of models aimed at
predicting the conformation of DNA given only the locations of bound factors-the
chromatin folding problem. Here we present a maximum-entropy model that is able
to predict a contact map representation of structure given a sequence of bound
factors. Non-local effects due to the sequence neighborhood around contacting
sites are found to be important for making accurate predictions. Lastly, we show
that the model can be used to infer a sequence of bound factors given only a
measurement of structure. This opens up the possibility for efficiently
predicting sequence regions that may play a role in generating cell-type
specific structural differences. Eukaryotic genomes are packaged into a 3-dimensional structure in the nucleus.
Current methods for studying genome-wide structure are based on proximity
ligation. However, this approach can fail to detect known structures, such as
interactions with nuclear bodies, because these DNA regions can be too far apart
to directly ligate. Accordingly, our overall understanding of genome
organization remains incomplete. Here, we develop split-pool recognition of
interactions by tag extension (SPRITE), a method that enables genome-wide
detection of higher-order interactions within the nucleus. Using SPRITE, we
recapitulate known structures identified by proximity ligation and identify
additional interactions occurring across larger distances, including two hubs of
inter-chromosomal interactions that are arranged around the nucleolus and
nuclear speckles. We show that a substantial fraction of the genome exhibits
preferential organization relative to these nuclear bodies. Our results generate
a global model whereby nuclear bodies act as inter-chromosomal hubs that shape
the overall packaging of DNA in the nucleus. Long-range chromatin interactions play critical roles in genome organization and
regulation of transcription. We now report transposase-mediated analysis of
chromatin looping (Trac-looping) for simultaneous detection of multiscale
genome-wide chromatin interactions among regulatory elements and chromatin
accessibility. With this technique, a bivalent oligonucleotide linker is
inserted between two interacting regions such that the chromatin interactions
are captured without prior chromatin fragmentation and proximity-based ligation.
Application of Trac-looping to human CD4+ T cells revealed substantial
reorganization of enhancer-promoter interactions associated with changes in gene
expression after T cell receptor stimulation. |
How many genes are screened by the FoundationOne companion diagnostic? | FoundationOne CDx comprises a 324-gene panel. | |
Interaction of WDR5 with which gene has a critical role in pancreatic cancer? | Mechanistically, WDR5 functions to sustain proper execution of DNA replication in pancreatic ductal adenocarcinoma (PDAC) cells, as previously suggested by replication stress studies involving MLL1, and c-Myc, also found to interact with WDR5. It was indeed demonstrated that interaction with c-Myc is critical for this function. | Author information:
(1)Department of Genomic Medicine, UT MD Anderson Cancer Center, Houston, TX
77030, USA; Department of Molecular and Cellular Oncology, UT MD Anderson Cancer
Center, Houston, TX 77030, USA; Department of Experimental Oncology, European
Institute of Oncology, Milan 20139, Italy. Electronic address:
[email protected].
(2)Department of Genomic Medicine, UT MD Anderson Cancer Center, Houston, TX
77030, USA; Department of Molecular and Cellular Oncology, UT MD Anderson Cancer
Center, Houston, TX 77030, USA.
(3)Institute for Applied Cancer Science, UT MD Anderson Cancer Center, Houston,
TX 77030, USA.
(4)Department of Experimental Oncology, European Institute of Oncology, Milan
20139, Italy.
(5)Department of Genomic Medicine, UT MD Anderson Cancer Center, Houston, TX
77030, USA.
(6)Sheikh Ahmed Bin Zayed Al Nahyan Center for Pancreatic Cancer Research, UT MD
Anderson Cancer Center, Houston, TX 77030, USA.
(7)Department of Epigenetics and Molecular Carcinogenesis, UT MD Anderson Cancer
Center, Houston, TX 77030, USA.
(8)Department of Experimental Oncology, European Institute of Oncology, Milan
20139, Italy; Department of Oncology and Hemato-oncology, University of Milan,
Milan 20139, Italy.
(9)Center for Genomic Science of IIT@SEMM, Istituto Italiano di Tecnologia
(IIT), Milan 20139, Italy.
(10)Department of Genomic Medicine, UT MD Anderson Cancer Center, Houston, TX
77030, USA; Institute for Applied Cancer Science, UT MD Anderson Cancer Center,
Houston, TX 77030, USA.
(11)Department of Surgical Oncology, UT MD Anderson Cancer Center, Houston, TX
77030, USA.
(12)Department of Pathology, UT MD Anderson Cancer Center, Houston, TX 77030,
USA.
(13)Department of Cancer Biology, UT MD Anderson Cancer Center, Houston, TX
77030, USA.
(14)Department of Experimental Oncology, European Institute of Oncology, Milan
20139, Italy. Electronic address: [email protected].
(15)C-4 Therapeutics, Cambridge, MA 02142, USA. Electronic address:
[email protected].
(16)Department of Genomic Medicine, UT MD Anderson Cancer Center, Houston, TX
77030, USA; Institute for Applied Cancer Science, UT MD Anderson Cancer Center,
Houston, TX 77030, USA; Department of Molecular and Cellular Oncology, UT MD
Anderson Cancer Center, Houston, TX 77030, USA. Electronic address:
[email protected]. |
Can thiotepa be recommended for treatment of osteosarcoma? | No. Thiotepa did not improve survival of patients with osteosarcoma and therefore can not be recommended for treatment of osteosarcoma. | Introduction. Osteosarcoma relapse has a poor prognosis, with less than 25%
survival at 5 years. We describe the experience of the French Society of
Paediatric Oncology (SFCE) with high dose (HD) thiotepa and autologous stem cell
transplantation (ASCT) in 45 children with relapsed osteosarcoma. Patients and
Methods. Between 1992 and 2004, 53 patients received HD thiotepa (900 mg/m(2))
followed by ASCT in 6 centres. Eight patients were excluded from analysis, and
we retrospectively reviewed the clinical radiological and anatomopathological
patterns of the 45 remaining patients. Results. Sixteen girls and 29 boys
(median age, 15.9 years) received HD thiotepa after initial progression of
metastatic disease (2), first relapse (26), and second or third relapse (17). We
report 12 radiological partial responses and 9 of 31 histological complete
responses. Thirty-two patients experienced further relapses, and 13 continued in
complete remission after surgical resection of the residual disease. Three-year
overall survival was 40%, and 3-year progression-free survival was 24%. Delay of
relapse (+/- 2 years from diagnosis) was a prognostic factor (P = 0.011). No
acute toxic serious adverse event occurred. Conclusion. The use of HD thiotepa
and ASCT is feasible in patients with relapsed osteosarcoma. A randomized study
for recurrent osteosarcoma between standard salvage chemotherapy and high dose
thiotepa with stem cell rescue is ongoing. |
What is known about aberrant proteolytic activity in disease? | Research into Alzheimer's disease pathology and treatment has often focused on presenilin proteins. These proteins provide the key catalytic activity of the γ-secretase complex in the cleavage of amyloid-β precursor protein and resultant amyloid tangle deposition. Over the last 25 years, screening novel drugs to control this aberrant proteolytic activity has yet to identify effective treatments for the disease.
Others are human skin disorders where proteolytic pathways are dysregulated. | INTRODUCTION: In the nonobese diabetic (NOD) mouse model of Sjögren's syndrome,
lymphocytic infiltration is preceded by an accumulation of dendritic cells in
the submandibular glands (SMGs). NOD mice also exhibit an increased frequency of
mature, fractalkine receptor (CX3C chemokine receptor [CX3CR]1) expressing
monocytes, which are considered to be precursors for tissue dendritic cells. To
unravel further the role played by fractalkine-CX3CR1 interactions in the
salivary gland inflammation, we studied the expression of fractalkine in NOD
SMGs.
METHODS: We studied protein expression using Western blot analysis of whole
tissue lysates. Protease activity was measured in salivary gland tissue lysates
using fluorimetric substrates. Digestive capacity of enzymes was determined by
in vitro incubation of recombit enzyme and fractalkine, followed by protein
staining and Western blot.
RESULTS: Fractalkine was detected in salivary glands of both NOD and control
mice at all ages. Western blot analysis showed fractalkine cleavage with
increasing age, which was more pronounced in NOD mice. This cleavage resulted in
a decrease in the 31 kDa form of the protein, and the generation of an
approximately 19 kDa band. Furthermore, in NOD animals older than 15 weeks, we
noted the presence of a unique approximately 17 kDa fragment. This cleavage was
organ specific, because it did not occur in brain or pancreas. Increased
gelatinase and alpha-secretase activity were detected in NOD SMG and contributed
to cleavage of the 31 kDa protein. Because aberrant cleavage products may induce
autoimmunity, we studied the presence of autoantibodies against fractalkine.
Indeed, NOD mice exhibited significantly more antibodies against fractalkine
than did control animals.
CONCLUSION: These data indicate that aberrant proteolytic activity in the NOD
SMG results in increased fractalkine cleavage and generation of a unique
fractalkine fragment. This specific cleavage may contribute to autoimmunity. Recent findings from the clinic and the laboratory have transformed the way
proteases and their inhibitors are perceived in the outermost layer of the skin,
the epidermis. It now appears that an integrated proteolytic network operates
within the epidermis, comprising more than 30 enzymes that carry out a growing
list of essential functions. Equally, defective regulation or execution of
protease-mediated processes is emerging as a key contributor to diverse human
skin pathologies, and in recent years the number of diseases attributable to
aberrant proteolytic activity has more than doubled. Here, we survey the
different roles of proteases in epidermal homeostasis (from processing enzymes
to signalling molecules) and explore the spectrum of rare and common human skin
disorders where proteolytic pathways are dysregulated. Research into Alzheimer's disease pathology and treatment has often focused on
presenilin proteins. These proteins provide the key catalytic activity of the
γ-secretase complex in the cleavage of amyloid-β precursor protein and resultant
amyloid tangle deposition. Over the last 25 years, screening novel drugs to
control this aberrant proteolytic activity has yet to identify effective
treatments for the disease. In the search for other mechanisms of presenilin
pathology, several studies have demonstrated that mammalian presenilin proteins
also act in a non-proteolytic role as a scaffold to co-localize key signaling
proteins. This role is likely to represent an ancestral presenilin function, as
it has been described in genetically distant species including non-mammalian
animals, plants, and a simple eukaryotic amoeba Dictyostelium that diverged from
the human lineage over a billion years ago. Here, we review the non-catalytic
scaffold role of presenilin, from mammalian models to other biomedical models,
and include recent insights using Dictyostelium, to suggest that this role may
provide an early evolutionary function of presenilin proteins. |
Does a comet assay measure radiation induced mutations? | Yes. The comet assay is frequently used to measure DNA damage in individual cells. | The comet assay is frequently used to measure DNA damage in individual cells. In
order to better understand the mechanisms behind the technique, we have studied
the behaviour of DNA under different electrophoresis conditions in mammalian
cells exposed to gamma radiation. The comet tails obtained after neutral
electrophoresis seem to consist of DNA loops which are attached to structures in
the nucleus, since the DNA cannot move in the second direction after
two-dimensional electrophoresis. When the DNA is labelled by a short pulse,
microautoradiography reveals that all label appear in the head of the comets
when neutral electrophoresis is applied. After chase incubation, the label moves
out into the tails. This gives further support to the view that the DNA loops
are fixed to some structure in the nucleus where also the DNA synthesis takes
place. Under alkaline electrophoresis conditions, however, the entire comet
tails move in the new electrophoresis direction. Thus, it appears that the
alkaline comet tails consist of free DNA fragments. Further, the effects of
alkaline concentration and sodium chloride during unwinding and electrophoresis
are discussed. Throughout the study, a protocol for drying and fixation of the
comets has been used. The single cell gel test (SCG-test or comet assay) is a rapid and sensitive
method for measuring DNA damage and repair in individual cells. A wide variety
of mutagens have been shown to cause DNA alterations detectable with the comet
assay, but it is not yet clear whether a relationship exists between the DNA
effects and the induction of mutations. We are therefore investigating in a cell
culture system with human cells (MRC5CV1) the induction of DNA damage by
environmental mutagens and the formation of mutations at the HPRT gene. In the
present study we investigated benzo[a]pyrene (BP), an environmental mutagenic
and carcinogenic polycyclic aromatic hydrocarbon, and its reactive metabolite
(+)-anti-benzo[a]pyrene-7,8-diol 9, 10-oxide ((+)-anti-BPDE). S9 mix activated
BP and the direct acting mutagen (+)-anti-BPDE caused a concentration-related
increase in DNA migration in the comet assay. Postincubation experiments
indicated that induced DNA effects are eliminated by DNA repair within 24 h.
BP-treatment caused a strong genotoxic effect in the comet assay but had only a
marginal effect on the frequency of gene mutations. When cells were treated with
BP in the presence of cadmium sulphate, a clear increase in genotoxicity was
observed while the effect on mutations was unchanged. Our results indicate that
DNA alterations detected with the comet assay do not necessarily relate to
mutagenesis. The absence of a close relationship between DNA migration in the
comet assay and mutagenesis may be explained by the fact that some effects seen
in the comet assay occur as a consequence of an error free DNA repair process. The alkaline single-cell gel electrophoresis (SCGE or Comet) assay appears to be
a promising tool for measuring DNA damage at the individual cell level in both
in vitro and in vivo studies. To provide further data on the possible
applicability of this assay in human biomonitoring studies, we have evaluated
the eventual genetic damage induced by therapeutic exposure to 131I, by
measuring the Comet length and the amount of DNA damage in peripheral blood
leukocytes from a group of 28 thyroid cancer patients who received 131I sodium
iodide via oral administration. Blood samples were taken just before the
treatment and 1 week after it. From the results obtained after radioiodine
therapy, a small increase in the Comet length and in the grade of DNA damage is
observed; however, this increase is not statistically significant because of
inter-individual variability and the variable responses before and after 131I
treatment. Considering our previous studies showing significant increases in the
frequency of cytogenetic damage (when measured as micronuclei) in patients
treated with relatively low doses of 131I, the results obtained in the present
work by using the Comet assay could indicate that 1 week after the exposure most
of the radioiodine-induced DNA lesions, that can be detected with this assay,
have already been repaired. BACKGROUND: In clinical radiotherapy most patients tolerate the applied dosage
with no or moderate side effects. However, 5 to 10% of all individuals show
increased acute and/or late reactions. In-vitro test systems are investigated
for their suitability for predictive purposes. This paper attempts a correlation
between the induction and repair of DNA damage measured in the comet assay and
the clinical observed reaction in order to evaluate the suitability of the comet
assay for prediction of radiation sensitivity.
PATIENTS AND METHODS: Skin fibroblasts of 30 patients with average tissue
reactions or acute and/or late increased side effects and cell lines of 4
individuals carrying the heritable disease ataxia telangiectasia (AT) were
irradiated in vitro. The induction and repair of DNA damage was measured at
different time points after irradiation in the comet assay (single cell gel
electrophoresis). These results were compared to the acute and late clinical
reactions classified according to the RTOG grading system.
RESULTS: The radiation induced DNA damage decreased over time reflecting DNA
repair. Cells of the AT individuals showed an elevated damage induction and a
reduced repair capacity compared to patients with average tissue reactions.
Fibroblasts of patients with increased acute and late side effects exhibited
slower DNA repair. In addition to the known lack of cell cycle control, our
results indicate that AT cells show reduced DNA repair capacity.
CONCLUSIONS: The comet assay seems to be able to detect some types of increased
individual radiation sensitivity. In contrast to other predictive in-vitro
tests, the comet assay needs less time and fewer cells, which would be useful in
a clinical setting. The single-cell electrophoresis (comet) assay is an established method for
measuring radiation-induced strand breaks in DNA. The extent of damage is
quantified in individual cells by assessing the intensity and distribution of a
fluorescent DNA-binding dye using image analysis software. Using the Kinetic
Imaging Komet3 system, it is demonstrated that the fluorochrome SYBR Green I
improves the resolution and sensitivity of the comet assay, particularly for
measuring radiation-induced double strand breaks. Recent in vivo and in vitro data of patients analyzed for genetic susceptibility
to radiation during cancer therapy have shown structural changes in the
chromosomes to be prevalent both in the patients being treated and in their
immediate family members. As structural changes in chromosomes frequently lead
to activation of proto-oncogenes and elimination of tumor-suppressor genes, they
represent important mechanisms for the initiation of DNA repair processes and
tumorigenesis. With the exception of rare genetic syndromes such as AT (Ataxia
telangiectasia) or NBS (Nijmegen Breakage Syndrome), the background for the
inheritance of genetic susceptibility to radiation is unknown. Recently, a
large-scale genetic screen of mouse mutants has been established within the
German Human Genome Project (Hrabè de Angelis and Balling 1998). The goal of
this ENU (ENU: ethylnitrosourea) mutagenesis screen is the generation of mutant
mice that will serve as animal models for human diseases and genetic
susceptibility. In order to fully utilize the potential of a genetic screen of
this magnitude, in which exploration for genes responsible for genomic
instability and radiation sensitivity is to occur, it is necessary to establish
a simple assay system that is amenable to automation. Hence, we are using the
single-cell gel electrophoresis (comet assay) to detect mouse mutants that
display a genetic susceptibility to ionizing radiation. We have established the
analysis parameters in the comet assay which are currently used to detect
radiation-sensitive mouse mutants and to control the variance within the mouse
population in the ENU screen. The assay can be used to isolate genes that are
responsible for DNA repair and radiation sensitivity in mouse and human. The suitability of comet assay to identify DNA damage induced by neutrons of
varying energy was tested. For this purpose, monoenergetic neutrons from
Hiroshima University Radiobiological Research Accelerator (HIRRAC) were used to
induce DNA damage in irradiated human peripheral blood lymphocytes. The level of
damage was computed as tail moment for different doses (0.125-1 Gy) and compared
with the effects resulting from irradiation with (60)Co gamma. The
neutron-irradiated cells exhibited longer comet tails consisting of tiny pieces
of broken DNA in contrast to the streaking tails generated by (60)Co gamma. The
peak biological effectiveness occurred at 0.37 and 0.57 MeV; a further increase
or decrease in neutron energy led to a reduced RBE value. The RBE values, as
measured by the comet assay, were 6.3, 5.4, 4.7, 4.3, 2.6, and 1.7 for 0.37,
0.57, 0.79, 0.186, 1, and 2.3 MeV neutrons. The lower RBE value obtained by the
comet assay when compared to that for other biological end points is discussed.
This study reports the usefulness of the alkaline comet assay for identifying
DNA damage induced by neutrons of the same radiation weighting factor. The comet
assay is a potential tool for use in neutron therapy, as well as a method for
the rapid screening of samples from individuals accidentally exposed to
radiation. The advantage of using the tobacco (Nicotiana tabacum var. xanthi) mutagenicity
assay is the ability to analyze and compare on the same plants under identical
treatment conditions both the induced acute DNA damage in somatic cells as
measured by the Comet assay and the yield of induced leaf somatic mutations.
Gamma-irradiation of tobacco seedlings induced a dose-dependent increase in
somatic mutations from 0.5 (control) to 240 per leaf (10Gy). The increased yield
of somatic mutations was highly correlated (r = 0.996) with the increased DNA
damage measured by the Comet assay immediately after irradiation. With increased
dose of gamma-irradiation, the averaged median tail moment values ( +/- S.E.)
significantly increased from 1.08 +/- 0.10 (control) to 20.26 +/- 1.61 microm
(10Gy). Nuclei isolated from leaves 24h after irradiation expressed tail moment
values that were not significantly different from the control (2.08 +/- 0.11).
Thus a complete repair of DNA damage induced by gamma-irradiation and measurable
by the Comet assay was observed, whereas the yield of somatic mutations
increased in relation to the radiation dose. Data on the kinetics of DNA repair
and of DNA damage induced by gamma-radiation on isolated tobacco nuclei, and on
nuclei isolated from irradiated leaves and roots are presented. Lymphocytes of healthy volunteers (n = 24) and of tumour patients (n = 30, 18 of
whom had experienced severe side-effects) were irradiated with x-rays in vitro.
DNA damage was analysed after 0.25-2 Gy and DNA repair after 2 Gy, and
quantification of both endpoints was done by the comet assay. The individual
differences in radiation-induced DNA damage as well as in the repair kinetics
were observed to be striking for both healthy donors and tumour patients. After
a repair time of 3 h, following 2 Gy x-irradiation, some of the healthy
volunteers showed no residual DNA damage at all in their lymphocytes, whereas
others revealed about 30%. There was no indication that our results were
affected by either age, gender or smoking habits. Slow repair kinetics and high
amounts of residual damage were characteristic for many but not all tumour
patients who had experienced severe side-effects in their normal tissues during
or after radiotherapy (n = 18). Our conclusion is that those individuals showing
poor DNA repair characteristics in the lymphocytes following in vitro
irradiation, have a high probability of being radiosensitive. The opposite
conclusion is not necessarily true: if repair is effective, this does not mean
that the individual is radioresistant, because factors other than impaired
repair may cause radiosensitivity. BACKGROUND: The neutral comet assay was devised to measure double-stranded DNA
breaks, but it has also been used to measure apoptosis based on its
characteristic DNA fragmentation patterns. There is still uncertainty about the
reliability of this method. By comparing the comet assay with a flow cytometry
method that uses Annexin V binding to apoptotic cells, we have provided further
evidence for evaluating the usefulness of the comet assay for detecting
apoptosis.
METHODS: Apoptosis was induced in human peripheral blood mononuclear cells
(PBMC) by ionizing radiation and measured using the comet assay and a flow
cytometry method that measures Annexin V and propidium iodide (PI) staining.
RESULTS: The Annexin V flow cytometry assay distinguished among early apoptosis,
late apoptosis, and an apoptotic or necrotic phase in which the cells were
labeled with both Annexin V and PI. The comet assay detected only the latter two
phases of apoptosis.
CONCLUSIONS: The comet assay is a useful tool for measuring the late stages of
apoptosis whereas the Annexin V assay measures higher amounts of apoptosis
because it can detect cells in an earlier stage of the apoptotic pathway. The relationship between deoxyribonucleic acid (DNA) damage and the cell death
induced by gamma-irradiation was examined in three kinds of cells, Chinese
hamster ovary fibroblast CHO-K1, human melanoma HMV-II and mouse leukemia
L5178Y. Cell survival was determined by a clonogenic assay. The induction and
rejoining of DNA strand breaks induced by radiation were measured by the
alkaline and neutral comet assays. L5178Y cells were the most radiosensitive,
while CHO-K1 cells and HMV-II cells were radioresistant. There was an inverse
relationship between the survival fraction at 2 Gy (SF2) and the yield of
initial DNA strand breaks per unit dose under the alkaline condition for the
comet assay, and also a relationship between SF2 and the residual DNA strand
breaks (for 4 hr after irradiation) under the neutral condition for the comet
assay, the latter being generally considered to be relative to cellular
radiosensitivity. In the present analysis, it was considered that the alkaline
condition for the comet assay was optimal for evaluating the initial DNA strand
breaks, while the neutral condition was optimal for evaluating the residual DNA
strand breaks. Since the comet assay is simpler and more rapid than other
methods for detecting radiation-induced DNA damage, this assay appears to be a
useful predictive assay for evaluating cellular clonogenic radiosensitivity of
tumor cells. Lymphoblastoid cell lines (LCL) with a heterozygous mutation in the breast
cancer susceptibility gene BRCA1 have been repeatedly used to elucidate the
biological consequences of such a mutation with respect to radiation sensitivity
and DNA repair deficiency. Our previous results indicated that LCL with a BRCA1
mutation do not generally show the same chromosomal mutagen sensitivity in the
micronucleus test as lymphocytes with the same BRCA1 mutation. To further study
the radiosensitivity of LCL with a BRCA1 mutation, we now performed comparative
investigations with the alkaline (pH 13) and the neutral (pH 8.3) comet assay
and pulsed field gel electrophoresis (PFGE). These tests are commonly used to
determine the repair capacity for DNA double strand breaks (DNA-DSB). Six LCL
(three established from women with a heterozygous BRCA1 mutation and three from
healthy controls) were investigated. Induction (2 and 5 Gy) of gamma-ray-induced
DNA damage and its repair (during 60 min after irradiation) was measured with
the alkaline and neutral comet assay. Comparative experiments were performed
with PFGE determining the induction of DNA-DSB by 10-50 Gy gamma-irradiation and
their repair during 6 h. There was no significant difference between LCL with
and without BRCA1 mutation in any of these experiments. Therefore, using these
methods, no indication for a delayed repair of DNA-DSB in LCL with a BRCA1
mutation was found. However, these results do not generally exclude DNA-DSB
repair deficiency in these cell lines because the methods applied have limited
sensitivity and only measure the speed but not the fidelity of the repair
process. The alkaline version of single cell gel electrophoresis (comet) assay is widely
used for evaluating DNA damage at the individual cell level. The standard
alkaline method of the comet assay involves deproteinization of cells embedded
in agarose gel using a high salt-detergent lysis buffer, followed by
denaturation of DNA and electrophoresis using a strong alkali at pH>13 [N.P.
Singh, M.T. McCoy, R.R. Tice, E.L. Schneider, A simple technique for
quantitation of low levels of DNA damage in individual cells, Exp. Cell. Res.
175 (1988) 184-191]. However, a recent report showed that a strong alkali
treatment results in simultaneous deproteinization of cells and denaturation of
genomic DNA [P. Sestili, C. Martinelli, V. Stocchi, The fast halo assay: an
improved method to quantify genomic DNA strand breakage at the single
cell-level, Mutat. Res. 607 (2006) 205-214]. This study was carried out to test
whether the strong alkali deproteinization of cells could replace the high
salt-detergent lysis step used in the standard method of the alkaline comet
assay. Peripheral blood lymphocytes from 3 healthy individuals were irradiated
with gamma rays at doses varying between 0 and 10 Gy. Following irradiation, the
comet assay was performed according to the standard alkaline method (pH>13) and
a modified method. In the modified method, agarose embedded cells were treated
with a strong alkali (0.3M NaOH, 0.02 M Trizma and 1mM EDTA, pH>13) for 20 min
to allow deproteinization of cells and denaturation of DNA. This was followed by
electrophoresis using the same alkali solution to obtain comets. DNA damage
expressed in terms of comet tail length, percentage of DNA in comet tail and
tail moment obtained by the standard alkaline method and the modified method
were compared. In both methods, DNA damage showed a good correlation with the
dose of gamma ray. The results indicate a satisfactory sensitivity of the
modified method in detecting radiation-induced DNA damage in human peripheral
blood lymphocytes. Phototherapy (PT) is the most widely used form of treatment for unconjugated
hyperbilirubinemia. One possible harmful consequence of PT is of a genetic
nature. High levels of bilirubin may lead to oxidative damage in newborns:
photochemical reactions may produce toxic photoproducts, probably peroxides. In
order to investigate this hypothesis further under in vivo conditions, DNA
strand-break frequency was examined by means of the comet assay in peripheral
lymphocytes of icteric newborns undergoing PT treatment, and the levels of
catalase, an antioxidant enzyme, were determined. We analyzed 20 term
non-hemolitic hyperbilirubinemic jaundiced neonates before PT ('before PT'
group) and just prior to ending PT ('after PT' group) and compared comet scores
of these patients with those of 20 healthy term neonates who all had bilirubin
levels in the physiological range. Comet scores (tail length, tail moment and
%DNA in tail) of the group 'before phototherapy' were 23.5 +/- 16.3, 7.41
(0.97-40.7), 33.0 +/- 12.1, respectively and scores of after phototherapy group
were 3.2 +/- 1.8, 0.29 (0.3-3.2), 10.7 +/- 3.7, respectively. Comet scores of
the control group were 3.0 +/- 2.9, 0.25 (0.03-3.22), 10.9 +/- 4.5,
respectively. Comet scores and plasma catalase activities in hyperbilirubinemic
newborns were significantly higher before phototherapy, compared with the values
after phototherapy and in the control groups (p < 0.001). There was no
statistical difference between the 'after phototherapy' group and the controls
(p > 0.05). These results indicate that high serum bilirubin level has genotoxic
effects as is evident from the high rate of DNA strand-breaks in jaundiced
newborns. Also PT does not cause an increase in DNA oxidation or induce the
genotoxic effects of bilirubin. The counteracting effect of higher catalase
activities in hyperbilirubinemic newborns may be responsible for the
inactivating toxic and DNA-damaging effects of PT. The COMET assay is recognized as a rapid and sensitive method in quantifying
radiation induced DNA damage. We investigated the distorting influence of
endogenous, assay-inherent factors onto base (single cell level) and primary
outcome measures (experimental/slide level), such as olive tail moment (OTM) and
percentage DNA in the tail (%tail-DNA). From 2003 to 2008, we performed the
assay on lymphocytes isolated from the blood samples of 355 lung cancer
patients, 170 controls, and 610 relatives, as well as one single reference
individual, repeated 170 times. In total, the data from 10,016 single
experiments containing around 1,750,000 cells have been included in this study.
This is the first time that the endogenous variability of the COMET assay has
been validated systematically on such a huge data set over a 5 year period.
Assuming that the reference sample reflects assay specific white noise, we
estimated a proportion of 7-95% of the variability of the outcome measures due
to assay variation (white noise) depending on parameter, exposure level, and
study group. The proportion of white noise was largest for the initial radiation
damage. The specific endogenous factors considered attribute to 14.8% of the
total variability in the primary outcome measurements of the OTM and 6.9% of the
%tail-DNA. OTM turns out to be a sensitive parameter to detect variation, but is
also more susceptible to disturbance caused by endogenous factors than
%tail-DNA. To reduce the experimental variability in COMET assays, we recommend
a highly standardized operation protocol as well as inspecting and/or adjusting
the primary outcome measures according to endogenous factors before calculating
secondary outcome measures, e.g. DNA repair capacity (DRC) or testing
statistical inference. A human reference (HR) sample is also useful to inspect
homogeneity in the temporal progression of long lasting investigations, but not
for calibrating primary outcome measurements. Ionizing radiation is known to induce genetic damage in diverse groups of
organisms. Under accidental situations, large quantities of radioactive elements
get released into the environment and radiation emitted from these radionuclides
may adversely affect both the man and the non-human biota. The present study is
aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna
employing two species of selected bivalves, (b) to evaluate the possible use of
'Comet assay' for detecting genetic damage in haemocytes of bivalves as a
biomarker for environmental biomonitoring and also (c) to compare the relative
sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta
to gamma radiation. The comet assays was optimized and validated using different
concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a
direct-acting reference genotoxic agent, to which the bivalves were exposed for
various times (24, 48 and 72 h). Bivalves were irradiated (single acute
exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation
and their genotoxic effects on the haemocytes were studied using the comet
assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of
both EMS-exposed and irradiated bivalves and comet assay was carried out using
standard protocol. A significant increase in DNA damage was observed as
indicated by an increase in % tail DNA damage at different concentrations of EMS
and all the doses of gamma radiation as compared to controls in both bivalve
species. This showed a dose-dependent increase of genetic damage induced in
bivalves by EMS as well as gamma radiation. Further, the highest DNA damage was
observed at 24h. The damage gradually decreased with time, i.e. was smaller at
48 and 72 h than at 24h post irradiation in both species of bivalves. This may
indicate repair of the damaged DNA and/or loss of heavily damaged cells as the
post irradiation time advanced. The present study reveals that gamma radiation
induces single strand breaks in DNA as measured by alkaline comet assay in
bivalves and comet assay serves as a sensitive and rapid method to detect
genotoxicity of gamma radiation. This study further indicates that both M. casta
and P. malabarica exhibit almost identical sensitivity to gamma radiation as
measured by DNA damage. Evaluation of primary DNA-damage is one way to identify potential genotoxic
agents and for this purpose the Comet assay has, for the last decades, been used
to monitor DNA single strand and double strand breaks in individual cells.
Various attempts have been made to modify the different steps in the in vitro
protocol for the Comet assay in order to improve its sensitivity. However, to
the best of our knowledge, nobody has tried to replace the traditionally used
NaOH-based electrophoresis solution (pH > 13), with another type of solution. In
the present paper, using TK-6 cells exposed to different concentrations of H2O2
or ionizing radiation, we present evidence clearly showing that a low-conductive
LiOH-based electrophoresis solution at pH 12.5, and a more gentle lysis
procedure, significantly improved both the speed and sensitivity of the assay.
The new approach, which we call the Flash-comet, is based on a lysis buffer at
pH 8.5, an unwinding time of 2.5 min in a LiOH solution without EDTA at pH 12.5,
and an electrophoresis time of 1 min at 150 V (5 V/cm) using the same solution. |
What is formative pluripotency? | Formative pluripotency features a gene regulatory network switch from the nave state. Two phases of pluripotency, called nave and primed, have previously been described. | In the mouse blastocyst, epiblast cells are newly formed shortly before
implantation. They possess a unique developmental plasticity, termed naive
pluripotency. For development to proceed, this naive state must be subsumed by
multi-lineage differentiation within 72 h following implantation. In vitro
differentiation of naive embryonic stem cells (ESCs) cultured in controlled
conditions provides a tractable system to dissect and understand the process of
exit from naive pluripotency and entry into lineage specification. Exploitation
of this system in recent large-scale RNAi and mutagenesis screens has uncovered
multiple new factors and modules that drive or facilitate progression out of the
naive state. Notably, these studies show that the transcription factor network
that governs the naive state is rapidly dismantled prior to upregulation of
lineage specification markers, creating an intermediate state that we term
formative pluripotency. Here, we summarize these findings and propose a road map
for state transitions in ESC differentiation that reflects the orderly dynamics
of epiblast progression in the embryo. The enhancer landscape of pluripotent stem cells undergoes extensive
reorganization during early mammalian development. The functions and mechanisms
behind such reorganization, however, are unclear. Here, we show that the
transcription factor GRHL2 is necessary and sufficient to activate an epithelial
subset of enhancers as naive embryonic stem cells (ESCs) transition into
formative epiblast-like cells (EpiLCs). Surprisingly, many GRHL2 target genes do
not change in expression during the ESC-EpiLC transition. Instead, enhancers
regulating these genes in ESCs diminish in activity in EpiLCs while
GRHL2-dependent alternative enhancers become activated to maintain
transcription. GRHL2 therefore assumes control over a subset of the naive
network via enhancer switching to maintain expression of epithelial genes upon
exit from naive pluripotency. These data evoke a model where the naive
pluripotency network becomes partitioned into smaller, independent networks
regulated by EpiLC-specific transcription factors, thereby priming cells for
lineage specification. |
Has the companion diagnostic HercepTest received FDA approval? | Yes, the HercepTest has received FDA approval. | |
Which R/Bioconductor package has been developed for visualizing differential amino acid group usage in proteomics? | DagLogo is an R/Bioconductor package for identifying and visualizing differential amino acid group usage in proteomics data. DagLogo allows various formats for input sets and provides comprehensive options to build optimal background models. It implements different reduced AA alphabets to group AAs of similar properties. Furthermore, dagLogo provides statistical and visual solutions for differential AA (or AA group) usage analysis of both large and small data sets. Case studies showed that dagLogo can better identify and visualize conserved protein sequence patterns from different types of inputs and can potentially reveal the biological patterns that could be missed by other logo generators. | |
Dasatinib and Blinatumomab are used for treatment of which disease? | Dasatinib and Blinatumomab produces molecular responses in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. | Liposomal vincristine is designed to reduce neurotoxicity and increase dose
intensity delivery, and has been approved as salvage therapy in
relapsed/refractory acute lymphoblastic leukemia (ALL). Our aim was to evaluate
the response rate, toxicities, and outcome of adults with newly diagnosed ALL
who received liposomal vincristine, rather than regular vincristine in
combination with intensive chemotherapy (Hyper-CMAD). In a single-center, phase
2 study, patients ≥18 years with newly-diagnosed B-cell ALL were eligible to
receive hyper-CMAD alternating with high-dose methotrexate and cytarabine.
Rituximab was administered in CD20 positive ALL. Tyrosine kinase inhibitors
(imatinib or dasatinib) were added in Philadelphia chromosome-positive
(Ph-positive) ALL. Thirty-one patients were enrolled, median follow-up of
59 months (0.3-70). Thirteen patients (42%) had CD20 positive ALL, and 21 (68%)
had Ph-positive ALL. Thirty (97%) achieved complete remission (CR). All 26
patients with abnormal karyotype achieved complete cytogenetic response (CCyR),
and 27/30 (90%) achieved negative minimal residual disease status by multicolor
flow cytometry. Of 20 evaluable Ph-positive ALL patients, major molecular
response (MMR) was achieved in 19 patients (95%); complete molecular response
(CMR) in 14 (70%). Grade 3/4 peripheral neuropathy was observed in five (16%)
with all grade peripheral neuropathy in 21 (68%). With a median follow-up of
59 months, 21 (68%) patients are alive. The 5-year CR duration and survival
rates were 73% and 61%, respectively. Ten (32%) patients died: one, sepsis on
C1D10; four, unknown; one, post-transplant complications; four, relapse.
Hyper-CMAD with liposomal vincristine is safe and demonstrated high response and
survival rates in newly diagnosed ALL. Improving survival outcomes in adult B-cell acute lymphoblastic leukemia (B-ALL)
remains a clinical challenge. Relapsed disease has a poor prognosis despite the
use of tyrosine kinase inhibitors (TKIs) for Philadelphia chromosome positive
(Ph+ ALL) cases and immunotherapeutic approaches, including blinatumomab and
chimeric antigen receptor T cells. Targeting aberrant cell survival pathways
with selective small molecule BH3-mimetic inhibitors of BCL-2 (venetoclax,
S55746), BCL-XL (A1331852), or MCL1 (S63845) is an emerging therapeutic option.
We report that combined targeting of BCL-2 and MCL1 is synergistic in B-ALL in
vitro. The combination demonstrated greater efficacy than standard
chemotherapeutics and TKIs in primary samples from adult B-ALL with Ph+ ALL,
Ph-like ALL, and other B-ALL. Moreover, combined BCL-2 or MCL1 inhibition with
dasatinib showed potent killing in primary Ph+ B-ALL cases, but the BH3-mimetic
combination appeared superior in vitro in a variety of Ph-like ALL samples. In
PDX models, combined BCL-2 and MCL1 targeting eradicated ALL from Ph- and Ph+
B-ALL cases, although fatal tumor lysis was observed in some instances of high
tumor burden. We conclude that a dual BH3-mimetic approach is highly effective
in diverse models of high-risk human B-ALL and warrants assessment in clinical
trials that incorporate tumor lysis precautions. BACKGROUND: Outcomes in patients with Philadelphia chromosome (Ph)-positive
acute lymphoblastic leukemia (ALL) have improved with the use of tyrosine kinase
inhibitors. Molecular remission is a primary goal of treatment.
METHODS: We conducted a phase 2 single-group trial of first-line therapy in
adults with newly diagnosed Ph-positive ALL (with no upper age limit). Dasatinib
plus glucocorticoids were administered, followed by two cycles of blinatumomab.
The primary end point was a sustained molecular response in the bone marrow
after this treatment.
RESULTS: Of the 63 patients (median age, 54 years; range, 24 to 82) who were
enrolled, a complete remission was observed in 98%. At the end of dasatinib
induction therapy (day 85), 29% of the patients had a molecular response, and
this percentage increased to 60% after two cycles of blinatumomab; the
percentage of patients with a molecular response increased further after
additional blinatumomab cycles. At a median follow-up of 18 months, overall
survival was 95% and disease-free survival was 88%; disease-free survival was
lower among patients who had an IKZF1 deletion plus additional genetic
aberrations (CDKN2A or CDKN2B, PAX5, or both [i.e., IKZF1 plus]). ABL1 mutations
were detected in 6 patients who had increased minimal residual disease during
induction therapy, and all these mutations were cleared by blinatumomab. Six
relapses occurred. Overall, 21 adverse events of grade 3 or higher were
recorded. A total of 24 patients received a stem-cell allograft, and 1 death was
related to transplantation (4%).
CONCLUSIONS: A chemotherapy-free induction and consolidation first-line
treatment with dasatinib and blinatumomab that was based on a targeted and
immunotherapeutic strategy was associated with high incidences of molecular
response and survival and few toxic effects of grade 3 or higher in adults with
Ph-positive ALL. (Funded by Associazione Italiana per la Ricerca sul Cancro and
others; GIMEMA LAL2116 D-ALBA EudraCT number, 2016-001083-11; ClinicalTrials.gov
number, NCT02744768.). A phase II trial shows that a chemotherapy-free regimen of dasatinib and
blinatumomab produces molecular responses in patients with Philadelphia
chromosome-positive acute lymphoblastic leukemia. The study found that 60% of
patients had molecular responses after two cycles of blinatumomab and 71% had
molecular responses after five cycles. |
Is phosphoenolpyruvate carboxykinase 1 (PCK1) the rate-limiting enzyme in gluconeogenesis? | Yes, Pck1 is a rate-limiting gluconeogenic enzyme, where its deficiency or mutation contributes to serious clinical situations as neonatal hypoglycemia and liver failure. | Gluconeogenesis, the reverse process of glycolysis, is a favorable mechanism at
conditions of glucose deprivation. Pck1 is a rate-limiting gluconeogenic enzyme,
where its deficiency or mutation contributes to serious clinical situations as
neonatal hypoglycemia and liver failure. A recent report confirms that Pck1 is a
target for proteasomal degradation through its proline residue at the
penultimate position, recognized by Gid4 E3 ligase, but with a lack of
informative structural details. In this study, we delineate the localized
sequence motif, degron, that specifically interact with Gid4 ligase and unravel
the binding mode of Pck1 to the Gid4 ligase by using molecular docking and
molecular dynamics. The peptide/protein docking HPEPDOCK web server along with
molecular dynamic simulations are applied to demonstrate the binding mode and
interactions of a Pck1 wild type (SPSK) and mutant (K4V) with the recently
solved structure of Gid4 ligase. Results unveil a distinct binding mode of the
mutated peptide compared with the wild type despite having comparable binding
affinities to Gid4. Moreover, the four-residue peptide is found insufficient for
Gid4 binding, while the seven-residue peptide suffices for binding to Gid4. The
amino acids S134, K135, and N137 in the loop L1 (between β1 and β2) of the Gid4
are essential for the stabilization of the seven-residue peptide in the binding
site of the ligase. The presence of Val4 instead of Lys4 smashes the H-bonds
that are formed between Lys4 and Gid4 in the wild type peptide, making the
peptide prone to bind with the other side of the binding pocket (L4 loop of
Gid4). The dynamics of Gid4 L3 loop is affected dramatically once K4V mutant
Pck1 peptide is introduced. This opens the door to explore the mutation effects
on the binding mode and smooth the path to target protein degradation by design
competitive and non-competitive inhibitors. BACKGROUND: Phosphoenolpyruvate carboxykinase (PEPCK) is a metabolic enzyme in
the gluconeogenesis pathway, where it catalyzes the reversible conversion of
oxaloacetate (OAA) to phosphoenolpyruvate (PEP) and CO2. The substrates for
Escherichia coli PEPCK are OAA and MgATP, with Mn2+ acting as a cofactor.
Analysis of PEPCK structures have revealed amino acid residues involved in
substrate/cofactor coordination during catalysis.
METHODS: Key residues involved in coordinating the different substrates and
cofactor bound to E. coli PEPCK were mutated. Purified mutant enzymes were used
for kinetic assays. The structure of some mutant enzymes were determined using
X-ray crystallography.
RESULTS: Mutation of residues D269 and H232, which comprise part of the
coordination sphere of Mn2+, reduced kcat by 14-fold, and significantly
increased the Km values for Mn2+ and OAA. Mutation of K254 a key residue in the
P-loop motif that interacts with MgATP, significantly elevated the Km value for
MgATP and reduced kcat. R65 and R333 are key residues that interacts with OAA.
The R65Q and R333Q mutations significantly increased the Km value for OAA and
reduced kcat respectively.
CONCLUSIONS: Our results show that mutation of residues involved in coordinating
OAA, MgATP and Mn2+ significantly reduce PEPCK activity. K254 plays an important
role in phosphoryl transfer, while R333 is involved in both OAA decarboxylation
and phosphoryl transfer by E. coli PEPCK.
GENERAL SIGNIFICANCE: In higher organisms including humans, PEPCK helps to
regulate blood glucose levels, hence PEPCK is a potential drug target for
patients with non-insulin dependent diabetes mellitus. The proteolytic cleavage of Fibronectin type III domain-containing 5 (FNDC5)
generates soluble irisin. Initially described as being mainly produced in muscle
during physical exercise, irisin mediates adipose tissue thermogenesis and also
regulates carbohydrate and lipid metabolism. The aim of this study was to
evaluate the hepatic expression of FNDC5 and its role in hepatocytes in
Non-Alcoholic Fatty Liver (NAFL). Here we report that hepatic expression of
FNDC5 increased with hepatic steatosis and liver injury without impacting the
systemic level of irisin in mouse models of NAFLD (HFD and MCDD) and in obese
patients. The increased Fndc5 expression in fatty liver resulted from its
upregulation in hepatocytes and non-parenchymal cells in mice. The local
production of Fndc5 in hepatocytes was influenced by genotoxic stress and
p53-dependent pathways. The down-regulation of FNDC5 in human HepG2 cells and in
primary mouse hepatocytes increased the expression of PEPCK, a key enzyme
involved in gluconeogenesis associated with a decrease in the expression of
master genes involved in the VLDL synthesis (CIDEB and APOB). These alterations
in FNDC5-silenced cells resulted to increased steatosis and insulin resistance
in response to oleic acid and N-acetyl glucosamine, respectively. The
downregulation of Fndc5 also sensitized primary hepatocytes to apoptosis in
response to TNFα, which has been associated with decreased hepatoprotective
autophagic flux. In conclusion, our human and experimental data strongly suggest
that the hepatic expression of FNDC5 increased with hepatic steatosis and its
upregulation in hepatocytes could dampen the development of NAFLD by negatively
regulating steatogenesis and hepatocyte death. Author information:
(1)Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., 1-16-13
Kita-Kasai, Edogawa-ku, Tokyo 134-8630, Japan. Electronic address:
[email protected].
(2)Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., 1-16-13
Kita-Kasai, Edogawa-ku, Tokyo 134-8630, Japan. Electronic address:
[email protected].
(3)Biomarker & Translational Research Department, Daiichi Sankyo Co., Ltd.,
1-2-58, Hiromachi, Shinagawa-ku, Tokyo 140-0005, Japan. Electronic address:
[email protected].
(4)Biomarker & Translational Research Department, Daiichi Sankyo Co., Ltd.,
1-2-58, Hiromachi, Shinagawa-ku, Tokyo 140-0005, Japan. Electronic address:
[email protected].
(5)Oncology Research Laboratories I, Daiichi Sankyo Co., Ltd., 1-2-58,
Hiromachi, Shinagawa-ku, Tokyo 140-0005, Japan. Electronic address:
[email protected].
(6)Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., 1-16-13
Kita-Kasai, Edogawa-ku, Tokyo 134-8630, Japan. Electronic address:
[email protected].
(7)Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., 1-16-13
Kita-Kasai, Edogawa-ku, Tokyo 134-8630, Japan. Electronic address:
[email protected].
(8)Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., 1-16-13
Kita-Kasai, Edogawa-ku, Tokyo 134-8630, Japan. Electronic address:
[email protected]. Author information:
(1)School of Pharmacy, Tianjin Medical University, Tianjin Key Laboratory on
Technologies Enabling Development Clinical Therapeutics and Diagnostics
(Theragnostic), Tianjin, People's Republic of China.
(2)School of Pharmacy, Tianjin Medical University, Tianjin Key Laboratory on
Technologies Enabling Development Clinical Therapeutics and Diagnostics
(Theragnostic), Tianjin, People's Republic of China; Department of Pharmacy,
Tianjin Children's Hospital, People's Republic of China.
(3)Department of Immunology, Key Laboratory of Immune Microenvironment and
Disease of the Educational Ministry of China, People's Republic of China.
(4)School of Pharmacy, Tianjin Medical University, Tianjin Key Laboratory on
Technologies Enabling Development Clinical Therapeutics and Diagnostics
(Theragnostic), Tianjin, People's Republic of China; Research Center of Basic
Medical Sciences, Tianjin Medical University, Tianjin, People's Republic of
China. Electronic address: [email protected].
(5)School of Pharmacy, Tianjin Medical University, Tianjin Key Laboratory on
Technologies Enabling Development Clinical Therapeutics and Diagnostics
(Theragnostic), Tianjin, People's Republic of China. Electronic address:
[email protected]. |
What conditions are diagnosed using the scratch collapse test? | Scouring collapse test is used for the diagnosis of cts, cubital tunnel syndrome and carpal tunnel syndrome. | BACKGROUND: The scratch collapse test is a recently described provocative test
for diagnosis of peripheral nerve compression.
METHODS: The scratch collapse test was studied prospectively in 24 consecutive
patients with a diagnosis of common peroneal nerve compression neuropathy. The
diagnosis was confirmed by history, physical examination, and electrodiagnostic
testing. Provocative testing by the scratch collapse test and Tinel's sign was
performed.
RESULTS: The scratch collapse test showed a sensitivity of 0.77 and a
specificity of 0.99, while the Tinel's sign showed 0.65 and 0.99, respectively.
CONCLUSION: The scratch collapse test is a sensitive and specific provocative
test that compares favorably to existing clinical tests and aids in the
diagnosis of common peroneal neuropathy.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, II. The utility of the scratch collapse test has been demonstrated in examination of
patients with carpal and cubital tunnel syndromes and long thoracic and peroneal
nerve compressions. In the authors' clinic, this lesser known test plays a key
role in peripheral nerve examination where localization of the nerve irritation
or injury is not fully understood. Test utility and accuracy in patients with
more challenging presentations likely correlate with tester understanding and
experience. This article offers a clear outline of all stages of the test to
improve interrater reliability. The nuances of test performance are described,
including a description of situations where the scratch collapse test is deemed
inappropriate. Four clinical scenarios where the scratch collapse test may be
useful are included. Corresponding video content is provided to improve
performance and interpretation of the scratch collapse test.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, V. BACKGROUND: Despite the fact that carpal tunnel syndrome (CTS) is the most
common entrapment neuropathy, the diagnostic accuracy of clinical screening
examinations for CTS is controversial. The scratch collapse test (SCT) is a
novel test that may be of diagnostic advantage. The purpose of our study was to
determine the diagnostic accuracy of the SCT for CTS.
METHODS: A literature search was performed using PubMed (1966 to April 2018);
Ovid MEDLINE (1966 to April 2018); EMBASE (1988 to April 2018); and Cochrane
Central Register of Controlled Trials (The Cochrane Library, to April 2018). We
examined the studies for the pooled sensitivity, specificity, and likelihood
ratios of the SCT. This review has been registered with PROSPERO
(CRD42018077115).
RESULTS: The literature search generated 13 unique articles. Seven articles were
included for full text screening and 3 articles met our inclusion criteria, all
of which were level II evidence with low risk of bias (165 patients). Pooled
sensitivities, specificities, positive likelihood ratio, and negative likelihood
ratios were 0.32 [95% CI (0.24-0.41)], 0.62 [95% CI (0.45-0.78)], 0.75 [95% CI
(0.33-1.67)], and 1.03 [95% CI (0.61-1.74)], respectively. The calculated area
under the summary receiver operating characteristic (AUSROC) curve was 0.25,
indicating a low diagnostic accuracy.
CONCLUSION: The SCT has poor sensitivity; however, it is moderately specific.
Based on the current literature and their variable quality of the evidence, we
conclude that the SCT is not an adequate screening test for detecting CTS. PURPOSE: To clarify the sensitivity, specificity, and interrater reliability of
the scratch collapse test for carpal tunnel syndrome (CTS) and cubital tunnel
syndrome, using blinded observers in a general patient population.
METHODS: Ninety-two subjects were recruited from all patients referred for
electrodiagnostic studies for upper extremity symptoms that were thought to be
related to an entrapment mononeuropathy. The scratch collapse test was performed
twice on each patient, once by the resident and once by a nerve conduction
technician. Both observers were blinded to all aspects of the patient's
presentation. Sensitivity and specificity for the scratch collapse test were
calculated twice, once using electrodiagnostic testing results and a second time
using a validated clinical tool (the CTS-6) as the reference standard. The
interrater reliability was also calculated.
RESULTS: Using electrodiagnostic criteria as a reference standard, the scratch
collapse test had a sensitivity of 7% and a specificity of 78% for CTS. Using
clinical criteria as a reference standard, the test had a sensitivity of 15% and
a specificity of 87%. For cubital tunnel syndrome, the sensitivity was 10% and
the specificity was 90%. For the resident/technician 1, kappa was -0.025 (worse
than chance alone). For the resident/technician 2, kappa was 0.211 (fair
strength of agreement).
CONCLUSIONS: The sensitivity of the scratch collapse test for CTS and cubital
tunnel syndrome was lower than that found in other studies, regardless of
whether a clinical or an electrodiagnostic reference standard was used. The
specificity was high. Overall interrater agreement was lower than previously
reported. These results call into question the sensitivity and interrater
reliability of the scratch collapse test for CTS and cubital tunnel syndrome.
TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II. Background: The scratch collapse test (SCT) is a clinical examination maneuver
that has been previously reported as a reliable and reproducible test to
diagnose carpal tunnel syndrome (CTS). The initial study by Cheng et al in 2008
showed a simple test with high sensitivity. However, subsequent attempts to
reproduce those findings have resulted in lower accuracy. Our goal was to
evaluate the use of the SCT for patients presenting with symptoms of pain,
numbness, or weakness in an upper extremity. Methods: Forty patients were
referred to the electrodiagnostic (EDX) lab for evaluation of an upper
extremity. One blinded examiner who was familiar with the maneuver performed the
SCT on all 40 patients. Another physician or technician performed the nerve
conduction study and electromyography. Patient history and accompanying physical
examination findings were not revealed to the SCT examiner. Results: The
relationship between the SCT performed by a blinded examiner and the EDX
performed by blinded examiners was nonsignificant (P = .676) and showed a
sensitivity of 0.48, specificity of 0.59, positive predictive value of 0.61, and
negative predictive value of 0.45. Conclusion: Based on this study and previous
findings by other authors, we would advise against the use of the SCT in CTS for
important patient-care decisions, such as surgical decision-making, until future
research is done. It is possible that the SCT, in combination with other
physical examination maneuvers, could increase diagnostic accuracy and enhance
patient management. The diagnosis of nerve compression relies on collecting diagnostic clues from
the history, physical examination, imaging and diagnostic testing. There are
several provocative tests to aid in the diagnosis of nerve compression. The
'Scratch Collapse Test' (SCT) has emerged as a new provocative test to assist in
the localisation of peripheral nerve compression. This study aims to perform a
systematic review of literature to assess the data on the reliability of the SCT
as a diagnostic test for entrapment neuropathy. Ten articles were reviewed. Five
articles had sufficient numerical data for analysis, and in these five articles,
the positive predictive values and specificity were high, i.e. between 0.71 and
0.99 and 0.6 and 0.99, respectively, whereas other values were very variable,
i.e. individual negative predictive values ranged from 0.15 to 0.92 and the
sensitivity values ranged from 0.24 to 0.77. Another main finding was the
versatility of the test in that it can be used for various nerve entrapments and
to localise the exact level of compression. Literature suggests that SCT has
potential to be used as a clinical diagnostic tool for entrapment neuropathy.
However, wide variations in early literature suggest that SCT should not be used
as a sole diagnostic tool but as an adjunct to a surgeon's diagnostic
repertoire. |
Which is the main gene signature in Systemic Lupus Erythematosus (SLE)? | Systemic Lupus Erythematosus (SLE) has a type I interferon (IFN) gene signature. | Systemic lupus erythematosus (SLE) is a prototype systemic autoimmune disease
characterized by flares of high morbidity. Using oligonucleotide microarrays, we
now show that active SLE can be distinguished by a remarkably homogeneous gene
expression pattern with overexpression of granulopoiesis-related and interferon
(IFN)-induced genes. Using the most stringent statistical analysis (Bonferroni
correction), 15 genes were found highly up-regulated in SLE patients, 14 of
which are targets of IFN and one, defensin DEFA-3, a major product of immature
granulocytes. A more liberal correction (Benjamini and Hochberg correction)
yielded 18 additional genes, 12 of which are IFN-regulated and 4
granulocyte-specific. Indeed immature neutrophils were identified in a large
fraction of SLE patients white blood cells. High dose glucocorticoids, a
standard treatment of disease flares, shuts down the interferon signature,
further supporting the role of this cytokine in SLE. The expression of 10 genes
correlated with disease activity according to the SLEDAI. The most striking
correlation (P < 0.001, r = 0.55) was found with the formyl peptide
receptor-like 1 protein that mediates chemotactic activities of defensins.
Therefore, while the IFN signature confirms the central role of this cytokine in
SLE, microarray analysis of blood cells reveals that immature granulocytes may
be involved in SLE pathogenesis. Recent studies of patients with systemic lupus erythematosus, together with data
from lupus-prone mice, suggest that inappropriate activation of type I
interferon might have a role in disease pathogenesis. Serum levels of IFN-alpha
are elevated in SLE patients, and gene expression profiling of peripheral blood
cells shows that most lupus cases demonstrate an upregulation of IFN-responsive
genes. Of interest, the IFN gene 'signature' correlates with more severe
disease. The available data support a model whereby chromatin-containing immune
complexes circulating in the blood of lupus patients stimulate leukocytes to
produce IFN, which perpetuates disease. These emerging insights into the
connection between IFN and lupus provide a host of new diagnostic and
therapeutic opportunities. To date, the pathogenesis of systemic lupus erythematosus (SLE) is only
partially understood. A characteristic feature of this disease is the occurrence
of antibodies against nuclear antigens. Further, SLE is characterized by a
type-I interferon gene signature. A dysregulation of apoptosis and phagocytosis
of apoptotic cells is discussed as a central pathogenetic mechanism in the
development of SLE. Several publications in recent years have described an
accumulation of autoantigens within apoptotic cells, as well as an exposition of
these antigens on the surface of apoptotic cells. During late stages of
apoptosis, autoantigens are posttranslationally modified, leading to the
formation of neoantigens. Subcellular fragments such as apoptotic microparticles
also seem to be involved in the pathogenesis of SLE. It has been shown that
microparticles contain relevant antigens and stimulate B- and T-lymphocytes.
Moreover, apoptotic microparticles have the ability to stimulate plasmacytoid
dendritic cells, causing a secretion of interferon alpha. These observations
provide a link between dysregulation of apoptosis and phagocytosis and the
type-I interferon signature observed in SLE patients. OBJECTIVE: Type I interferons (IFNs) play an important role in the pathogenesis
of systemic lupus erythematosus (SLE). This phase Ia trial was undertaken to
evaluate the safety, pharmacokinetics, and immunogenicity of anti-IFNalpha
monoclonal antibody (mAb) therapy in SLE. During the trial, we also examined
whether overexpression of an IFNalpha/beta-inducible gene signature in whole
blood could serve as a pharmacodynamic biomarker to evaluate IFNalpha
neutralization and investigated downstream effects of neutralizing IFNalpha on
BAFF and other key signaling pathways, i.e., granulocyte-macrophage
colony-stimulating factor (GM-CSF), interleukin-10 (IL-10), tumor necrosis
factor alpha (TNFalpha), and IL-1beta, in SLE.
METHODS: Affymetrix Human Genome U133 Plus 2.0 microarrays were used to profile
whole blood and lesional skin of patients receiving standard therapy for mild to
moderate SLE. Selected IFNalpha/beta-inducible proteins were analyzed by
immunohistochemistry.
RESULTS: With the study treatment, we observed anti-IFNalpha mAb-specific and
dose-dependent inhibition of overexpression of IFNalpha/beta-inducible genes in
whole blood and skin lesions from SLE patients, at both the transcript and the
protein levels. In SLE patients with overexpression of messenger RNA for BAFF,
TNFalpha, IL-10, IL-1beta, GM-CSF, and their respective inducible gene
signatures in whole blood and/or skin lesions, we observed a general trend
toward suppression of the expression of these genes and/or gene signatures upon
treatment with anti-IFNalpha mAb.
CONCLUSION: IFNalpha/beta-inducible gene signatures in whole blood are effective
pharmacodynamic biomarkers to evaluate anti-IFNalpha mAb therapy in SLE.
Anti-IFNalpha mAb can neutralize overexpression of IFNalpha/beta-inducible genes
in whole blood and lesional skin from SLE patients and has profound effects on
signaling pathways that may be downstream of IFNalpha in SLE. Interferon (IFN) signature genes have been shown to be expressed highly in
peripheral blood of patients with systemic lupus erythematosus (SLE), especially
in the presence of active disease. However, the expression of this gene
signature in individuals with incomplete forms of lupus and the pathogenic
relationship between IFN signature genes and autoantibody production have not
been explored fully. In the present study, we examined the gene expression and
autoantibody profiles of patients diagnosed with incomplete lupus erythematosus
(ILE) to determine correlations of the gene expression signature with
autoantibody production. Gene expression analysis was carried out on the 24K
Illumina Human Refseq-8 arrays using blood samples from 84 subjects, including
patients with SLE (n = 27) or ILE (n = 24), first-degree relatives (FDR) of
these patients (n = 22) and non-autoimmune control (NC) individuals (n = 11).
Autoantibody expression was measured using standard immunoassays and autoantigen
proteomic arrays. Up-regulation of a set of 63 IFN signature genes was seen in
83% of SLE patients and 50% of ILE patients. High levels of IFN gene expression
in ILE and SLE showed significant correlations with the expression of a subset
of IgG autoantibodies, including chromatin, dsDNA, dsRNA, U1snRNP, Ro/SSA,
La/SSB, topoisomerase I and Scl 70, while low IFN levels were correlated with
immunoglobulin (Ig)M autoreactivity. These studies suggest that in patients with
ILE the IFN gene expression signature may identify a subset of these individuals
who are at risk for disease progression. Furthermore, high levels of alpha IFN
may promote autoantibody class-switch from IgM to the more pathogenic IgG class. Patients with systemic lupus erythematosus (SLE) have a markedly increased risk
to develop cardiovascular disease, and traditional cardiovascular risk factors
fail to account for this increased risk. We used microarray to probe the
platelet transcriptome in patients with SLE and healthy controls, and the gene
and protein expression of a subset of differentially expressed genes was further
investigated and correlated to platelet activation status. Real-time PCR was
used to confirm a type I interferon (IFN) gene signature in patients with SLE,
and the IFN-regulated proteins PRKRA, IFITM1 and CD69 (P < .0001) were found to
be up-regulated in platelets from SLE patients compared with healthy volunteers.
Notably, patients with a history of vascular disease had increased expression of
type I IFN-regulated proteins as well as more activated platelets compared with
patients without vascular disease. We suggest that interferogenic immune
complexes stimulate production of IFNα that up-regulates the megakaryocytic type
I IFN-regulated genes and proteins. This could affect platelet activation and
contribute to development of vascular disease in SLE. In addition, platelets
with type I IFN signature could be a novel marker for vascular disease in SLE. OBJECTIVE: To characterise activation of the type I interferon (IFN) pathway in
patients with systemic lupus erythematosus (SLE), dermatomyositis (DM),
polymyositis (PM), rheumatoid arthritis (RA) and systemic scleroderma (SSc) and
to evaluate the potential to develop a molecular diagnostic tool from the
peripheral blood that reflects this activation in disease-affected tissues.
METHODS: Overexpressed transcripts were identified in the whole blood (WB) of
262 patients with SLE, 44 with DM, 33 with PM, 28 with SSc and 89 with RA and
compared with 24 healthy subjects using Affymetrix microarrays. A five gene type
I IFN signature was assessed in these subjects to identify subpopulations
showing both activation and concordance of the type I IFN pathway in the
peripheral blood and disease-affected tissues of each disease and to correlate
activation of this pathway in the WB with clinical measurements.
RESULTS: A common set of 36 type I IFN inducible transcripts were identified
among the most overexpressed in the WB of all subjects. Significant activation
of the type I IFN pathway in subgroups of each of the five diseases studied was
observed. Baseline disease activity measurements correlated with a type I IFN
gene signature in the WB of subjects with SLE, PM and SSc, as did various serum
autoantibody levels in subjects with SLE and DM. This signature was also well
correlated between disease-affected tissue and WB in subjects with SLE, DM, PM
and SSc.
CONCLUSIONS: The results indicate that the type I IFN pathway is activated in
patient subsets of five rheumatic diseases and suggest that these subsets may
benefit from anti-IFN therapy. BACKGROUND: There is increased expression of type I interferon (IFN)-regulated
proteins in the blood and target tissues of patients with cutaneous lupus
erythematosus (CLE) and systemic lupus erythematosus (SLE). Patients with SLE
have increased IFN-regulated gene expression pointing towards a possible
underlying genetic defect.
OBJECTIVES: To determine expression levels of five type I IFN-regulated genes
that are highly expressed in SLE in the peripheral blood of patients with CLE
and to correlate the expression levels with cutaneous disease activity.
METHODS: Peripheral blood was obtained from 10 healthy controls and 30 patients
with CLE, including eight with concomitant SLE. Total RNA was extracted and
reverse transcribed into complementary DNA. Gene expression levels were measured
by real-time polymerase chain reaction. Gene expression was normalized to GAPDH,
standardized to healthy controls and then summed to calculate an IFN score for
each patient. Disease activity was assessed with the Cutaneous Lupus Area and
Severity Index (CLASI).
RESULTS: Patients with subacute CLE (SCLE) and discoid lupus erythematosus (DLE)
had elevated IFN scores compared with healthy controls regardless of concomitant
SLE (P < 0·01 with SLE and P < 0·05 without SLE). There was no difference
between patients with tumid lupus erythematosus (TLE) and healthy controls. The
IFN score correlated with CLASI scores (Spearman's rho = 0·55, P = 0·0017).
CONCLUSIONS: Patients with SCLE and DLE have an IFN signature, as seen in SLE.
The level of gene expression correlates with cutaneous disease activity. These
findings support a shared pathogenesis between SLE and some subtypes of CLE. Systemic lupus erythematosus (SLE) is a generalized autoimmune disease
characterized by abnormal B cell activation and the occurrence of increased
frequencies of circulating plasma cells (PC). The molecular characteristics and
nature of circulating PC and B cells in SLE have not been completely
characterized. Microarray analysis of gene expression was used to characterize
circulating PC in subjects with active SLE. Flow cytometry was used to sort PC
and comparator B cell populations from active SLE blood, normal blood and normal
tonsil. The gene expression profiles of the sorted B cell populations were then
compared. SLE PC exhibited a similar gene expression signature as tonsil PC. The
differences in gene expression between SLE PC and normal tonsil PC and tonsil
plasmablasts (PB) suggest a mature Ig secreting cell phenotype in the former
population. Despite this, SLE PC differed in expression of about half the genes
from previously published gene expression profiles of normal bone marrow PC,
indicating that these cells had not achieved a fully mature status. Abnormal
expression of several genes, including CXCR4 and S1P(1), suggests a mechanism
for the persistence of SLE PC in the circulation. All SLE B cell populations
revealed an interferon (IFN) gene signature previously only reported in
unseparated SLE peripheral blood mononuclear cells. These data indicate that SLE
PC are a unique population of Ig secreting cells with a gene expression profile
indicative of a mature, but not fully differentiated phenotype. In recent years, biomarkers have shown significant promise in helping
decision-making in drug development. Systemic lupus erythematosus (SLE) is a
complicated and highly heterogeneous disease that involves all organs. Only one
drug, belimumab, has been approved by the US Food and Drug Administration to
treat SLE during the last 50 years and there remains a high unmet medical need
to develop new and effective therapies to benefit different patient populations
in SLE. Due to the extreme heterogeneity of the disease and the complex and
rigorous process to validate individual biomarkers, there is currently a very
limited number of consensus biomarkers to aid the treatment decision-making in
SLE. This review provides a snapshot of some biomarkers in the field that have
the potential to make a big impact on drug development and/or treatment
decisions by physicians. These include: type I interferon (IFN) gene signature
as a pharmacodynamic marker and potential predictive marker for anti-type I IFN
therapy; anti-double stranded DNA as a disease marker and potential predictive
marker for flares; the complements and neutrophil signatures as disease marker
of SLE; and TWEAK (a tumor necrosis factor family member produced by
macrophages) and MCP-1 as potential markers to predict renal flares. Most of
these markers need carefully planned and prospective studies with high
statistical power to confirm their respective utilities. With the development
and application of powerful new technologies, more successful biomarkers will
emerge in SLE. This could improve the management of patients in the clinic and
facilitate the development of novel and more effective therapeutics for this
difficult-to-treat disease. OBJECTIVE: To evaluate the safety and tolerability of multiple intravenous (IV)
doses of sifalimumab in adults with moderate-to-severe systemic lupus
erythematosus (SLE).
METHODS: In this multicenter, double-blind, placebo-controlled, sequential
dose-escalation study, patients were randomized 3:1 to receive IV sifalimumab
(0.3, 1.0, 3.0, or 10.0 mg/kg) or placebo every 2 weeks to week 26, then
followed up for 24 weeks. Safety assessment included recording of
treatment-emergent adverse events (AEs) and serious AEs. Pharmacokinetics,
immunogenicity, and pharmacodynamics were evaluated, and disease activity was
assessed.
RESULTS: Of 161 patients, 121 received sifalimumab (26 received 0.3 mg/kg; 25,
1.0 mg/kg; 27, 3.0 mg/kg; and 43, 10 mg/kg) and 40 received placebo. Patients
were predomitly female (95.7%). At baseline, patients had moderate-to-severe
disease activity (mean SLE Disease Activity Index score 11.0), and most (75.2%)
had a high type I interferon (IFN) gene signature. In the sifalimumab group
versus the placebo group, the incidence of ≥1 treatment-emergent AE was 92.6%
versus 95.0%, ≥1 serious AE was 22.3% versus 27.5%, and ≥1 infection was 67.8%
versus 62.5%; discontinuations due to AEs occurred in 9.1% versus 7.5%, and
death occurred in 3.3% (n=4) versus 2.5% (n=1). Serum sifalimumab concentrations
increased in a linear and dose-proportional manner. Inhibition of the type I IFN
gene signature was sustained during treatment in patients with a high baseline
signature. No statistically significant differences in clinical activity (SLEDAI
and British Isles Lupus Assessment Group score) between sifalimumab and placebo
were observed. However, when adjusted for excess burst steroids, SLEDAI change
from baseline showed a positive trend over time. A trend toward normal
complement C3 or C4 level at week 26 was seen in the sifalimumab groups compared
with baseline.
CONCLUSION: The observed safety/tolerability and clinical activity profile of
sifalimumab support its continued clinical development for SLE. BACKGROUND AND OBJECTIVES: Sifalimumab is a fully human immunoglobulin G1κ
monoclonal antibody that binds to and neutralizes a majority of the subtypes of
human interferon-α. Sifalimumab is being evaluated as a treatment for systemic
lupus erythematosus (SLE). The primary objectives of this analysis were (a) to
develop a population pharmacokinetic model for sifalimumab in SLE; (b) to
identify and quantitate the impact of patient/disease characteristics on
pharmacokinetic variability; and (c) to evaluate fixed versus body weight
(WT)-based dosing regimens.
METHODS: Sifalimumab serum concentration-time data were collected from a phase
Ib study (MI-CP152) designed to evaluate the safety and tolerability of
sifalimumab in adult patients with SLE. Sifalimumab was administered every 14
days as a 30- to 60-minute intravenous infusion with escalating doses of 0.3,
1.0, 3.0, and 10 mg/kg and serum concentrations were collected over 350 days. A
total of 120 patients provided evaluable pharmacokinetic data with a total of
2,370 serum concentrations. Sifalimumab serum concentrations were determined
using a validated colorimetric enzyme-linked immunosorbent assay (ELISA) with a
lower limit of quantitation of 1.25 μg/mL. Population pharmacokinetic modeling
of sifalimumab was performed using a non-linear mixed effects modeling approach
with NONMEM VII software. Impact of patient demographics, clinical indices, and
biomarkers on pharmacokinetic parameters were explored using a stepwise forward
selection and backward elimination approach. The appropriateness of the final
model was tested using visual predictive check (VPC). The impact of body
WT-based and fixed dosing of sifalimumab was evaluated using a simulation
approach. The final population model was utilized for phase IIb dosing
projections.
RESULTS: Sifalimumab pharmacokinetics were best described using a
two-compartment linear model with first order elimination. Following intravenous
dosing, the typical clearance (CL) and central volume of distribution (V 1) were
estimated to be 176 mL/day and 2.9 L, respectively. The estimates (coefficient
of variation) of between-subject variability for CL and V 1 were 28 and 31 %,
respectively. Patient baseline body WT, interferon gene signature from 21 genes,
steroid use, and sifalimumab dose were identified as significant covariates for
CL, whereas only baseline body WT was a significant covariate for V 1 and
peripheral volume of distribution (V 2). Although the above-mentioned covariates
were statistically significant, they did not explain variability in
pharmacokinetic parameters to any relevant extent (<7 %). Thus, no dosing
adjustments are necessary. VPC confirmed good predictability of the final
population pharmacokinetic model. Simulation results demonstrate that both fixed
and body WT-based dosing regimens yield similar median steady state
concentrations and overall variability. Fixed sifalimumab doses of 200, 600, and
1,200 mg monthly (with a loading dose at Day 14) were selected for a phase IIb
clinical trial.
CONCLUSION: A two-compartment population pharmacokinetic model adequately
described sifalimumab pharmacokinetics. The estimated typical pharmacokinetic
parameters were similar to other monoclonal antibodies without target mediated
elimination. Although the population pharmacokinetic analysis identified some
statistically significant covariates, they explained <7 % between-subject
variability in pharmacokinetic parameters indicating that these covariates are
not clinically relevant. The population pharmacokinetic analysis also
demonstrated the feasibility of switching to fixed doses in phase IIb clinical
trials of sifalimumab. INTRODUCTION: A hallmark of systemic autoimmune diseases like systemic lupus
erythematosus (SLE) is the increased expression of interferon (IFN) type I
inducible genes, so-called IFN type I signature. Recently, T-helper 17 subset
(Th17 cells), which produces IL-17A, IL-17F, IL-21, and IL-22, has been
implicated in SLE. As CCR6 enriches for Th17 cells, we used this approach to
investigate whether CCR6⁺ memory T-helper cells producing IL-17A, IL-17F, IL-21,
and/or IL-22 are increased in SLE patients and whether this increase is related
to the presence of IFN type I signature.
METHODS: In total, 25 SLE patients and 15 healthy controls (HCs) were included.
SLE patients were divided into IFN type I signature-positive (IFN⁺) (n = 16) and
negative (IFN⁻) (n = 9) patients, as assessed by mRNA expression of
IFN-inducible genes (IFIGs) in monocytes. Expression of IL-17A, IL-17F, IL-21,
and IL-22 by CD4⁺CD45RO⁺CCR6⁺ T cells (CCR6⁺ cells) was measured with flow
cytometry and compared between IFN⁺, IFN⁻ patients and HCs.
RESULTS: Increased percentages of IL-17A and IL-17A/IL-17F double-producing
CCR6⁺ cells were observed in IFN⁺ patients compared with IFN⁻ patients and HCs.
IL-17A and IL-17F expression within CCR6⁺ cells correlated significantly with
IFIG expression. In addition, we found significant correlation between B-cell
activating factor of the tumor necrosis family (BAFF)-a factor strongly
correlating with IFN type I - and IL-21 producing CCR6⁺ cells.
CONCLUSIONS: We show for the first time higher percentages of IL-17A and
IL-17A/IL-17F double-producing CCR6⁺ memory T-helper cells in IFN⁺ SLE patients,
supporting the hypothesis that IFN type I co-acts with Th17 cytokines in SLE
pathogenesis. Type I interferons (IFN) are primarily regarded as an inhibitor of viral
replication. However, type I IFN, mainly IFNalpha, plays a major role in
activation of both the innate and adaptive immune systems. Systemic lupus
erythematosus (SLE) is a chronic, multi-systemic, inflammatory autoimmune
disease with undefined etiology. SLE is characterized by dysregulation of both
the innate and the adaptive immune systems. An increased expression of type I
IFN-regulated genes, termed IFN signature, has been reported in patients with
SLE. We review here the role of IFNalpha in the pathogenesis and course of SLE
and the possible role of IFNalpha inhibition as a novel treatment for lupus
patients. Blood gene expression profiling has led to major advances in the field of
rheumatology over the last few decades. Specifically, DNA microarray technology
has been integral in increasing our knowledge of key players in the pathogenesis
of some rare pediatric rheumatic diseases. Our group, using microarray analysis,
identified the interferon (IFN) gene signature in pediatric systemic lupus
erythematosus (SLE) and has published data that suggest high doses of
intravenous corticosteroid treatment may have benefit over strictly oral
regimens. Additionally, DNA microarray technology led to our discovery that the
interleukin (IL)-1 gene signature is associated with systemic juvenile
idiopathic arthritis (sJIA) and to the use of IL-1 blockade with anakinra in
this disease. We also reported the biologic rationale for use of anakinra early
in the disease course. Anakinra is now being used as first-line treatment in
sJIA in multiple centers. Herein, we review how information obtained from blood
gene expression profiling has changed our clinical practice. OBJECTIVES: The interferon (IFN) signature (IS) in patients with systemic lupus
erythematosus (SLE) includes over 100 genes induced by type I IFN pathway
activation. We developed a method to quantify the IS using three genes-the IS
metric (ISM)-and characterised the clinical characteristics of patients with SLE
with different ISM status from multiple clinical trials.
METHODS: Blood microarray expression data from a training cohort of patients
with SLE confirmed the presence of the IS and identified surrogate genes. We
assayed these genes in a quantitative PCR (qPCR) assay, yielding an ISM from the
IS. The association of ISM status with clinical disease characteristics was
assessed in patients with extrarenal lupus and lupus nephritis from four
clinical trials.
RESULTS: Three genes, HERC5, EPSTI and CMPK2, correlated well with the IS
(p>0.96), and composed the ISM qPCR assay. Using the 95th centile for healthy
control data, patients with SLE from different studies were classified into two
ISM subsets-ISM-Low and ISM-High-that are longitudinally stable over 36 weeks.
Significant associations were identified between ISM-High status and higher
titres of anti-dsDNA antibodies, presence of anti extractable nuclear antigen
autoantibodies, elevated serum B cell activating factor of the tumour necrosis
factor family (BAFF) levels, and hypocomplementaemia. However, measures of
overall clinical disease activity were similar for ISM-High and ISM-Low groups.
CONCLUSIONS: The ISM is an IS biomarker that divides patients with SLE into two
subpopulations-ISM-High and ISM-Low-with differing serological manifestations.
The ISM does not distinguish between high and low disease activity, but may have
utility in identifying patients more likely to respond to treatment(s) targeting
IFN-α.
CLINICALTRIALSGOV REGISTRATION NUMBER: NCT00962832. OBJECTIVES: The efficacy and safety of sifalimumab were assessed in a phase IIb,
randomised, double-blind, placebo-controlled study (NCT01283139) of adults with
moderate to severe active systemic lupus erythematosus (SLE).
METHODS: 431 patients were randomised and received monthly intravenous
sifalimumab (200 mg, 600 mg or 1200 mg) or placebo in addition to
standard-of-care medications. Patients were stratified by disease activity,
interferon gene-signature test (high vs low based on the expression of four
genes) and geographical region. The primary efficacy end point was the
percentage of patients achieving an SLE responder index response at week 52.
RESULTS: Compared with placebo, a greater percentage of patients who received
sifalimumab (all dosages) met the primary end point (placebo: 45.4%; 200 mg:
58.3%; 600 mg: 56.5%; 1200 mg 59.8%). Other improvements were seen in Cutaneous
Lupus Erythematosus Disease Area and Severity Index score (200 mg and 1200 mg
monthly), Physician's Global Assessment (600 mg and 1200 mg monthly), British
Isles Lupus Assessment Group-based Composite Lupus Assessment (1200 mg monthly),
4-point reductions in the SLE Disease Activity Index-2000 score and reductions
in counts of swollen joints and tender joints. Serious adverse events occurred
in 17.6% of patients on placebo and 18.3% of patients on sifalimumab. Herpes
zoster infections were more frequent with sifalimumab treatment.
CONCLUSIONS: Sifalimumab is a promising treatment for adults with SLE.
Improvement was consistent across various clinical end points, including global
and organ-specific measures of disease activity.
TRIAL REGISTRATION NUMBER: NCT01283139; Results. OBJECTIVE: To characterize baseline gene expression and pharmacodynamically
induced changes in whole blood gene expression in 1,760 systemic lupus
erythematosus (SLE) patients from 2 phase III, 52-week, randomized,
placebo-controlled, double-blind studies in which patients were treated with the
BAFF-blocking IgG4 monoclonal antibody tabalumab.
METHODS: Patient samples were obtained from SLE patients from the ILLUMINATE-1
and ILLUMINATE-2 studies, and control samples were obtained from healthy donors.
Blood was collected in Tempus tubes at baseline, week 16, and week 52. RNA was
analyzed using Affymetrix Human Transcriptome Array 2.0 and NanoString.
RESULTS: At baseline, expression of the interferon (IFN) response gene was
elevated in patients compared with controls, with 75% of patients being positive
for this IFN response gene signature. There was, however, substantial
heterogeneity of IFN response gene expression and complex relationships among
gene networks. The IFN response gene signature was a predictor of time to
disease flare, independent of anti-double-stranded DNA (anti-dsDNA) antibody and
C3 and C4 levels, and overall disease activity. Pharmacodynamically induced
changes in gene expression following tabalumab treatment were extensive,
occurring predomitly in B cell-related and immunoglobulin genes, and were
consistent with other pharmacodynamic changes including anti-dsDNA antibody, C3,
and immunoglobulin levels.
CONCLUSION: SLE patients demonstrated increased expression of an IFN response
gene signature (75% of patients had an elevated IFN response gene signature) at
baseline in ILLUMINATE-1 and ILLUMINATE-2. Substantial heterogeneity of gene
expression was detected among individual patients and in gene networks. The IFN
response gene signature was an independent risk factor for future disease
flares. Pharmacodynamic changes in gene expression were consistent with the
mechanism of BAFF blockade by tabalumab. OBJECTIVE: To assess the efficacy and safety of anifrolumab, a type I interferon
(IFN) receptor antagonist, in a phase IIb, randomized, double-blind,
placebo-controlled study of adults with moderate-to-severe systemic lupus
erythematosus (SLE).
METHODS: Patients (n = 305) were randomized to receive intravenous anifrolumab
(300 mg or 1,000 mg) or placebo, in addition to standard therapy, every 4 weeks
for 48 weeks. Randomization was stratified by SLE Disease Activity Index 2000
score (<10 or ≥10), oral corticosteroid dosage (<10 or ≥10 mg/day), and type I
IFN gene signature test status (high or low) based on a 4-gene expression assay.
The primary end point was the percentage of patients achieving an SLE Responder
Index (SRI[4]) response at week 24 with sustained reduction of oral
corticosteroids (<10 mg/day and less than or equal to the dose at week 1 from
week 12 through 24). Other end points (including SRI[4], British Isles Lupus
Assessment Group [BILAG]-based Composite Lupus Assessment [BICLA], modified
SRI[6], and major clinical response) were assessed at week 52. The primary end
point was analyzed in the modified intent-to-treat (ITT) population and type I
IFN-high subpopulation. The study result was considered positive if the primary
end point was met in either of the 2 study populations. The Type I error rate
was controlled at 0.10 (2-sided), within each of the 2 study populations for the
primary end point analysis.
RESULTS: The primary end point was met by more patients treated with anifrolumab
(34.3% of 99 for 300 mg and 28.8% of 104 for 1,000 mg) than placebo (17.6% of
102) (P = 0.014 for 300 mg and P = 0.063 for 1,000 mg, versus placebo), with
greater effect size in patients with a high IFN signature at baseline (13.2% in
placebo-treated patients versus 36.0% [P = 0.004] and 28.2% [P = 0.029]) in
patients treated with anifrolumab 300 mg and 1,000 mg, respectively. At week 52,
patients treated with anifrolumab achieved greater responses in SRI(4) (40.2%
versus 62.6% [P < 0.001] and 53.8% [P = 0.043] with placebo, anifrolumab 300 mg,
and anifrolumab 1,000 mg, respectively), BICLA (25.7% versus 53.5% [P < 0.001]
and 41.2% [P = 0.018], respectively), modified SRI(6) (28.4% versus 49.5%
[P = 0.002] and 44.7% [P = 0.015], respectively), major clinical response (BILAG
2004 C or better in all organ domains from week 24 through week 52) (6.9% versus
19.2% [P = 0.012] and 17.3% [P = 0.025], respectively), and several other global
and organ-specific end points. Herpes zoster was more frequent in the
anifrolumab-treated patients (2.0% with placebo treatment versus 5.1% and 9.5%
with anifrolumab 300 mg and 1,000 mg, respectively), as were cases reported as
influenza (2.0% versus 6.1% and 7.6%, respectively), in the anifrolumab
treatment groups. Incidence of serious adverse events was similar between groups
(18.8% versus 16.2% and 17.1%, respectively).
CONCLUSION: Anifrolumab substantially reduced disease activity compared with
placebo across multiple clinical end points in the patients with
moderate-to-severe SLE. OBJECTIVE: We investigated the mechanistic and pharmacological properties of
anifrolumab, a fully human, effector-null, anti-type I interferon (IFN) alpha
receptor 1 (IFNAR1) monoclonal antibody in development for SLE.
METHODS: IFNAR1 surface expression and internalisation on human monocytes before
and after exposure to anifrolumab were assessed using confocal microscopy and
flow cytometry. The effects of anifrolumab on type I IFN pathway activation were
assessed using signal transducer and activator of transcription 1 (STAT1)
phosphorylation, IFN-stimulated response element-luciferase reporter cell assays
and type I IFN gene signature induction. The ability of anifrolumab to inhibit
plasmacytoid dendritic cell (pDC) function and plasma cell differentiation was
assessed by flow cytometry and ELISA. Effector-null properties of anifrolumab
were assessed in antibody-dependent cell-mediated cytotoxicity (ADCC) and
complement-dependent cytotoxicity (CDC) assays with B cells.
RESULTS: Anifrolumab reduced cell surface IFNAR1 by eliciting IFNAR1
internalisation. Anifrolumab blocked type I IFN-dependent STAT1 phosphorylation
and IFN-dependent signalling induced by recombit and pDC-derived type I IFNs
and serum of patients with SLE. Anifrolumab suppressed type I IFN production by
blocking the type I IFN autoamplification loop and inhibited proinflammatory
cytokine induction and the upregulation of costimulatory molecules on stimulated
pDCs. Blockade of IFNAR1 suppressed plasma cell differentiation in pDC/B cell
co-cultures. Anifrolumab did not exhibit CDC or ADCC activity.
CONCLUSIONS: Anifrolumab potently inhibits type I IFN-dependent signalling,
including the type I IFN autoamplification loop, and is a promising therapeutic
for patients with SLE and other diseases that exhibit chronic dysfunctional type
I IFN signalling. OBJECTIVE: The interferon (IFN) signature is related to disease activity and
vascular disease in systemic lupus erythematosus (SLE) and antiphospholipid
syndrome (APS) and represents a promising therapeutic target. Quantification of
the IFN signature is currently performed by gene expression analysis, limiting
its current applicability in clinical practice. Therefore, the objective of this
study was to establish an easy to measure biomarker for the IFN signature.
METHODS: Serum levels of galectin-9, CXCL-10 (IP-10) and tumour necrosis factor
receptor type II (TNF-RII) were measured in patients with SLE, SLE+APS and
primary APS (PAPS) and healthy controls (n=148) after an initial screening of
serum analytes in a smaller cohort (n=43). Analytes were correlated to measures
of disease activity and the IFN signature. The performance of galectin-9,
CXCL-10 and TNF-RII as biomarkers to detect the IFN signature was assessed by
receiver operating characteristic curves.
RESULTS: Galectin-9, CXCL-10 and TNF-RII were elevated in patients with SLE,
SLE+APS and PAPS (p<0.05) and correlated with disease activity and tissue factor
expression. Galectin-9 correlated stronger than CXCL-10 or TNF-RII with the IFN
score (r=0.70, p<0.001) and was superior to CXCL-10 or TNF-RII in detecting the
IFN signature (area under the curve (AUC) 0.86). Importantly, in patients with
SLE(±APS), galectin-9 was also superior to anti-dsDNA antibody (AUC 0.70), or
complement C3 (AUC 0.70) and C4 (AUC 0.78) levels in detecting the IFN
signature.
CONCLUSION: Galectin-9 is a novel, easy to measure hence clinically applicable
biomarker to detect the IFN signature in patients with systemic autoimmune
diseases such as SLE and APS. Systemic lupus erythematosus (SLE) is a complex autoimmune disease in which 70%
of patients experience disfiguring skin inflammation (grouped under the rubric
of cutaneous lupus erythematosus [CLE]). There are limited treatment options for
SLE and no Food and Drug Administration-approved therapies for CLE. Studies have
revealed that IFNs are important mediators for SLE and CLE, but the mechanisms
by which IFNs lead to disease are still poorly understood. We aimed to
investigate how IFN responses in SLE keratinocytes contribute to development of
CLE. A cohort of 72 RNA sequencing samples from 14 individuals (seven SLE and
seven healthy controls) were analyzed to study the transcriptomic effects of
type I and type II IFNs on SLE versus control keratinocytes. In-depth analysis
of the IFN responses was conducted. Bioinformatics and functional assays were
conducted to provide implications for the change of IFN response. A significant
hypersensitive response to IFNs was identified in lupus keratinocytes, including
genes (IFIH1, STAT1, and IRF7) encompassed in SLE susceptibility loci. Binding
sites for the transcription factor PITX1 were enriched in genes that exhibit
IFN-sensitive responses. PITX1 expression was increased in CLE lesions based on
immunohistochemistry, and by using small interfering RNA knockdown, we
illustrated that PITX1 was required for upregulation of IFN-regulated genes in
vitro. SLE patients exhibit increased IFN signatures in their skin secondary to
increased production and a robust, skewed IFN response that is regulated by
PITX1. Targeting these exaggerated pathways may prove to be beneficial to
prevent and treat hyperinflammatory responses in SLE skin. Systemic lupus erythematosus (SLE) is a complex autoimmune disease which affects
multiple organs. The type I interferon (IFN) gene signature and circulating
autoantibodies are hallmarks of SLE. Plasmacytoid dendritic cells (pDCs) are
considered the main producers of type I IFN and production is modulated by
multiple other immune cell types. In SLE, essentially every immune cell type is
dysregulated and aberrant deregulation is thought to be due, in part, to direct
or indirect exposure to IFN. Genetic variants within or around the transcription
factor interferon regulatory factor 5 (IRF5) associate with SLE risk. Elevated
IFNα activity was detected in the sera of SLE patients carrying IRF5 risk
polymorphisms who were positive for either anti-RNA binding protein (anti-RBP)
or anti-double-stranded DNA (anti-dsDNA) autoantibodies. Neutrophils are also an
important source of type I IFNs and are found in abundance in human blood.
Neutrophil extracellular traps (NETs) are considered a potential source of
antigenic trigger in SLE that can lead to type I IFN gene induction, as well as
increased autoantibody production. In this review, we will focus on immune cell
types that produce type I IFNs and/or are affected by type I IFN in SLE. In
addition, we will discuss potential inducers of endogenous type I IFN production
in SLE. Last, we will postulate how the different immune cell populations may be
affected by an IRF5-SLE risk haplotype. OBJECTIVES: Type I interferon (IFN) is implicated in systemic lupus
erythematosus (SLE) pathogenesis. We aimed to identify type I IFN
signaling-dependent and -independent molecular pathways in a large population of
patients with SLE.
METHODS: Baseline blood samples from adult patients with moderate to severe SLE
from two Phase IIb studies (NCT01438489, n = 265; NCT01283139, n = 416) were
profiled using whole transcriptome array analyses. Type I IFN gene signature
(IFNGS) test status (high or low) was determined using a validated qualitative
polymerase chain reaction-based test. IFN-type-specific signatures were
developed by stimulating healthy blood with IFN-β, IFN-γ, IFN-λ, IFN-ω, or
pooled IFN-α. These, and multiple literature-derived cell type and cytokine
pathway signatures, were evaluated in individual and pooled study populations. A
Fisher's exact test was used for associations, adjusted for false discovery
rate.
RESULTS: Whole blood samples from IFNGS test-high patients were enriched versus
IFNGS test-low patients for CD40L signaling (Q < 0.001), CXC cytokine
(Q < 0.001), TLR8-mediated monocyte activation (Q < 0.001), IgG (Q < 0.001),
major histocompatibility complex class I (Q < 0.001), and plasma cell
(Q < 0.001) gene expression signatures. IFNGS test-low patients had significant
enrichment of eosinophil (Q < 0.001), IFN-γ-specific (Q = 0.005), and T-cell or
B-cell (Q < 0.001) signatures. Similar enrichment profiles were demonstrated in
patients with primary Sjögren's syndrome, systemic sclerosis, and
dermatomyositis.
CONCLUSIONS: IFNGS test-high patients overexpressed many gene signatures
associated with SLE pathogenesis compared with IFNGS test-low patients,
reflecting broad immune activation. These results provide new insights into the
molecular heterogeneity underlying SLE pathogenesis, highlighting shared
mechanisms beyond type I IFN, across several autoimmune diseases.
TRIAL REGISTRATION: Clinicaltrials.gov: NCT01438489 and NCT01283139. OBJECTIVES: Plasmacytoid dendritic cells (pDCs), through the production of type
1 interferons (IFNs) and other cytokines, are major contributors to systemic
lupus erythematosus (SLE) pathogenesis. IL-3 promotes pDC survival, but its role
in SLE is not well characterised. This study investigated serum IL-3 and IFN
levels, and a whole blood 'IL-3 gene signature', in human SLE.
METHODS: Serum cytokine levels were measured by ELISA in n = 42 SLE patients,
and n = 44 healthy donors. IL-3-regulated genes were determined by RNASeq of
healthy donor whole blood cells (WBCs) stimulated in vitro with IL-3 for 6 or
24 h. Whole blood cell RNASeq analysis was undertaken in a separate cohort of
n = 31 SLE patients, and n = 28 healthy donors.
RESULTS: Serum IL-3 levels correlated with IFNα (r = 0.612, 95% CI 0.455-0.733,
P < 0.001) and type III IFN (r = 0.585, 95% CI 0.406-0.720, P < 0.0001). IL-3
stimulation of WBC in vitro altered 794 genes (-1 ≥ logFC ≥ 1, FDR < 0.05), of
which 35 overlapped with genes differentially expressed between SLE and healthy
donors. These 35 genes were expressed in 27/31 SLE donors, revealing the
presence of an 'IL-3 gene signature'. There was strong correlation between the
IL-3 signature and an IFN signature, as determined by hierarchical clustering of
the 500 most variable genes in SLE donors (r = 0.939, 95% CI 0.898-0.964,
P < 0.0001).
CONCLUSION: A dual IL-3/IFN gene signature is a feature of SLE. An association
between IL-3 and IFN raises the possibility that dual blockade of IL-3 and IFN
may be especially useful for SLE patients with this dual cytokine gene
signature. BACKGROUND: Systemic lupus erythematosus (SLE) is a complex multi-system
disease, characterized by both autoimmune and autoinflammatory clinical and
laboratory features. The role of type I interferon (IFN) in SLE has been
demonstrated from the 2000s, by gene expression analyses showing significant
over-expression of genes related to type I IFN signalling pathway (IFN
signature). However, several studies questioned the role of measuring the
intensity of IFN signature (IFN score) to chase SLE activity. We would assess if
the IFN signature can help the clinical and therapeutic stratification of
patients with pediatric SLE.
METHODS: We measured the IFN score in peripheral whole blood from a series of
subjects with childhood-onset SLE and correlated the results with clinical and
laboratory parameters.
RESULTS: Thirty-one subjects were included in the study, among which the 87%
displayed a positive IFN score. The only significant relation was found for high
IFN score in subjects with normocomplementemia. No correlation was observed
between IFN score and SLEDAI-2K, BILAG-2004 and SLICC. Patients with high IFN
score and normal complement levels also presented lower anti-dsDNA antibodies.
CONCLUSIONS: The integration between IFN signature analysis and complement
levels may easily distinguish two groups of subjects, in which the autoimmune or
autoinflammatory component of the disease seems to be prevalent. |
Has FTY720 been considered for the treatment of stroke? | Yes, FTY720 is a strong candidate for stroke treatment. | FTY720 (Fingolimod) is a known sphingosine-1-phosphate (S1P) receptor agonist
that exerts strong anti-inflammatory effects and was approved as the first oral
drug for the treatment of multiple sclerosis by the US Food and Drug
Administration (FDA) in 2010. FTY720 is mainly associated with unique functional
"antagonist" and "agonist" mechanisms. The functional antagonistic mechanism is
mediated by the transient down-regulation and degradation of S1P receptors on
lymphocytes, which prevents lymphocytes from entering the blood stream from the
lymph node. This subsequently results in the development of lymphopenia and
reduces lymphocytic inflammation. Functional agonistic mechanisms are executed
through S1P receptors expressed on the surface of various cells including
neurons, astrocytes, microglia, and blood vessel endothelial cells. These
functions might play important roles in regulating anti-apoptotic systems,
modulating brain immune and phagocytic activities, preserving the
Blood-Brain-Barrier (BBB), and the proliferation of neural precursor cells.
Recently, FTY720 have shown receptor-independent effects, including
intracellular target bindings and epigenetic modulations. Many researchers have
recognized the positive effects of FTY720 and launched basic and clinical
experiments to test the use of this agent against stroke. Although the mechanism
of FTY720 has not been fully elucidated, its efficacy against cerebral stroke is
becoming clear, not only in animal models, but also in ischemic stroke patients
through clinical trials. In this article, we review the data obtained from
laboratory findings and preliminary clinical trials using FTY720 for stroke
treatment. |
List R packages for lipidomics | R packages for lipidomics: lipidomics, masspix, lipidms, lipidr and lipid mini-on. | INTRODUCTION: Mass spectrometry imaging (MSI) experiments result in complex
multi-dimensional datasets, which require specialist data analysis tools.
OBJECTIVES: We have developed massPix-an R package for analysing and
interpreting data from MSI of lipids in tissue.
METHODS: massPix produces single ion images, performs multivariate statistics
and provides putative lipid annotations based on accurate mass matching against
generated lipid libraries.
RESULTS: Classification of tissue regions with high spectral similarly can be
carried out by principal components analysis (PCA) or k-means clustering.
CONCLUSION: massPix is an open-source tool for the analysis and statistical
interpretation of MSI data, and is particularly useful for lipidomics
applications. High resolution LC-MS untargeted lipidomics using data independent acquisition
(DIA) has the potential to increase lipidome coverage, as it enables the
continuous and unbiased acquisition of all eluting ions. However, the loss of
the link between the precursor and the product ions combined with the high
dimensionality of DIA data sets hinder accurate feature annotation. Here, we
present LipidMS, an R package aimed to confidently identify lipid species in
untargeted LC-DIA-MS. To this end, LipidMS combines a coelution score, which
links precursor and fragment ions with fragmentation and intensity rules.
Depending on the MS evidence reached by the identification function survey,
LipidMS provides three levels of structural annotations: (i) "subclass level",
e.g., PG(34:1); (ii) "fatty acyl level", e.g., PG(16:0_18:1); and (iii) "fatty
acyl position level", e.g., PG(16:0/18:1). The comparison of LipidMS with freely
available data dependent acquisition (DDA) and DIA identification tools showed
that LipidMS provides significantly more accurate and structural informative
lipid identifications. Finally, to exemplify the utility of LipidMS, we
investigated the lipidomic serum profile of patients diagnosed with nonalcoholic
steatohepatitis (NASH), which is the progressive form of nonalcoholic fatty
liver disease, a disorder underlying a strong lipid dysregulation. As previously
published, a significant decrease in lysophosphatidylcholines,
phosphatidylcholines and cholesterol esters and an increase in
phosphatidylethanolamines were observed in NASH patients. Remarkably, LipidMS
allowed the identification of a new set of lipids that may be used for NASH
diagnosis. Altogether, LipidMS has been validated as a tool to assist lipid
identification in the LC-DIA-MS untargeted analysis of complex biological
samples. SUMMARY: Here we introduce Lipid Mini-On, an open-source tool that performs
lipid enrichment analyses and visualizations of lipidomics data. Lipid Mini-On
uses a text-mining process to bin individual lipid names into multiple lipid
ontology groups based on the classification (e.g. LipidMaps) and other
characteristics, such as chain length. Lipid Mini-On provides users with the
capability to conduct enrichment analysis of the lipid ontology terms using a
Shiny app with options of five statistical approaches. Lipid classes can be
added to customize the user's database and remain updated as new lipid classes
are discovered. Visualization of results is available for all classification
options (e.g. lipid subclass and individual fatty acid chains). Results are also
visualized through an editable network of relationships between the individual
lipids and their associated lipid ontology terms. The utility of the tool is
demonstrated using biological (e.g. human lung endothelial cells) and
environmental (e.g. peat soil) samples.
AVAILABILITY AND IMPLEMENTATION: Rodin (R package:
https://github.com/PNNL-Comp-Mass-Spec/Rodin), Lipid Mini-On Shiny app
(https://github.com/PNNL-Comp-Mass-Spec/LipidMiniOn) and Lipid Mini-On online
tool (https://omicstools.pnnl.gov/shiny/lipid-mini-on/).
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. The rapid evolution of mass spectrometry (MS)-based lipidomics has enabled the
simultaneous measurement of numerous lipid classes. With lipidomics datasets
becoming increasingly available, lipidomic-focused software tools are required
to facilitate data analysis as well as mining of public datasets, integrating
lipidomics-unique molecular information such as lipid class, chain length, and
unsaturation. To address this need, we developed lipidr, an open-source
R/Bioconductor package for data mining and analysis of lipidomics datasets.
lipidr implements a comprehensive lipidomic-focused analysis workflow for
targeted and untargeted lipidomics. lipidr imports numerical matrices, Skyline
exports, and Metabolomics Workbench files directly into R, automatically
inferring lipid class and chain information from lipid names. Through
integration with the Metabolomics Workbench API, users can search, download, and
reanalyze public lipidomics datasets seamlessly. lipidr allows thorough data
inspection, normalization, and uni- and multivariate analyses, displaying
results as interactive visualizations. To enable interpretation of lipid class,
chain length, and total unsaturation data, we also developed and implemented a
novel lipid set enrichment analysis. A companion online guide with two live
example datasets is presented at https://www.lipidr.org/. We expect that the
ease of use and innovative features of lipidr will allow the lipidomics research
community to gain novel detailed insights from lipidomics data. |
Which disease can be treated with Relugolix. | Relugolix has a role in treatment of prostate cancer, uterine fibroids, endometriosis and uterine myomas. | OBJECTIVE: To investigate the noninferiority of relugolix compared with
leuprorelin acetate in reducing heavy menstrual bleeding associated with uterine
leiomyomas.
METHODS: In a double-blind, double-dummy trial, premenopausal women with uterine
leiomyomas and heavy menstrual bleeding defined as a pictorial blood loss
assessment chart score of at least 120 were randomized in a 1:1 ratio to
relugolix (40 mg, oral, once daily) or leuprorelin acetate (1.88 mg or 3.75 mg,
monthly injection) for 24 weeks. The primary endpoint was the proportion of
patients with a total pictorial blood loss assessment chart score of less than
10 for weeks 6-12. Secondary endpoints included myoma and uterine volumes, and
hemoglobin levels. A sample size of 144 patients per group (n=288) was estimated
to provide at least 90% power to demonstrate noninferiority (prespecified
noninferiority margin -15%; one-sided 0.025 level of significance).
RESULTS: From March 2016 to September 2017, 281 patients were randomized
(relugolix, n=139, leuprorelin n=142). Demographic and baseline characteristics
were well balanced; mean pictorial blood loss assessment chart score was 254.3
in the relugolix group and 263.7 in the leuprorelin group. The proportion of
patients with total pictorial blood loss assessment chart score of less than 10
for weeks 6-12 was 82.2% in the relugolix group and 83.1% in the leuprorelin
group, demonstrating noninferiority of relugolix compared with leuprorelin
(relugolix-leuprorelin difference -0.9%; 95% CI: -10.10 to 8.35; prespecified
noninferiority margin -15%; P=.001). Reductions in myoma and uterine volumes and
increases in hemoglobin levels were comparable in the two groups. Relugolix was
associated with an earlier effect on menstrual bleeding than leuprorelin
(pictorial blood loss assessment chart score of less than 10, 64.2% vs 31.7%
[relugolix-leuprorelin difference 32.5%; 95% CI: 20.95-44.13%] for weeks 2-6 and
pictorial blood loss assessment chart score of 0, 52.6% vs 21.8% [30.7%; 95% CI:
19.45-42.00%] for weeks 2-6) and faster recovery of menses after treatment
discontinuation (relugolix median [Q1, Q3], 37 days [32.0, 46.0]; leuprorelin
median, 65 days [54.0, 77.0]). Adverse events and bone mineral density loss were
similar between relugolix and leuprorelin treatment groups.
CONCLUSION: In women with uterine leiomyomas, once-daily treatment with
relugolix, an oral gonadotropin-releasing hormone antagonist, demonstrated
noninferiority to monthly leuprorelin for improvement of heavy menstrual
bleeding at 6-12 weeks of treatment, had a more rapid effect on menstrual
bleeding, and was generally well tolerated.
CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02655237; JAPIC Clinical
Trial Information, JapicCTI-163128.
FUNDING SOURCE: Takeda Pharmaceutical Company Limited and an affiliate of
NovaQuest Capital Management LLC. The orally active nonpeptide gonadotropin-releasing hormone (GnRH)-receptor
antagonist relugolix (Relumina) is being developed by Takeda and ASKA
Pharmaceutical as a treatment for various sex hormone related disorders.
Relugolix was recently approved for marketing in Japan as a treatment for
symptoms associated with uterine fibroids, and studies evaluating the efficacy
of the drug as treatment for endometriosis-associated pain and prostate cancer
are currently underway. This article summarizes the milestones in the
development of relugolix leading to this first approval for the treatment of
symptoms associated with uterine fibroids. Uterine leiomyomas represent the most common form of benign gynecological tumors
affecting 20-40% of women during their life. Several therapeutic options are
available for treating these patients. The use of medical treatment for myomas
has largely grown in the last years, in particular for women who would refuse,
postpone or are not candidates for surgery. In the last years, the clinical
investigation of gonadotropin-releasing hormone (GnRH) antagonists (GnRH-ants)
has emerged. This class of drugs exerts pure competitive antagonistic activity
on the GnRH receptor at the pituitary gland, producing an immediate stop in the
release of gonadotropins and sex steroids. Relugolix is an orally active
nonpeptide GnRH-ant, recently licensed for marketing in Japan for the treatment
of symptoms related to uterine myomas. Currently, several phase III clinical
trials are ongoing to evaluate this molecule in this setting in the U.S. and
Europe. OBJECTIVE: To investigate the efficacy and safety of the oral
gonadotropin-releasing hormone receptor antagonist, relugolix, in patients
experiencing uterine fibroid-associated pain.
DESIGN: Phase 3, multicenter, randomized, double-blind, placebo-controlled
study.
SETTING: Medical centers.
PATIENT(S): Premenopausal Japanese women (N = 65) experiencing
moderate-to-severe uterine fibroid-associated pain with a maximum Numerical
Rating Scale (NRS) score of ≥4 were randomized and completed the study.
INTERVENTION(S): Once-daily 40 mg relugolix (n = 33) or placebo (n = 32) for
12 weeks.
MAIN OUTCOME MEASURE(S): Primary end point: proportion of patients with a
maximum NRS score of ≤1 during the 28-day period before the final dose of study
drug. Secondary end points: proportion of patients with no pain (NRS = 0) and
percentage of days without pain during the 28-day period before the final dose
of study drug; adverse events.
RESULT(S): More patients receiving relugolix versus placebo achieved a maximum
NRS score of ≤1 during the 28-day period before the final dose of study drug
(57.6% vs. 3.1%). Similarly, more patients receiving relugolix versus placebo
achieved a maximum NRS score of 0 (48.5% vs. 3.1%) and experienced more days
without pain (96.4% vs. 71.4%). More patients receiving relugolix versus placebo
experienced treatment-emergent adverse events (TEAEs; 87.9% vs. 56.3%); however,
the rate of treatment discontinuation was low and not different between groups.
Most TEAEs were mild to moderate in intensity. TEAEs (≥10%) included hot flush,
metrorrhagia, hyperhidrosis, and menorrhagia, consistent with relugolix's
mechanism of action, and viral upper respiratory tract infection.
CONCLUSION(S): Relugolix improved uterine fibroid-associated pain and was well
tolerated.
CLINICAL TRIAL REGISTRATION NUMBERS: NCT02655224.
JAPIC CLINICAL TRIAL INFORMATION: JapicCTI-163127. BACKGROUND: External beam radiotherapy (EBRT) with neoadjuvant/adjuvant androgen
deprivation therapy (ADT) is an established treatment option to prolong survival
for patients with intermediate- and high-risk prostate cancer (PCa). Relugolix,
an oral gonadotropin-releasing hormone (GnRH) receptor antagonist, was evaluated
in this clinical setting in comparison with degarelix, an injectable GnRH
antagonist.
OBJECTIVE: To evaluate the safety and efficacy of relugolix to achieve and
maintain castration.
DESIGN, SETTING, AND PARTICIPANTS: A phase 2 open-label study was conducted in
103 intermediate-risk PCa patients undergoing primary EBRT and
neoadjuvant/adjuvant ADT between June 2014 and December 2015.
INTERVENTION: Patients randomly assigned (3:2) to 24-wk treatment with either
daily oral relugolix or 4-wk subcutaneous depot degarelix (reference control).
OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was the rate
of effective castration (testosterone <1.73nmol/l) in relugolix patients between
4 and 24 wk of treatment. Secondary endpoints included rate of profound
castration (testosterone <0.7nmol/l), prostate-specific antigen (PSA) levels,
prostate volume, quality of life (QoL) assessed using the Aging Males' Symptoms
scale, and the European Organization for Research and Treatment of Cancer
(EORTC) Quality of Life (30-item EORTC core questionnaire [EORTC QLQ-C30] and
25-item EORTC prostate cancer module [EORTC QLQ-PR25]) questionnaires, and
safety. No formal statistical comparisons with degarelix were planned.
RESULTS AND LIMITATIONS: Castration rates during treatment were 95% and 82% with
relugolix and 89% and 68% with degarelix for 1.73 and 0.7nmol/l thresholds,
respectively. Median time to castration in the relugolix arm was 4 d. During
treatment, PSA levels and prostate volumes were reduced in both groups. Three
months after discontinuing treatment, 52% of men on relugolix and 16% on
degarelix experienced testosterone recovery (statistical significance of
differences not tested). Mean and median QoL scores improved following treatment
discontinuation. The most common adverse event was hot flush (relugolix 57%;
degarelix 61%). Lack of blinding was a potential limitation.
CONCLUSIONS: Relugolix achieved testosterone suppression to castrate levels
within days and maintained it over 24 wk with a safety profile consistent with
its mechanism of action.
PATIENT SUMMARY: Oral once-daily relugolix may be a novel oral alternative to
injectable androgen deprivation therapies. Results from the phase 3 HERO trial(NCT03085095), presented during the 2020
American Society of Clinical Oncology Virtual Scientific Program, indicated that
relugolix (Relumina) demonstrated superiority over leuprolide (Lupron) in
sustained testosterone suppression through 48 weeks, fast testosterone recovery
after discontinuation, and a 50% reduction in major adverse cardiovascular
events (MACE) in patients with advanced prostate cancer. INTRODUCTION: Uterine fibroids (UF) are benign tumors common in premenopausal
women, with strong impact on the health-care systems. For many years, surgery
represented the only therapy for symptomatic fibroids. However, clinicians are
observing a switch from surgery to noninvasive methods; in particular, medical
treatment has been shown to be efficacious in obtaining a bleeding reduction and
in ameliorating patient conditions.
AREAS COVERED: The authors review the current options available for the
treatment of women with UF, with a special focus on the newest one, relugolix.
It is an orally active non-peptide Gonadotropin-releasing hormone
(GnRH)-receptor antagonist recently licensed for women with symptomatic
fibroids. Relugolix is a well-tolerated safe drug; it is effective in inducing a
dose-dependent decrease in menstrual blood loss, with faster reduction of heavy
menstrual bleeding (HMB) and a greater shrinkage in fibroid volume compared to
the current standard of GnRH agonist treatment.
EXPERT OPINION: Relugolix is a promising drug for the non-surgical treatment of
women with UF. To date, the only published data come from a well-selected
Japanese female population study while results from worldwide ongoing studies
are ongoing in order to confirm the efficacy of this GnRH agonist receptor. We here describe a case of the prolapse of pedunculated submucosal leiomyoma
through the cervix during the treatment of a gonadotropin-releasing hormone
(GnRH) antagonist relugolix. We also present the literature review of the cases
of leiomyoma prolapse during GnRH modulators. A 55-year-old woman with atypical
vaginal bleeding diagnosed submucosal uterine fibroid 6 cm in diameter, and
daily oral administration of relugolix was conducted. On the 35th day of the
administration, heavy vaginal bleeding suddenly occurred due to leiomyoma
prolapse. Finally, she underwent abdominal hysterectomy to treat heavy bleeding.
To date, six cases of leiomyoma prolapse during GnRH modulators have been
reported, in which all the previous cases were treated with GnRH agonists. This
is the first case report of leiomyoma prolapse during GnRH antagonist treatment.
Notably, leiomyoma prolapse is a possible common adverse effect of GnRH
modulators for the treatment of submucosal leiomyoma, which is caused by rapid
decrease in its volume. OBJECTIVE: To evaluate the efficacy and safety of three dose levels of
relugolix, a gonadotropin-releasing hormone receptor antagonist, compared with
placebo and leuprorelin in women with endometriosis-associated pain.
DESIGN: Phase 2, multicenter, randomized, double-blind, placebo-controlled
study.
SETTING: Hospitals and clinics.
PATIENT(S): Adult premenopausal women with endometriosis who had dysmenorrhea
and endometriosis-associated pelvic pain.
INTERVENTION(S): During a 12-week treatment period, patients received relugolix
10 mg (n = 103), 20 mg (n = 100), or 40 mg (n = 103) as a daily oral dose;
placebo (n = 97) as a daily oral dose; or leuprorelin 3.75 mg (n = 80) as a
monthly subcutaneous injection.
MAIN OUTCOME MEASURE(S): Primary endpoint was the change from baseline in mean
visual analog scale score for pelvic pain during 28 days before the end of
treatment.
RESULT(S): The mean changes in mean visual analog scale score for pelvic pain
were -3.8 mm in the placebo group; -6.2, -8.1, and -10.4 mm in the relugolix
10-mg, 20-mg, and 40-mg groups; respectively; and -10.6 mm in the leuprorelin
group. The major adverse events with relugolix were hot flush, metrorrhagia,
menorrhagia, and irregular menstruation, and bone mineral density decrease in a
dose-response manner, which were also observed in the leuprorelin group with a
frequency comparable with that in the relugolix 40-mg group.
CONCLUSION(S): Oral administration of relugolix alleviated
endometriosis-associated pain in a dose-response manner and was generally well
tolerated. Relugolix 40 mg demonstrated efficacy and safety comparable with
those of leuprorelin.
CLINICAL TRIAL REGISTRATION NUMBER: NCT01458301. |
What is the effect of Carbendazim on bees? | Carbendazim is an environmental risk factor that likely weakens bee colonies, partially due to reduced expression of major royal jelly proteins, which may be potential causes of colony collapse disorder. | Publisher: Los abejorros están constantemente expuestos a una amplia gama de
agentes estresantes bióticos y abióticos de los que deben defenderse para
sobrevivir. Los patógenos y los pesticidas son importantes factores estresantes
que influyen en la salud de los abejorros, tanto cuando actúan solos como en
combinación. Para tener un mejor conocimiento sobre la salud de los abejorros,
debemos investigar cómo interactúan estos factores estresantes, pero los
estudios experimentales hasta la fecha generalmente se centran en estudiar solo
uno o dos factores. El objetivo de nuestro estudio es evaluar cómo los efectos
combinados de cuatro importantes factores estresantes (el parásito intestinal
Nosema ceranae, el insecticida neonicotinoide tiametoxam, el insecticida
piretroide cipermetrina y el fungicida EBI tebuconazol) interactúan para afectar
a los abejorros a nivel individual y de colonia. Establecimos siete grupos de
tratamiento de colonias de abejorros que expusimos a diferentes combinaciones de
estos factores estresantes durante dos semanas en condiciones de laboratorio, y
posteriormente se colocaron en el campo durante siete semanas, para evaluar el
efecto de los tratamientos sobre la prevalencia de N. ceranae en abejorros
inoculados, los niveles de expresión de genes relacionados con la inmunidad y la
desintoxicación, la recolección de alimentos, el aumento de peso, el número de
obreras y machos, y la producción de cría de obreras, machos y reinas. La
exposición a mezclas de pesticidas redujo la recolección de alimentos por parte
de los abejorros. Todos los genes relacionados con la inmunidad se
sobre-expresaron en los abejorros inoculados con N. ceranae cuando no habían
estado expuestos a mezclas de pesticidas, y los abejorros expuestos al fungicida
y al piretroide presentaron menos probabilidades de tener N. ceranae. La
exposición combinada a la mezcla de tres pesticidas y N. ceranae redujo el
crecimiento de la colonia de abejorros y todos los tratamientos tuvieron efectos
perjudiciales en la producción de crías. Los grupos expuestos al insecticida
neonicotinoide produjeron entre un 40 y un 76% menos de reinas que las colonias
control. Nuestros hallazgos muestran que la exposición a combinaciones de
factores estresantes con los que los abejorros entran frecuentemente en contacto
tiene efectos perjudiciales sobre la salud y el rendimiento de la colonia y, por
lo tanto, podría tener un impacto a nivel poblacional. Estos resultados también
tienen importantes implicaciones para las prácticas y políticas actuales de
evaluación de riesgos y uso de plaguicidas, ya que las combinaciones probadas
aquí se aplican con frecuencia simultáneamente en el campo. Comprender las
interacciones entre los diferentes factores de estrés es fundamental para
mejorar nuestra capacidad de gestión de las poblaciones de abejas y así
garantizar los servicios de polinización en el futuro. Studying the sublethal effects of agrochemical pesticides on nontarget honeybees
(Apis mellifera) is important for agricultural development. Carbendazim is a
widely used broad-spectrum fungicide that inhibits mitotic microtubule formation
and cell division. However, the impact of carbendazim on bee health and
development has not been fully elucidated. Here, using proteomics approaches, we
assessed in vitro the changes in the expression of functional proteins in the
head of newly emerged adults following treatment with field concentration of
carbendazim during the larval stage. Treatment with carbendazim severely altered
266 protein expression patterns in the heads of adults and 218 of them showed
downregulation after carbendazim exposure. Notably, major royal jelly proteins,
a crucial multifunctional protein family with irreplaceable function in
sustaining the development of colonies, were significantly suppressed in
carbendazim-treated bees. This result was verified in both head and
hypopharyngeal gland of nurse bees. Moreover, visual and olfactory loss, immune
functions, muscular activity, social behavior, neural and brain development,
protein synthesis and modification, and metabolism-related proteins were likely
inhibited by carbendazim treatment. Together, these results suggest that
carbendazim is an environmental risk factor that likely weakens bee colonies,
partially due to reduced expression of major royal jelly proteins, which may be
potential causes of colony collapse disorder. |
What 3 organs are the sphincter of Oddi associated with? | Sphincter of Oddi is associated with the pancreatic duct, duodenum and gallbladder. | The sphincter of Oddi is a small sphincter which is strategically placed at the
junction of the bile duct and pancreatic duct with the duodenum. It regulates
the flow of bile and pancreatic juice into the duodenum and prevents reflux of
duodenal contents into the ducts. The structure of the sphincter of Oddi differs
from species to species and consequently its physiological action varies in
different species. Anatomical and immunohistochemical investigations have
demonstrated that the sphincter of Oddi is richly innervated by cholinergic,
adrenergic and peptidergic neurons. In addition, neural connections exist
between the sphincter, gallbladder and proximal gastrointestinal tract. These
nerves in addition to hormones are important in the control of sphincter of Oddi
motility and function. The normal human sphincter of Oddi is characterized by
prominent phasic contractions which are superimposed on a modest basal pressure.
These contractions are present throughout the interdigestive period. The
contractions and basal pressure are inhibited by ingestion of a meal or infusion
of cholecystokinin octapeptide, thus enhancing the flow of bile and pancreatic
juice into the duodenum. Sphincter of Oddi dysfunction has been described in
patients who present with recurrent biliary type pain and no evidence of a
structural cause for the pain. Motility disorders characterized as an elevated
basal pressure, rapid contraction frequency, paradoxical response to
cholecystokinin octapeptide or excess of retrograde contractions have been
identified. A number of pharmacologically active substances have been used in an
attempt to treat these patients. Such pharmaceuticals include nitrites, Ca2+
channel blockers and smooth muscle relaxants. Their effect is transient and side
effects relating to cardiovascular actions preclude their longterm use. Division
of the sphincter either endoscopically or by open operation has been
demonstrated by prospective clinical trials to be the most efficacious treatment
for patients with a stenosed sphincter manometrically demonstrated by a high
basal pressure. Improved understanding of the controlling mechanisms of
sphincter of Oddi motility and the pathophysiology of sphincter of Oddi
dysfunction should assist in the development of effective pharmacotherapy for
these disorders. Ever since its description approximately 100 years ago, the sphincter of Oddi
has been surrounded by controversy. First, whether it indeed existed, second,
whether it had a significant physiological role in man and more recently whether
abnormalities in its function give rise to a clinical syndrome. Data from animal
and human studies, using sensitive techniques, have helped define the
physiological role of the sphincter of Oddi, and more recent studies are
determining the factors which control sphincter of Oddi function. These studies
support Oddi's original description that the sphincter has a major role in the
control of flow of bile and pancreatic juice into the duodenum, and equally
importantly helps prevent the reflux of duodenal contents into the biliary and
pancreatic ductal systems. The controversy of whether abnormalities in sphincter
of Oddi motility result in clinical syndromes has not been totally resolved.
Part of the difficulty has been inability to document normal and hence abnormal
function of the sphincter. With the emergence of endoscopic biliary manometry as
a sensitive and reproducible technique, however, the motility of the human
sphincter of Oddi has come under closer scrutiny and allowed definition of
possible disorders. We have used the term sphincter of Oddi dysfunction to
define manometric abnormalities in patients who present with signs and symptoms
consistent with a biliary or pancreatic ductal origin. Based on the manometry,
we have subdivided the dysfunction into two groups; a group characterised by a
stenotic pattern - that is, raised sphincter basal pressure - and a second group
having a dyskinetic pattern - that is, paradoxical response to cholecystokinin
injection, rapid contraction frequency, high percentage of retrograde
contractions, or short periods of raised basal percentage of retrograde
contractions, or short periods of raised basal pressure. It is apparent from the
mamometry but also from the clinical data that the patients are a heterogeneous
group and thus any therapy would need to be tailored for each patient and
abnormality. The most recent therapeutic data suggest that patients with the
stenotic pattern on manometry respond to division of the sphincter, however,
those patients with the dyskinetic manometric pattern show no significant effect
after sphincterotomy. Further prospective trials evaluating therapeutic options
are under way and their results are eagerly awaited. The sphincter of Oddi is the smooth muscle connection between the bile duct and
the duodenum. Its physiological function is associated with a regular motility
characterized by phasic contractions superimposed on the sphincter of Oddi
baseline pressure. Recently introduced ERCP-manometry permits further studies of
sphincter of Oddi pharmacology. A number of drugs have so far been studied.
Sedatives of the diazepam type had no effect on the sphincter, while
butylscopolaminium bromide, a typical neurotropic agent, brings about cessation
of the sphincter motility for 3-8 minutes. Hymecromon lowered the sphincter
baseline pressure from 9.8 to 7.8 mmHg. A 1.2 mg sublingual dose of
nitroglycerin, a typical musculotropic agent, caused significant relaxation of
the sphincter, and decreased baseline pressure from 8.9 mmHg to 2.9 mmHg;
Sphincter motility was not affected. Morphine-like analgetics, in particular
pentazocine, elevated sphincter baseline pressure, but buprenorphine and
tramadol did not. Pharmacological doses of gastrointestinal hormones also affect
the sphincter; CCK octapeptide, glucagon and secretin are able to decrease
sphincter of Oddi baseline pressure, and CCK octapeptide abolishes sphincter
motility. Sphincter of Oddi pharmacology is of clinical interest. The
administration of sphincter-relaxing agents, in particular nitroglycerin and
butylscopolaminium bromide, enables the endoscopist to extract small common bile
duct stones without previous papillotomy. Analgetics that induce sphincter
contraction and thus hinder the flow of bile and pancreatic juice, may be
helpful for the treatment of pain in patients with pancreatico-biliary disease.
Investigations into the effect of CCK on the healthy and diseased sphincter
permit us to identify patients with sphincter dysfunction using a special
CCK-provocation test. The sphincter of Oddi (SO) is critically located at the junction of the common
bile duct (CBD), main pancreatic duct, and the duodenum. It is a high-pressure
zone with phasic contractions that regulate bile and pancreatic juice flow. The
SO is probably regulated by several gastrointestinal hormones, and its basal
pressure and phasic contractions can be elevated or decreased significantly by
exogenous drugs. Its role in gallstone formation is probably negligible, but
severing the SO allows one to extract CBD stones with an endoscope. Abnormal
function of the SO can cause biliarylike pain. Of patients with persistent pain
after cholecystectomy, 14% have abnormal SO manometric findings. Endoscopic or
surgical sphincterotomy can cure these patients of their pain. The SO may play a
significant role in the development of pancreatitis in certain patients, either
because of the relationship of the CBD orifice to the pancreatic duct orifice
created by the SO or because of the response of the SO to exogenous agents, such
as alcohol. Flow through the sphincter of Oddi was studied by a constant-pressure perfusion
apparatus, and by using a constant rate of infusion and measuring pressure
changes just proximal to the sphincter. Pressure changes from balloons placed in
the gastric antrum and duodenum were recorded. Despite considerable variation in
activity and behaviour, the following conclusions were reached.1. The sphincter
of Oddi appears to be partially autonomous but is readily affected by changes in
duodenal tone.2. Reflex inhibition of the sphincter of Oddi is seen on
electrical and mechanical stimulation of the gall-bladder but not with passive
pressure changes within the gall-bladder.3. This reflex is relayed through the
coeliac ganglion.4. There is a definite relationship between gastric antral
activity and flow through the sphincter of Oddi. This is more obvious when food
is present in the stomach.5. Mechanical or electrical stimulation of the
stomach, duodenum, or upper small bowel influences the tone of the sphincter of
Oddi. It has been reported that interdigestive motor activities occur in the
gallbladder and sphincter of Oddi as well as in the gastroduodenal tract and
truncal vagus nerves modulate the gastroduodenal motility pattern. In the
present study, the vagal branches which influence on the interdigestive motor
activity of these organs were determined in conscious dogs. In the normal dog,
interdigestive motor activities closely related to interdigestive migrating
motor complex (IMC) in the gastric antrum and descending duodenum were recorded
in the gallbladder and sphincter of Oddi. In dogs whose celiac branches of the
vagus nerve were chronically resected, cycle periods of interdigestive motor
activity in the stomach, duodenum, gallbladder and sphincter of Oddi
significantly prolonged as compared with those in the normal dog but the
interrelation of them persisted. Quiescent period in motility prolonged and the
active period shortened. Resection of the pyloric branches had no influence on
the interdigestive motor activities in all organs. The results imply that celiac
branches of the vagus nerve modulate the interdigestive motor activity in the
stomach, descending duodenum, gallbladder and sphincter of Oddi. We studied the role of the L-arginine-nitric oxide (NO) pathway in
non-adrenergic, non-cholinergic (NANC) relaxation of the rabbit sphincter of
Oddi by recording changes in isometric tension in response to electrical field
stimulation in two series of experiments. In a first set of experiments, biliary
sphincters of Oddi removed from New Zealand white rabbits were placed
horizontally in an organ bath containing oxygenized, buffered (pH 7.4) Krebs
solution. Contractile responses of the whole sphincter to field stimulation were
determined. In the second set of experiments, sphincter of Oddi was divided into
two parts and the effects of field stimulation were studied separately on areas
close to the duodenal papilla (area I) and areas close to the common bile duct
(area II). In the whole sphincter of Oddi, field stimulation induced an initial
twitch-like contraction followed by relaxation proportional to the number of
stimuli (3 and 10 stimuli at 20 Hz, 50 V, 0.1 ms). The magnitude of the
contractile responses was considerably reduced by 1 microM atropine,
phentolamine and oxprenolol (NANC solution). Field stimulation produced
dose-dependent contractions of both segments of sphincter of Oddi in response to
the same protocol as used with whole sphincter of Oddi. However, preincubation
with NANC solution produced monophasic relaxations in response to field
stimulation in area I, whereas area II preparations such as the whole sphincter
of Oddi responded with contractions followed by minimal relaxations. Field
stimulation failed to induce either contractions or relaxations in the presence
of 1 microM tetrodotoxin.(ABSTRACT TRUNCATED AT 250 WORDS) BACKGROUND: This study investigated the existence of direct neural connections
between the duodenum and the biliary tract in the Australian possum.
METHODS: Retrogradely transported neuronal dyes, Fast Blue and Dil, were
injected into the wall of the gallbladder and the sphincter of Oddi. The
duodenum, biliary tract, and sympathetic and sensory ganglia were examined for
the presence of labeled cell bodies.
RESULTS: Two to 3 weeks after gallbladder injection, labeled nerve cell bodies
were found in the myenteric plexus of the proximal duodenum but were rare in the
duodenum distal to the sphincter of Oddi. No neurons were found in the submucous
plexus. Labeled nerve cells were also found in the sphincter of Oddi. After
injection of the sphincter, labeled neurons were in both the submucous and
myenteric plexuses of the duodenum, on either side. Approximately one third of
labeled myenteric neurons were immunoreactive for enkephalin. Labeled cell
bodies were also in the coeliaco-mesenteric, nodose, and dorsal root ganglia
after both gallbladder and sphincter injection. After a myotomy on the proximal
duodenum, no neurons were labeled on the pyloric side of the lesion by
subsequent sphincter injection of dye.
CONCLUSIONS: Direct neural pathways connect the duodenum with the gallbladder
and the sphincter of Oddi, and the sphincter with the gallbladder; this implies
that enteric nerve circuits participate in coordinating duodenal and biliary
functions. We have investigated the existence of neural connections between the duodenum
and the sphincter of Oddi (SO). Stimulation of duodenal myenteric fiber bundles
elicited synaptic responses in SO neurons, which included nicotinic fast
excitatory postsynaptic potentials (EPSPs), slow EPSPs, and
alpha(2)-adrenoreceptor-mediated inhibitory postsynaptic potentials. After 48 h
in organ culture, when extrinsic fibers had diminished, only the fast EPSPs
persisted. Duodenal mucosal stimulation also elicited nicotinic fast EPSPs in SO
neurons. There was no association between the SO neurons that received duodenal
input and their chemical coding. A reciprocal projection also exists from the SO
to the duodenum. In acute and cultured preparations, duodenal myenteric
stimulation caused antidromic responses in 20% of SO neurons. Furthermore, 45.6
+/- 10.5 neurons in SO ganglia were retrogradely labeled from dye application
sites in the duodenum. It is proposed that bidirectional neural communication
occurs between the duodenum and the SO and that duodenal neurons provide
excitatory fast synaptic input to SO neurons through a reflex that can be
activated at the duodenal mucosa. Magnetic resoce (MR) cholangiopancreatography has proved a robust and
noninvasive imaging modality for evaluating the biliary and pancreatic ducts
without the use of ionizing radiation. Although MR cholangiopancreatography
reliably depicts the main extrahepatic and intrahepatic bile ducts, it does not
depict the segmental intrahepatic ducts unless they are dilated. The segmental
ducts are difficult to visualize with MR cholangiopancreatography because of
their small caliber and the limited spatial resolution and signal-to-noise ratio
achievable with standard MR pulse sequences. However, visualization of the
normal (ie, nondistended) biliary system is necessary for the evaluation of
donor candidates for living related liver transplantation. Because of the
prevalence of variant biliary anatomy, MR cholangiopancreatography is often used
for preoperative evaluation of prospective liver donors. Intravenous morphine
administered prior to MR cholangiopancreatography can improve image quality by
causing the sphincter of Oddi to contract, which increases pressure in and
distention of the biliary and pancreatic ducts. Morphine administration may also
be particularly helpful for the evaluation of patients with primary sclerosing
cholangitis, maligt neoplasms such as cholangiocarcinoma, or cystic and
non-organ-deforming benign pancreatic neoplasms. The most common functional disorder of the biliary tract and pancreas relates to
the activity of the Sphincter of Oddi. The Sphincter of Oddi is a small smooth
muscle sphincter strategically placed at the junction of the bile duct,
pancreatic duct, and duodenum. The sphincter controls flow of bile and
pancreatic juices into the duodenum and prevents reflux of duodenal content into
the ducts. Disorder in its motility is called Sphincter of Oddi dysfunction.
Clinically this presents either with recurrent abdominal biliary type pain or
episodes of recurrent pancreatitis. Manometry may identify the motility
abnormalities, the most clinically significant being an abnormally elevated
basal pressure. The most effective treatment once an abnormal basal pressure is
identified is division of the sphincter. This is associated with good long-term
results. |
List clinical phenotypes and molecular genetic features of patients with KMT2B-related disorders | Atypical patterns of dystonia evolution and a subgroup of patients presents with a non-dystonic neurodevelopmental phenotype. In addition to the previously reported systemic features there seem to be co-morbidities, including the risk of status dystonicus, intrauterine growth retardation, and endocrinopathies. | |
What is the use of Atogepant? | Atogepant is used for preventive treatment of migraine. | The incidence of migraine is higher among women than men and peaks during the
reproductive years, when contraceptive medication use is common. Atogepant, a
potent, selective antagonist of the calcitonin gene-related peptide receptor-in
development for migraine prevention-is thus likely to be used by women taking
oral contraceptives. This phase 1, open-label, single-center, 2-period,
fixed-sequence study examined the effect of multiple-dose atogepant 60 mg once
daily on the single-dose pharmacokinetics of a combination oral contraceptive,
ethinyl estradiol 0.03 mg and levonorgestrel 0.15 mg (EE/LNG), in healthy
postmenopausal or oophorectomized women. For participants in period 1, a single
dose of EE/LNG was followed by a 7-day washout. In period 2, atogepant was given
once daily on days 1-17; an oral dose of EE/LNG was coadministered with
atogepant on day 14. Plasma pharmacokinetic parameters for EE and LNG were
assessed following administration with and without atogepant. Twenty-six
participants aged 45-64 years enrolled; 22 completed the study in accordance
with the protocol. The area under the concentration-time curve extrapolated to
infinity (AUC0-∞ ) of LNG was increased by 19% when administered with atogepant.
Coadministration of atogepant and a single dose of EE/LNG did not substantially
alter the pharmacokinetics of EE; the ∼19% increase in plasma AUC0-∞ of LNG is
not anticipated to be clinically significant. Overall, atogepant alone and in
combination with EE/LNG was generally well tolerated, with no new safety signals
identified. Introduction: Migraine is one of the most common neurological disorders.
Nowadays, the 5-HT1B/1D receptor agonists, namely triptans, are considered as
the standard of care for migraine acute treatment. However, triptans have
limitations in some patients, such as incomplete pain relief, headache
recurrence, and cardiovascular contraindications. New 5-HT1F receptor agonists,
namely ditans, and calcitonin gene-related peptide receptor antagonists, namely
gepants, have been developed as migraine-specific treatments.Areas covered: This
paper reviews the available data from RCTs to assess the clinical efficacy,
safety, and tolerability profile of lasmiditan, rimegepant, and ubrogepant for
the acute treatment of migraine and atogepant for the prevention of
migraine.Expert opinion: Available data suggest that lasmiditan, rimegepant, and
ubrogepant might not have a clinical efficacy similar to triptans. Lasmiditan
did not cause the typical triptan side effects but was associated with central
nervous system side effects, causing temporary driving impairment. On the
contrary, the new generation of gepants showed a placebo-like tolerability
profile and the absence of a specific pattern of side effects. Future studies on
lasmiditan and gepants with respect to established effective comparators are
mandatory to support phase III results and to help clinicians to balance the
benefit/risk profiles of the various acute and preventive medications. BACKGROUND: Atogepant is an oral, small-molecule, calcitonin gene-related
peptide receptor antagonist that is being investigated for the preventive
treatment of migraine.
METHODS: In a phase 3, double-blind trial, we randomly assigned adults with 4 to
14 migraine days per month in a 1:1:1:1 ratio to receive a once-daily dose of
oral atogepant (10 mg, 30 mg, or 60 mg) or placebo for 12 weeks. The primary end
point was the change from baseline in the mean number of migraine days per month
across the 12 weeks. Secondary end points included headache days per month, a
reduction from baseline of at least 50% in the 3-month average of migraine days
per month, quality of life, and scores on the Activity Impairment in
Migraine-Diary (AIM-D).
RESULTS: A total of 2270 participants were screened, 910 were enrolled, and 873
were included in the efficacy analysis; 214 were assigned to the 10-mg atogepant
group, 223 to the 30-mg atogepant group, 222 to the 60-mg atogepant group, and
214 to the placebo group. The mean number of migraine days per month at baseline
ranged from 7.5 to 7.9 in the four groups. The changes from baseline across 12
weeks were -3.7 days with 10-mg atogepant, -3.9 days with 30-mg atogepant, -4.2
days with 60-mg atogepant, and -2.5 days with placebo. The mean differences from
placebo in the change from baseline were -1.2 days with 10-mg atogepant (95%
confidence interval [CI], -1.8 to -0.6), -1.4 days with 30-mg atogepant (95% CI,
-1.9 to -0.8), and -1.7 days with 60-mg atogepant (95% CI, -2.3 to -1.2)
(P<0.001 for all comparisons with placebo). Results for the secondary end points
favored atogepant over placebo with the exceptions of the AIM-D Performance of
Daily Activities score and the AIM-D Physical Impairment score for the 10-mg
dose. The most common adverse events were constipation (6.9 to 7.7% across
atogepant doses) and nausea (4.4 to 6.1% across atogepant doses). Serious
adverse events included one case each of asthma and optic neuritis in the 10-mg
atogepant group.
CONCLUSIONS: Oral atogepant once daily was effective in reducing the number of
migraine days and headache days over a period of 12 weeks. Adverse events
included constipation and nausea. Longer and larger trials are needed to
determine the effect and safety of atogepant for migraine prevention. (Funded by
Allergan; ADVANCE ClinicalTrials.gov number, NCT03777059.). Conflict of interest statement: Declaration of conflicting interests: The
authors declared the following potential conflicts of interest with respect to
the research, authorship, and/or publication of this article: Todd J Schwedt
serves on the Board of Directors for the American Headache Society and the
International Headache Society. He has received research support from the
American Migraine Foundation, Amgen, Henry Jackson Foundation, National
Institutes of Health, Patient-Centered Outcomes Research Institute, and US
Department of Defense. Within the past 12 months, he has received personal
compensation for serving as a consultant or advisory board member for
AbbVie/Allergan, Biohaven, Eli Lilly, Equinox, Lundbeck, and Novartis. He has
received royalties from UpToDate. He holds stock options in Aural Analytics and
Nocira. Richard B Lipton has received research support from the National
Institutes of Health, the FDA, and the National Headache Foundation. He serves
as consultant, advisory board member, or has received honoraria or research
support from AbbVie/Allergan, Amgen, Biohaven, Dr. Reddy’s Laboratories
(Promius), electroCore, Eli Lilly, GlaxoSmithKline, Lundbeck, Merck, Novartis,
Teva, Vector, and Vedanta Research. He receives royalties from Wolff’s Headache,
8th edition (Oxford University Press, 2009), and Informa. He holds stock/options
in Biohaven and Ctrl M. Jessica Ailani has served as a consultant for AbbVie,
Amgen, Axsome, Ctrl M, Eli Lilly and Company, Lundbeck, Impel, Satsuma,
Theranica, Teva, and Vorso; has served as a speaker for AbbVie, Amgen, Eli Lilly
and Company, Lundbeck, and Teva; has received honoraria from Medscape; and has
provided editorial services to Current Pain and Headache Reports, NeurologyLive,
and SELF magazine. Her institute has received clinical trial support from
AbbVie, the American Migraine Foundation, Biohaven, Eli Lilly and Company,
Satsuma, and Zosano. Stephen D Silberstein is a consultant and/or advisory panel
member for and has received honoraria from AbbVie, Alder Biopharmaceuticals,
Amgen, Avanir, eNeura, electroCore Medical, Labrys Biologics, Medscape,
Medtronic, Neuralieve, NINDS, Pfizer, and Teva. His employer receives research
support from AbbVie, Amgen, Cumberland Pharmaceuticals, electroCore Medical,
Labrys Biologics, Eli Lilly, Mars, and Troy Healthcare. Cristina Tassorelli has
participated in advisory boards for AbbVie, electroCore, Eli Lilly, Novartis,
and Teva. She has lectured at symposia sponsored by AbbVie, Eli Lilly, Novartis,
and Teva. She is principal investigator or collaborator in clinical trials
sponsored by Alder, Eli Lilly, IBSA, Novartis, and Teva. She has received
research grants from the European Commission, the Italian Ministry of Health,
the Italian Ministry of University, the Migraine Research Foundation, and the
Italian Multiple Sclerosis Foundation. Hua Guo, Kaifeng Lu, Brett Dabruzzo, Rosa
Miceli, Lawrence Severt, Michelle Finnegan and Joel M Trugman are employees of
AbbVie and may hold AbbVie stock. In this issue of JNO Drs. M. Tariq Bhatti and Mark L. Moster discuss the
following 6 articles: Dinah Zur, Michaella Goldstein, Barequet D, Oron Y,
Elkayam O, Karni A, Wilf-Yarkoni A, Regev K, Habot-Wilner Z. Susac's syndrome-A
new ocular finding and disease outcome. Eye (Lond). 2021. doi:
10.1038/s41433-021-01464-7. Epub ahead of print.Durbant E, Radoi C, Garcia T,
Denoyer A, Arndt C. Intravitreal triamcinolone injections in non-arteritic
anterior ischemic optic neuropathy-A retrospective report. J Fr Ophtalmol.
2021;44:777-785.Cavanaugh MR, Blanchard LM, McDermott M, Lam BL, Tamhankar M,
Feldon SE. Efficacy of Visual Retraining in the Hemianopic Field after Stroke:
Results of a Randomized Clinical Trial. Ophthalmology. 2021;128:1091-1101.Czihal
M, Lottspeich C, Köhler A, Prearo I, Hoffmann U, Priglinger SG, Mackert MJ.
Transocular sonography in acute arterial occlusions of the eye in elderly
patients: Diagnostic value of the spot sign. PLoS One. 2021;16:e0247072.Ailani
J, Lipton RB, Goadsby PJ, Guo H, Miceli R, Severt L, Finnegan M, Trugman JM;
ADVANCE Study Group. Atogepant for the Preventive Treatment of Migraine. N Engl
J Med. 2021;385:695-706.Engelter ST, Traenka C, Gensicke H, Schaedelin SA, Luft
AR, Simonetti BG, Fischer U, Michel P, Sirimarco G, Kägi G, Vehoff J, Nedeltchev
K, Kahles T, Kellert L, Rosenbaum S, von Rennenberg R, Sztajzel R, Leib SL, Jung
S, Gralla J, Bruni N, Seiffge D, Feil K, Polymeris AA, Steiner L, Hamann J,
Bonati LH, Brehm A, De Marchis GM, Peters N, Stippich C, Nolte CH, Christensen
H, Wegener S, Psychogios MN, Arnold M, Lyrer P; TREAT-CAD investigators. Aspirin
vs. anticoagulation in cervical artery dissection (TREAT-CAD): an open-label,
randomised, non-inferiority trial. Lancet Neurol. 2021;20:341-350. Atogepant (Qulipta™) is an orally administered, small-molecule, calcitonin
gene-related peptide (CGRP) receptor antagonist being developed by AbbVie for
the prophylaxis of migraine. In September 2021, atogepant was approved in the
USA for the preventive treatment of episodic migraine in adults. The drug is
also in phase 3 clinical development for the preventive treatment of migraine in
various other countries. This article summarizes the milestones in the
development of atogepant leading to this first approval for the preventive
treatment of episodic migraine in adults. |
Is SMOC2 expressed during wound healing? | Yes,
SMOC2 response to wounding. | Author information:
(1)Developmental Biology and Stem Cells Department, Institute of Genetics and of
Molecular and Cellular Biology (IGBMC), 1 rue Laurent Fries, BP 10142, 67404,
Illkirch, France.
(2)Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.
(3)Institut National de la Santé et de la Recherche Médicale, INSERM U1258,
Illkirch, France.
(4)Université de Strasbourg, Illkirch, France.
(5)Faculty of Dentistry, Pediatrics Division, Preventive Department, Khon Kaen
University, Khon Kaen, Thailand.
(6)Faculté de Chirurgie Dentaire, Université de Strasbourg, 8 rue Ste Elisabeth,
67000, Strasbourg, France.
(7)Hôpitaux Universitaires de Strasbourg, Pôle de Médecine et Chirurgie
Bucco-Dentaires, Centre de Référence des Maladies Rares Orales et Dentaires,
CRMR O Rares, Filière TETECOU, ERN CRANIO, 1 place de l'Hôpital, 67000,
Strasbourg, France.
(8)Regenerative NanoMedicine, INSERM UMR1260, FMTS, Hôpitaux Universitaires de
Strasbourg, 11 rue Humann, 67000, Strasbourg, France.
(9)Biomaterials and Bioengineering, Université de Strasbourg, INSERM UMR1121, 11
rue Humann, 67000, Strasbourg, France.
(10)Hubrecht Institute, University Medical Center Utrecht, and University
Utrecht, Utrecht, The Netherlands.
(11)Faculté de Médecine, Université de Strasbourg, FMTS, 4 Rue Kirschleger,
67000, Strasbourg, France.
(12)Developmental Biology and Stem Cells Department, Institute of Genetics and
of Molecular and Cellular Biology (IGBMC), 1 rue Laurent Fries, BP 10142, 67404,
Illkirch, France. [email protected].
(13)Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.
[email protected].
(14)Institut National de la Santé et de la Recherche Médicale, INSERM U1258,
Illkirch, France. [email protected].
(15)Université de Strasbourg, Illkirch, France. [email protected].
(16)Faculté de Chirurgie Dentaire, Université de Strasbourg, 8 rue Ste
Elisabeth, 67000, Strasbourg, France. [email protected].
(17)Hôpitaux Universitaires de Strasbourg, Pôle de Médecine et Chirurgie
Bucco-Dentaires, Centre de Référence des Maladies Rares Orales et Dentaires,
CRMR O Rares, Filière TETECOU, ERN CRANIO, 1 place de l'Hôpital, 67000,
Strasbourg, France. [email protected].
(18)Eastman Dental Institute, University College London, London, UK.
[email protected].
(19)Developmental Biology and Stem Cells Department, Institute of Genetics and
of Molecular and Cellular Biology (IGBMC), 1 rue Laurent Fries, BP 10142, 67404,
Illkirch, France. [email protected].
(20)Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.
[email protected].
(21)Institut National de la Santé et de la Recherche Médicale, INSERM U1258,
Illkirch, France. [email protected].
(22)Université de Strasbourg, Illkirch, France. [email protected].
(23)Faculté de Chirurgie Dentaire, Université de Strasbourg, 8 rue Ste
Elisabeth, 67000, Strasbourg, France. [email protected]. The endometrium is a dynamic tissue that exhibits remarkable resilience to
repeated episodes of differentiation, breakdown, regeneration, and remodeling.
Endometrial physiology relies on a complex interplay between the stromal and
epithelial compartments with the former containing a mixture of fibroblasts,
vascular, and immune cells. There is evidence for rare populations of putative
mesenchymal progenitor cells located in the perivascular niche of human
endometrium, but the existence of an equivalent cell population in mouse is
unclear. We used the Pdgfrb-BAC-eGFP transgenic reporter mouse in combination
with bulk and single-cell RNA sequencing to redefine the endometrial mesenchyme.
In contrast to previous reports we show that CD146 is expressed in both
PDGFRβ + perivascular cells and CD31 + endothelial cells. Bulk RNAseq revealed
cells in the perivascular niche which express the high levels of Pdgfrb as well
as genes previously identified in pericytes and/or vascular smooth muscle cells
(Acta2, Myh11, Olfr78, Cspg4, Rgs4, Rgs5, Kcnj8, and Abcc9). scRNA-seq
identified five subpopulations of cells including closely related
pericytes/vascular smooth muscle cells and three subpopulations of fibroblasts.
All three fibroblast populations were PDGFRα+/CD34 + but were distinct in their
expression of Ngfr/Spon2/Angptl7 (F1), Cxcl14/Smoc2/Rgs2 (F2), and
Clec3b/Col14a1/Mmp3 (F3), with potential functions in the regulation of immune
responses, response to wounding, and organization of extracellular matrix,
respectively. Immunohistochemistry was used to investigate the spatial
distribution of these populations revealing F1/NGFR + cells in most abundance
beside epithelial cells. We provide the first definitive analysis of mesenchymal
cells in the adult mouse endometrium identifying five subpopulations providing a
platform for comparisons between mesenchymal cells in endometrium and other
adult tissues which are prone to fibrosis. BACKGROUND: Asthma is a common chronic respiratory disease that influences 300
million people all over the world. However, the pathogenesis of asthma has not
been fully elucidated. It has been reported that transforming growth factor-β
(TGF-β) can activate myofibroblasts. Moreover, the fibroblast to myofibroblast
transformation (FMT) can be triggered by TGF-β, which is a major mediator of
subepithelial fibrosis. Secreted modular calcium-binding protein 2 (SMOC2) is a
member of cysteine (SPARC) family and is involved in the progression of multiple
diseases. However, its role in asthma remains poorly understood. RT-qPCR
evaluated the expression of SMOC2. Bromodeoxyuridine assay and wound-healing
assay detected the proliferation and migration of lung fibroblasts,
respectively. IF staining was performed to assess the expression of α-smooth
muscle actin (α-SMA). Western blot analysis detected the levels of proteins.
Flow cytometry was utilized for determination of the number of myofibroblasts.
RESULTS: We found the expression of SMOC2 was upregulated by the treatment of
TGF-β1 in lung fibroblasts. In addition, SMOC2 promoted the proliferation and
migration of lung fibroblasts. More importantly, SMOC2 accelerated FMT of lung
fibroblasts. Furthermore, SMOC2 was verified to control the activation of AKT
and ERK. Rescue assays showed that the inhibition of AKT and ERK pathway
reversed the promoting effect of SMOC2 overexpression on proliferation,
migration and FMT in lung fibroblasts.
CONCLUSIONS: This work demonstrated that SMOC2 modulated TGF-β1-induced
proliferation, migration and FMT in lung fibroblasts and may promote asthma,
which potentially provided a novel therapeutic target for the management of
asthma. |
What is a potential alternate uses(repositioning) for Primaquine | Primaquine Diphosphate, a Known Antimalarial Drug, Blocks Vascular Leakage Acting Through Junction Stabilization. PD could be used as a novel drug for vascular leakage by maintaining endothelial integrity | Drug repositioning identifies new indications for known drugs. Here we report
repositioning of the malaria drug amodiaquine as a potential anti-cancer agent.
While most repositioning efforts emerge through serendipity, we have devised a
computational approach, which exploits interaction patterns shared between
compounds. As a test case, we took the anti-viral drug brivudine (BVDU), which
also has anti-cancer activity, and defined ten interaction patterns using our
tool PLIP. These patterns characterise BVDU's interaction with its target s.
Using PLIP we performed an in silico screen of all structural data currently
available and identified the FDA approved malaria drug amodiaquine as a
promising repositioning candidate. We validated our prediction by showing that
amodiaquine suppresses chemoresistance in a multiple myeloma cancer cell line by
inhibiting the chaperone function of the cancer target Hsp27. This work proves
that PLIP interaction patterns are viable tools for computational repositioning
and can provide search query information from a given drug and its target to
identify structurally unrelated candidates, including drugs approved by the FDA,
with a known safety and pharmacology profile. This approach has the potential to
reduce costs and risks in drug development by predicting novel indications for
known drugs and drug candidates. As a subtype of acute myeloid leukemia (AML), acute promyelocytic leukemia (APL)
is characterized by a chromosomal translocation, most of which result in the
production of a PML-RAR alpha fusion protein. Although the overall survival rate
of APL patients has improved dramatically due to all-trans retinoic acid (ATRA)
treatment, ATRA-resistance remains a clinical challenge in the management of
APL. Therefore, alternative agents should be considered for ATRA-resistant APL
patients. Here, we report that antimalaria drug primaquine phosphate (PRQ)
exhibits an anti-leukemia effect on both ATRA-sensitive cell line NB4 and
ATRA-resistant APL cell lines, NB4-LR2, NB4-LR1, and NB4-MR2. Moreover, PRQ
significantly inhibited primary colony formation of untreated or relapsed APL
patients. Further study showed that PRQ could induce the apoptosis of APL cells
by inhibiting NF-κB signaling pathway. The in vivo study showed that PRQ
significantly inhibited NB4-LR2 xenograft tumors growth. These results suggest
that PRQ is a potential therapeutic agent for ATRA-resistant APL patients. Endothelial barrier integrity is important for vascular homeostasis, and
hyperpermeability participates in the progression of many pathological states,
such as diabetic retinopathy, ischemic stroke, chronic bowel disease, and
inflammatory disease. Here, using drug repositioning, we discovered that
primaquine diphosphate (PD), previously known as an antimalarial drug, was a
potential blocker of vascular leakage. PD inhibited the linear pattern of
vascular endothelial growth factors (VEGF)-induced disruption at the cell
boundaries, blocked the formation of VEGF-induced actin stress fibers, and
stabilized the cortactin actin rings in endothelial cells. PD significantly
reduced leakage in the Miles assay and mouse model of streptozotocin
(STZ)-induced diabetic retinopathy. Targeted prediction programs and
deubiquitinating enzyme activity assays identified a potential mechanism of
action for PD and demonstrated that this operates via ubiquitin specific
protease 1 (USP1). USP1 inhibition demonstrated a conserved barrier function by
inhibiting VEGF-induced leakage in endothelial permeability assays. Taken
together, these findings suggest that PD could be used as a novel drug for
vascular leakage by maintaining endothelial integrity. Triple-negative breast cancer (TNBC) cells overexpress the epidermal growth
factor receptor (EGFR). Nuclear EGFR (nEGFR) drives resistance to anti-EGFR
therapy and is correlated with poor survival in breast cancer. Inhibition of
EGFR nuclear translocation may be a reasonable approach for the treatment of
TNBC. The anti-malarial drugs chloroquine and primaquine have been shown to
promote an anticancer effect. The aim of the present study was to investigate
the effect and mechanism of chloroquine- and primaquine-induced apoptosis of
breast cancer cells. We showed that primaquine, a malaria drug, inhibits the
growth, migration, and colony formation of breast cancer cells in vitro, and
inhibits tumor growth in vivo. Primaquine induces damage to early endosomes and
inhibits the nuclear translocation of EGFR. Primaquine inhibits the interaction
of Stat3 and nEGFR and reduces the transcript and protein levels of c-Myc.
Moreover, primaquine and chloroquine induce the apoptosis of breast cancer cells
through c-Myc/Bcl-2 downregulation, induce early endosome damage and reduce
nEGFR levels, and induce apoptosis in breast cancer through
nEGFR/Stat3-dependent c-Myc downregulation. Our study of primaquine and
chloroquine provides a rationale for targeting EGFR signaling components in the
treatment of breast cancer. |
Does daily atemoya juice intake change the pharmacokinetics of CYP1A2 substrates? | No, atemoya juice does not change the pharmacokinetics of CYP1A2 substrates. | BACKGROUND AND OBJECTIVES: Atemoya (Annona atemoya) is increasingly being
consumed worldwide because of its pleasant taste. However, only limited
information is available concerning possible atemoya-drug interactions. In the
present study, the issue of whether atemoya shows food-drug interactions with
substrate drugs of the major drug-metabolizing cytochrome P450s (i.e., CYP1A2,
CYP2C9, and CYP3A) is addressed.
METHODS: The ability of atemoya juice to inhibit the activities of phenacetin
O-deethylase (CYP1A2), diclofenac 4'-hydroxylase (CYP2C9), and midazolam
1'-hydroxylase (CYP3A) was examined in vitro using human and rat liver
microsomes. The in vivo pharmacokinetics of phenacetin and metabolites derived
from it in rats when atemoya juice or fluvoxamine (a CYP1A2 inhibitor) was
preadministered were also investigated.
RESULTS: Atemoya juice significantly inhibited CYP1A2 activity in human liver
microsomes, but not the activities of CYP2C9 and CYP3A. In spite of this
inhibition, preadministration of atemoya had no effect on the pharmacokinetics
of phenacetin, a CYP1A2 substrate, in rats. Meanwhile, preadministration of
fluvoxamine significantly extended the time needed for the elimination of
phenacetin, possibly due to the inhibition of CYP1A2. This suggests that the
intake of an excess amount of atemoya juice is necessary to cause a change in
the pharmacokinetics of phenacetin when the IC50 values for CYP1A2 inhibition by
atemoya and fluvoxamine are taken into account.
CONCLUSION: The results indicate that a daily intake of atemoya would not change
the pharmacokinetics of CYP1A2 substrates such as phenacetin as well as CYP2C9-
and CYP3A-substrate drugs. |
What is caused by gain-of-function variants in SYK? | Gain-of-function variants in SYK cause immune dysregulation and systemic inflammation in humans and mice. | |
Is Cabotegravir effective for HIV prevention? | Yes, Cabotegravir is effective for HIV prevention. | PURPOSE OF REVIEW: Preexposure prophylaxis for HIV prevention is highly
effective when taken as prescribed. Adherence to required dosing regimens for
protection may pose challenges. Long-acting agents for HIV prevention may have
the potential to improve adherence via favorable pharmacokinetics supportive of
infrequent dosing. This review focuses on the potential benefits and
considerations for the study and use of 2 long-acting injectable agents,
cabotegravir (GSK1265744LA, CAB LA) and rilpivirine (TMC278LA, RPV LA), for use
as chemoprophylaxis for HIV prevention.
RECENT FINDINGS: Oral RPV is United States Food and Drug Administration approved
for HIV treatment (in combination with other antiretrovirals). Both CAB LA and
RPV LA are currently in phase 2a safety/tolerability/pharmacokinetic studies in
anticipation and support of future efficacy evaluation. Both agents have
favorable pharmacokinetics, and use is complicated by injection site reactions.
SUMMARY: Long-acting injectable formulations, if safe and well tolerated, may
improve pharmacokinetic coverage of exposures to HIV infection. Complexities
around safety, tolerability, and starting/stopping protocols require careful
consideration. Modern antiretroviral therapy has demonstrated effectiveness in preexposure
prophylaxis (PrEP) and treatment of HIV infection. There is a demand for
prevention and treatment regimens that could overcome challenges of improving
adherence, toxicity, and dosing convenience. Cabotegravir is an integrase strand
transfer inhibitor and an analog of dolutegravir. Unlike dolutegravir,
cabotegravir has a long half-life and can be formulated into a long-acting
osuspension for parenteral administration. Initial pharmokinetic studies in
humans have demonstrated adequate drug levels with intramuscular (IM)
administration at 4 weekly and 8 weekly intervals, with few interactions with
commonly used concomitant medications. Preliminary animal PrEP studies have
shown that IM cabotegravir can prevent simian/HIV acquisition from rectal,
vaginal, and intravenous challenge. Currently, there are two ongoing Phase II
studies assessing cabotegravir as a PrEP agent in humans: ÉCLAIR and HPTN077.
Cabotegravir has been studied in combination with rilpivirine as long-acting IM
maintece therapy. The Long-Acting Antiretroviral Treatment Enabling study
demonstrated that those switching to oral cabotegravir/rilpivirine once
virologically suppressed were more likely to maintain suppression than those
continuing standard efavirenz-based therapy (82% vs 71% at 24 weeks). Initial
results of the Long-Acting Antiretroviral Treatment Enabling-2 study of
parenteral regimens found that 12 weeks after randomization to parenteral or
oral regimens, there was no difference in proportions virologically suppressed
on cabotegravir/rilpivirine daily orally vs IM every 4 weeks or 8 weeks (91% vs
94% vs 95%). The injections were well tolerated as, although they caused
injection site pain in most recipients, most participants reported satisfaction
with parenteral therapy. Cabotegravir offers a new member of the integrase
strand transfer inhibitor class with potential for alternative mode of delivery.
We await Phase III studies to define its efficacy and real-world experience to
learn which patient groups stand to benefit most from the novel mode of delivery
of treatment and PrEP. Human Immunodeficiency Virus (HIV) is a chronic infection that depletes the
immune system of essential components causing those infected to be at risk for
multiple life-threatening infections. Worldwide, millions live with this
infection, the vast majority attributable to HIV-1. Transmission persists with
hundreds of thousands of new infections reported yearly. Implementation of
combination antiretroviral therapy (cART) has been effective in improving
outcomes and decreasing transmission. Newer co-formulated agents have provided
simpler medication regimens, fewer side effects, and, in some cases, a higher
barrier to the emergence of medication resistance. Areas covered: Here, we
review trials of cabotegravir (CAB) as treatment of HIV-1 infection and its
potential use as pre-exposure prophylaxis (PrEP) in high risk individuals,
including issues around oral lead in and potential resistance emergence. Expert
opinion: CAB is efficacious when used in combination therapy orally or given
intramuscularly every 4 to 8 weeks. Its availability in a long-acting injectable
formulation (CAB-LA) makes it a valuable, novel drug to treat HIV-1 infection
when combined with long-acting injectable rilpivirine (RPV-LA). Moreover,
pre-clinical and early Phase 2a studies support its testing as monotherapy as
PrEP. Studies are underway comparing the efficacy of every 8 week CAB-LA to
tenofovir disoproxil fumarate/emtricitabine (TDF/FTC). BACKGROUND: Cabotegravir (GSK1265744) is an integrase strand transfer inhibitor
in development as a long-acting (LA) intramuscular injectable suspension for
HIV-1 pre-exposure prophylaxis (PrEP).
OBJECTIVE: We report participant outcomes from the phase IIa ECLAIR study
related to tolerability, acceptability, and satisfaction of cabotegravir LA.
METHODS: The ECLAIR study (ClinicalTrials.gov identifier, NCT02076178) was a
randomized, placebo-controlled study in healthy men not at high risk of
acquiring HIV-1. Participants were randomized (5:1) to once-daily oral
cabotegravir 30 mg or placebo tablets for 4 weeks, followed by gluteal
intramuscular injections of cabotegravir LA 800 mg or saline placebo every 12
weeks. The primary objective was to evaluate the safety of cabotegravir LA over
three injection cycles (to Week 41). Secondary objectives assessed the
tolerability, satisfaction, and acceptability of cabotegravir LA.
RESULTS: Among 115 participants who received injections in the cabotegravir
(n = 94) and placebo (n = 21) groups, 93% (n = 87) and 95% (n = 20) completed
the injection phase, respectively. Injection intolerability led to withdrawal in
4 participants (4%) receiving cabotegravir LA. The most frequently reported
Grade ≥2 adverse event was injection-site pain. Most participants (74% [n = 67])
receiving consecutive injections favored cabotegravir LA vs oral cabotegravir.
Most participants were satisfied with cabotegravir LA (75% [n = 64]), were
willing to continue (79% [n = 68]), and would recommend (87% [n = 75]) the
therapy.
CONCLUSIONS: While Grade ≥2 injection-site pain was common, most participants
reported overall satisfaction with and preference for cabotegravir LA, with few
discontinuations due to injection intolerance. These findings support
investigation of cabotegravir LA as an alternative to daily oral PrEP regimens. Cabotegravir is an investigational integrase inhibitor in development for the
treatment and pre-exposure prophylaxis of HIV-1 infection. Liver disease is a
major cause of morbidity and mortality in HIV-infected individuals and can
impact the pharmacokinetics (PK) of HIV medications. This phase 1 study
evaluated the PK of cabotegravir in individuals with moderate hepatic impairment
(n = 8) versus healthy controls (n = 8). Participants received a single oral
cabotegravir 30-mg tablet and underwent PK sampling to determine total and
unbound plasma cabotegravir concentrations. Calculated geometric least-squares
mean ratios (90% confidence intervals) for individuals with hepatic impairment
versus healthy controls were 0.73 (0.50-1.06) for AUC0-∞ , 0.69 (0.51-0.93) for
Cmax , 1.40 (0.80-2.46) for unbound concentration (CU) 2 hours postdose, 1.55
(0.82-2.94) for CU at 24 hours, 2.14 (1.57-2.90) for unbound fraction (FU) at
2 hours, and 1.90 (1.14-3.18) for FU at 24 hours. Adverse events (AEs) occurred
in 2 individuals with hepatic impairment and 3 healthy controls and were grade
1/2 in severity. No participant discontinued because of AEs. Increased FU
resulted in a modest decrease in total plasma exposure not considered clinically
relevant. We conclude that cabotegravir may be administered without dose
adjustment in patients with mild to moderate hepatic impairment. PURPOSE OF REVIEW: This review highlights the development of long-acting
injectable cabotegravir (CAB LA) for HIV preexposure prophylaxis (PrEP), with a
focus on phase 2 studies and later development.
RECENT FINDINGS: Early studies of CAB LA for HIV prevention offered promising
pharmacokinetic data and paved the way for phase 2 studies, which have now been
completed. On the basis of phase 2 data, dosing of CAB LA at 8-week intervals
consistently delivers target trough concentrations in both men and women. Recent
studies have shown no required dose adjustments for hepatic or renal disease and
minimal drug--drug interactions. Additionally, injectable PrEP is desired by
potential PrEP candidates. Still, gaps in knowledge remain with respect to
implementation and delivery, the clinical significance of the pharmacologic
tail, and dosing in key populations. Phase 3 trials are underway that are
anticipated to inform some of these questions and provide efficacy and safety
data to support regulatory submissions for CAB LA as a potential PrEP agent.
SUMMARY: Recent studies have defined an appropriate CAB LA dosing interval and
offered insight into its safety profile. Phase 3 studies will provide
much-anticipated efficacy data. If efficacious, CAB LA may provide a desirable
PrEP option for those who face challenges to daily pill adherence. A more
complete understanding of how to best integrate LA PrEP into service delivery
models will be critical for success. Bictegravir, cabotegravir, dolutegravir, elvitegravir, and raltegravir are
members of the latest class of antiretrovirals available to treat human
immunodeficiency virus (HIV) infection, the integrase strand transfer
inhibitors. Integrase strand transfer inhibitors are potent inhibitors of the
HIV integrase enzyme with IC90/95 values in the low ogram per milliliter
range and they retain antiviral activity against strains of HIV with acquired
resistance to other classes of antiretrovirals. Each of the integrase strand
transfer inhibitors have unique pharmacokinetic/pharmacodynamic properties,
influencing their role in clinical use in specific subsets of patients.
Cabotegravir, approved for use in Canada but not yet by the US Food and Drug
Administration, is formulated in both oral and intramuscular formulations; the
latter of which has shown efficacy as a long-acting extended-release
formulation. Cabotegravir, raltegravir, and dolutegravir have minimal drug-drug
interaction profiles, as their metabolism has minimal cytochrome P450
involvement. Conversely, elvitegravir metabolism occurs primarily via cytochrome
P450 3A4 and requires pharmacokinetic boosting to achieve systemic exposures
amenable to once-daily dosing. Bictegravir metabolism has similar contributions
from both cytochrome P450 3A4 and uridine 5'-diphospho-glucuronosyltransferase
1A1. Bictegravir, dolutegravir, and raltegravir are recommended components of
initial regimens for most people with HIV in the US adult and adolescent HIV
treatment guidelines. This review summarizes and compares the pharmacokinetics
and pharmacodynamics of the integrase strand transfer inhibitor agents, and
describes specific pharmacokinetic considerations for persons with hepatic
impairment, renal dysfunction, pregcy, and co-infections. Introduction: Oral pre-exposure prophylaxis (PrEP) and antiretroviral therapy
(ART) represent the cornerstones of HIV infection prevention and treatment.
However, despite their high efficacy, the need to take daily oral pill(s)
negatively impacts long-term patient adherence. In some cases, it can also be
associated with drug-drug interactions and adverse gastrointestinal effects, as
well as being a constant reminder to individuals of their HIV status. The
availability of long-acting non-orally administered antiretroviral drugs could,
therefore, be extremely useful. Cabotegravir (CAB) is a second-generation
integrase strand transfer inhibitor, characterized by a relatively high genetic
barrier and good antiretroviral potency, which is administrable as a long-acting
injectable suspension (LAI CAB).Areas covered: The authors present and discuss
the efficacy and available safety data of LAI CAB, either when co-administered
with rilpivirine (RPV; LAI CAB + RPV) for the treatment of HIV infection, or
when used as single agent for PrEP.Expert opinion: Cabotegravir has the
potential to play a primary role in the treatment and prevention of HIV
infection. The future availability of LAI CAB + RPV and LAI CAB may mark the
beginning of an era of LAI ART and PrEP, respectively. Long-acting antiretroviral implants could help protect high-risk individuals
from HIV infection. We describe the design and testing of a long-acting
reservoir subcutaneous implant capable of releasing cabotegravir for several
months. We compressed cabotegravir and excipients into cylindrical pellets and
heat-sealed them in tubing composed of hydrophilic poly(ether-urethane) -. The
implants have a 47 mm lumen length, 3.6 mm outer diameter, and 200 μm wall
thickness. Four cabotegravir pellets were sealed in the membrane, with a total
drug loading of 274 ± 3 mg. In vivo, the implants released 348 ± 107 μg/day
(median value per implant, N = 41) of cabotegravir in rhesus macaques. Five
implants generated an average cabotegravir plasma concentration of 373 ng/ml in
rhesus macaques. The non-human primates tolerated the implant without gross
pathology or microscopic signs of histopathology compared to placebo implants.
Cabotegravir plasma levels in macaques dropped below detectable levels within
two weeks after the removal of the implants. Author information:
(1)Department of Pathology, Johns Hopkins University School of Medicine,
Baltimore, Maryland, USA.
(2)Department of Medicine, Johns Hopkins University School of Medicine,
Baltimore, Maryland, USA.
(3)Instituto de Pesquisa Clinica Evandro Chagas-Fiocruz, Rio de Janeiro, Brazil.
(4)Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.
(5)FHI 360, Durham, North Carolina, USA.
(6)University of Colorado, Aurora, Colorado, USA.
(7)Monogram Biosciences, South San Francisco, California, USA.
(8)Department of Pediatrics, Johns Hopkins University School of Medicine,
Baltimore, Maryland, USA.
(9)Prevention Science Program, Division of AIDS, National Institute of Allergy
and Infectious Diseases, National Institutes of Health, Rockville, Maryland,
USA.
(10)Department of Medicine, University of California at Los Angeles, Los
Angeles, California, USA.
(11)ViiV Healthcare, Research Triangle Park, North Carolina, USA.
(12)Gilead Sciences, Foster City, California, USA.
(13)Hospital Velez Sarfield, Buenos Aires, Argentina.
(14)St Jude Children's Research Hospital, Memphis, Tennessee, USA.
(15)Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular
Medicine, University of Cape Town, Cape Town, South Africa.
(16)Institute of HIV Research and Innovation, Bangkok, Thailand.
(17)Center of Excellence in Transgender Health, Chulalongkorn University,
Bangkok, Thailand.
(18)Department of Medicine, University of North Carolina, North Carolina, USA.
(19)Center for Clinical AIDS Research & Education, University of California, Los
Angeles, Los Angeles, California, USA. Cabotegravir is a novel human immunodeficiency virus integrase enzyme inhibitor
used for prevention and treatment of HIV infection. The combinational final
dosage form, as extended release injection suspension in combination with
rilpivirine and as cabotegravir tablets (for lead-in therapy), was recently
approved in Canada, EU and in USA and is currently seeking approval also in
other countries. The subject of this investigation was to study the degradation
of cabotegravir under different stress conditions as per the International
Council for Harmonization (ICH) guidelines. The drug substance was found to be
stable in thermal, photolytic and basic stress conditions, but degraded under
acidic and oxidative stress conditions. It was determined that four main
degradation products of cabotegravir are formed in forced degradation studies.
All four main degradation products were isolated using preparative
chromatography and subjected to NMR and HRMS analysis in order to determine
their structure. We proposed degradation pathways of cabotegravir under acidic
stress conditions in solution based on the structure of isolated degradation
products, cabotegravir degradation kinetic studies and degradation studies on
two isolated key degradation products. Moreover, degradation pathway to
predomit oxidation degradation product is proposed based on the adduct of
cabotegravir and peroxide species, which was identified by LC-HRMS analysis.
This is the first report to the best of our knowledge that describes
characterized cabotegravir forced degradation impurities and provides insights
into its degradation pathways. The retrovirus HIV-1 is the etiological agent of the decades-long AIDS pandemic.
Although vaccination is the most common preexposure route to prevent acquisition
of viral disease, scalable efficacious vaccination strategies have yet to be
developed for HIV-1. By contrast, small molecule inhibitors of the HIV-1 enzymes
reverse transcriptase, integrase, and protease have been developed that
effectively block virus replication. Three different drug compounds are commonly
prescribed for people living with HIV as once-daily oral tablets. Once-daily
pills composed of two different reverse transcriptase inhibitors are moreover
approved as preexposure prophylaxis (PrEP) treatment for virus naïve individuals
who may partake in behaviors associated with increased risk of HIV-1 acquisition
such as unprotected sex or injection drug use. Long-acting (LA) injectable HIV-1
enzyme inhibitors are at the same time being developed to sidestep adherence
noncompliance issues that can arise from self-administered once-daily oral
dosing regimens. Cabotegravir (CAB)-LA, which inhibits integrase strand transfer
activity, has in recent clinical trials been shown to prevent HIV-1 acquisition
more effectively than once-daily oral dosed reverse transcriptase inhibitors. In
this Perspective, we examine bench to bedside aspects of CAB-LA treatment and
development, starting from the biochemical basis of HIV-1 integration and
pharmacological inhibition of integrase catalysis. We also review the results of
recent clinical trials that evaluated CAB-LA, as well as the promises and
challenges that surround its use for HIV/AIDS PrEP. Author information:
(1)From the Center for Clinical AIDS Research and Education, David Geffen School
of Medicine, University of California, Los Angeles (R.J.L., R.M.K.), the
Lundquist Institute at Harbor-UCLA Medical Center, Torrance (E.D.), the San
Francisco Department of Public Health, San Francisco (H.S.), and Gilead
Sciences, Foster City (J.F.R.) - all in California; the Fred Hutchinson Cancer
Research Center, Seattle (D.D., B.H., L. Cottle, M.L., Z.W.); the Louisiana
State University Health Sciences Center, New Orleans (M.E.C.); Instituto
Nacional de Infectologia Evandro Chagas-Fiocruz, Rio de Janeiro (L. Coelho,
B.G.), University of São Paulo (E.G.K.), and Centro de Referência e Treinamento
DST-AIDS-SP (J.V.M.), São Paulo, and Hospital Nossa Senhora da Conceição, Porto
Alegre (B.S.) - all in Brazil; Via Libre (R.C.), Universidad Nacional Mayor de
San Marcos (J.A.G.-C.), and Asociacion Civil Impacta Salud y Educacion (P.G.,
J.V.H.), Lima, and Asociacion Civil Selva Amazonica, Iquitos (J.C.H.) - all in
Peru; the Research Institute for Health Sciences, Chiang Mai University, Chiang
Mai (S.C.), and the Institute of HIV Research and Innovation, Bangkok (N.P.) -
both in Thailand; the Division of HIV-AIDS Prevention, Centers for Disease
Control and Prevention (E.F.D.), the School of Medicine (C.F.K., C.R.), and
Rollins School of Public Health (C.R.), Emory University - both in Atlanta; the
Perelman School of Medicine, University of Pennsylvania, Philadelphia (I.F.),
and Pennsylvania State University, State College (S.D.F.) - both in
Pennsylvania; St. Jude Children's Research Hospital, Memphis, TN (A.H.G.);
University of North Carolina at Chapel Hill, Chapel Hill (H.V.T., J.J.E.,
M.S.C.), FHI 360, Durham (A. Asmelash, M.B., C.B., J.L., N.D.S., K.G.-F., A.J.,
M.M.), and ViiV Healthcare, Research Triangle (K.Y.S., W.S., D.M., A.R.) - all
in North Carolina; Hospital General de Agudos José María Ramos Mejia (M.H.L.)
and Fundación Huésped (O.S.) - both in Buenos Aires; the Institute of Infectious
Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
(K.M.); University of Alabama at Birmingham, Birmingham (E.T.O., J.M.); Rutgers
New Jersey Medical School, Newark (S. Swaminathan); Weill Cornell Medicine, New
York (R.M.G.); Johns Hopkins University, Baltimore (P.R., P.S., E.P.-M., M.M.,
C.H., T.T.B., S.H.E., J.S.); University of Colorado Anschutz Medical Campus,
Aurora (P.A.); Massachusetts General Hospital, Boston (C.P.); University of
Miami, Coral Gables, FL (S. Safren); the Office of AIDS Research (T.H.H.) and
Division of AIDS, National Institute of Allergy and Infectious Diseases,
National Institutes of Health, Rockville, MD (K.S., A. Adeyeye). OBJECTIVE: We had previously shown that long-acting cabotegravir (CAB-LA)
injections fully protected macaques from vaginal simian HIV (SHIV) infection.
Here, we reassessed CAB-LA efficacy in the presence of depot medroxyprogesterone
acetate and multiple sexually transmitted infections (STIs) that are known to
increase HIV susceptibility in women.
DESIGN: Two macaque models of increasing vaginal STI severity were used for
efficacy assessment.
METHODS: The first study (n = 11) used a double STI model that had repeated
exposures to two vaginal STI, Chlamydia trachomatis and Trichomonas vaginalis.
Six animals were CAB-LA treated and five were controls. The second study (n = 9)
included a triple STI model with repeated exposures to C. trachomatis, T.
vaginalis and syphilis, and the contraceptive, depot medroxyprogesterone acetate
(DMPA). Six animals were CAB-LA treated and three were controls. All animals
received up to 14 vaginal SHIV challenges. A survival analysis was performed to
compare the number of SHIV challenges to infection in the drug-treated group
compared with untreated controls over time.
RESULTS: All six CAB-LA treated animals in both models, the double STI or the
triple STI-DMPA model, remained protected after 14 SHIV vaginal challenges,
while the untreated animals became SHIV-infected after a median of two
challenges (log-rank P < 0.001) or one challenge (log-rank P = 0.002),
respectively. Both models recapitulated human STI disease, with vaginal
discharge, ulcers, and seroconversion.
CONCLUSION: In these high and sustained susceptibility models spanning more than
3 months, CAB-LA maintained complete efficacy, demonstrating robustness of the
CAB-LA dose used in clinical trials, and suggesting its insensitivity to
multiple STIs and DMPA. PURPOSE OF REVIEW: Cabotegravir (CAB) and rilpivirine (RPV) is the first
long-acting injectable antiretroviral therapy (ART) option approved for
virologically suppressed adults with HIV-1. In addition, long-acting CAB is a
promising agent for HIV preexposure prophylaxis (PrEP). This review focuses on
phase 3 clinical trial results and implementation considerations for these
long-acting ART and PrEP strategies.
RECENT FINDINGS: Long-acting CAB and RPV administered every 4 weeks demonstrated
noninferiority to oral ART through week 96 in both the ATLAS and FLAIR studies,
whereas ATLAS-2M found similar efficacy through 96 weeks when the long-acting
injectable ART was administered every 8 weeks instead of every 4 weeks. For
prevention, two phase 3 trials were stopped early due to fewer incident HIV
infections in participants receiving long-acting CAB every 8 weeks compared with
daily oral tenofovir disoproxil fumarate-emtricitabine for PrEP. The long-acting
therapies were well tolerated across all clinical trials.
SUMMARY: Clinical trial results support the use of long-acting CAB for HIV PrEP
and long-acting CAB and RPV as a switch strategy for adults with HIV-1 who are
first virologically suppressed with oral ART. Implementation challenges persist,
and data are urgently needed in populations who may benefit most from
long-acting therapy, including adolescents, pregt individuals, and those with
barriers to medication adherence. |
What is the function of the protein SERT? | SERT is a Serotonin transporter. | Dynorphin (DYN) is an endogenous neurosecretory peptide which exerts its
activity by binding to the family of G protein-coupled receptors, namely the
kappa opioid receptor (KOR). Opioids are associated with pain, analgesia, and
drug abuse, which play a central role in mood disorders with monoamine
neurotransmitter interactions. Growing evidence demonstrates the cellular
signaling cascades linked to KOR-mediated monoamine transporters regulation in
cell models and native brain tissues. This chapter will review DYN/KOR role in
mood and addiction in relevance to dopaminergic and serotonergic
neurotransmissions. Also, we discuss the recent findings on KOR-mediated
differential regulation of serotonin and dopamine transporters (SERT and DAT).
These findings led to a better understanding of the role of DYN/KOR system in
aminergic neurotransmission via its modulatory effect on both amine release and
clearance. Detailed knowledge of these processes at the molecular level enables
designing novel pharmacological reagents to target transporter motifs to treat
mood and addiction and reduce unwanted side effects such as aversion, dysphoria,
sedation, and psychomimesis. RATIONALE: MDMA or Ecstasy has made a resurgence in popularity and the majority
of users consist of teenagers and adolescents. Therefore, it is important to
determine whether MDMA causes long-term damage and what this damage entails.
There is an ongoing debate about possible neurocognitive changes in
3,4-methylenedioxymethamphetamine (MDMA) users related to MDMA's neurotoxic
potential. Multiple neuroimaging studies have shown that Ecstasy use leads to
lower serotonin transporter (SERT) availability in multiple brain regions. This
may express itself in a loss of cognitive functions like memory, attention and
executive function. However, there is increasing evidence reporting that MDMA's
induced serotonergic adaptations are reversible over time. The question we thus
address is whether the recovery of SERT function predicts a recovery of
cognitive function.
OBJECTIVES: This review aims to investigate MDMA's long-term effects on SERT
availability and cognitive functioning.
METHODS: A literature search was performed in PubMed. Studies that investigated
the effects of MDMA on both SERT availability and cognitive performance were
eligible for inclusion.
RESULTS: SERT availability positively correlated with time of abstinence,
whereas memory performance did not show this correlation, but remained impaired
in MDMA users. No significant correlation between SERT availability and memory
function was found (r = 0.232, p = 0.581; r = 0.176, p = 0.677).
CONCLUSIONS: The main findings of this review are that MDMA-use leads to an
acute decrease in SERT availability and causes an impairment in cognitive
functions, mostly memory. However, SERT availability recovers with sustained
abstinence while memory function does not. This suggests that SERT availability
is not a biomarker for MDMA-induced cognitive impairment and likely also not for
MDMA-induced neurotoxicity. To explore mechanism of intestinal flora dysregulation promoting constipation,
60 specific pathogen-free (SPF) mice were used as research objects and
were treated with constipation population fecal fluid gavage and distilled water
gavage. Then, relationship between intestinal dysregulation and constipation in
mice with biofilm-mediated intestinal flora was investigated in vitro. The
results showed that recombit serotonin transporter (SERT) messenger
ribonucleic acid (mRNA) level of the constipation population fecal fluid gavage
group and the relative expression level of SERT mRNA were 1.61 ± 0.08 and 1.49 ±
0.06, which were higher markedly than those of distilled water group (P <
0.05). The level of 5-hydroxytryptamine (5-HT) in colonic tissue of the
constipation population fecal fluid gavage group was 145.36 ± 14.12 ng/mL, and
the expression level of 5-HT on the surface of epithelial cells of
biofilm-positive colonic tissue was 20.11 ± 2.03, which were significantly lower
than those of the distilled water group, with statistical significance (P <
0.05). Besides, the microbial sequencing of fecal flora indicated that The Akk
and bacteroidetes ofconstipation population fecal fluid gavage group were higher
hugely than those of distilled water group (P < 0.05).In conclusion, after the
occurrence of constipation, the diversity of intestinal microflora decreased,
and the probiotics reduced. Iintestinal microflora dysregulation would lead to
increase of SERT expression level in defecation function and intestinal motility
in mice, and the decrease of 5-HT, thereby changing the intestinal movement
resulting in mucosal protective barrier damage,thereby causing changes in
intestinal movement and the destruction of the intestinal mucosal protective
barrier, which eventually resulted in constipation. The occurrence of
constipation could be improved by regulating balance of intestinal flora,
increasing the diversity of flora, and reducing the genus of opportunistic
pathogens. |
Are G-quadruplexes(G4) possible drug targets for glioblastoma? | The 2H2-6M(4)-oxazole telomestatin derivative (6OTD) targets Glioma stem cells through G4 stabilization and promotion of DNA damage responses. Therefore, G4s are promising therapeutic targets for glioblastoma. | Guanine-rich oligonucleotides (GROs) are promising therapeutic candidate for
cancer treatment and other biomedical application. We have introduced a
G-quadruplex (G4) ligand, 3,6-bis(1-methyl-4-vinylpyridinium) carbazole
diiodide, to monitor the cellular uptake of naked GROs and map their
intracellular localizations in living cells by using confocal microscopy. The
GROs that form parallel G4 structures, such as PU22, T40214 and AS1411, are
detected mainly in the lysosome of CL1-0 lung cancer cells after incubation for
2 h. On the contrary, the GROs that form non-parallel G4 structures, such as
human telomeres (HT23) and thrombin binding aptamer (TBA), are rarely detected
in the lysosome, but found mainly in the mitochondria. Moreover, the
fluorescence resot energy transfer studies of fluorophore-labeled GROs show
that the parallel G4 structures can be retained in CL1-0 cells, whereas the
non-parallel G4 structures are likely distorted in CL1-0 cells after cellular
uptake. Of interest is that the distorted G4 structure of HT23 from the
non-parallel G4 structure can reform to a probable parallel G4 structure induced
by a G4 ligand in CL1-0 living cells. These findings are valuable to the design
and rationale behind the possible targeted drug delivery to specific cellular
organelles using GROs. Interference with telomerase and telomere maintece is emerging as an
attractive target for anticancer therapies. Ligand-induced stabilization of
G-quadruplex formation by the telomeric DNA 3'-overhang inhibits telomerase from
catalyzing telomeric DNA synthesis and from capping telomeric ends, making these
ligands good candidates for chemotherapeutic purposes. BRACO-19 is one of the
most effective and specific ligand for telomeric G4. It is shown here that
BRACO-19 suppresses proliferation and reduces telomerase activity in human
glioblastoma cells, paralleled by the displacement of telomerase from nuclear to
cytoplasm. Meanwhile, BRACO-19 triggers extensive DNA damage response at
telomere, which may result from uncapping and disassembly of telomeric T-loop
structure, characterized by the formation of anaphase bridge and telomere
fusion, as well as the release of telomere-binding protein from telomere. The
resulting dysfunctional telomere ultimately provokes p53 and p21-mediated cell
cycle arrest, apoptosis and senescence. Notably, normal primary astrocytes do
not respond to the treatment of BRACO-19, suggesting the agent's good
selectivity for cancer cells. These results reinforce the notion that
G-quadruplex binding compounds can act as broad inhibitors of telomere-related
processes and have potential as selective antineoplastic drugs for various
tumors including maligt gliomas. G-quadruplex (G4) is a higher-order nucleic acid structure that is formed by
guanine-rich sequences. G4 stabilization by small-molecule compounds called G4
ligands often causes cytotoxicity, although the potential medicinal impact of
this effect has not been fully established. Here we demonstrate that a synthetic
G4 ligand, Y2H2-6M(4)-oxazole telomestatin derivative (6OTD), limits the growth
of intractable glioblastoma (grade IV glioma) and glioma stem cells (GSCs).
Experiments involving a human cancer cell line panel and mouse xenografts
revealed that 6OTD exhibits antitumor activity against glioblastoma. 6OTD
inhibited the growth of GSCs more potently than it did the growth of
differentiated non-stem glioma cells (NSGCs). 6OTD caused DNA damage, G1 cell
cycle arrest, and apoptosis in GSCs but not in NSGCs. These DNA damage foci
tended to colocalize with telomeres, which contain repetitive G4-forming
sequences. Compared with temozolomide, a clinical DNA-alkylating agent against
glioma, 6OTD required lower concentrations to exert anti-cancer effects and
preferentially affected GSCs and telomeres. 6OTD suppressed the intracranial
growth of GSC-derived tumors in a mouse xenograft model. These observations
indicate that 6OTD targets GSCs through G4 stabilization and promotion of DNA
damage responses. Therefore, G4s are promising therapeutic targets for
glioblastoma. The G-quadruplex (G4) DNA, which has been developed as a potential anticancer
target in drug screening and design, plays a crucial role in the oncogene
transcription and translation. Tanshinone IIA derivatives with a planar
heterocycle structure may function as G4 stabilizers. We present an innovative
case of imidazole-based tanshinone IIA derivatives (1-8) especially compound 4
that improve the selectivity and the binding affinity with G4 DNA and enhance
the target tumor inhibition. Cellular and in vivo experiments indicate that the
tanshinone IIA derivative 4 inhibits the growth, metastasis, and angiogenesis of
triple-negative breast cancer cells possibly through the stabilization of
multiple G4 DNAs (e.g., c-myc, K-ras, and VEGF) to induce DNA damage. Further
investigation of the intermolecular interaction and the molecular docking
indicates that tanshinone IIA derivatives have better selective binding
capability to various G4 DNAs than to double-stranded DNA. These findings
provide guidance in modifying the molecular structures of tanshinone IIA
derivatives and reveal their potential to function as specific G4 stabilizers. |
Is RUNX1T1 associate with obesity? | Yes, the rs34269950 SNP of the RUNX1T1 gene was significantly associated with obesity risk and metabolic abnormalities. Specifically, compared to AA genotype, rs34269950 del/del genotype was associated with a 1.47 [95% confidence interval (CI): 1.01-2.14, P = 0.042] fold higher rate of obesity risk. | BACKGROUND: Runt-related transcription factor 1 (RUNX1T1) isoforms are involved
in adipogenesis. RUNX1T1 is mediated by the fat mass and obesity-associated
(FTO). However, the extent to which RUNX1T1 single-nucleotide polymorphisms
(SNPs) are associated with obesity risk or metabolic abnormalities in a
community population basis is unknown.
METHODS: Samples were obtained from the Australian Crossroads study bio-bank.
SNPs located in the coding region and 3'untranslated regions of RUNX1T1 with
minor allele frequency ≥0.05 were analysed using Taqman genotyping assays.
RESULTS: Eight candidate SNPs were genotyped successfully in 1440 participants.
Of these SNPs only rs34269950 located in the 'RRACH' motif, the most common
N6-methyladenosine (m6A) methylation modification site (recognized by FTO), was
significantly associated with obesity risk and metabolic abnormalities.
Specifically, compared to AA genotype, rs34269950 del/del genotype was
associated with a 1.47 [95% confidence interval (CI): 1.01-2.14, P = 0.042] fold
higher rate of obesity risk. Additionally, the del/del genotype was associated
with a 60% increased risk of metabolic syndrome (MetS) [odds ratio (OR) = 1.60,
95% CI: 1.10-2.32, P = 0.015], in comparison to the AA genotype. Finally,
rs34269950 del/del increased the risk of a larger waist circumference (OR =
1.65, 95% CI: 1.15-2.36, P = 0.007), but not other components of MetS.
CONCLUSION: Our study demonstrates that RUNX1T1 rs34269950, located in a
potential FTO recognition motif, is significantly associated with waist
circumference. This provides novel evidence to suggest SNPs located in RRACH
motif may be involved in RNA m6A modification and mechanistic pathways that
influence abdominal obesity. |
Is Adamts18 deficiency associated with cancer? | Yes. ADAMTS18 is a novel tumor suppressor and is critical to the pathology of human colorectal cancer. Adamts18 deficiency enhances tumorigenesis and intestinal inflammation through elevated Wnt/β-catenin and p38MAPK/ERK1/2 signaling and promotes colon cancer in this mouse model. | |
What causes Ocular Thelaziasis? | Ocular Thelaziasis is caused by Thelazia callipaeda. | Thelaziasis is an ocular infection of several mammals caused by nematodes of the
genus Thelazia (Spirurida, Thelaziidae). The adults live in the lachrymal ducts
and conjunctival sacs of infected animals, and transmission occurs by means of
different species of muscids. T. rhodesi, T. skrjabini, and T. gulosa affect
mainly cattle, inducing conjunctivitis, keratitis, and ocular discharge. This
article describes the morphological features of adult T. rhodesi, T. skrjabini,
and T. gulosa by scanning electron microscopy and highlights the most relevant
differences for their identification. Human thelaziasis is a zoonotic eye disease caused by a nematode parasite called
Thelazia. In India, seven human cases of Thelazia have been reported earlier.
This is the first case report of an infant infected with Thelazia. During the
month of July, 2012, the infant was presented with an eye problem to the eye
clinic from a village of Dibrugarh. Five worms (three female and two male) were
recovered from the left eye of the infant. Thelazia infection is rare in infant,
and report of this case is suggestive of prevalence of infection in the area and
warrants further investigation. Thelaziasis is an arthropod-born disease of the eye and adnexa caused by
Thelazia callipaeda, a nematode parasite transmitted by drosophilid flies to
carnivores and humans. Because of its distribution mainly confined to South
Asian countries and Russia, it is commonly known as Oriental eye worm. It is
often under-reported and not been given its due clinical importance. We report
first case of human thelaziasis from Hassan District, Karnataka. Five
creamy-white, translucent worms were removed from the conjunctival sac of a
74-year-old male patient. Based on morphological characters, the worms were
identified as nematodes belonging to the genus Thelazia and speciation was
confirmed by CDC, Atlanta as callipaeda. Rarity of the disease and its ability
to cause both extra and intraocular manifestations leading to ocular morbidity
is the reason for presenting this case. From the available data, this is the
first case report from Karnataka, India. BACKGROUND: Thelazia callipaeda is the main causative organism in thelaziasis,
commonly infecting orbital cavities and associated tissues of carnivores.
Thelazia callipaeda infection is rarely reported in humans, especially in
infants.
CASE PRESENTATION: A 5-month-old male infant presented with 2 weeks of redness
and increased secretions in the left eye. On examination, the left eye revealed
the presence of one creamy thread-like mobile worm in the conjunctival sac.
During surgical exploration, a total of 11 worms were extracted from the left
eye. The worms were morphologically identified as seven female and four male T.
callipaeda. Ocular symptoms resolved rapidly after the removal of the worms,
with no recurrence after the 6-month follow-up.
CONCLUSION: We present here detailed clinical and morphological information
pertaining to T. callipaeda infection, which is considered to be a probably
neglected parasitic disease of the eye. This case illustrates the importance of
including thelaziasis into the differential diagnosis of ocular surface
diseases, especially in infant patients. Thelaziasis is an ocular arthropod-borne, zoonotic disease of the eye infecting
the conjunctival sac, lacrimal duct, and lacrimal gland caused by a nematode of
the genus Thelazia. We report the first case of human ocular thelaziasis in
Nepal in a 6-month-old child from a Rukum district, Nepal. The infant presented
with conjunctivitis, and his visual acuity and dilated fundal examination were
normal. A total of 6 worms were removed for identification. Collected nematodes
were identified based on morphological keys as Thelazia callipaeda. The
patient's symptoms improved after removal of the nematodes. An 80-year-old male reported to the clinic with complaints of diminished vision,
foreign body sensation, and occasionally some black object moving in front of
the right eye. Detailed ocular examination revealed three slender creamy white
live worms in the conjunctival sac of the right eye. Total three worms were
retrieved and sent to the pathology department for detailed examination. The
worm was identified as gravid Thelazia callipaeda. As per the search results in
PubMed and Cochrane search engine, this is the first report of human case of
gravid Thelazia infestation with simultaneous existence of embryonated or
ensheathed eggs and primary-stage larvae in the same worm. |
What is the role of cytidine deaminase in healthy cells? | Activation-induced cytidine deaminase (AID) catalyses the deamination of deoxycytidines to deoxyuracils within immunoglobulin genes to induce somatic hypermutation and class-switch recombination. | The human genome contains 11 APOBEC (apolipoprotein B mRNA editing catalytic
polypeptide-like) cytidine deaminases classified into four families. These
proteins function mainly in innate antiviral immunity and can also restrict
endogenous retrotransposable element multiplication. The present study focuses
on APOBEC3C (A3C), a member of the APOBEC3 subfamily. Some APOBEC3 proteins use
their enzymatic activity on genomic DNA, inducing mutations and DNA damage,
while other members facilitate DNA repair. Our results show that A3C is highly
expressed in cells treated with DNA-damaging agents. Its expression is regulated
by p53. Depletion of A3C slightly decreases proliferation and does not affect
DNA repair via homologous recombination or nonhomologous end joining. The A3C
interactomes obtained from control cells and cells exposed to the genotoxin
etoposide indicated that A3C is a nucleolar protein. This was confirmed by the
detection of either endogenous or ectopic A3C in nucleoli. Interestingly, we
show that A3C is excluded from areas of DNA breaks in live cells. Our data also
indicate that the C-terminal part of A3C is responsible for its nucleolar
localization and exclusion from DNA damage sites. Activation-induced cytidine deaminase (AID) catalyses the deamination of
deoxycytidines to deoxyuracils within immunoglobulin genes to induce somatic
hypermutation and class-switch recombination1,2. AID-generated deoxyuracils are
recognized and processed by subverted base-excision and mismatch repair pathways
that ensure a mutagenic outcome in B cells3-6. However, why these DNA repair
pathways do not accurately repair AID-induced lesions remains unknown. Here,
using a genome-wide CRISPR screen, we show that FAM72A is a major determit
for the error-prone processing of deoxyuracils. Fam72a-deficient CH12F3-2 B
cells and primary B cells from Fam72a-/- mice exhibit reduced class-switch
recombination and somatic hypermutation frequencies at immunoglobulin and Bcl6
genes, and reduced genome-wide deoxyuracils. The somatic hypermutation spectrum
in B cells from Fam72a-/- mice is opposite to that observed in mice deficient in
uracil DNA glycosylase 2 (UNG2)7, which suggests that UNG2 is hyperactive in
FAM72A-deficient cells. Indeed, FAM72A binds to UNG2, resulting in reduced
levels of UNG2 protein in the G1 phase of the cell cycle, coinciding with peak
AID activity. FAM72A therefore causes U·G mispairs to persist into S phase,
leading to error-prone processing by mismatch repair. By disabling the DNA
repair pathways that normally efficiently remove deoxyuracils from DNA, FAM72A
enables AID to exert its full effects on antibody maturation. This work has
implications in cancer, as the overexpression of FAM72A that is observed in many
cancers8 could promote mutagenesis. Efficient humoral responses rely on DNA damage, mutagenesis and error-prone DNA
repair. Diversification of B cell receptors through somatic hypermutation and
class-switch recombination are initiated by cytidine deamination in DNA mediated
by activation-induced cytidine deaminase (AID)1 and by the subsequent excision
of the resulting uracils by uracil DNA glycosylase (UNG) and by mismatch repair
proteins1-3. Although uracils arising in DNA are accurately repaired1-4, how
these pathways are co-opted to generate mutations and double-strand DNA breaks
in the context of somatic hypermutation and class-switch recombination is
unknown1-3. Here we performed a genome-wide CRISPR-Cas9 knockout screen for
genes involved in class-switch recombination and identified FAM72A, a protein
that interacts with the nuclear isoform of UNG (UNG2)5 and is overexpressed in
several cancers5. We show that the FAM72A-UNG2 interaction controls the levels
of UNG2 and that class-switch recombination is defective in Fam72a-/- B cells
due to the upregulation of UNG2. Moreover, we show that somatic hypermutation is
reduced in Fam72a-/- B cells and that its pattern is skewed upon upregulation of
UNG2. Our results are consistent with a model in which FAM72A interacts with
UNG2 to control its physiological level by triggering its degradation,
regulating the level of uracil excision and thus the balance between error-prone
and error-free DNA repair. Our findings have potential implications for
tumorigenesis, as reduced levels of UNG2 mediated by overexpression of Fam72a
would shift the balance towards mutagenic DNA repair, rendering cells more prone
to acquire mutations. |
Summarize the cause of autosomal dominant Spinocerebellar Ataxia type 3. | Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is a progressive autosomal dominant neurodegenerative disease caused by abnormal CAG repeats in the exon 10 of ATXN3. | Spinocerebellar ataxia type 1 and type 3 (SCA1, SCA3) are autosomal domit
neurodegenerative disorders caused by expanded CAG trinucleotide repeats in
novel genes. In our collective of SCA1 and SCA3 families, we observed distortion
of the Mendelian 1:1 segregation of the disease. The mutated alleles were
preferentially transmitted by female carriers in SCA3, whereas a gender effect
on clinical features such as age of onset was not obvious. The mechanism
underlying segregation distortion remains to be established. Spinocerebellar ataxia type 1 (SCA1), spinocerebellar ataxia type 2 (SCA2) and
Machado-Joseph disease or spinocerebellar ataxia type 3 (MJD/SCA3) are three
distinctive forms of autosomal domit spinocerebellar ataxia (SCA) caused by
expansions of an unstable CAG repeat localized in the coding region of the
causative genes. Another related disease, dentatorubropallidoluysian atrophy
(DRPLA) is also caused by an unstable triplet repeat and can present as SCA in
late onset patients. We investigated the frequency of the SCA1, SCA2, MJD/SCA3
and DRPLA mutations in 328 Brazilian patients with SCA, belonging to 90
unrelated families with various patterns of inheritance and originating in
different geographic regions of Brazil. We found mutations in 35 families (39%),
32 of them with a clear autosomal domit inheritance. The frequency of the
SCA1 mutation was 3% of all patients; and 6% in the domitly inherited SCAs.
We identified the SCA2 mutation in 6% of all families and in 9% of the families
with autosomal domit inheritance. The MJD/SCA3 mutation was detected in 30%
of all patients; and in the 44% of the domitly inherited cases. We found no
DRPLA mutation. In addition, we observed variability in the frequency of the
different mutations according to geographic origin of the patients, which is
probably related to the distinct colonization of different parts of Brazil.
These results suggest that SCA may be occasionally caused by the SCA1 and SCA2
mutations in the Brazilian population, and that the MJD/SCA3 mutation is the
most common cause of domitly inherited SCA in Brazil. Machado-Joseph disease (MJD, also known as spinocerebellar ataxia type 3, SCA3),
an autosomal domit neurological disorder, is caused by an abnormal expanded
polyglutamine (polyQ) repeat in the ataxin-3 protein. The length of the expanded
polyQ stretch correlates positively with the severity of the disease and
inversely with the age at onset. To date, we cannot fully explain the mechanism
underlying neurobiological abnormalities of this disease. Yet, accumulating
reports have demonstrated the functions of ataxin-3 protein in the chaperone
system, ubiquitin-proteasome system, and aggregation-autophagy, all of which
suggest a role of ataxin-3 in the clearance of misfolded proteins. Notably, the
SCA3 pathogenic form of ataxin-3 (ataxin-3(exp)) impairs the misfolded protein
clearance via mechanisms that are either dependent or independent of its
deubiquitinase (DUB) activity, resulting in the accumulation of misfolded
proteins and the progressive loss of neurons in SCA3. Some drugs, which have
been used as activators/inducers in the chaperone system, ubiquitin-proteasome
system, and aggregation-autophagy, have been demonstrated to be efficacious in
the relief of neurodegeneration diseases like Huntington's disease (HD),
Parkinson's (PD), Alzheimer's (AD) as well as SCA3 in animal models and clinical
trials, putting misfolded protein clearance on the list of potential therapeutic
targets. Here, we undertake a comprehensive review of the progress in
understanding the physiological functions of ataxin-3 in misfolded protein
clearance and how the polyQ expansion impairs misfolded protein clearance. We
then detail the preclinical studies targeting the elimination of misfolded
proteins for SCA3 treatment. We close with future considerations for translating
these pre-clinical results into therapies for SCA3 patients. Author information:
(1)Department of Neurology, The First Affiliated Hospital of Zhengzhou
University, Zhengzhou 450052, China.
(2)Zhengzhou University, Zhengzhou, He 450001, China.
(3)School of life sciences, Zhengzhou University, Zhengzhou, He 450001,
China.
(4)Center for Stem Cell and Regenerative Medicine, Department of Basic Medical
Sciences, The First Affiliated Hospital, College of Medicine, Zhejiang
University, Hangzhou, Zhejiang 310058, China; Institute of Hematology, Zhejiang
University, Hangzhou, Zhejiang 310058, China.
(5)Department of Neurology, The First Affiliated Hospital of Zhengzhou
University, Zhengzhou 450052, China. Electronic address: [email protected].
(6)Department of Neurology, The First Affiliated Hospital of Zhengzhou
University, Zhengzhou 450052, China. Electronic address: [email protected]. BACKGROUND: Spinocerebellar ataxias (SCAs) are rare domitly inherited
neurodegenerative disorders that lead to severe disability and premature death.
OBJECTIVE: To better characterize the natural history of the most common SCAs,
SCA1, SCA2, SCA3 and SCA6, we performed a meta-analysis of literature to
determine disease progression, provide data for sample-sizes calculations for
interventional trials and study the impact of geographical locations and study
follow-up on disease progression.
METHODS: A systematic literature search from MEDLINE and EMBASE databases for
longitudinal natural history studies of SCA patients was conducted. Studies
using the Scale for the Assessment and Rating Ataxia (SARA) as outcome measure
were considered. Random-effect (RE) meta-analysis was applied to estimate pooled
disease progression.
RESULTS: Six studies with 1215 SCA patients enrolled between 2005 and 2016 were
finally selected. Annual pooled SARA score increase was 1.83 (1.46-2.20) in
patients with SCA1, 1.40 (1.19-1.61) in patients with SCA2, 1.41 (0.97-1.84) in
patients with SCA3, and 0.81 (0.66-0.97) in patients with SCA6. For patients
with SCA3, disease progression was faster in studies located in Asia and Europe
than in the US. Two-arm interventional trials of 1-year duration to achieve 80%
power and α level of 5% would require 92 patients per group with SCA1, 97 with
SCA2, 115 with SCA3, and 430 with SCA6 to detect a 50% reduction in disease
progression.
CONCLUSION: This meta-analysis provides quantitative data on the progression of
the most common spinocerebellar ataxias based on patient numbers that exceed
those of previous studies and confirms that disease progression is faster in
SCA1, intermediate in SCA2 and SCA3 and slower in SCA6, with similar rates of
disease progression in SCA2 and SCA3 between different populations, suggesting a
possibility of international collaborative studies. Nevertheless,
individual-patient data meta-analysis is needed to better understand the risk
factors that influence disease progression and improve patient stratification in
interventional trials. Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is a domit
neurodegenerative disease caused by the expansion of a CAG repeat tract in
ATXN3. Anticipation and worsening of clinical picture in subsequent generations
were repeatedly reported, but there is no indication that SCA3/MJD frequency is
changing. Thus, we performed a systematic review and meta-analysis on phenomena
with potential effect on SCA3/MJD recurrency in populations: instability of CAG
repeat transmissions, anticipation, fitness, and segregation of alleles.
Transmission of the mutant allele was associated with an increase of 1.23 CAG
repeats in the next generation, and the average change in age at onset showed an
anticipation of 7.75 years per generation; but biased recruitments cannot be
ruled out. Affected SCA3/MJD individuals had 45% more children than related
controls. Transmissions from SCA3/MJD carriers showed that the expanded allele
was segregated in 64% of their children. In contrast, transmissions from normal
subjects showed that the minor allele was segregated in 54%. The present
meta-analysis concluded that there is a segregation distortion favoring the
expanded allele, among children of carriers. Therefore, further studies on
transmissions and anticipation phenomena as well as more observations about
fertility are required to clarify these selective forces over SCA3/MJD. Spinocerebellar Ataxia (SCA) is a heterogeneous adult-onset disorder with an
autosomal domit inheritance pattern mainly caused by triplet repeat
expansions. Clinical diagnosis of SCA is based on phenotypic features followed
by confirmation through molecular diagnosis. To identify status of repeat range
in Indian SCA cases and provide extended family screening, we enrolled 70
clinical SCA suspects. For molecular diagnosis, multiplex PCR (M-PCR) was used
for common Indian SCA subtypes 1, 2, 3, 6, 7, 10, 12 and 17. TP-PCR was further
used in SCA2, 7 and 10 to identify larger expansions. Eighteen out of 70 SCA
suspects (25%) were found to be positive for various SCA subtypes- (5 SCA1
(28%), 6 SAC2 (34%), 2 SCA3 (12%), 3 SCA7 (16%) and one each for SCA6 (1%) and
SCA17 (1%) subtypes). Genetic counselling and extended family screening were
offered to all positive cases and yielded additional nine cases. We have
established M-PCR and TP-PCR to detect the CAG repeat expansion in SCA suspects.
This method can confirm SCA subtypes in a reliable, rapid and cost-effective
way. Genetic characterization of SCA-related genes has great clinical relevance,
as it could provide additional information and guidance to clinicians and family
members regarding prognosis. Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is a progressive
autosomal domit neurodegenerative disease caused by abnormal CAG repeats in
the exon 10 of ATXN3. The accumulation of the mutant ataxin-3 proteins carrying
expanded polyglutamine (polyQ) leads to selective degeneration of neurons. Since
the pathogenesis of SCA3 has not been fully elucidated, and no effective
therapies have been identified, it is crucial to investigate the pathogenesis
and seek new therapeutic strategies of SCA3. Induced pluripotent stem cells
(iPSCs) can be used as the ideal cell model for the molecular pathogenesis of
polyQ diseases. Abnormal CAG expansions mediated by CRISPR/Cas9 genome
engineering technologies have shown promising potential for the treatment of
polyQ diseases, including SCA3. In this study, SCA3-iPSCs can be corrected by
the replacement of the abnormal CAG expansions (74 CAG) with normal repeats (17
CAG) using CRISPR/Cas9-mediated homologous recombination (HR) strategy. Besides,
corrected SCA3-iPSCs retained pluripotent and normal karyotype, which can be
differentiated into a neural stem cell (NSCs) and neuronal cells, and maintained
electrophysiological characteristics. The expression of differentiation markers
and electrophysiological characteristics were similar among the neuronal
differentiation from normal control iPSCs (Ctrl-iPSCs), SCA3-iPSCs, and isogenic
control SCA3-iPSCs. Furthermore, this study proved that the phenotypic
abnormalities in SCA3 neurons, including aggregated IC2-polyQ protein, decreased
mitochondrial membrane potential (MMP) and glutathione expressions, increased
reactive oxygen species (ROS), intracellular Ca2+ concentrations, and lipid
peroxidase malondialdehyde (MDA) levels, all were rescued in the corrected
SCA3-NCs. For the first time, this study demonstrated the feasibility of
CRISPR/Cas9-mediated HR strategy to precisely repair SCA3-iPSCs, and reverse the
corresponding abnormal disease phenotypes. In addition, the importance of
genetic control using CRISPR/Cas9-mediated iPSCs for disease modeling. Our work
may contribute to providing a potential ideal model for molecular mechanism
research and autologous stem cell therapy of SCA3 or other polyQ diseases, and
offer a good gene therapy strategy for future treatment. |
Through which pathway does the FTO-guided demethylation of GADD46 drive myogenesis? | FTO-mediated demethylation of GADD45B promotes myogenesis through the activation of p38 MAPK pathway. | N6-methyladenosine (m6A) modification plays a critical role in mammalian
development. However, the role of m6A in the skeletal muscle development remains
largely unknown. Here, we report a global m6A modification pattern of goat
skeletal muscle at two key development stages and identified that the m6A
modification regulated the expression of the growth arrest and DNA
damage-inducible 45B (GADD45B) gene, which is involved in myogenic
differentiation. We showed that GADD45B expression increased during myoblast
differentiation, whereas the downregulation of GADD45B inhibits myogenic
differentiation and mitochondrial biogenesis. Moreover, the expression of
GADD45B regulates the expression of myogenic regulatory factors and peroxisome
proliferator-activated receptor gamma coactivator 1 alpha by activating the p38
mitogen-activated protein kinase (MAPK) pathway. Conversely, the inactivation of
p38 MAPK abolished the GADD45B-mediated myogenic differentiation. Furthermore,
we found that the knockdown of fat mass and obesity-associated protein (FTO)
increases GADD45B m6A modification and decreases the stability of GADD45B mRNA,
which impairs myogenic differentiation. Our results indicate that the
FTO-mediated m6A modification in GADD45B mRNA drives skeletal muscle
differentiation by activating the p38 MAPK pathway, which provides a molecular
mechanism for the regulation of myogenesis via RNA methylation. |
What are the key characteristics of the syndrome caused by ANKRD17 loss-of-function variants? | Heterozygous ANKRD17 loss-of-function variants cause a syndrome with intellectual disability, speech delay, and dysmorphia. | |
Is Ozanimod effective for Ulcerative Colitis? | Yes, Ozanimod is effective for Ulcerative Colitis. | The sphingosine-1-phosphate receptor-1 (S1P1) agonist ozanimod ameliorates
ulcerative colitis, yet its mechanism of action is unknown. Here, we examine the
cell subsets that express S1P1 in intestine using S1P1-eGFP mice, the regulation
of S1P1 expression in lymphocytes after administration of dextran sulfate sodium
(DSS), after colitis induced by transfer of CD4+CD45RBhi cells, and by crossing
a mouse with TNF-driven ileitis with S1P1-eGFP mice. We then assayed the
expression of enzymes that regulate intestinal S1P levels, and the effect of
FTY720 on lymphocyte behavior and S1P1 expression. We found that not only T and
B cells express S1P1, but also dendritic (DC) and endothelial cells.
Furthermore, chronic but not acute inflammatory signals increased S1P1
expression, while the enzymes that control tissue S1P levels in mice and humans
with inflammatory bowel disease (IBD) were uniformly dysregulated, favoring
synthesis over degradation. Finally, we observed that FTY720 reduced T-cell
velocity and induced S1P1 degradation and retention of Naïve but not effector T
cells. Our data demonstrate that chronic inflammation modulates S1P1 expression
and tissue S1P levels and suggests that the anti-inflammatory properties of S1PR
agonists might not be solely due to their lymphopenic effects, but also due to
potential effects on DC migration and vascular barrier function. BACKGROUND: Ozanimod (RPC1063) is an oral agonist of the sphingosine-1-phosphate
receptor subtypes 1 and 5 that induces peripheral lymphocyte sequestration,
potentially decreasing the number of activated lymphocytes circulating to the
gastrointestinal tract.
METHODS: We conducted a double-blind, placebo-controlled phase 2 trial of
ozanimod in 197 adults with moderate-to-severe ulcerative colitis. Patients were
randomly assigned, in a 1:1:1 ratio, to receive ozanimod at a dose of 0.5 mg or
1 mg or placebo daily for up to 32 weeks. The Mayo Clinic score was used to
measure disease activity on a scale from 0 to 12, with higher scores indicating
more severe disease; subscores range from 0 to 3, with higher scores indicating
more severe disease. The primary outcome was clinical remission (Mayo Clinic
score ≤2, with no subscore >1) at 8 weeks.
RESULTS: The primary outcome occurred in 16% of the patients who received 1 mg
of ozanimod and in 14% of those who received 0.5 mg of ozanimod, as compared
with 6% of those who received placebo (P=0.048 and P=0.14, respectively, for the
comparison of the two doses of ozanimod with placebo). Differences in the
primary outcome between the group that received 0.5 mg of ozanimod and the
placebo group were not significant; therefore, the hierarchical testing plan
deemed the analyses of secondary outcomes exploratory. Clinical response
(decrease in Mayo Clinic score of ≥3 points and ≥30% and decrease in
rectal-bleeding subscore of ≥1 point or a subscore ≤1) at 8 weeks occurred in
57% of those receiving 1 mg of ozanimod and 54% of those receiving 0.5 mg, as
compared with 37% of those receiving placebo. At week 32, the rate of clinical
remission was 21% in the group that received 1 mg of ozanimod, 26% in the group
that received 0.5 mg of ozanimod, and 6% in the group that received placebo; the
rate of clinical response was 51%, 35%, and 20%, respectively. At week 8,
absolute lymphocyte counts declined 49% from baseline in the group that received
1 mg of ozanimod and 32% from baseline in the group that received 0.5 mg. The
most common adverse events overall were anemia and headache.
CONCLUSIONS: In this preliminary trial, ozanimod at a daily dose of 1 mg
resulted in a slightly higher rate of clinical remission of ulcerative colitis
than placebo. The trial was not large enough or of sufficiently long duration to
establish clinical efficacy or assess safety. (Funded by Receptos; TOUCHSTONE
ClinicalTrials.gov number, NCT01647516.). Crohns disease (CD) and ulcerative colitis (UC) belong to chronic inflammatory
bowel diseases, which are induced by autoimmune processes. While CD is
characterized by over-activity of Th1, ILC1, and MAIT cells, UC is mediated by
exaggerated activities of Th2 and ILC2 cells and cytokines they produce.
Knowledge of the pathogenesis enabled a rational therapy based mostly on
biologics and small molecules. TNF is the principal proinflammatory cytokine in
both diseases. Anti-TNF monoclonal antibodies, mostly infliximab or adalimumab
were therefore introduced to their treatment. Approximately 50-70 % of CD and
more than 33 % of UC patients respond to primary treatment only, which resulted
in the development of other biologics and small molecules. Out of them,
monoclonal antibodies targeting adhesive molecules (vedolizumab, etrolizumab)
and p40 chains shared by IL12 and IL23 (ustekinumab) have been already in
clinical practice. There are also other small molecules in clinical trials:
mongersen, tafacitinib, and ozanimod. Mongersen supports immunosuppressive
activity of TGFβ; it has been tried for the treatment of CD. Tofacitinib
inhibits activity of JAK kinases; it was shown to be effective in UC management.
Ozanimod interferes with migrations of activated T cells to the site of
inflammation and is a promising drug for the UC treatment.Key words: Crohns
disease - mongersen - monoclonal antibodies - ozanimod - tofacitinib -
ulcerative colitis. BACKGROUND AND AIMS: This analysis examined the long-term safety and efficacy of
ozanimod in patients with moderately to severely active ulcerative colitis [UC]
with ≥ 4 years of follow-up in the phase 2 TOUCHSTONE open-label extension
[OLE].
METHODS: Patients receiving placebo or ozanimod HCl 0.5 mg or 1 mg during the
double-blind period could enter the OLE [ozanimod HCl 1 mg daily]. Partial Mayo
score [pMS] clinical response and remission were assessed through OLE week 200
and summarized descriptively using observed cases [OC] and non-responder
imputation [NRI]. Endoscopy was required at OLE week 56 and the end of
treatment. Parameters associated with endoscopy were summarized at weeks 56 and
104 [OC], and week 56 [NRI]. C-reactive protein and faecal calprotectin were
assessed. Adverse events were monitored throughout the study.
RESULTS: Of 197 patients receiving double-blind treatment, 170 entered the OLE.
Discontinuation rates were 28% at year 1 and 15-18% annually through year 4.
Partial Mayo measures indicated clinical response and remission rates at OLE
week 200 of 93.3% and 82.7%, respectively, using OC and 41% and 37% with the
more conservative NRI analysis. At weeks 56 and 104, respectively, histological
remission rates were 46.3% and 38.5%, and endoscopic improvement rates were
46.4% and 46.5% [OC]. No new safety signals were identified during ≥ 4 years of
follow-up.
CONCLUSIONS: There was a high rate of continued study participation and
long-term benefit with ozanimod HCl 1 mg daily based on clinical, histological
and biomarker measures in patients with moderately to severely active UC in the
TOUCHSTONE OLE. [NCT02531126]. OBJECTIVE: To review the pharmacological and clinical profile of ozanimod in the
treatment of ulcerative colitis (UC).
DATA SOURCES: A PubMed search was conducted from inception to July 2021 using
the keywords ozanimod, ulcerative colitis, and sphingosine 1-phosphate receptor
modulator. Information was also extracted from published abstracts and the
package insert.
STUDY SELECTION AND DATA EXTRACTION: Phase 2 and 3 studies and relevant
literature on ozanimod pharmacological and clinical profiles were reviewed.
DATA SYNTHESIS: Ozanimod approval was based on True North, a phase 3 trial
evaluating ozanimod's efficacy and safety in the treatment of moderate to severe
UC. Compared with placebo, ozanimod led to clinical remission in a significantly
higher proportion of patients in both the induction and maintece phase.
Additionally, for secondary end points of clinical response, endoscopic
improvement, corticosteroid-free remission, and mucosal healing, ozanimod
performed significantly better than placebo. Common adverse events included
infections, headaches, hypertension, bradycardia, and liver enzyme elevations.
RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: Ozanimod is the first
sphingosine 1-phosphate modulator to be approved for UC and is administered
orally. Its efficacy profile is comparable with other UC medications. However,
its safety profile is unique, requiring extensive assessments prior to
initiation of and during treatment. Thus, it is unclear how ozanimod will be
positioned in UC treatment.
CONCLUSION: Ozanimod is another option in the growing arsenal of UC treatment.
Although it offers a novel mechanism of action and is administered orally, there
are important safety, dosing, and pharmacokinetic factors to consider prior to
initiation and use. |
What is the function of the protein PIEZO1? | Piezo1 is a key element of the mechanotransduction process and can transduce mechanical signals into biological signals by mediating Ca2+ influx, which in turn regulates cytoskeletal remodeling and stress alterations. | Mechanosensitive channels are integral membrane proteins that sense mechanical
stimuli. Like most plasma membrane ion channel proteins they must pass through
biosynthetic quality control in the endoplasmic reticulum that results in them
reaching their destination at the plasma membrane. Here we show that N-linked
glycosylation of two highly conserved asparagine residues in the 'cap' region of
mechanosensitive Piezo1 channels are necessary for the mature protein to reach
the plasma membrane. Both mutation of these asparagines (N2294Q/N2331Q) and
treatment with an enzyme that hydrolyses N-linked oligosaccharides (PNGaseF)
eliminates the fully glycosylated mature Piezo1 protein. The N-glycans in the
cap are a pre-requisite for N-glycosylation in the 'propeller' regions, which
are present in loops that are essential for mechanotransduction. Importantly,
trafficking-defective Piezo1 variants linked to generalized lymphatic dysplasia
and bicuspid aortic valve display reduced fully N-glycosylated Piezo1 protein.
Thus the N-linked glycosylation status in vitro correlates with efficient
membrane trafficking and will aid in determining the functional impact of Piezo1
variants of unknown significance. BACKGROUND: Mechanical ventilation can induce or aggravate lung injury, which is
termed ventilator-induced lung injury (VILI). Piezo1 is a key element of the
mechanotransduction process and can transduce mechanical signals into biological
signals by mediating Ca2+ influx, which in turn regulates cytoskeletal
remodeling and stress alterations. We hypothesized that it plays an important
role in the occurrence of VILI, and investigated the underlying mechanisms.
METHODS: High tidal volume mechanical ventilation and high magnitude cyclic
stretch were performed on Sprague-Dawley rats, and A549 and human pulmonary
microvascular endothelial cells, respectively, to establish VILI models.
Immunohistochemical staining, flow cytometry, histological examination,
enzyme-linked immunosorbent assay, western blotting, quantitative real-time
polymerase chain reaction and survival curves were used to assess the effect of
Piezo1 on induction of lung injury, as well as the signaling pathways involved.
RESULTS: We observed that Piezo1 expression increased in the lungs after high
tidal volume mechanical ventilation and in cyclic stretch-treated cells.
Mechanistically, we observed the enhanced expression of RhoA/ROCK1 in both
cyclic stretch and Yoda1-treated cells, while the deficiency or inhibition of
Piezo1 dramatically antagonized RhoA/ROCK1 expression. Furthermore, blockade of
RhoA/ROCK1 signaling using an inhibitor did not affect Piezo1 expression. GSMTx4
was used to inhibit Piezo1, which alleviated VILI-induced pathologic changes,
water content and protein leakage in the lungs, and the induction of systemic
inflammatory mediators, and improved the 7-day mortality rate in the model rats.
CONCLUSIONS: These findings indicate that Piezo1 affects the development and
progression of VILI through promotion of RhoA/ROCK1 signaling. BACKGROUND: To explore the role of the mechanosensitive ion channel Piezo1 in
the proliferation and osteogenic differentiation of human dental follicle cells
(hDFCs), and its mechanism, so as to provide the basis for the use of hDFCs to
achieve bone regeneration.
METHODS: hDFCs were obtained from fresh dental follicle tissues by enzymatic
digestion, and cell phenotype and multipotential differentiation were
identified. Identification of the expression of mechanosensitive ion channel
Piezo1 was performed by immunofluorescence and immunohistochemistry. CCK-8 was
used to determine the optimal concentration of the Piezo1 agonist, Yoda1. Then,
according to the obtained results, Alizarin red staining, RT-PCR quantitative
analysis and Western blot were used to further observe the osteogenic
differentiation of hDFCs and its probable mechanism via Wnt/β-catenin
signalling. The data were analysed by SPSS 22.0 software.
RESULTS: The results of the concentration gradient experiments indicated that
0.5 µM Piezo1 agonist (Yoda1) enhanced the proliferation of hDFCs. Compared with
the control group, a considerable number of calcium nodules showed that
activating Piezo1 could promote the osteogenic differentiation of hDFCs. The
relative mRNA and protein expression of Piezo1, ALP, RUNX2, OCN and BMP2 in the
Piezo1 agonist group were higher than that of the control group. Furthermore,
the expression of Wnt3a and β-catenin related to the classical osteogenic
pathway were significantly up-regulated in the Piezo1 agonist group.
CONCLUSION: Activating mechanosensitive ion channel Piezo1 with an appropriate
concentration of Yoda1 has a positive effect on the proliferation and osteogenic
differentiation of hDFCs. This mechanism of promoting osteogenic differentiation
may be mediated by the Wnt/β-catenin pathway. 1. |
Please list 3 biologic(monoclonal antibody) drugs used to treat migraine headaches. | Large molecule biologic antibody (mAb) approaches that are given subcutaneously to neutralize circulating CGRP peptide (fremanezumab, galcanezumab) or block CGRP receptors (erenumab) have shown consistent efficacy and tolerability in multicenter migraine prevention trials and are now approved for clinical use. | BACKGROUND: Calcitonin gene-related peptide (CGRP) is a validated target for the
treatment of episodic migraine. Here we assess the safety, tolerability, and
efficacy of TEV-48125, a monoclonal anti-CGRP antibody, in the preventive
treatment of high-frequency episodic migraine.
METHODS: In this multicentre, randomised, double-blind, placebo-controlled,
phase 2b study, we enrolled men and women (aged 18-65 years) from 62 sites in
the USA who had migraine headaches 8-14 days per month. Using a randomisation
list generated by a central computerised system and an interactive web response
system, we randomly assigned patients (1:1:1; stratified by sex and use of
concomitant preventive drugs) after a 28 day run-in period to three 28 day
treatment cycles of subcutaneous 225 mg TEV-48125, 675 mg TEV-48125, or placebo.
Investigators, patients, and the funder were blinded to treatment allocation.
Patients reported headache information daily using an electronic diary. Primary
endpoints were change from baseline in migraine days during the third treatment
cycle (weeks 9-12) and safety and tolerability. The secondary endpoint was
change relative to baseline in headache-days during weeks 9-12. Efficacy
endpoints were analysed for the intention-to-treat population. Safety and
tolerability were analysed using descriptive statistics. This trial is
registered at ClinicalTrials.gov, number NCT02025556.
FINDINGS: Between Jan 8, 2014, and Oct 15, 2014, we enrolled 297 participants:
104 were randomly assigned to receive placebo, 95 to receive 225 mg TEV-48125,
and 96 to receive 675 mg TEV-48125. The least square mean (LSM) change in number
of migraine-days from baseline to weeks 9-12 was -3.46 days (SD 5.40) in the
placebo group, -6.27 days (5.38) in the 225 mg dose group, and -6.09 days (5.22)
in the 675 mg dose group. The LSM difference in the reduction of migraine-days
between the placebo and 225 mg dose groups was -2.81 days (95% CI -4.07 to
-1.55; p<0.0001), whereas the difference between the placebo and 675 mg dose
group was -2.64 days (-3.90 to -1.38; p<0.0001). LSM differences in the
reduction of headache-days were -2.63 days (-3.91 to -1.34; p<0.0001) between
the placebo group and 225 mg dose group and -2.58 days (-3.87 to 1.30; p
<0.0001) between the placebo group and the 675 mg dose group. Adverse events
occurred in 58 (56%) patients in the placebo group, 44 (46%) patients in the 225
mg dose group, and 57 (59%) patients in the 675 mg dose group; moderate or
severe adverse events were reported for 29 (27%) patients, 24 (25%) patients,
and 26 (27%) patients, respectively.
INTERPRETATION: TEV-48125, at doses of 225 mg and 675 mg given once every 28
days for 12 weeks, was safe, well tolerated, and effective as a preventive
treatment of high-frequency episodic migraine, thus supporting advancement of
the clinical development programme to phase 3 clinical trials.
FUNDING: Teva Pharmaceuticals. BACKGROUND: The calcitonin gene-related peptide (CGRP) pathway is a promising
target for preventive therapies in patients with migraine. We assessed the
safety and efficacy of AMG 334, a fully human monoclonal antibody against the
CGRP receptor, for migraine prevention.
METHODS: In this multicentre, randomised, double-blind, placebo-controlled,
phase 2 trial, patients aged 18-60 years with 4 to 14 migraine days per month
were enrolled at 59 headache and clinical research centres in North America and
Europe, and randomly assigned in a 3:2:2:2 ratio to monthly subcutaneous
placebo, AMG 334 7 mg, AMG 334 21 mg, or AMG 334 70 mg using a sponsor-generated
randomisation sequence centrally executed by an interactive voice response or
interactive web response system. Study site personnel, patients, and the sponsor
study personnel were masked to the treatment assignment. The primary endpoint
was the change in monthly migraine days from baseline to the last 4 weeks of the
12-week double-blind treatment phase. The primary endpoint was calculated using
the least squares mean at each timepoint from a generalised linear mixed-effect
model for repeated measures. Safety endpoints were adverse events, clinical
laboratory values, vital signs, and anti-AMG 334 antibodies. The study is
registered with ClinicalTrials.gov, number NCT01952574. An open-label extension
phase of up to 256 weeks is ongoing and will assess the long-term safety of AMG
334.
FINDINGS: From Aug 6, 2013, to June 30, 2014, 483 patients were randomly
assigned to placebo (n=160), AMG 334 7 mg (n=108), AMG 334 21 mg (n=108), or AMG
334 70 mg (n=107). The mean change in monthly migraine days at week 12 was -3·4
(SE 0·4) days with AMG 334 70 mg versus -2·3 (0·3) days with placebo (difference
-1·1 days [95% CI -2·1 to -0·2], p=0·021). The mean reductions in monthly
migraine days with the 7 mg (-2·2 [SE 0·4]) and the 21 mg (-2·4 [0·4]) doses
were not significantly different from that with placebo. Adverse events were
recorded in 82 (54%) patients who received placebo, 54 (50%) patients in the AMG
334 7 mg group, 54 (51%) patients in the AMG 334 21 mg group, and 57 (54%)
patients in the AMG 334 70 mg group. The most frequently reported adverse events
were nasopharyngitis, fatigue, and headache. Serious adverse events were
reported for one patient in the AMG 334 7 mg group (ruptured ovarian cyst) and
one patient in the AMG 334 70 mg group (migraine and vertigo); these events were
judged to be unrelated to AMG 334 treatment. Nine (3%) of 317 patients had
neutralising antibodies. No apparent association was recorded between patients
with positive anti-AMG 334 antibodies and adverse events. No clinically
significant vital signs, laboratory, or electrocardiogram findings were
recorded.
INTERPRETATION: These results suggest that AMG 334 70 mg might be a potential
therapy for migraine prevention in patients with episodic migraine and support
further investigation of AMG 334 in larger phase 3 trials.
FUNDING: Amgen. PURPOSE OF REVIEW: The results of phase 2 randomized controlled trials for the
prevention of episodic and chronic migraine demonstrating the efficacy and
safety of four mAbs targeting the calcitonin gene-related peptide (CGRP) pathway
[ALD403 (eptinezumab), AMG334 (erenumab), LY2951742 (galcanezumab) and TEV48125
(fremanezumab)] have been published recently, and phase 3 trials are in process.
This development will change headache management fundamentally. We aim to
summarize and compare the phase 2 data.
RECENT FINDINGS: The change from baseline in the number of migraine days at the
end of treatment in high-frequency episodic migraine was -1 (at weeks 5-8), -1.1
(at weeks 9-12), -1.2 (at weeks 9-12) and -2.6 (at weeks 9-12) days for ALD403,
AMG344, LY2951742 and TEV48125 (225 mg), respectively. Number needed to treats
for responders and odds ratio for any adverse event were 4.7, 6.2, 4.0 and 4.0
and 1.09, 0.96, 1.07 and 1.05, respectively.
SUMMARY: All four CGRP antibodies display comparable efficacy that does not
differ significantly from that of the currently available oral antimigraine
drugs. However, their safety and tolerability profiles as well as low frequency
of administration looks promising but remains to be verified in long-term and
large-scale trials. Considerations related to pregcy, risk for cardiovascular
effects and cost are subject for further evaluation. BACKGROUND: Fremanezumab, a humanized monoclonal antibody targeting calcitonin
gene-related peptide (CGRP), is being investigated as a preventive treatment for
migraine. We compared two fremanezumab dose regimens with placebo for the
prevention of chronic migraine.
METHODS: In this phase 3 trial, we randomly assigned patients with chronic
migraine (defined as headache of any duration or severity on ≥15 days per month
and migraine on ≥8 days per month) in a 1:1:1 ratio to receive fremanezumab
quarterly (a single dose of 675 mg at baseline and placebo at weeks 4 and 8),
fremanezumab monthly (675 mg at baseline and 225 mg at weeks 4 and 8), or
matching placebo. Both fremanezumab and placebo were administered by means of
subcutaneous injection. The primary end point was the mean change from baseline
in the average number of headache days (defined as days in which headache pain
lasted ≥4 consecutive hours and had a peak severity of at least a moderate level
or days in which acute migraine-specific medication [triptans or ergots] was
used to treat a headache of any severity or duration) per month during the 12
weeks after the first dose.
RESULTS: Of 1130 patients enrolled, 376 were randomly assigned to fremanezumab
quarterly, 379 to fremanezumab monthly, and 375 to placebo. The mean number of
baseline headache days (as defined above) per month was 13.2, 12.8, and 13.3,
respectively. The least-squares mean (±SE) reduction in the average number of
headache days per month was 4.3±0.3 with fremanezumab quarterly, 4.6±0.3 with
fremanezumab monthly, and 2.5±0.3 with placebo (P<0.001 for both comparisons
with placebo). The percentage of patients with a reduction of at least 50% in
the average number of headache days per month was 38% in the
fremanezumab-quarterly group, 41% in the fremanezumab-monthly group, and 18% in
the placebo group (P<0.001 for both comparisons with placebo). Abnormalities of
hepatic function occurred in 5 patients in each fremanezumab group (1%) and 3
patients in the placebo group (<1%).
CONCLUSIONS: Fremanezumab as a preventive treatment for chronic migraine
resulted in a lower frequency of headache than placebo in this 12-week trial.
Injection-site reactions to the drug were common. The long-term durability and
safety of fremanezumab require further study. (Funded by Teva Pharmaceuticals;
ClinicalTrials.gov number, NCT02621931 .). Treatment of migraine is on the cusp of a new era with the development of drugs
that target the trigeminal sensory neuropeptide calcitonin gene-related peptide
(CGRP) or its receptor. Several of these drugs are expected to receive approval
for use in migraine headache in 2018 and 2019. CGRP-related therapies offer
considerable improvements over existing drugs as they are the first to be
designed specifically to act on the trigeminal pain system, they are more
specific and they seem to have few or no adverse effects. CGRP receptor
antagonists such as ubrogepant are effective for acute relief of migraine
headache, whereas monoclonal antibodies against CGRP (eptinezumab, fremanezumab
and galcanezumab) or the CGRP receptor (erenumab) effectively prevent migraine
attacks. As these drugs come into clinical use, we provide an overview of
knowledge that has led to successful development of these drugs. We describe the
biology of CGRP signalling, summarize key clinical evidence for the role of CGRP
in migraine headache, including the efficacy of CGRP-targeted treatment, and
synthesize what is known about the role of CGRP in the trigeminovascular system.
Finally, we consider how the latest findings provide new insight into the
central role of the trigeminal ganglion in the pathophysiology of migraine. Objective - To evaluate 12-week changes from baseline of 2 disease-specific
patient-reported outcome (PRO) measures in adults with migraine treated with
galcanezumab, an investigational humanized antibody binding calcitonin
gene-related peptide (CGRP), or placebo. Background - Preventing
headache-related functional impairment is an important goal of migraine
preventive treatment and a measurement target for PROs. Understanding which
drugs have the potential to improve patient functioning in addition to
preventing migraine headaches is vital to lessening patient burden.
Design/Methods - This Phase 2b double-blind, randomized, placebo-controlled
study enrolled adults with episodic migraine. Galcanezumab (120 mg subcutaneous
injection; n = 60) or placebo (n = 127) was administered every 28 days for 12
weeks. Post hoc secondary analyses were conducted for those who completed 12
weeks of treatment on 2 PROs: The Migraine-Specific Quality of Life
Questionnaire (MSQ) v2.1 and the Headache Impact Test™ (HIT-6). Results -
Analysis of covariance revealed significant differences in least square mean
changes from baseline between galcanezumab and placebo for all MSQ domains
including total mean change placebo of 18.63, galcanezumab of 27.36 (95% CI
2.449, 15.008; P-value of .0067); Role Function-Restrictive mean change placebo
of 22.40, galcanezumab of 31.92 (95% CI 2.636, 16.518; P-value of .0071); Role
Function-Preventive mean change placebo of 13.43, galcanezumab of 19.76 (95% CI
0.476, 12.185; P-value of .0342); and Emotional Function mean change placebo of
16.88, galcanezumab of 26.61 (95% CI 2.789, 16.674; P-value of .0063). At
baseline, mean number of migraine headache days (MHDs) did not correlate with
MSQ total scores or HIT-6. At 12 weeks post-treatment, MHD correlated with MSQ
and HIT-6 scores (all P < .0001). Change in MHD was associated with change in
MSQ domains and change in HIT-6 scores (all P < .0001). Conclusions - In
comparison with placebo, treatment with galcanezumab was associated with
significant functional improvements as reflected by changes in MSQ scores.
Change in MHD was associated with improvements in MSQ and reductions in HIT-6
scores, indicating the clinical importance of these changes in relation to PROs
that measure function. BACKGROUND: A substantial proportion of patients with migraine does not respond
to, or cannot tolerate, oral preventive treatments. Erenumab is a novel
CGRP-receptor antibody with preventive efficacy in migraine. We assessed its
efficacy and tolerability in patients with episodic migraine in whom previous
treatment with two-to-four migraine preventives had been unsuccessful.
METHODS: LIBERTY was a 12-week, double-blind, placebo-controlled randomised
study at 59 sites in 16 countries. Eligible patients were aged 18-65 years and
had a history of episodic migraine with or without aura for at least 12 months,
had migraine for an average of 4-14 days per month during the 3 months before
screening, and had been treated unsuccessfully (in terms of either efficacy or
tolerability, or both) with between two and four preventive treatments. Eligible
participants were randomly assigned (1:1) to receive either erenumab 140 mg (via
two 70 mg injections) or placebo every 4 weeks subcutaneously for 12 weeks.
Randomisation was by interactive response technology and was stratified by
monthly frequency of migraine headache (4-7 vs 8-14 migraine days per month)
during the baseline phase. Cenduit generated the randomisation list and assigned
participants to groups. Participants, investigators, people doing various
assessments, and the study sponsor were masked to treatment assignment. The
primary endpoint was the proportion of patients achieving a 50% or greater
reduction in the mean number of monthly migraine days during weeks 9-12.
Efficacy was measured in the full analysis set, which included all randomly
assigned patients who started their assigned treatment and completed at least
one post-baseline monthly migraine day measurement. Safety and tolerability were
assessed by recording adverse events and by physical examination, assessment of
vital signs, clinical laboratory assessments, and electrocardiography. Safety
was assessed in all randomly assigned patients who received at least one dose of
study drug. This trial is registered with ClinicalTrials.gov, number
NCT03096834. The trial is closed to new participants, but the open-label
extension phase is ongoing.
FINDINGS: Between March 20, 2017, and Oct 27, 2017, 246 participants were
randomly assigned, 121 to the erenumab group and 125 to the placebo group. 95 of
246 (39%) participants had previously unsuccessfully tried two preventive drugs,
93 (38%) had tried three, and 56 (23%) had tried four. At week 12, 36 (30%)
patients in the erenumab had a 50% or greater reduction from baseline in the
mean number of monthly migraine days, compared with 17 (14%) in the placebo
group (odds ratio 2·7 [95% CI 1·4-5·2]; p=0·002). The tolerability and safety
profiles of erenumab and placebo were similar. The most frequent
treatment-emergent adverse event was injection site pain, which occurred in
seven (6%) participants in both groups.
INTERPRETATION: Compared with placebo, erenumab was efficacious in patients with
episodic migraine who previously did not respond to or tolerate between two and
four previous migraine preventive treatments. Erenumab might be an option for
patients with difficult-to-treat migraine who have high unmet needs and few
treatment options.
FUNDING: Novartis Pharma. BACKGROUND: Galcanezumab, a humanized monoclonal antibody that selectively binds
to the calcitonin gene-related peptide, has demonstrated in previous Phase 2 and
Phase 3 clinical studies (≤6-month of treatment) a reduction in the number of
migraine headache days and improved patients' functioning. This study evaluated
the safety and tolerability, as well as the effectiveness of galcanezumab for up
to 12 months of treatment in patients with migraine.
METHODS: Patients diagnosed with episodic or chronic migraine, 18 to 65 years
old, that were not exposed previously to galcanezumab, were randomized to
receive galcanezumab 120 mg or 240 mg, administered subcutaneously once monthly
for a year. Safety and tolerability were evaluated by frequency of
treatment-emergent adverse events (TEAEs), serious adverse events (SAEs), and
adverse events (AEs) leading to study discontinuation. Laboratory values, vital
signs, electrocardiograms, and suicidality were also analyzed. Additionally,
overall change from baseline in the number of monthly migraine headache days,
functioning, and disability were assessed.
RESULTS: One hundred thirty five patients were randomized to each galcanezumab
dose group. The majority of patients were female (> 80%) and on average were
42 years old with 10.6 migraine headache days per month at baseline. 77.8% of
the patients completed the open-label treatment phase, 3.7% of patients
experienced an SAE, and 4.8% discontinued due to AEs. TEAEs with a
frequency ≥ 10% of patients in either dose group were injection site pain,
nasopharyngitis, upper respiratory tract infection, injection site reaction,
back pain, and sinusitis. Laboratory values, vital signs, or electrocardiograms
did not show anyclinically meaningful differences between galcanezumab
dosesOverall mean reduction in monthly migraine headache days over 12 months for
the galcanezumab dose groups were 5.6 (120 mg) and 6.5 (240 mg). Level of
functioning was improved and headache-related disability was reduced in both
dose groups.
CONCLUSION: Twelve months of treatment with self-administered injections of
galcanezumab was safe and associated with a reduction in the number of monthly
migraine headache days. Safety and tolerability of the 2 galcanezumab dosing
regimens were comparable.
TRIAL REGISTRATION: ClinicalTrials.gov as NCT02614287 , posted November 15,
2015. These data were previously presented as a poster at the International
Headache Congress 2017: PO-01-184, Late-Breaking Abstracts of the 2017
International Headache Congress. (2017). Cephalalgia, 37(1_suppl), 319-374. Migraine affects the daily life of millions of people around the world. The most
well-known disabling symptom associated with this illness is the intense
headache. Nowadays, there are treatments that can diminish the level of pain.
OnabotulinumtoxinA (BoNT-A) has become a very popular medication for treating
migraine headaches in those cases in which other medication is not working,
typically in chronic migraines. Currently, the positive response to Botox
treatment is not clearly understood, yet understanding the mechanisms that
determine the effectiveness of the treatment could help with the development of
more effective treatments. To solve this problem, this paper sets up a realistic
scenario of electronic medical records of migraineurs under BoNT-A treatment
where some clinical features from real patients are labeled by doctors. Medical
registers have been preprocessed. A label encoding method based on simulated
annealing has been proposed. Two methodologies for predicting the results of the
first and the second infiltration of the BoNT-A based treatment are contempled.
Firstly, a strategy based on the medical HIT6 metric is described, which
achieves an accuracy over 91%. Secondly, when this value is not available,
several classifiers and clustering methods have been performed in order to
predict the reduction and adverse effects, obtaining an accuracy of 85%. Some
clinical features as Greater occipital nerves (GON), chronic migraine time
evolution and others have been detected as relevant features when examining the
prediction models. The GON and the retroocular component have also been
described as important features according to doctors. Several lines of evidence pointed to an important role for CGRP in migraine.
These included the anatomic colocalization of CGRP and its receptor in sensory
fibers innervating pain-producing meningeal blood vessels, its release by
trigeminal stimulation, the observation of elevated CGRP in the cranial
circulation during migraine with normalization concomitant with headache relief
by sumatriptan, and translational studies with intravenous (IV) CGRP that evoked
migraine only in migraineurs. The development of small molecule CGRP receptor
antagonists (CGRP-RAs) that showed clinical antimigraine efficacy acutely and
prophylactically in randomized placebo-controlled clinical trials subsequently
gave definitive pharmacological proof of the importance of CGRP in migraine.
More recently, CGRP target engagement imaging studies using a CGRP receptor PET
ligand [11 C]MK-4232 demonstrated that there was no brain CGRP receptor
occupancy at clinically effective antimigraine doses of telcagepant, a
prototypic CGRP-RA. Taken together, these data indicated that (1) the
therapeutic site of action of the CGRP-RAs was peripheral not central; (2) that
IV CGRP had most likely evoked migraine through an action at sites outside the
blood-brain barrier; and (3) that migraine pain was therefore, at least in part,
peripheral in origin. The evolution of CGRP migraine science gave impetus to the
development of peripherally acting drugs that could modulate CGRP chronically to
prevent frequent episodic and chronic migraine. Large molecule biologic antibody
(mAb) approaches that are given subcutaneously to neutralize circulating CGRP
peptide (fremanezumab, galcanezumab) or block CGRP receptors (erenumab) have
shown consistent efficacy and tolerability in multicenter migraine prevention
trials and are now approved for clinical use. Eptinezumab, a CGRP neutralizing
antibody given IV, shows promise in late stage clinical development. Recently,
orally administered next-generation small molecule CGRP-RAs have been shown to
have safety and efficacy in acute treatment (ubrogepant and rimegepant) and
prevention (atogepant) of migraine, giving additional CGRP-based therapeutic
options for migraine patients. Author information:
(1)Neuroscience Section, Department of Applied Clinical Sciences and
Biotechnology, University of L'Aquila, via Vetoio, 67100, L'Aquila, Italy.
[email protected].
(2)Department of Neurology, Danish Headache Center, Rigshospitalet Glostrup,
Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen,
Denmark.
(3)Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany.
(4)Department of Neurology, Leiden University Medical Center, Leiden, The
Netherlands.
(5)1st Department of Neurology, National and Kapodistrian University of Athens,
Athens, Greece.
(6)Department of Clinical and Molecular Medicine, Sapienza University, Rome,
Italy. BACKGROUND: Chronic migraines affect approximately 2 percent of the U.S.
population and cost an estimated $17 billion per year. OnabotulinumtoxinA
(botulinum toxin type A) is a U.S. Food and Drug Administration-approved
prophylactic medication for chronic migraine headaches and is best injected in a
targeted fashion into specific trigger sites. The purpose of this study was to
determine the cost-effectiveness of long-term, targeted botulinum toxin type A
versus peripheral trigger site deactivation surgery for the treatment of
migraine headaches.
METHODS: A Markov model was constructed to examine long-term, targeted botulinum
toxin type A versus peripheral trigger site deactivation surgery. Costs,
utilities, and other model inputs were identified from the literature. One-way
and probabilistic sensitivity analyses were performed. An incremental
cost-effectiveness ratio under $50,000 per quality-adjusted life-year was
considered cost-effective.
RESULTS: The mean cost of peripheral trigger site deactivation surgery was
$10,303, with an effectiveness of 7.06; whereas the mean cost of long-term,
targeted botulinum toxin type A was $36,071, with an effectiveness of 6.34.
Trigger-site deactivation surgery is more effective and less costly over the
time horizon of the model. One-way sensitivity analysis revealed that surgery is
the most cost-effective treatment in patients requiring treatment for greater
than 6.75 years.
CONCLUSIONS: Based on this model, peripheral trigger site deactivation surgery
is the more cost-effective option for treating refractory migraine headaches
requiring treatment beyond 6.75 years. The model reveals that peripheral
trigger-site deactivation surgery is more effective and less costly than
long-term, targeted botulinum toxin type A over the course of a patient's
lifetime. Migraine is the third-most prevalent disease in the world and affects
approximately 39 million individuals in the United States alone. Migraine occurs
in nearly 1 in 7 individuals between 15 and 49 years of age and is 3 times more
frequent in women than in men. The Food and Drug Administration (FDA) recently
approved 3 new humanized monoclonal antibodies that target calcitonin
gene-related peptide (CGRP): erenumab, fremanezumab, and galcanezumab. The
agents either bind to the CGRP receptor (erenumab) or bind to the CGRP ligand
(fremanezumab and galcanezumab) and block its binding to the receptor. All 3
products are indicated for preventative treatment of episodic or chronic
migraine in adults. The available studies to date document that these agents
reduce migraine attacks. The CGRP monoclonal antibodies offer patients new
options once they have exhausted other treatments. Medical research continues to focus on developing specific treatment strategies,
including biological products that are effective and have a good safety profile.
Due to their novelty, an updated overall view is offered on some neurological
diseases which benefit from monoclonal antibodies (mAbs), for better treatment
in clinical decisions. An extensive literature review was performed using PubMed
with the following search terms: 'monoclonal antibodies' and 'history of
monoclonal antibodies' and 'monoclonal antibodies in neurology'. The following
information was collected: the era before the discoveries of mAbs, the stage of
implementation of biotechnologies for mAbs, and the clinical trials submitted at
https://clinicaltrials.gov/ with patients suffering from neurological diseases
treated with mAbs. Since 2004, mAbs have been used to treat several neurological
diseases, yielding new therapeutic perspectives: natalizumab, alemtuzumab and
ocrelizumab for multiple sclerosis, eculizumab for myasthenia gravis, erenumab
and frenazumab for migraine, galcanezumab for migraine and cluster headache,
eculizumab for neuromyelitis optica spectrum disorder. As in other cases, drug
repurposing is applied to monoclonal antibodies, saving time and money. These
innovative therapies are more effective and can treat previously untreatable
diseases. As better understanding of the pathogenic mechanisms of neurological
diseases is gained, additional mAbs are expected to be developed at a lower cost
and with better safety profile compared with current treatment options. BACKGROUND: Galcanezumab is a monoclonal antibody (mAb) that binds calcitonin
gene-related peptide (CGRP) and is indicated for the preventive treatment of
migraine. Galcanezumab demonstrated early onset of effect in patients with
migraine but it is unknown whether the same holds true for patients who have not
benefited from multiple prior migraine preventives.
METHODS: Patients with episodic or chronic migraine from a 3-month, randomized,
double-blind, placebo-controlled, phase 3b study (CONQUER) who had 2 to 4
migraine preventive medication category failures in the past 10 years were
randomized 1:1 to placebo (N = 230) or galcanezumab 120 mg/month (240 mg loading
dose; N = 232). In this post-hoc analysis, change from baseline in number of
monthly and weekly migraine headache days was assessed. Monthly onset of effect
was the earliest month at which significant improvement with galcanezumab
compared to placebo was achieved and maintained at all subsequent months. Weekly
onset was the initial week at which statistical separation was achieved and
maintained at all subsequent weeks during that month. Proportion of patients
with migraine headache days in the first week of treatment, and patients
achieving ≥50%, ≥75%, and 100% response by month and week were also assessed.
RESULTS: Galcanezumab-treated patients had a significantly greater reduction in
monthly migraine headache days starting at month 1, which remained significant
for all subsequent months compared to placebo (all p ≤ 0.0001, month 1 mean
change from baseline: placebo - 0.7; galcanezumab - 4.0). Weekly migraine
headache days was significantly reduced in galcanezumab-treated patients
starting at week 1 and continued for each subsequent week of month 1 compared to
placebo (all p < 0.01, week 1 mean change from baseline: placebo - 0.2;
galcanezumab - 1.1). A significantly smaller percentage of patients had a
migraine headache on the first day after galcanezumab treatment compared to
placebo (28.4% vs 39.2%) and at each subsequent day during week 1 (all
p < 0.05). A greater proportion of galcanezumab-treated patients achieved ≥50%,
≥75%, and 100% response at months 1-3 (all p < 0.05) and at weeks 1-4 of month 1
compared to placebo (all p < 0.01).
CONCLUSION: Galcanezumab showed early onset of effect beginning the day after
treatment initiation in patients who had not previously benefited from migraine
preventive treatments.
TRIAL REGISTRATION: ClinicalTrials.gov , NCT03559257 . Registered 18 June 2018. INTRODUCTION: Erenumab, a first-in-class monoclonal antibody targeting the
calcitonin gene-related peptide pathway, was approved by the US Food and Drug
Administration in 2018 for the prevention of migraine in adults. There is
limited data available on its impact in real-world settings. The study aim was
to characterize the real-world treatment profiles, clinical outcomes, and
healthcare resource utilization of patients prescribed erenumab from select
major US headache centers.
METHODS: A retrospective chart review of patients with migraine treated with
erenumab for at least 3 months across five major headache centers was conducted.
Data was collected from patient charts between April 2019 and April 2020 and
included patient and clinical characteristics, migraine medication use, and
outpatient visits. The date of the first prescription fill of erenumab was
defined as the index date. The baseline period comprised the 3 months prior to
the index date and the study period comprised the at least 3 months on erenumab
treatment.
RESULTS: Data from a total of 1034 patients with chronic migraine with a mean of
9.3 months of erenumab treatment were analyzed. Patients were on average
48 years old, 86% were female, and 79% were white. Patients had a mean of 5
preventive treatment failures prior to erenumab initiation. Patients used a mean
of 2 preventive treatments (excluding erenumab) and 2 acute treatments during
baseline and study periods. Among patients with effectiveness data, 45% of
patients had improvement in physician-reported migraine severity and 35%
experienced at least 50% reduction in mean headache/migraine days per month. The
average number of monthly outpatient visits was 0.43 and 0.30 before and after
erenumab initiation, respectively.
CONCLUSION: In this predomitly refractory chronic migraine population treated
in select headache centers, patients had fewer headache/migraine days per month
and outpatient visits after initiating erenumab. However, patients largely
continued to be managed via a polypharmacy approach after erenumab initiation. BACKGROUND: Galcanezumab is a calcitonin gene-related peptide (CGRP) monoclonal
antibody (mAb) indicated for the preventive treatment of migraine. While
galcanezumab has demonstrated efficacy in patients who did not respond to prior
preventive medications in general, its efficacy in patients who did not benefit
from individual, commonly prescribed preventive treatments due to inadequate
efficacy or safety/tolerability remains unknown.
METHODS: CONQUER was a 3-month, randomized, double-blind, placebo-controlled,
phase 3b study that enrolled patients with episodic or chronic migraine who had
2 to 4 migraine preventive medication category failures in the past 10 years.
Patients were randomly assigned 1:1 to receive placebo (N = 230) or galcanezumab
120 mg/month (240 mg loading dose; N = 232). Post hoc analyses were conducted to
determine the efficacy of galcanezumab in patients who had not benefited from
six of the most commonly prescribed migraine preventive medications. The mean
change from baseline in monthly migraine headache days and ≥ 50 % response rates
were assessed over months 1-3. Improvement in Migraine-Specific Questionnaire
Role Function-Restrictive (MSQ-RFR) scores were assessed at month 3. The
endpoints were estimated via mixed model with repeated measures.
RESULTS: The most common treatment failures due to inadequate efficacy or
safety/tolerability, which at least 20 % of patients reported trying without
benefit, included topiramate, amitriptyline, propranolol, valproate or
divalproex, onabotulinum toxin A, and metoprolol. Patients who had not
previously benefited from these treatments had a greater mean reduction in
monthly migraine headache days across months 1-3 in the galcanezumab group
compared to placebo (all p < 0.01). More patients treated with galcanezumab
experienced a ≥ 50 % reduction from baseline in monthly migraine headache days
across months 1-3 compared to placebo (all p < 0.05). Galcanezumab-treated
patients had a greater improvement in mean MSQ-RFR scores at month 3 compared to
placebo (all p < 0.01).
CONCLUSIONS: In this population, galcanezumab was effective in reducing monthly
migraine headache days, improving response rates, and enhancing quality of life
in patients who had not previously benefited from topiramate, amitriptyline,
propranolol, valproate or divalproex, onabotulinum toxin A, and/or metoprolol
due to inadequate efficacy or safety/tolerability.
TRIAL REGISTRATION: ClinicalTrials.gov NCT03559257 (CONQUER). OBJECTIVE: To evaluate the impact of fremanezumab on the severity and duration
of remaining migraine attacks in patients with chronic migraine (CM) or episodic
migraine (EM).
BACKGROUND: Fremanezumab is a fully humanized monoclonal antibody (IgGΔa) that
selectively targets calcitonin gene-related peptide and is efficacious in
reducing migraine frequency.
METHODS: This exploratory post hoc analysis included data from three randomized,
double-blind, 12-week, phase 3 studies (HALO CM, HALO EM, and FOCUS). In all
three studies, patients with CM or EM were randomized 1:1:1 to receive
subcutaneous quarterly fremanezumab (month 1/2/3: 675 mg/placebo/placebo),
monthly fremanezumab (month 1/2/3: 675 mg [CM], 225 mg [EM]/225 mg/225 mg), or
matched monthly placebo. Changes from baseline were evaluated in the proportion
of headache days of at least moderate severity, peak severity of headache days,
mean monthly headache hours (of any severity and at least moderate severity),
and mean headache hours per headache day of any severity.
RESULTS: A total of 2843 patients were randomized with 2823 patients included in
the efficacy analyses across all studies (HALO CM, N = 1121; HALO EM, N = 865;
FOCUS, N = 837). At study baseline, mean (standard deviation [SD]) monthly
number of headache days rated moderate or severe in the quarterly fremanezumab,
monthly fremanezumab, and placebo groups, respectively, were 13.2 (5.5), 12.8
(5.8), and 13.3 (5.8) in HALO CM; 7.2 (3.1), 6.8 (2.9), and 6.9 (3.1) in HALO
EM; and 12.4 (5.8), 12.7 (5.8), and 12.8 (5.9) in FOCUS. Patients experienced
significant least-squares mean (LSM; 95% confidence interval) percent reductions
from baseline in monthly number of headache days rated moderate or severe during
the 12 weeks: HALO CM, quarterly fremanezumab, 34.5% (-39.8, -29.2) and monthly
fremanezumab, 36.2% (-41.4, -31.0) vs. placebo, 19.6% (-20.0, -14.3); HALO EM,
quarterly fremanezumab, 40.7% (-47.8, -33.5) and monthly fremanezumab, 43.4%
(-50.4, -36.3) vs. placebo, 17.9% (-24.9, -11.0); and FOCUS, quarterly
fremanezumab, 36.5% (-41.9, -31.1) and monthly fremanezumab, 38.6% (-44.0,
-33.3) vs. placebo, 3.5% (-8.9, 1.8); all p < 0.0001. At study baseline, mean
(SD) number of monthly headache hours rated moderate or severe in the quarterly
fremanezumab, monthly fremanezumab, and placebo groups, respectively, were 66.4
(58.8), 68.0 (53.9), and 68.5 (57.0) in HALO CM; 33.3 (25.4), 31.7 (23.7), and
31.6 (23.2) in HALO EM; and 59.2 (54.7), 64.3 (65.2), and 65.9 (70.2) in FOCUS.
Significant reductions were observed in LSM (standard error) number of monthly
headache hours of at least moderate severity: HALO CM, quarterly fremanezumab,
24.4 (2.5) and monthly fremanezumab, 26.4 (2.3) vs. placebo, 14.1 (2.5); HALO
EM, quarterly fremanezumab, 14.5 (1.4) and monthly fremanezumab, 15.5 (1.3) vs.
placebo, 8.1 (1.3); and FOCUS, quarterly fremanezumab, 16.8 (3.0) and monthly
fremanezumab, 18.3 (3.0) vs. placebo, 2.3 (3.0); all p < 0.001.
CONCLUSION: These analyses demonstrated that quarterly or monthly treatment with
fremanezumab significantly reduced headache severity and duration in patients
with CM or EM, including in patients with documented inadequate response to two
to four prior migraine preventive medication classes. BACKGROUND: Fremanezumab, a fully humanized monoclonal antibody (IgG2Δa)
selectively targets the calcitonin gene-related peptide and has proven efficacy
for the preventive treatment of migraine. In this study, we evaluated the
long-term efficacy, safety, and tolerability of monthly and quarterly
fremanezumab.
METHODS: Episodic migraine and chronic migraine patients completing the 12-week
double-blind period of the FOCUS trial entered the 12-week open-label extension
and received 3 monthly doses of fremanezumab (225 mg). Changes from baseline in
monthly migraine days, monthly headache days of at least moderate severity, days
of acute headache medication use, days with photophobia/phonophobia, days with
nausea or vomiting, disability scores, and proportion of patients achieving
a ≥50% or ≥75% reduction in monthly migraine days were evaluated.
RESULTS: Of the 807 patients who completed the 12-week double-blind treatment
period and entered the open-label extension, 772 patients completed the study.
In the placebo, quarterly fremanezumab, and monthly fremanezumab dosing
regimens, respectively, patients had fewer average monthly migraine days (mean
[standard deviation] change from baseline: - 4.7 [5.4]; - 5.1 [4.7]; - 5.5
[5.0]), monthly headache days of at least moderate severity (- 4.5 [5.0]; - 4.8
[4.5]; - 5.2 [4.9]), days per month of acute headache medication use (- 4.3
[5.2]; - 4.9 [4.6]; - 4.8 [4.9]), days with photophobia/phonophobia (- 3.1
[5.3]; - 3.4 [5.3]; - 4.0 [5.2]), and days with nausea or vomiting (- 2.3 [4.6];
- 3.1 [4.5]; - 3.0 [4.4]). During the 12-week open-label extension, 38%, 45%,
and 46% of patients, respectively, achieved a ≥50% reduction and 16%, 15%, and
20%, respectively, achieved a ≥75% reduction in monthly migraine days.
Disability scores were substantially improved in all 3 treatment groups. There
were low rates of adverse events leading to discontinuation (<1%).
CONCLUSION: Fremanezumab demonstrated sustained efficacy up to 6 months and was
well tolerated in patients with episodic migraine or chronic migraine and
documented inadequate response to multiple migraine preventive medication
classes.
TRIAL REGISTRATION: ClinicalTrials.gov NCT03308968 (FOCUS). Conflict of interest statement: SJT has received grants for research (no
personal compensation) from Allergan/Abbvie, Amgen, Eli Lilly, Lundbeck,
Neurolief, Novartis, Satsuma, and Zosano, has served as a consultant for Aeon,
Allergan/Abbvie, AlphaSights, Amgen, Atheneum, Axsome Therapeutics, Becker
Pharmaceutical Consulting, ClearView Healthcare Partners, CoolTech, CRG, Currax,
DRG, Eli Lilly, ExpertConnect, FCB Health, GLG, Guidepoint Global, Health
Science Communications, HMP Communications, Impel, InteractiveForums, Krog and
Partners, Lundbeck, M3 Global Research, MJH Holdings, Neurolief, Novartis,
Palion Medical, Pulmatrix, SAI MedPartners, Satsuma, Spherix Global Insights,
Strategy Inc, System Analytic, Taylor and Francis, Teva, Theranica, UnityHA,
Xoc, and Zosano, has received salary from Dartmouth‐Hitchcock Medical Center,
American Headache Society, and the Thomas Jefferson University, and has received
continuing medical education honoraria from the Annenberg Center for Health
Sciences, American Academy of Neurology, American Headache Society, Catamount
Medical Education, Diamond Headache Clinic, Forefront Collaborative, Haymarket
Medical Education, Peerview, Medical Education Speakers Network, Migraine
Association of Ireland, North American Center for CME, The Ohio State
University, Physicians’ Education Resource, PlatformQ Education, Primed, Texas
Neurological Society, WebMD/Medscape. SL has received advisory or consulting
fees from Amgen, Alder, Biohaven, Impel, Eli Lilly, Lundbeck, and Teva, and
receives compensation from Premera as a member of the Pharmacy & Therapeutics
committee. MA has received personal fees from Alder, Allergan, Amgen, Alder, Eli
Lilly, Novartis, and Teva; has participated in clinical trials as the principal
investigator for Alder, Allergan, Amgen, ElectroCore, Eli Lilly, Novartis and
Teva; has received a research grant form Novartis; has no ownership interest and
does not own stocks of any pharmaceutical company; serves as associate editor of
Cephalalgia, associate editor of The Journal of Headache and Pain, and associate
editor of Headache, and is President of the International Headache Society. TS
has received consulting fees from Alder, Allergan, Amgen, Aural Analytics,
Avanir, Cipla, Dr. Reddy's, Eli Lilly, Ipsen Bioscience, Nocira, Novartis,
Second Opinion, and Teva. JA has received consulting fees from Alder, Allergan,
electroCore, Eli Lilly, Impel, Promius, and Teva; honoraria from Alder,
Allergan, Amgen, Avanir, electroCore, Eli Lilly, Promius, and Teva; and serves
as section editor for Current Pain and Headache Reports. JS, DEC, AW, and GPdSL
are employees and stockholders of Amgen. JK is an employee and stockholder of
Novartis. BACKGROUND: Calcitonin gene-related peptide (CGRP) (receptor) antibodies
(erenumab, fremanezumab and galcanezumab) are increasingly used in prophylactic
treatment of migraine. In the approval studies, severely affected patients with
migraine and chronic daily headache without any headache free days were
excluded. Thus, less is known about the effectiveness of CGRP antibody treatment
in this cohort.
METHODS: Clinical routine data of 32 patients with migraine and daily headache
were analysed after three months of treatment with a CGRP antibody (16 erenumab,
7 galcanezumab, 9 fremanezumab), including changes of monthly headache days
(MHD) monthly migraine days (MMD) and monthly acute medication intake (AMD) as
well as migraine characteristics. Statistical analysis was performed with the
Wilcoxon-Test. Migraine characteristics were analysed descriptively.
RESULTS: The number of MHD was significantly reduced (mean reduction (standard
error), p-value): (-4.2 (1.3), p = 0.009) as well as MMD (-4.3 (1.6),
p = 0.033). Four patients (13 %) reached a 50 % reduction regarding MHD and 8
patients (25 %) regarding MMD, migraine duration and intensity improved under
therapy.
CONCLUSIONS: Despite the low responder rate, CGRP antibodies can be effective at
least in a few cases of severely affected patients with drug resistant migraine
and chronic daily headache.
TRIAL REGISTRATION: Retrospective registered. BACKGROUND: Erenumab, the first-in-class fully human monoclonal antibody
targeting the calcitonin gene-related peptide receptor, was shown to be
efficacious and safe for the prophylactic treatment of migraine in adults in
randomized clinical trials. Large-scale, real-world evidence in multi-centre
settings is still needed to confirm these results. Erenumab patient profiles
outside clinical trials and physicians' treatment patterns, as well as data from
patients treated in Germany, a severely impacted population, are not published
yet.
METHODS: TELESCOPE was a multi-centre survey gathering real-world data from 45
German headache centres between July 2019 and December 2019. The project
consisted of two parts. In the first part, treating physicians shared their
experiences on current erenumab treatment with regard to patient profiles,
treatment patterns and treatment responses. In the second part, a retrospective
chart review was conducted of 542 migraine patients treated with erenumab for at
least three months. Treatment responses focused on various aspects of patients'
quality of life.
RESULTS: The analysis of 542 patients' charts revealed that three-month
treatment with erenumab significantly reduced monthly headaches, migraine and
acute medication days. Furthermore, headache intensity and frequency were
reduced in over 75 % and accompanying aura in 35 % of patients. The clinical
global impression scale revealed a general improvement in 91 % of patients.
According to the treating physicians' professional judgement, 83 % of patients
responded to erenumab and 80 % were satisfied with the treatment. Physicians
evaluated restricted quality of life, the number of monthly migraine days and
previous, prophylactic treatments as the main components of the current patient
profile for monoclonal antibody recipients. Based on the assessment of
physicians, erenumab reduced migraine symptoms in 65 % and increased quality of
life in more than 75 % of their patients.
CONCLUSIONS: TELESCOPE confirms positive treatment responses with erenumab shown
in clinical trials in a real-world multi-centre setting. The results show
consistently positive experiences of physicians utilizing erenumab in clinical
practice and underline that therapy with this monoclonal antibody is effective
in migraine patients, particular in those, who have failed several prophylactic
therapies. |
What is the most common N6-methyladenosine (m6A) methylation modification site of RUNX1T1? | The RRACH motif is the most common N6-methyladenosine (m6A) methylation modification site of RUNX1T1. | BACKGROUND: Runt-related transcription factor 1 (RUNX1T1) isoforms are involved
in adipogenesis. RUNX1T1 is mediated by the fat mass and obesity-associated
(FTO). However, the extent to which RUNX1T1 single-nucleotide polymorphisms
(SNPs) are associated with obesity risk or metabolic abnormalities in a
community population basis is unknown.
METHODS: Samples were obtained from the Australian Crossroads study bio-bank.
SNPs located in the coding region and 3'untranslated regions of RUNX1T1 with
minor allele frequency ≥0.05 were analysed using Taqman genotyping assays.
RESULTS: Eight candidate SNPs were genotyped successfully in 1440 participants.
Of these SNPs only rs34269950 located in the 'RRACH' motif, the most common
N6-methyladenosine (m6A) methylation modification site (recognized by FTO), was
significantly associated with obesity risk and metabolic abnormalities.
Specifically, compared to AA genotype, rs34269950 del/del genotype was
associated with a 1.47 [95% confidence interval (CI): 1.01-2.14, P = 0.042] fold
higher rate of obesity risk. Additionally, the del/del genotype was associated
with a 60% increased risk of metabolic syndrome (MetS) [odds ratio (OR) = 1.60,
95% CI: 1.10-2.32, P = 0.015], in comparison to the AA genotype. Finally,
rs34269950 del/del increased the risk of a larger waist circumference (OR =
1.65, 95% CI: 1.15-2.36, P = 0.007), but not other components of MetS.
CONCLUSION: Our study demonstrates that RUNX1T1 rs34269950, located in a
potential FTO recognition motif, is significantly associated with waist
circumference. This provides novel evidence to suggest SNPs located in RRACH
motif may be involved in RNA m6A modification and mechanistic pathways that
influence abdominal obesity. |
Describe GREEKC | The COST Action Gene Regulation Ensemble Effort for the Knowledge Commons (GREEKC, CA15205, www.greekc.org) organized nine workshops in a four-year period, starting September 2016. The workshops brought together experts from all over the world working on various steps in the knowledge management process that focuses on understanding gene regulatory mechanisms. | Author information:
(1)Systems Biology Group, Department of Biology, Norwegian University of Science
and Technology, Trondheim, Norway. Electronic address: [email protected].
(2)Faculty of Information & Communication Technology, University of Malta,
Msida, Malta.
(3)Departamento de Informática y Sistemas, Universidad de Murcia, IMIB-Arrixaca,
CP 30100, Murcia, Spain.
(4)Swiss Institute of Bioinformatics, Quartier Sorge, Bâtiment Amphipôle, 1015
Lausanne, Switzerland.
(5)Systems Biology and Bioinformatics Laboratory (SysBioLab), Centre of Marine
Sciences (CCMAR), University of Algarve, 8005-139 Faro, Portugal.
(6)SIB Swiss Institute of Bioinformatics, 1 Rue Michel-Servet, 1204 Geneva,
Switzerland.
(7)Institute of Protein Research, Russian Academy of Sciences, 142290,
Institutskaya 4, Pushchino, Russia.
(8)Department of Biology, University of Rome Tor Vergata, Rome, Italy.
(9)Department of Molecular Biology, Faculty of Science, Radboud University, PO
box 9101, Nijmegen 6500HG, the Netherlands.
(10)Functional Gene Annotation, Pre-clinical and Fundamental Science, Institute
of Cardiovascular Science, University College London, 5 University Street,
London WC1E 6JF, UK.
(11)Vavilov Institute of General Genetics, Russian Academy of Sciences, 119991,
Gubkina 3, Moscow, Russia.
(12)European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus,
Hinxton, Cambridge CB10 1SD, UK.
(13)Department DIBEST, University of Calabria, Rende, Italy.
(14)Fondazione Human Technopole, Department of Biology, Via Cristina Belgioioso,
171, 20157 Milan, Italy.
(15)Department of Biomedical Informatics, University of Utah, 421 Wakara Way
#140, Salt Lake City, UT 84108, United States.
(16)Institute of Medical Informatics, Statistics and Documentation, Medical
University of Graz, Auenbruggerpl. 2, Graz, Austria.
(17)Systems Biology Group, Department of Biology, Norwegian University of
Science and Technology, Trondheim, Norway.
(18)European Molecular Biology Laboratory, European Bioinformatics Institute,
Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK.
(19)Department of Clinical and Molecular Medicine, Norwegian University of
Science and Technology, 7491 Trondheim, Norway. |
Which receptors are targeted by Tirzepatide? | Tirzepatide is dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist that demonstrated substantially greater glucose control and weight loss (WL) compared with selective GLP-1RA dulaglutide. | OBJECTIVE: To determine the effect of tirzepatide, a dual agonist of
glucose-dependent insulinotropic polypeptide and glucagon-like peptide 1
receptors, on biomarkers of nonalcoholic steatohepatitis (NASH) and fibrosis in
patients with type 2 diabetes mellitus (T2DM).
RESEARCH DESIGN AND METHODS: Patients with T2DM received either once weekly
tirzepatide (1, 5, 10, or 15 mg), dulaglutide (1.5 mg), or placebo for 26 weeks.
Changes from baseline in alanine aminotransferase (ALT), aspartate
aminotransferase (AST), keratin-18 (K-18), procollagen III (Pro-C3), and
adiponectin were analyzed in a modified intention-to-treat population.
RESULTS: Significant (P < 0.05) reductions from baseline in ALT (all groups),
AST (all groups except tirzepatide 10 mg), K-18 (tirzepatide 5, 10, 15 mg), and
Pro-C3 (tirzepatide 15 mg) were observed at 26 weeks. Decreases with tirzepatide
were significant compared with placebo for K-18 (10 mg) and Pro-C3 (15 mg) and
with dulaglutide for ALT (10, 15 mg). Adiponectin significantly increased from
baseline with tirzepatide compared with placebo (10, 15 mg).
CONCLUSIONS: In post hoc analyses, higher tirzepatide doses significantly
decreased NASH-related biomarkers and increased adiponectin in patients with
T2DM. The effect of dual glucose-dependent insulinotropic polypeptide (GIP) and
glucagon-like peptide-1 (GLP-1) receptor agonist (RA) tirzepatide on gastric
emptying (GE) was compared to that of GLP-1RAs in non-clinical and clinical
studies. GE was assessed following acute and chronic treatment with tirzepatide
in diet-induced obese mice versus semaglutide or long-acting GIP analogue alone.
Participants [with and without type 2 diabetes (T2DM)] from a phase 1, 4-week
multiple dose study received tirzepatide, dulaglutide or placebo. GE was
assessed by acetaminophen absorption. In mice, tirzepatide delayed GE to a
similar degree to that achieved with semaglutide; however, these acute
inhibitory effects were abolished after 2 weeks of treatment. GIP analogue alone
had no effect on GE or on GLP-1's effect on GE. In participants with and without
T2DM, once-weekly tirzepatide (≥5 and ≥4.5 mg, respectively) delayed GE after a
single dose. This effect diminished after multiple doses of tirzepatide or
dulaglutide in healthy participants. In participants with T2DM treated with an
escalation schedule of tirzepatide 5/5/10/10 or 5/5/10/15 mg, a residual GE
delay was still observed after multiple doses. These data suggest that
tirzepatide's activity on GE is comparable to that of selective GLP-1RAs. INTRODUCTION: The glucagon-like peptide-1 (GLP-1) receptor agonists (RA) have
increasingly gained prominence in the treatment of type 2 diabetes (T2D) based
on their glycemic benefits and favorable body weight and cardiorenal effects.
Despite this, continued development of therapeutics with superior efficacy is
important to help address persistent challenges in the attainment of metabolic
goals in many patients with T2D.
AREAS COVERED: Tirzepatide is an unimolecular dual glucose-dependent
insulinotropic polypeptide (GIP)/GLP-1 RA in development for the treatment of
T2D. This review summarizes key characteristics of tirzepatide and Phase 1 and
Phase 2 clinical trial efficacy and safety results. Additionally, it provides an
overview of the ongoing Phase 3 clinical trial program in T2D and briefly
summarizes recently initiated studies in patients with obesity and nonalcoholic
steatohepatitis. Information in this review comes primarily from published
clinical trials, manufacturer's websites, and ClinicalTrials.gov.
EXPERT OPINION: Based on data from Phase 2 trials, tirzepatide has the potential
to be the most efficacious therapy in T2D with respect to both glucose and body
weight control. Data from the ongoing Phase 3 clinical trial program should
start to become available in late 2020 and will determine the future course of
this promising therapeutic agent. CONTEXT: Novel dual glucose-dependent insulinotropic polypeptide (GIP) and
glucagon-like peptide-1 (GLP-1) receptor agonist (RA) tirzepatide demonstrated
substantially greater glucose control and weight loss (WL) compared with
selective GLP-1RA dulaglutide.
OBJECTIVE: Explore mechanisms of glucose control by tirzepatide.
DESIGN: Post hoc analyses of fasting biomarkers and multiple linear regression
analysis.
SETTING: Forty-seven sites in 4 countries.
PATIENTS OR OTHER PARTICIPANTS: Three hundred and sixteen subjects with type 2
diabetes.
INTERVENTIONS: Tirzepatide (1, 5, 10, 15 mg), dulaglutide (1.5 mg), placebo.
MAIN OUTCOME MEASURES: Analyze biomarkers of beta-cell function and insulin
resistance (IR) and evaluate WL contributions to IR improvements at 26 weeks.
RESULTS: Homeostatic model assessment (HOMA) 2-B significantly increased with
dulaglutide and tirzepatide 5, 10, and 15 mg compared with placebo (P ≤ .02).
Proinsulin/insulin and proinsulin/C-peptide ratios significantly decreased with
tirzepatide 10 and 15 mg compared with placebo and dulaglutide (P ≤ .007).
Tirzepatide 10 and 15 mg significantly decreased fasting insulin (P ≤ .033) and
tirzepatide 10 mg significantly decreased HOMA2-IR (P = .004) compared with
placebo and dulaglutide. Markers of improved insulin sensitivity (IS)
adiponectin, IGFBP-1, and IGFBP-2 significantly increased by 1 or more doses of
tirzepatide (P < .05). To determine whether improvements in IR were directly
attributable to WL, multiple linear regression analysis with potential
confounding variables age, sex, metformin, triglycerides, and glycated
hemoglobin A1c was conducted. WL significantly (P ≤ .028) explained only 13% and
21% of improvement in HOMA2-IR with tirzepatide 10 and 15 mg, respectively.
CONCLUSIONS: Tirzepatide improved markers of IS and beta-cell function to a
greater extent than dulaglutide. IS effects of tirzepatide were only partly
attributable to WL, suggesting dual receptor agonism confers distinct mechanisms
of glycemic control. Glucagon-like peptide 1 (GLP-1) based therapy is an established treatment option
for the management of type 2 diabetes mellitus (T2DM) and is recommended early
in the treatment algorithm owing to glycaemic efficacy, weight reduction and
favourable cardiovascular outcomes. Glucose-dependent insulinotropic polypeptide
(GIP), on the other hand, was thought to have no potential as a glucose-lowering
therapy because of observations showing no insulinotropic effect from
supraphysiological infusion in people with T2DM. However, emerging evidence has
illustrated that co-infusion of GLP-1 and GIP has a synergetic effect, resulting
in significantly increased insulin response and glucagonostatic response,
compared with separate administration of each hormone. These observations have
led to the development of a dual GIP/GLP-1 receptor agonist, known as a
'twincretin'. Tirzepatide is a novel dual GIP/GLP-1 receptor agonist formulated
as a synthetic peptide containing 39 amino acids, based on the native GIP
sequence. Pre-clinical trials and phase 1 and 2 clinical trials indicate that
tirzepatide has potent glucose lowering and weight loss with adverse effects
comparable to those of established GLP-1 receptor agonists. The long-term
efficacy, safety and cardiovascular outcomes of tirzepatide will be investigated
in the SURPASS phase 3 clinical trial programme. In this paper, we will review
the pre-clinical and phase 1 and 2 trials for tirzepatide in the management of
T2DM and give an overview of the SURPASS clinical trials. Tirzepatide (LY3298176), a dual GIP and GLP-1 receptor (GLP-1R) agonist,
delivered superior glycemic control and weight loss compared with GLP-1R agonism
in patients with type 2 diabetes. However, the mechanism by which tirzepatide
improves efficacy and how GIP receptor (GIPR) agonism contributes is not fully
understood. Here, we show that tirzepatide is an effective insulin sensitizer,
improving insulin sensitivity in obese mice to a greater extent than GLP-1R
agonism. To determine whether GIPR agonism contributes, we compared the effect
of tirzepatide in obese WT and Glp-1r-null mice. In the absence of
GLP-1R-induced weight loss, tirzepatide improved insulin sensitivity by
enhancing glucose disposal in white adipose tissue (WAT). In support of this, a
long-acting GIPR agonist (LAGIPRA) was found to enhance insulin sensitivity by
augmenting glucose disposal in WAT. Interestingly, the effect of tirzepatide and
LAGIPRA on insulin sensitivity was associated with reduced branched-chain amino
acids (BCAAs) and ketoacids in the circulation. Insulin sensitization was
associated with upregulation of genes associated with the catabolism of glucose,
lipid, and BCAAs in brown adipose tissue. Together, our studies show that
tirzepatide improved insulin sensitivity in a weight-dependent and -independent
manner. These results highlight how GIPR agonism contributes to the therapeutic
profile of dual-receptor agonism, offering mechanistic insights into the
clinical efficacy of tirzepatide. BACKGROUND: Tirzepatide is a novel dual glucose-dependent insulinotropic
polypeptide and GLP-1 receptor agonist under development for the treatment of
type 2 diabetes. We aimed to assess the efficacy and safety of tirzepatide
versus titrated insulin degludec in people with type 2 diabetes inadequately
controlled by metformin with or without SGLT2 inhibitors.
METHODS: In this open-label, parallel-group, multicentre (122 sites),
multinational (13 countries), phase 3 study, eligible participants (aged ≥18
years) had a baseline glycated haemoglobin (HbA1c) of 7·0-10·5%, body-mass index
of at least 25 kg/m2, stable weight, and were insulin-naive and treated with
metformin alone or in combination with an SGLT2 inhibitor for at least 3 months
before screening. Participants were randomly assigned (1:1:1:1), using an
interactive web-response system, to once-weekly subcutaneous injection of
tirzepatide (5, 10, or 15 mg) or once-daily subcutaneous injection of titrated
insulin degludec, and were stratified by country, HbA1c, and concomitant use of
oral antihyperglycaemic medications. Tirzepatide was initially given at 2·5 mg
and the dose was escalated by 2·5 mg every 4 weeks until the assigned dose was
reached. Insulin degludec was initially given at 10 U per day and was titrated
once weekly to a fasting self-monitored blood glucose of less than 5·0 mmol/L
(<90 mg/dL), following a treat-to-target algorithm, for 52 weeks. The primary
efficacy endpoint was non-inferiority of tirzepatide 10 mg or 15 mg, or both,
versus insulin degludec in mean change from baseline in HbA1c at week 52. Key
secondary efficacy endpoints were non-inferiority of tirzepatide 5 mg versus
insulin degludec in mean change from baseline in HbA1c at week 52, superiority
of all doses of tirzepatide versus insulin degludec in mean change from baseline
in HbA1c and bodyweight, and the proportion of participants achieving HbA1c of
less than 7·0% (<53 mmol/mol) at week 52. We used a boundary of 0·3% to
establish non-inferiority in HbA1c difference between treatments. Efficacy and
safety analyses were assessed in the modified intention-to-treat population (all
participants who received at least one dose of study drug). This trial is
registered with ClinicalTrials.gov, number NCT03882970, and is complete.
FINDINGS: Between April 1 and Nov 15, 2019, we assessed 1947 participants for
eligibility, 1444 of whom were randomly assigned to treatment. The modified
intention-to-treat population was 1437 participants from the tirzepatide 5 mg
(n=358), tirzepatide 10 mg (n=360), tirzepatide 15 mg (n=359), and insulin
degludec (n=360) groups. From a mean baseline HbA1c of 8·17% (SD 0·91), the
reductions in HbA1c at week 52 were 1·93% (SE 0·05) for tirzepatide 5 mg, 2·20%
(0·05) for tirzepatide 10 mg, and 2·37% (0·05) for tirzepatide 15 mg, and 1·34%
(0·05) for insulin degludec. The non-inferiority margin of 0·3% was met. The
estimated treatment difference (ETD) versus insulin degludec ranged from -0·59%
to -1·04% for tirzepatide (p<0·0001 for all tirzepatide doses). The proportion
of participants achieving a HbA1c of less than 7·0% (<53 mmol/mol) at week 52
was greater (p<0·0001) in all three tirzepatide groups (82%-93%) versus insulin
degludec (61%). At week 52, from a baseline of 94·3 kg (SD 20·1), all three
tirzepatide doses decreased bodyweight (-7·5 kg to -12·9 kg), whereas insulin
degludec increased bodyweight by 2·3 kg. The ETD versus insulin degludec ranged
from -9·8 kg to -15·2 kg for tirzepatide (p<0·0001 for all tirzepatide doses).
The most common adverse events in tirzepatide-treated participants were mild to
moderate gastrointestinal events that decreased over time. A higher incidence of
nausea (12-24%), diarrhoea (15-17%), decreased appetite (6-12%), and vomiting
(6-10%) was reported in participants treated with tirzepatide than in those
treated with insulin degludec (2%, 4%, 1%, and 1%, respectively). Hypoglycaemia
(<54 mg/dL or severe) was reported in five (1%), four (1%), and eight (2%)
participants on tirzepatide 5, 10, and 15 mg, respectively, versus 26 (7%) on
insulin degludec. Treatment discontinuation due to an adverse event was more
common in the tirzepatide groups than in the insulin degludec group. Five
participants died during the study; none of the deaths were considered by the
investigators to be related to the study treatment.
INTERPRETATION: In patients with type 2 diabetes, tirzepatide (5, 10, and 15 mg)
was superior to titrated insulin degludec, with greater reductions in HbA1c and
bodyweight at week 52 and a lower risk of hypoglycaemia. Tirzepatide showed a
similar safety profile to that of GLP-1 receptor agonists.
FUNDING: Eli Lilly and Company. Publisher: Les agonistes des récepteurs du glucagon-like peptide-1 (GLP-1) sont
les agents antidiabétiques qui, outre une baisse importante du taux
d’hémoglobine glyquée, offrent la perte pondérale la plus marquée, en augmentant
la satiété par un effet central, prédomit et périphérique. Le liraglutide et
le sémaglutide sont développés pour le traitement de l’obésité, indépendamment
de la présence d’un diabète de type 2. Trois approches sont possibles pour
potentialiser la perte de poids: augmenter la posologie, compte tenu de
l’existence d’une relation dose-réponse, ajouter un inhibiteur des
sodium-glucose cotransporteurs 2 qui exerce un effet complémentaire grâce à une
fuite calorique urinaire (glucosurie), ou encore combiner les effets de deux
hormones incrétines (GLP-1 et Glucose-dependent Insulin Releasing Polypeptide),
comme avec le puissant double agoniste tirzépatide en développement. There is a new generation of antiobesity drugs in development or just arriving
on the scene. First, setmelanotide has been approved for three of the ultrarare
genetic conditions that cause obesity-pro-opiomelanocortin deficiency,
proprotein convertase subtilisin and kexin type 1 (an important enzyme in the
melanocortin pathway) and leptin receptor deficiency. Setmelanotide marks the
first in a personalized medicine approach to obesity. Second, semaglutide 2.4 mg
once weekly has been submitted to regulators in the United States and the
European Union for approval for patients with obesity (body mass index [BMI] ≥30
kg/m2) or overweight (BMI ≥27 kg/m2) and at least one weight related
comorbidity. This drug has been studied in five phase 3 clinical trials, four
discussed herein: semaglutide produces roughly twice as much weight loss as we
have seen in older antiobesity medications. Semaglutide is already in use for
treatment of diabetes and, as a glucagon-like peptide 1 (GLP-1) receptor analog,
is part of a class of drugs used widely in diabetes. Tirzepatide, a
glucose-insulin peptide and GLP-1 dual agonist is in phase 3 study for obesity
management, and bimagrumab is a new agent in phase 2 with a unique mechanism of
action; they are generating much interest. The purpose of this narrative review
is lay the groundwork for a discussion of the clinical impact of these new
medications on the clinical practice of obesity. Further, these developments
shall be used to launch a speculation of what is likely to be their impact on
the future of obesity pharmacotherapy. In a phase 2 trial of once-weekly tirzepatide (1, 5, 10, or 15 mg), dulaglutide
(1.5 mg), or placebo, the dual glucose-dependent insulinotropic polypeptide and
glucagon-like peptide-1 receptor agonist tirzepatide dose-dependently reduced
HbA1c and body weight in patients with type 2 diabetes. In this post hoc
analysis, inflammation, endothelial dysfunction, and cellular stress biomarkers
were measured at baseline, 4, 12, and 26 weeks to evaluate the additional
effects of tirzepatide on cardiovascular risk factors. At 26 weeks, tirzepatide
10 and 15 mg decreased YKL-40 (also known as chitinase-3 like-protein-1),
intercellular adhesion molecule 1 (ICAM-1), leptin, and growth differentiation
factor 15 levels versus baseline, and YKL-40 and leptin levels versus placebo
and dulaglutide. Tirzepatide 15 mg also decreased ICAM-1 levels versus placebo
and dulaglutide, and high-sensitivity C-reactive protein (hsCRP) levels versus
baseline and placebo, but not dulaglutide. GlycA, interleukin 6, vascular cell
adhesion molecule 1, and N-terminal-pro hormone B-type natriuretic peptide
levels were not significantly changed in any group. YKL-40, hsCRP, and ICAM-1
levels rapidly decreased within 4 weeks of treatment with tirzepatide 10 and
15 mg, whereas the decrease in leptin levels was more gradual and did not
plateau by 26 weeks. In this hypothesis-generating exploratory analysis,
tirzepatide decreased several biomarkers that have been associated with
cardiovascular risk. CONTEXT: Tirzepatide substantially reduced hemoglobin A1c (HbA1c) and body
weight in subjects with type 2 diabetes (T2D) compared with the glucagon-like
peptide 1 receptor agonist dulaglutide. Improved glycemic control was associated
with lower circulating triglycerides and lipoprotein markers and improved
markers of beta-cell function and insulin resistance (IR), effects only
partially attributable to weight loss.
OBJECTIVE: Assess plasma metabolome changes mediated by tirzepatide.
DESIGN: Phase 2b trial participants were randomly assigned to receive weekly
subcutaneous tirzepatide, dulaglutide, or placebo for 26 weeks. Post hoc
exploratory metabolomics and lipidomics analyses were performed.
SETTING: Post hoc analysis.
PARTICIPANTS: 259 subjects with T2D.
INTERVENTION(S): Tirzepatide (1, 5, 10, 15 mg), dulaglutide (1.5 mg), or
placebo.
MAIN OUTCOME MEASURE(S): Changes in metabolite levels in response to tirzepatide
were assessed against baseline levels, dulaglutide, and placebo using
multiplicity correction.
RESULTS: At 26 weeks, a higher dose tirzepatide modulated a cluster of
metabolites and lipids associated with IR, obesity, and future T2D risk.
Branched-chain amino acids, direct catabolic products glutamate,
3-hydroxyisobutyrate, branched-chain ketoacids, and indirect byproducts such as
2-hydroxybutyrate decreased compared to baseline and placebo. Changes were
significantly larger with tirzepatide compared with dulaglutide and directly
proportional to reductions of HbA1c, homeostatic model assessment 2-IR indices,
and proinsulin levels. Proportional to metabolite changes, triglycerides and
diglycerides were lowered significantly compared to baseline, dulaglutide, and
placebo, with a bias toward shorter and highly saturated species.
CONCLUSIONS: Tirzepatide reduces body weight and improves glycemic control and
uniquely modulates metabolites associated with T2D risk and metabolic
dysregulation in a direction consistent with improved metabolic health. Tirzepatide is a dual gastric inhibitory peptide/glucagon-like peptide 1
(GIP/GLP-1) receptor agonist formulated as a synthetic linear peptide, based on
the native GIP sequence. It has a prolonged half-life of 5 days, which enables
once-weekly dosing. Studies have hitherto demonstrated its superiority in
achieving optimal glycaemic control and body weight management, as compared with
various agents used in the treatment of type 2 diabetes mellitus (T2DM),
including GLP-1 receptor agonists. Thus, it is expected to enrich our
therapeutic armamentarium in T2DM. However, further experience, notably longer
follow-up data and information on cardiovascular effects, is still needed. Tirzepatide is a novel once-a-week dual glucose-dependent insulinotropic
polypeptide and glucagon-like peptide-1 receptor agonist, currently under trial
to assess glycemic efficacy and safety in people with type 2 diabetes. A
systematic review and meta-analysis were conducted to investigate the efficacy
of tirzepatide on glycated hemoglobin (HbA1c, %), fasting serum glucose (mg/dL),
and body weight (kg) in patients with uncontrolled type 2 diabetes (HbA1c >
7.0%). Mean changes for efficacy and proportions (safety) with corresponding 95%
confidence intervals (CIs) were used to provide pooled estimates. A total of
four randomized controlled trials, comprising 2783 patients of whom 69.4% (n =
1934) were treated with 5 mg (n = 646), 10 mg (n = 641), or 15 mg (n = 647) of
tirzepatide, were compared to the placebo (n = 192) or the selective GLP-1
receptor agonist (n = 523). The pooled analysis showed that tirzepatide
treatment resulted in a greater lowering of the HbA1c (-1.94%, 95% CI: -2.02 to
-1.87), fasting serum glucose (-54.72 mg/dL, 95% CI: -62.05 to -47.39), and body
weight (-8.47, 95% CI: -9.66 to -7.27). We also found that improvement in the
HbA1c levels was still maintained at weeks 26 and 40 from the long-term trials.
As for safety, only 3% experienced hypoglycemia, and 4% (95% CI: 2 to 6)
experienced serious adverse events, while the discontinuation of therapy
percentage was 7% (95% CI: 5 to 8). Tirzepatide significantly improved glycemic
control and body weight and had an acceptable safety profile, indicating that it
is an effective therapeutic option for glucose-lowering in patients with type 2
diabetes mellitus. Incretin hormones are peptides released in the intestine in response to the
presence of nutrients in its lumen. The main incretins are glucagon-like
peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). GLP-1
stimulates insulin secretion, inhibits glucagon secretion at pancreatic α cells
and has also extrapancreatic influences as slowing of gastric emptying which
increases the feeling of satiety. GIP is the main incretin hormone in healthy
people, causative of most the incretin effects, but the insulin response after
GIP secretion in type 2 diabetes mellitus (T2DM) is strongly reduced. Therefore,
in the past GIP has been considered an unappealing therapeutic target for T2DM.
This conception has been changing during recent years, since it has been
reported that resistance to GIP can be reversed and its effectiveness restored
by improving glycemic control. This fact paved the way for the development of a
GIP receptor agonist-based therapy for T2DM, looking also for the possibility of
finding a combined GLP-1/GIP receptor agonist. In this framework, the novel dual
GIP and GLP-1 receptor agonist tirzepatide seems to be not just a new
antidiabetic medication. Administered as a subcutaneous weekly injection, it is
a manifold single pharmacological agent that has the ability to significantly
lower glucose levels, as well as improve insulin sensitivity, reduce weight and
amend dyslipidemia favorably modifying the lipid profile. Tirzepatide and
additional dual GLP-1/GIP receptor agonists that could eventually be developed
in the future seem to be a promising furthest advance for the management of
several cardiometabolic settings. Obviously, it is too early to be overly
hopeful since it is still necessary to determine the long-term effects of these
compounds and properly verify the potential cardiovascular benefits. Anyway, we
are currently facing a novel and very appealing therapeutic option. |
Is esophageal adenocarcinoma associated with aberrant glycosylation? | Yes,
Altered glycoprotein expression has been demonstrated in tissue from patients with Barrett's esophagus and esophageal cancer but the mechanisms regarding such changes are unknown. | Aberrant glycosylation has been implicated in various types of cancers and
changes in glycosylation may be associated with signaling pathways during
maligt transformation. Glycomic profiling of blood serum, in which cancer
cell proteins or their fragments with altered glycosylation patterns are shed,
could reveal the altered glycosylation. We performed glycomic profiling of serum
from patients with no known disease (N = 18), patients with high grade dysplasia
(HGD, N = 11) and Barrett's esophagus (N = 5), and patients with esophageal
adenocarcinoma (EAC, N = 50) in an attempt to delineate distinct differences in
glycosylation between these groups. The relative intensities of 98 features were
significantly different among the disease onsets; 26 of these correspond to
known glycan structures. The changes in the relative intensities of three of the
known glycan structures predicted esophageal adenocarcinoma with 94% sensitivity
and better than 60% specificity as determined by receiver operating
characteristic (ROC) analysis. We have demonstrated that comparative glycomic
profiling of EAC reveals a subset of glycans that can be selected as candidate
biomarkers. These markers can differentiate disease-free from HGD, disease-free
from EAC, and HGD from EAC. The clinical utility of these glycan biomarkers
requires further validation. It is generally accepted that esophageal adenocarcinoma arises from a Barrett's
metaplastic lesion. Altered glycoprotein expression has been demonstrated in
tissue from patients with Barrett's esophagus and esophageal cancer but the
mechanisms regarding such changes are unknown. The bile acid deoxycholic acid
(DCA) alters many cell signaling pathways and is implicated in esophageal cancer
progression. We have demonstrated that DCA disrupts Golgi structure and affects
protein secretion and glycosylation processes in cell lines derived from normal
squamous epithelium (HET-1A) and Barrett's metaplastic epithelium (QH). Cell
surface expression of glycans was identified using carbohydrate-specific probes
(wheat germ agglutinate, conconavalin A, peanut agglutinin, lithocholic acid and
Ulex europaeus agglutinin) that monitored N-glycosylation, O-glycosylation and
core fucosylation in resting and DCA-treated cells. DCA altered intracellular
localization and reduced cell surface expression of N-acetyl-D-glucosamine,
α-methyl-mannopyranoside (Man/Glc) and fucose in both cell lines. Furthermore,
DCA reduced the expression of epithelial growth factor receptor and E-cadherin
in a manner analogous to treatment of cells with the N-glycan biosynthesis
inhibitor tunicamycin. This is the first study to identify an altered Golgi
structure and glycomic profile in response to DCA in esophageal epithelial
cells, a process which could potentially contribute to metaplasia, dysplasia and
cancer of the esophagus. Glycosylation is among the most common post translation modifications of
proteins in humans. Decades of research have demonstrated that aberrant
glycosylation can lead to maligt degeneration. Glycoproteomic studies in the
past several years have identified techniques that can successfully characterize
a glycan or glycan profile associated with a high-grade dysplastic or maligt
state. This review summarizes the current glycomic and glycoproteomic literature
with specific reference to esophageal cancer. Esophageal adenocarcinoma
represents a highly morbid and mortal cancer with a defined progression from
metaplasia (Barrett's esophagus) to dysplasia to neoplasia. This disease is
highlighted because (1) differences in glycan profiles between the stages of
disease progression have been described in the glycoproteomic literature; (2) a
glycan biomarker that identifies a given stage may be used as a predictor of
disease progression and thus may have significant influence over clinical
management; and (3) the differences in glycan profiles between disease and
disease-free states in esophageal cancer are more dramatic than in other
cancers. This study aimed to investigate the association of IgG glycosylation and
esophageal precancerosis for squamous cell carcinoma and determine its role in
inflammation. Primary glycans selected by the least absolute shrinkage and
selection operator (LASSO) algorithm were validated using univariate and
multivariate logistics models plus restricted cubic spline functions. In total,
24 direct glycans and 27 derived traits were detected, among which four glycans
and three derived traits were primarily selected. Then, GP5 (adjusted OR:
0.805), GP17 (adjusted OR: 1.305), G12n (adjusted OR: 1.271), Gal_1 (adjusted
OR: 0.776) and Fuc (adjusted OR: 0.737) were validated and significantly
associated with esophageal precancerosis. In addition, there was a consistent
positive association in GP17 and G12n and a negative association in GP5, Gal_1,
and Fuc by restricted cubic spline function. Compared with esophageal
inflammation, GP17, G12n, and Fuc were still independently associated with
precancerosis. In brief, the IgG glycosylation profile was independently
associated with esophageal precancerosis beyond inflammation, which could be an
early biomarker for esophageal cancer.Prevention Relevance: IgG glycosylation
profile is associated with esophageal precancerosis and specific IgG glycans
involves in the early stage of esophageal cancer, which is independent of
inflammation. |
What is the function of a chaperonin? | Molecular chaperones promote the correct folding of proteins in aggregation-prone cellular environments by stabilizing nascent polypeptide chains and providing appropriate folding conditions. They are involved in the development of pathological processes, including--atherosclerosis and coronary heart disease. | BACKGROUND: Mitochondria are known to be a major target during ischemic cardiac
injury. Previous studies have shown that in rodent myogenic cells and in the
hearts of transgenic mice in which the heat shock or stress protein 70 is
increased, there is a marked tolerance to ischemia/reperfusion injury. Two other
heat shock proteins (HSP60 and HSP10) are known to form, within the
mitochondria, a chaperonin complex that is important for mitochondrial protein
folding and function. We were then interested in investigating whether increased
expression of these two stress proteins is able to protect myogenic cells
against ischemia/reperfusion injury.
METHODS AND RESULTS: We generated recombit adenoviral vectors containing
HSP60, HSP10, or a combination of the two genes. These adenoviral constructs
overexpress significant amounts of these stress proteins in both rat neonatal
cardiomyocytes and the myogenic H9 c2 cell line. Cells infected with an
adenoviral construct overexpressing both HSP60 and HSP10 were found to be
protected against simulated ischemia, whereas cells infected with adenoviral
constructs overexpressing only HSP60 or HSP10 alone were not rendered tolerant
to simulated ischemic injury.
CONCLUSIONS: These results suggest that the simultaneous expression of these two
proteins that form a chaperonin complex in the mitochondria plays an important
role in the survival of myogenic cells after ischemia/reperfusion injury. Co-chaperonins from diverse organisms exhibit mobile loops which fold into a
beta hairpin conformation upon binding to the chaperonin. GroES, Gp31, and human
Hsp10 mobile loops exhibit a preference for the beta hairpin conformation in the
free co-chaperonins, and the conformational dynamics of the human Hsp10 mobile
loop appear to be restricted by nascent hairpin formation. Backbone
conformational entropy must weigh against binding of co-chaperonins to
chaperonins, and thus the conformational preferences of the loops may strongly
influence chaperonin-binding affinity. Indeed, subtle mutations in the loops
change GroEL-binding affinity and cause defects in chaperonin function, and
these defects can be suppressed by mutations in GroEL which compensate for the
changes in affinity. The fact that high-affinity co-chaperonin binding impairs
chaperonin function has implications for the mechanism of chaperonin-assisted
protein folding. Heat shock proteins (HSPs) 60 and 10 are stress-inducible mitochondrial matrix
proteins that form a chaperonin complex that is important for mitochondrial
protein folding and function. The effect of cerebral ischemia on mitochondrial
HSPs is unclear. The topographical and chronological patterns of HSP60 and HSP10
messenger ribonucleic acid (mRNA) expression and induction were investigated in
the rat focal cerebral ischemia model. Focal cerebral ischemia was produced by
transient middle cerebral artery occlusion for 30 or 90 min. Expression of mRNAs
was analyzed using reverse transcription-polymerase chain reaction (RT-PCR) and
in situ hybridization. RT-PCR analysis showed that both HSP60 and HSP10 mRNA
levels increased significantly in the ischemic cortex from 4 to 24 h of
reperfusion after 30 min of occlusion. In situ hybridization analysis
demonstrated significant induction of both mRNAs in the whole ischemic cortex
after 30 min of occlusion and in the dorsomedial border (penumbra) of the
ischemic cortex and ipsilateral hippocampus after 90 min of occlusion.
Expression patterns and the timing of the induction of both HSP60 and HSP10
mRNAs were identical throughout the experiments. Simultaneous induction of the
mRNAs for the mitochondrial chaperonins, HSP60 and HSP10, in various regions in
focal cerebral ischemia demonstrates that mitochondrial stress conditions
persist concomitantly with cytosolic stress conditions in focal cerebral
ischemia. Chaperonins are large oligomers made up of two superimposed rings, each
enclosing a cavity used for the folding of other proteins. Among the
chaperonins, the eukaryotic cytosolic chaperonin CCT is the most complex, not
only with regard to its subunit composition but also with respect to its
function, still not well understood. Unlike the more well studied eubacterial
chaperonin GroEL, which binds any protein that presents stretches of hydrophobic
residues, CCT recognises in its substrates specific binding determits and
interacts with them through particular combinations of CCT subunits. Folding
then occurs after the conformational changes induced in the chaperonin upon
nucleotide binding have occurred, through a mechanism that, although still
poorly defined, clearly differs from the one established for GroEL. Although CCT
seems to be mainly involved in the folding of actin and tubulin, other
substrates involved in various cellular roles are beginning to be characterised,
including many WD40-repeat, 7-blade propeller proteins. Eukaryotic prefoldin (PFD) is a heterohexameric chaperone with a jellyfish-like
structure whose function is to deliver nonnative target proteins, principally
actins and tubulins, to the eukaryotic cytosolic chaperonin for facilitated
folding. Here we demonstrate that functional PFD can spontaneously assemble from
its six constituent individual subunits (PFD1-PFD6), each expressed as a
recombit protein. Using engineered forms of PFD assembled in vitro, we show
that the tips of the PFD tentacles are required to form binary complexes with
authentic target proteins. We show that PFD uses the distal ends of different
but overlapping sets of subunits to form stable binary complexes with different
target proteins, namely actin and alpha- and beta-tubulin. We also present data
that suggest a model for the order of these six subunits within the hexamer. Our
data are consistent with the hypothesis that PFD, like the eukaryotic cytosolic
chaperonin, has co-evolved specifically to facilitate the folding of its target
proteins. Chaperonins assist in the acquisition of native protein structure in the cell by
providing a shielded environment for a folding polypeptide chain, generated by
the interior surface of their cylindrical structure. The folding chain is
isolated from the highly crowded cytoplasm, but at the same time confined within
the chaperonin folding cage. Both confinement and macromolecular crowding can
affect folding kinetics and yields, the modus operandi of chaperonins and their
interaction with their protegés. Recent experimental data, as well as computer
simulations, provide increasing evidence that the particular physico-chemical
conditions prevailing in the cellular interior have to be taken into account
when trying to unravel the processes of cellular protein folding. The major heat shock protein, chaperonin 60, has been established to have
intercellular signaling activity in addition to its established protein-folding
function. Mycobacterium tuberculosis is one of a small proportion of bacteria to
encode two chaperonin 60 proteins. We have demonstrated that chaperonin 60.1
from this bacterium is a very active stimulator of human monocytes. To determine
structure/function relationships of chaperonin 60.1 we have cloned and expressed
the apical, equatorial, and intermediate domains of this protein. We have found
that the signaling activity of M. tuberculosis chaperonin 60.1 resides in the
equatorial domain. This activity of the recombit equatorial domain was
completely blocked by treating the protein with proteinase K, ruling out
lipopolysaccharide contamination as the cause of the cell activation. Blockade
of the activity of the equatorial domain by anti-CD14 monoclonal antibodies
reveals that this domain activates monocytes by binding to CD14. Looking at the
oligomeric state of the active proteins, using native gel electrophoresis and
protein cross-linking we found that recombit M. tuberculosis chaperonin 60.1
fails to form the prototypic tetradecameric structure of chaperonin 60 proteins
under the conditions tested and only forms dimers. It is therefore concluded
that the monocyte-stimulating activity of M. tuberculosis Cpn60.1 resides in the
monomeric subunit and within this subunit the biological activity is due to the
equatorial domain. Chaperonins are large ring assemblies that assist protein folding to the native
state by binding nonnative proteins in their central cavities and then, upon
binding ATP, release the substrate protein into a now-encapsulated cavity to
fold productively. Two families of such components have been identified: type I
in mitochondria, chloroplasts, and the bacterial cytosol, which rely on a
detachable "lid" structure for encapsulation, and type II in archaea and the
eukaryotic cytosol, which contain a built-in protrusion structure. We discuss
here a number of issues under current study. What is the range of substrates
acted on by the two classes of chaperonin, in particular by GroEL in the
bacterial cytoplasm and CCT in the eukaryotic cytosol, and are all these
substrates subject to encapsulation? What are the determits for substrate
binding by the type II chaperonins? And is the encapsulated chaperonin cavity a
passive container that prevents aggregation, or could it be playing an active
role in polypeptide folding? The eukaryotic cytosolic chaperonin containing TCP-1 (CCT) has an important
function in maintaining cellular homoeostasis by assisting the folding of many
proteins, including the cytoskeletal components actin and tubulin. Yet the
nature of the proteins and cellular pathways dependent on CCT function has not
been established globally. Here, we use proteomic and genomic approaches to
define CCT interaction networks involving 136 proteins/genes that include links
to the nuclear pore complex, chromatin remodelling, and protein degradation. Our
study also identifies a third eukaryotic cytoskeletal system connected with CCT:
the septin ring complex, which is essential for cytokinesis. CCT interactions
with septins are ATP dependent, and disrupting the function of the chaperonin in
yeast leads to loss of CCT-septin interaction and aberrant septin ring assembly.
Our results therefore provide a rich framework for understanding the function of
CCT in several essential cellular processes, including epigenetics and cell
division. Chaperonins are macromolecular machines that assist in protein folding. The
archaeon Methanosarcina mazei has acquired numerous bacterial genes by
horizontal gene transfer. As a result, both the bacterial group I chaperonin,
GroEL, and the archaeal group II chaperonin, thermosome, coexist. A
proteome-wide analysis of chaperonin interactors was performed to determine the
differential substrate specificity of GroEL and thermosome. At least 13% of
soluble M. mazei proteins interact with chaperonins, with the two systems having
partially overlapping substrate sets. Remarkably, chaperonin selectivity is
independent of phylogenetic origin and is determined by distinct structural and
biochemical features of proteins. GroEL prefers well-conserved proteins with
complex alpha/beta domains. In contrast, thermosome substrates comprise a group
of faster-evolving proteins and contain a much wider range of different domain
folds, including small all-alpha and all-beta modules, and a greater number of
large multidomain proteins. Thus, the group II chaperonins may have facilitated
the evolution of the highly complex proteomes characteristic of eukaryotic
cells. It is now well understood that, although proteins fold spontaneously (in a
thermodynamic sense), many nevertheless require the assistance of helpers called
molecular chaperones to reach their correct and active folded state in living
cells. This is because the pathways of protein folding are full of traps for the
unwary: the forces that drive proteins into their folded states can also drive
them into insoluble aggregates, and, particularly when cells are stressed, this
can lead, without prevention or correction, to cell death. The chaperonins are a
family of molecular chaperones, practically ubiquitous in all living organisms,
which possess a remarkable structure and mechanism of action. They act as
oboxes in which proteins can fold, isolated from their environment and from
other partners with which they might, with potentially deleterious consequences,
interact. The opening and closing of these boxes is timed by the binding and
hydrolysis of ATP. The chaperonins which are found in bacteria are extremely
well characterized, and, although those found in archaea (also known as
thermosomes) and eukaryotes have received less attention, our understanding of
these proteins is constantly improving. This short review will summarize what we
know about chaperonin function in the cell from studies on the archaeal
chaperonins, and show how recent work is improving our understanding of this
essential class of molecular chaperones. BACKGROUND: Chaperonins are important in living systems because they play a role
in the folding of proteins. Earlier comprehensive analyses identified substrate
proteins for which folding requires the chaperonin GroEL/GroES (GroE) in
Escherichia coli, and they revealed that many chaperonin substrates are
metabolic enzymes. This result implies the importance of chaperonins in
metabolism. However, the relationship between chaperonins and metabolism is
still unclear.
RESULTS: We investigated the distribution of chaperonin substrate enzymes in the
metabolic network using network analysis techniques as a first step towards
revealing this relationship, and found that as chaperonin requirement increases,
substrate enzymes are more laterally distributed in the metabolic. In addition,
comparative genome analysis showed that the chaperonin-dependent substrates were
less conserved, suggesting that these substrates were acquired later on in
evolutionary history.
CONCLUSIONS: This result implies the expansion of metabolic networks due to this
chaperonin, and it supports the existing hypothesis of acceleration of evolution
by chaperonins. The distribution of chaperonin substrate enzymes in the
metabolic network is inexplicable because it does not seem to be associated with
individual protein features such as protein abundance, which has been observed
characteristically in chaperonin substrates in previous works. However, it
becomes clear by considering this expansion process due to chaperonin. This
finding provides new insights into metabolic evolution and the roles of
chaperonins in living systems. Chaperonins are universally conserved molecular machines that facilitate the
proper -folding of nascent and partially folded polypeptides into their
respective three-dimensional structures. These multimeric protein complexes
utilize the energy derived from ATP hydrolysis to fuel a protein-folding
mechanism that consists of multiple rounds of substrate binding, encapsulation,
and eventual expulsion back into the cytosolic environment. In this portion of
the chapter, the structure and function of group I and group II chaperonins are
discussed. Furthermore, the general mechanism of chaperonin-mediated protein
folding is addressed in addition to illustrating how viral phages such as
Lambda, T4, and RB49 exploit the host machinery for the proper folding of viral
gene products. Lastly, the phiEL chaperonin from phage EL is revealed to be the
first virally encoded chaperonin and is proposed to function independently of
the host chaperonin machinery. The molecular architecture of the phiEL
chaperonin, coupled with its unique functional abilities, renders its
characterization a challenge and further highlights its novelty as a potentially
whole new class of chaperonins. Chaperonins are a class of molecular chaperones that assemble into a large
double ring architecture with each ring constituting seven to nine subunits and
enclosing a cavity for substrate encapsulation. The well-studied Escherichia
coli chaperonin GroEL binds non-native substrates and encapsulates them in the
cavity thereby sequestering the substrates from unfavorable conditions and
allowing the substrates to fold. Using this mechanism, GroEL assists folding of
about 10-15 % of cellular proteins. Surprisingly, about 30 % of the bacteria
express multiple chaperonin genes. The presence of multiple chaperonins raises
questions on whether they increase general chaperoning ability in the cell or
have developed specific novel cellular roles. Although the latter view is widely
supported, evidence for the former is beginning to appear. Some of these
chaperonins can functionally replace GroEL in E. coli and are generally
indispensable, while others are ineffective and likewise are dispensable.
Additionally, moonlighting functions for several chaperonins have been
demonstrated, indicating a functional diversity among the chaperonins.
Furthermore, proteomic studies have identified diverse substrate pools for
multiple chaperonins. We review the current perception on multiple chaperonins
and their physiological and functional specificities. In review provides information about the function oft the body of chaperones and
their role in the development of pathological processes,
including--atherosclerosis and coronary heart disease. Marked comminications
systems chaperones to the immune and endocrine systems, and inflammation. Chaperonins are protein-folding machinery found in all cellular life. Chaperonin
genes have been documented within a few viruses, yet, surprisingly, analysis of
metagenome sequence data indicated that chaperonin-carrying viruses are common
and geographically widespread in marine ecosystems. Also unexpected was the
discovery of viral chaperonin sequences related to thermosome proteins of
archaea, indicating the presence of virioplankton populations infecting marine
archaeal hosts. Virioplankton large subunit chaperonin sequences (GroELs) were
divergent from bacterial sequences, indicating that viruses have carried this
gene over long evolutionary time. Analysis of viral metagenome contigs indicated
that: the order of large and small subunit genes was linked to the phylogeny of
GroEL; both lytic and temperate phages may carry group I chaperonin genes; and
viruses carrying a GroEL gene likely have large double-stranded DNA (dsDNA)
genomes (>70 kb). Given these connections, it is likely that chaperonins are
critical to the biology and ecology of virioplankton populations that carry
these genes. Moreover, these discoveries raise the intriguing possibility that
viral chaperonins may more broadly alter the structure and function of viral and
cellular proteins in infected host cells. Chaperonins are a subclass of molecular chaperones that assist cellular proteins
to fold and assemble into their native shape. Much work has been done on Type I
chaperonins, which has elucidated their elegant mechanism. Some debate remains
about the details in these mechanisms, but nonetheless the roles of these in
helping protein folding have been understood in great depth. In this review we
discuss the known functions of atypical Type I chaperonins, highlighting
evolutionary aspects that might lead chaperonins to perform alternate functions. Molecular chaperones promote the correct folding of proteins in
aggregation-prone cellular environments by stabilizing nascent polypeptide
chains and providing appropriate folding conditions. Prefoldins (PFDs) are
molecular chaperones found in archaea and eukaryotes, generally characterized by
a unique jellyfish-like hexameric structure consisting of a rigid beta-barrel
backbone with protruding flexible coiled-coils. Unlike eukaryotic PFDs that
mainly interact with cytoskeletal components, archaeal PFDs can stabilize a wide
range of substrates; such versatility reflects PFD's role as a key element in
archaeal chaperone systems, which often lack general nascent-chain binding
chaperone components such as Hsp70. While archaeal PFDs mainly exist as
hexameric complexes, their structural diversity ranges from tetramers to
filamentous oligomers. PFDs bind and stabilize nonnative proteins using varying
numbers of coiled-coils, and subsequently transfer the substrate to a group II
chaperonin (CPN) for refolding. The distinct structure and specific function of
archaeal PFDs have been exploited for a broad range of applications in
biotechnology; furthermore, a filament-forming variant of PFD has been used to
fabricate oscale architectures of defined shapes, demonstrating archaeal
PFDs' potential applicability in otechnology. Molecular chaperones are key players in proteostasis, the balance between
protein synthesis, folding, assembly and degradation. They are helped by a
plethora of cofactors termed cochaperones, which direct chaperones towards any
of these different, sometime opposite pathways. One of these is prefoldin (PFD),
present in eukaryotes and in archaea, a heterohexamer whose best known role is
the assistance to group II chaperonins (the Hsp60 chaperones found in archaea
and the eukaryotic cytosolic) in the folding of proteins in the cytosol, in
particular cytoskeletal proteins. However, over the last years it has become
evident a more complex role for this cochaperone, as it can adopt different
oligomeric structures, form complexes with other proteins and be involved in
many other processes, both in the cytosol and in the nucleus, different from
folding. This review intends to describe the structure and the many functions of
this interesting macromolecular complex. |
Can FTO promote pancreatic cancer development? | No, the m6A demethylase FTO suppresses pancreatic cancer tumorigenesis. | Pancreatic cancer is the deadliest maligcy of the digestive system and is the
seventh most common cause of cancer-related deaths worldwide. The incidence and
mortality of pancreatic cancer continue to increase, and its 5-year survival
rate remains the lowest among all cancers. N6-methyladenine (m6A) is the most
abundant reversible RNA modification in various eukaryotic messenger and long
noncoding RNAs and plays crucial roles in the occurrence and development of
cancers. However, the role of m6A in pancreatic cancer remains unclear. The
present study aimed to explore the role of m6A and its regulators in pancreatic
cancer and assess its underlying molecular mechanism associated with pancreatic
cancer cell proliferation, invasion, and metastasis. Reduced expression of the
m6A demethylase, fat mass and obesity-associated protein (FTO), was responsible
for the high levels of m6A RNA modification in pancreatic cancer. Moreover, FTO
demethylated the m6A modification of praja ring finger ubiquitin ligase 2
(PJA2), thereby reducing its mRNA decay, suppressing Wnt signaling, and
ultimately restraining the proliferation, invasion, and metastasis of pancreatic
cancer cells. Altogether, this study describes new, potential molecular
therapeutic targets for pancreatic cancer that could pave the way to improve
patient outcome. |
Which disorder is caused by biallelic mutations in G-Protein coupled receptor kinase 1 (GRK1)? | Biallelic mutations in G-Protein coupled receptor kinase 1 (GRK1) cause Oguchi disease, a rare subtype of congenital stationary night blindness (CSNB). | Author information:
(1)Division of Molecular Medicine, Leeds Institute of Medical Research,
University of Leeds, Leeds, UK.
(2)School of Molecular and Cellular Biology, University of Leeds, Leeds, UK.
(3)Division of Evolution and Genomic Sciences, School of Biological Sciences,
Faculty of Biology, Medicines and Health, University of Manchester, Manchester,
UK.
(4)National Institute of Sensory Organs, National Hospital Organization Tokyo
Medical Centre, Tokyo, Japan.
(5)Moorfields Eye Hospital, London, UK.
(6)UCL Institute of Ophthalmology, London, UK.
(7)Keio University School of Medicine, Tokyo, Japan.
(8)Ghent University, Ghent, Belgium.
(9)Division of Genetic Medicine, Centre Hospitalier Universitaire Vaudois
(CHUV), University of Lausanne, Lausanne, Switzerland.
(10)The Jikei University School of Medicine, Tokyo, Japan.
(11)Mie University Graduate School of Medicine, Mie, Japan.
(12)Department of Genetics, Faculty of Science, Hazara University Mansehra,
Dhodial, Pakistan.
(13)Clinical Research Center, Institute of Molecular and Clinical Ophthalmology
Basel (IOB), Basel, Switzerland.
(14)School of Biomedical Sciences, University of Leeds, Leeds, UK.
(15)Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
(16)St Thomas's Hospital, London, UK.
(17)Department of Ophthalmology, Great Ormond Street Hospital, London, UK.
(18)Department of Genetics and Genome Biology, University of Leicester,
Leicester, UK.
(19)Department of Ophthalmology, University Hospital Basel, Basel, Switzerland.
(20)Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.
(21)Manchester Centre for Genomic Medicine, Saint Mary's Hospital, Manchester
University NHS Foundation Trust, Manchester, UK.
(22)Leeds Teaching Hospitals NHS Trust, St James' University Hospital, Leeds,
UK.
(23)School of Physics and Astronomy, University of Leeds, Leeds, UK. |
Which disease is treated with Tebentafusp? | Tebentafusp is used for treatment of Metastatic Uveal Melanoma. | Uveal melanoma (UM) is the most common primary intraocular maligcy in adults.
UMs are usually initiated by a mutation in GNAQ or GNA11, unlike cutaneous
melanomas, which usually harbour a BRAF or NRAS mutation. The annual incidence
in Europe and the USA is ~6 per million population per year. Risk factors
include fair skin, light-coloured eyes, congenital ocular melanocytosis, ocular
melanocytoma and the BAP1-tumour predisposition syndrome. Ocular treatment aims
at preserving the eye and useful vision and, if possible, preventing metastases.
Enucleation has largely been superseded by various forms of radiotherapy,
phototherapy and local tumour resection, often administered in combination.
Ocular outcomes are best with small tumours not extending close to the optic
disc and/or fovea. Almost 50% of patients develop metastatic disease, which
usually involves the liver, and is usually fatal within 1 year. Although UM
metastases are less responsive than cutaneous melanoma to chemotherapy or immune
checkpoint inhibitors, encouraging results have been reported with partial
hepatectomy for solitary metastases, with percutaneous hepatic perfusion with
melphalan or with tebentafusp. Better insight into tumour immunology and
metabolism may lead to new treatments. PURPOSE OF REVIEW: Uveal melanoma is a distinct subtype of melanoma
characterized by a unique biology and divergent response to immune therapies. In
this review, we will discuss our current understanding of the pathophysiology of
uveal melanoma, systemic treatment options for advanced disease, and potential
future therapeutic directions.
RECENT FINDINGS: Although treatment with single-agent checkpoint blockade has
been generally disappointing, the results of combined checkpoint blockade are
modestly more promising. Several alternative systemic therapeutic approaches
have been or are currently being investigated, including two agents that have
been taken into registration-intent clinical trials: tebentafusp, a T cell
redirecting agent, and IDE196, an oral protein kinase C inhibitor. Treatment of
advanced uveal melanoma remains challenging, however, encouraging results from
novel agents offer hope for improvement in the near future. PURPOSE: Tebentafusp is a first-in-class bispecific fusion protein designed to
target gp100 (a melanoma-associated antigen) through a high affinity T-cell
receptor (TCR) binding domain and an anti-CD3 T-cell engaging domain, which
redirects T cells to kill gp100-expressing tumor cells. Here, we report a
multicenter phase I/II trial of tebentafusp in metastatic melanoma (NCT01211262)
focusing on the mechanism of action of tebentafusp.
PATIENTS AND METHODS: Eighty-four patients with advanced melanoma received
tebentafusp. Treatment efficacy, treatment-related adverse events, and biomarker
assessments were performed for blood-derived and tumor biopsy samples obtained
at baseline and on-treatment.
RESULTS: Tebentafusp was generally well-tolerated and active in both patients
with metastatic uveal melanoma and patients with metastatic cutaneous melanoma.
A 1-year overall survival rate of 65% was achieved for both patient cohorts.
On-treatment cytokine measurements were consistent with the induction of IFNγ
pathway-related markers in the periphery and tumor. Notably, tebentafusp induced
an increase in serum CXCL10 (a T-cell attractant) and a reduction in circulating
CXCR3+ CD8+ T cells together with an increase in cytotoxic T cells in the tumor
microenvironment. Furthermore, increased serum CXCL10 or the appearance of rash
(likely due to cytotoxic T cells targeting gp100-expressing skin melanocytes)
showed a positive association with patient survival.
CONCLUSIONS: These data suggest that redirecting T cells using a gp100-targeting
TCR/anti-CD3 bispecific fusion protein may provide benefit to patients with
metastatic melanoma. Furthermore, the activity observed in these two molecularly
disparate melanoma classes hints at the broad therapeutic potential of
tebentafusp. A bispecific fusion protein designed to redirect T cells toward a
melanoma-associated antigen helped prolong survival among patients with an
aggressive form of eye cancer. If approved, tebentafusp could become the
standard of care for metastatic uveal melanoma-but only for those patients with
a particular HLA allele. Author information:
(1)From Mount Vernon Cancer Centre, Northwood (P.N.), the Clatterbridge Cancer
Centre NHS Foundation Trust, Wirral (J.J.S.), the University of Liverpool,
Liverpool (J.J.S.), and Immunocore, Abingdon (S.E.A., C.H., H.G.) - all in the
United Kingdom; the Department of Dermatology and the National Center for Tumor
Diseases, University Hospital Heidelberg, Heidelberg (J.C.H.), the Department of
Dermatology and Allergy, University Hospital, Ludwig Maximilian University of
Munich, Munich (M.S.), the Department of Hematology and Oncology,
Charité-Comprehensive Cancer Center (S.O.), Berlin, and the Department of
Dermatology and the Center for Integrated Oncology, University Hospital Cologne,
Cologne (C.M.) - all in Germany; Maria Sklodowska-Curie National Research
Institute of Oncology, Warsaw, Poland (P.R.); Institut Roi Albert II des
Cliniques Universitaires Saint-Luc and Université Catholique de Louvain,
Brussels (J.-F.B.); Princess Margaret Cancer Centre, Toronto (M.O.B.);
Massachusetts General Hospital Cancer Center, Boston (R.J.S.); the Department of
Dermatology, University Hospital of Zurich, Zurich, Switzerland (R.D.); Hillman
Cancer Center, University of Pittsburgh Medical Center, Pittsburgh (J.M.K.);
Sidney Kimmel Cancer Center, Thomas Jefferson University Hospital, Philadelphia
(M.O.); Kinghorn Cancer Centre, Saint Vincent's Hospital, Darlinghurst, NSW,
Australia (A.M.J.); Memorial Sloan Kettering Cancer Center (A.N.S.) and Irving
Medical Center, Columbia University (R.D.C.) - both in New York; Institut
d'Investigació Biomèdica de Bellvitge-Centro de Investigación Biomédica en Red
de Oncología, Institut Català d'Oncologia, Barcelona (J.M.P.); University of
Iowa Hospitals and Clinics, Iowa City (M.M.); Duke University, Durham, NC
(A.K.S.S.); Earle A. Chiles Research Institute, Providence Cancer Institute,
Portland, OR (B.C.); N.N. Blokhin Cancer Research Center, Moscow (L.D.); Centre
Antoine Lacassagne, Nice (L.G.) and Institut Curie, Paris Sciences and Letters
Research University, Paris (S.P.-N.) - both in France; Winship Cancer Institute,
Emory University, Atlanta (M.Y.); and the Angeles Clinic and Research Institute,
a Cedars-Sinai Affiliate, Los Angeles (O.H.). Uveal melanoma is a rare neoplasm with poor prognosis in the metastatic setting.
Unlike cutaneous melanoma, treatment with kinase inhibitors or immune checkpoint
inhibitors is not effective. Glycoprotein 100 (Gp-100) is a protein highly
expressed in melanocytes and melanoma that has recently been effectively
targeted by tebentafusp, a first-in-class bispecific protein of the
immune-mobilizing monoclonal T cell receptors against cancer (ImmTACs) family.
Tebentafusp targets tumor cells that express a peptide of Gp-100 presented by
HLA*A0201, creating an immune synapse that kills targeted tumor cells. Recently,
a randomized phase III trial reported an overall survival benefit for
tebentafusp in patients with untreated metastatic uveal melanoma. The aim of
this comprehensive review is to summarize evidence of Gp-100 as a therapeutic
target in melanoma, and the preclinical and clinical development of tebentafusp
as a novel therapeutic strategy for patients with uveal melanoma. |
Is Lysozyme abundant in human tears? | Yes,
lysozyme is the most prevalent protein in tear fluid. | We studied the behaviour of three lipid tear products, commercialised by the
same brand, as Langmuir films at the air/liquid interface to simulate the ocular
environment. No significant differences were observed in the surface behaviour
of two of them disclosing the same composition, but commercialised for different
applications. The interaction of several subphases, namely sodium chloride,
glucose, albumin and lysozyme present in the natural tear, with the lipid films
was assessed at room temperature and the temperature of human tear using surface
pressure-area isotherms and elastic modulus plots. There is a notable influence
of sodium chloride and the proteins albumin and lysozyme on the surface
pressure-area isotherm of the lipid Langmuir films. Albumin shifted this
isotherm to lower areas while an opposite shift was caused by lysozyme. These
studies could be useful for the formulation of new lipid-containing artificial
tears, and for increasing the confidence of the customers in commercial eye care
formulations. Lysozyme (Lyz) is a naturally occurring enzyme that operates against
Gram-positive bacteria and leads to cell death. This antimicrobial enzyme forms
the part of the innate defense system of nearly all animals and exists in their
somatic discharges such as milk, tears, saliva and urine. Increased Lyz level in
serum is an important indication of several severe diseases and so, precise
diagnosis of Lyz is an urgent need in biosensing assays. Up to know, various
traditional and modern techniques have been introduced for Lyz determination.
Although the traditional methods suffer from some significant limitations such
as time-consuming, arduous, biochemical screening, bacterial colony isolation,
selective enrichment and requiring sophisticated instrumentation or isotope
labeling, some new modern approaches like aptamer-based biosensors (aptasensors)
and quantum dot (QD) omaterials are the main goal in Lyz detection.
Electrochemical and optical sensors have been highlighted because of their
adaptability and capability to decrease the drawbacks of common methods. Using
an aptamer-based biosensor, sensor selectivity is enhanced due to the specific
recognition of the analyte. Thereby, in this review article, the recent advances
and achievements in electrochemical and optical aptasensing detection of Lyz
based on different QD omaterials and detection methods have been discussed in
detail. PURPOSE: To evaluate the concentration of tear lysozyme in individuals with
Sjogren´s syndrome, meibomian gland dysfunction, and non-dry-eye disease.
METHODS: Ninety subjects were recruited for this study, including 30 with
Sjogren´s syndrome, 30 with meibomian gland dysfunction, and 30 with non-dry-eye
disease. All subjects were referred to participate in the study based on a "dry
eye" investigation. They underwent a complete ocular surface ophthalmic
examination encompassing ocular surface disease index, biomicroscopy, tear
break-up time, Schirmer test type I, conjunctival vital staining with
fluorescein and lissamine green, tear lysozyme concentration, and impression
cytology.
RESULTS: Clinical tests yielded the following results: ocular surface disease
index Sjogren´s syndrome: 64.5 ± 22.6 meibomian gland dysfunction: 43.5 ± 21.4,
non-dry-eye disease: 6.7 ± 4.3 (p=0.02 between groups); Schirmer I test (mm/5
min): Sjogren´s syndrome: 4.95 ± 2.25, meibomian gland dysfunction: 13.28 ±
1.53, non-dry-eye disease 13.70 ± 1.39 (p<0.01 Sjogren´s syndrome vs.
non-dry-eye disease and p<0.01 meibomian gland dysfunction vs. non-dry-eye
disease); tear break-up time (seconds): Sjogren´s syndrome: 3.97 ± 1.47,
meibomian gland dysfunction: 3.95 ± 0.86, non-dry-eye disease: 7.25 ± 1.90
(p<0.01 Sjogren´s syndrome vs. non-dry-eye disease and p<0.01 meibomian gland
dysfunction vs. non-dry-eye disease); Lissamine green score: Sjogren´s
syndrome-dry-eye: 6.18 ± 2.14, meibomian gland dysfunction-dry-eye: 5.27 ± 1.27,
non-dry-eye disease: 1.52 ± 0.97 (p<0.01 Sjogren´s syndrome vs. non-dry-eye
disease and p<0.01 meibomian gland dysfunction vs. non-dry-eye disease);
impression cytology score: Sjogren´s syndrome: 1.88 ± 0.92, meibomian gland
dysfunction: 1.67 ± 0.56, non-dry-eye: 0.45 ± 0.44 (p<0.01 Sjogren´s syndrome
vs. non-dry-eye disease and p<0.01 meibomian gland dysfunction vs. non-dry-eye
disease) and; tear lysozyme concentration (µg/mL): Sjogren´s syndrome: 751.25 ±
244.73, meibomian gland dysfunction: 1423.67 ± 182.75, non-dry-eye disease:
1409.90 ± 188.21 (p<0.01 Sjogren´s syndrome vs. non-dry-eye disease and p<0.01
Sjogren´s syndrome vs. meibomian gland dysfunction).
CONCLUSION: The concentration of lysozyme in the tears was lower in Sjögren's
syndrome patients than in meibomian gland dysfunction and non-dry-eye disease
groups. Hence, the lacrimal lysozyme could be considered as a simple,
non-invasive, and economical biomarker to differentiate between Sjögren's
syndrome dry eye disease and meibomian gland dysfunction dry eye disease. |
What is Neuromedin U (NmU) | Neuromedin U (NmU) is a highly conserved neuropeptide and has multiple physiological and pathophysiological roles detected, ranging from smooth muscle contraction, feeding, energy balance to tumorigenesis, stress responses, and inflammation. | Neuromedin U (NMU) is a neuropeptide with potent activity on smooth muscle which
was isolated first from porcine spinal cord and later from other species. It is
widely distributed in the gut and central nervous system. Peripheral activities
of NMU include stimulation of smooth muscle, increase of blood pressure,
alteration of ion transport in the gut, control of local blood flow and
regulation of adrenocortical function. An NMU receptor has not been molecularly
identified. Here we show that the previously described orphan G-protein-coupled
receptor FM-3 (ref. 15) and a newly discovered one (FM-4) are cognate receptors
for NMU. FM-3, designated NMU1R, is abundantly expressed in peripheral tissues
whereas FM-4, designated NMU2R, is expressed in specific regions of the brain.
NMU is expressed in the ventromedial hypothalamus in the rat brain, and its
level is significantly reduced following fasting. Intracerebroventricular
administration of NMU markedly suppresses food intake in rats. These findings
provide a molecular basis for the biochemical activities of NMU and may indicate
that NMU is involved in the central control of feeding. Neuromedin U (NMU) is a brain-gut peptide whose peripheral activities are
well-understood but whose central actions have yet to be clarified. The recent
identification of two NMU receptors in rat brain has provided a springboard for
further investigation into its role in the central nervous system.
Intracerebroventricular administration of NMU to free-feeding rats decreased
food intake and body weight. Conversely, NMU increased gross locomotor activity,
body temperature, and heat production. NMU, a potent endogenous anorectic
peptide, serves as a catabolic signaling molecule in the brain. Further
investigation of the biochemical and physiological functions of NMU will help
our better understanding of the mechanisms of energy homeostasis. Neuromedin U (NMU) is a hypothalamic peptide that has been recently found to
reduce food intake, but few is known about its other functions in the central
nervous system. We here studied behavioral activities induced by an
intracerebroventricular (ICV) administration of NMU in rats and mice. NMU
increased gross locomotor activity, face washing behavior, and grooming.
NMU-induced stress response was significantly abolished by pretreatment with an
antagonist of corticotropin-releasing hormone (CRH), alpha-helical CRH (9-41)
(alpha-hCRH), or anti-CRH IgG. NMU did not induce locomotor activity in CRH
knockout mice. NMU that interacts anatomically and/or functionally with the CRH
system is a novel physiological regulator of stress response. Neuromedin U (NMU) is a brain-gut peptide, which peripherally stimulates smooth
muscle, increases of blood pressure, alters ion transport in the gut, controls
local blood flow, and regulates adrenocortical function. Although
intracerebroventricular (i.c.v.) administration of NMU is known to decrease food
intake and body weight, little is known about its effect on other physiological
functions. We examined the effects of i.c.v. administration of NMU on mean
arterial pressure (MAP), heart rate (HR), and plasma norepinephrine in conscious
rats. Neuromedin U (0.05 and 0.5 nmol) provoked an increase in MAP (93.8 +/- 0.5
to 123.5 +/- 1.7 and 94.7 +/- 0.8 to 132.7 +/- 3.0 mm Hg, respectively) and HR
(334.9 +/- 6.0 to 494.1 +/- 6.9 and 346.3 +/- 3.3 to 475.1 +/- 8.9 beats/min,
respectively). In contrast, plasma norepinephrine increased only with a high
dose of neuromedin U. Intravenously administered NMU (0.5 nmol) elicited a small
and short lasting increase in MAP, compared to that by i.c.v. NMU. These results
indicate that central neuromedin U regulates sympathetic nervous system activity
and affects cardiovascular function. The neuropeptide neuromedin U (NMU) has been shown to have significant effects
on cardiovascular, gastrointestinal and CNS functions. The peptide was first
isolated from the porcine spinal cord and later shown to be present in spinal
cords of other species. Little is known about the distribution of neuromedin U
receptors (NMURs) in the spinal cord and the spinal action of the peptide. Here
we report on the expression of NMURs and a potential role in nociception in the
rat spinal cord using a combination of behavioral and electrophysiological
studies. Receptor autoradiography showed that NMU-23 binding was restricted to
the superficial layers of spinal cord, a region known to be involved in the
control of nociception. In situ hybridization analysis indicated the mRNA of
NMUR2 was located in the same region (laminae I and IIo) as NMU-23 binding,
while the mRNA for NMU receptor 1 was observed in a subpopulation of small
diameter neurons of dorsal root ganglia. Intrathecal (i.t.) administration of
neuromedin U-23 (0.4-4.0 nmol/10 microl) dose-dependently decreased both the
mechanical threshold to von Frey hair stimulation and the withdrawal latency to
a noxious thermal stimulus. Mechanical allodynia was observed between 10 and 120
min, peaking at 30 min and heat hyperalgesia was observed 10-30 min after i.t.
administration of NMU-23. A similar mechanical allodynia was also observed
following i.t. administration of NMU-8 (0.4-4 nmol/10 microl). A significant
enhancement of the excitability of flexor reflex was induced by intrathecal
administration of NMU-23 (4 nmol/10 microl). Evoked responses to touch and pinch
stimuli were increased by 439+/-94% and 188+/-36% (P<0.01, n=6) respectively.
The behavioral and electrophysiological data demonstrate, for the first time, a
pro-nociceptive action of NMU. The restricted distribution of NMU receptors to a
region of the spinal cord involved in nociception suggests that this peptide
receptor system may play a role in nociception. OBJECTIVES: Neuromedin U (NmU) is a neuropeptide with anorexigenic activity. Two
receptor subtypes (NmUR1 and NmUR2) confer the effects of NmU on target cells.
We have recently demonstrated that NmU reduces insulin secretion from isolated
pancreatic islets. Aim of our current study is to investigate the role of
somatostatin at mediating the effects of NmU on insulin secretion.
METHODS: Expression of NmU in the pancreas was detected by immunohistochemistry.
Insulin and somatostatin secretion from in situ perfused rat pancreas and
isolated pancreatic islets was measured by radioimmunoassay. The paracrine
effects of somatostatin within pancreatic islets were blocked by
cyclosomatostatin, a somatostatin receptor antagonist.
RESULTS: Receptor subtype NmUR1, but not NmUR2, was expressed in the endocrine
pancreas, predomitly in the periphery. Neuromedin U reduced insulin secretion
from in situ perfused rat pancreas and stimulated somatostatin secretion from
isolated pancreatic islets. Neuromedin U stimulated somatostatin secretion at
both physiological and supraphysiological glucose concentrations.
Cyclosomatostatin increased insulin secretion and reduced NmU-induced inhibition
of insulin secretion.
CONCLUSIONS: Neuromedin U reduces insulin and increases somatostatin secretion.
Blockade of somatostatin action abolishes the inhibition of insulin secretion by
NmU. The results of the study suggest that somatostatin mediates the inhibitory
action of NmU on insulin secretion. Neuromedin U (NMU) and neuromedin S (NMS) are structurally related neuropeptides
that have been reported to modulate energy homeostasis. Pharmacological data
have shown that NMU and NMS inhibit food intake when administered centrally and
that NMU increases energy expenditure. Additionally, NMU-deficient mice develop
obesity, whereas transgenic mice overexpressing NMU are lean and hypophagic. Two
high-affinity NMU/NMS receptors, NMUR1 and NMUR2, have been identified. NMUR1 is
predomitly expressed in the periphery, whereas NMUR2 is predomitly
expressed in the brain, suggesting that the effects of centrally administered
NMU and NMS are mediated by NMUR2. To evaluate the role of NMUR2 in the
regulation of energy homeostasis, we characterized NMUR2-deficient (Nmur2(-/-))
mice. Nmur2(-/-) mice exhibited a modest resistance to diet-induced obesity that
was at least in part due to reduced food intake. Acute central administration of
NMU and NMS reduced food intake in wild-type but not in Nmur2(-/-) mice. The
effects on activity and core temperature induced by centrally administered NMU
were also absent in Nmur2(-/-) mice. Moreover, chronic central administration of
NMU and NMS evoked significant reductions in body weight and sustained
reductions in food intake in mice. In contrast, Nmur2(-/-) mice were largely
resistant to these effects. Collectively, these data demonstrate that the
anorectic and weight-reducing actions of centrally administered NMU and NMS are
mediated predomitly by NMUR2, suggesting that NMUR2-selective agonists may be
useful for the treatment of obesity. BACKGROUND: Neuromedin U (NmU) belongs to the neuromedin family, comprising a
series of neuropeptides involved in the gut-brain axis and including neuromedins
B and C (bombesin-like), K (neurokinin B), L (neurokinin A or neurotensin), N,
S, and U.
CONTENT: Although initially isolated from porcine spinal cord on the basis of
their ability to induce uterine smooth muscle contraction, these peptides have
now been found to be expressed in several different tissues and have been
ascribed numerous functions, from appetite regulation and energy balance control
to muscle contraction and tumor progression. NmU has been detected in several
species to date, particularly in mammals (pig, rat, rabbit, dog, guinea pig,
human), but also in amphibian, avian, and fish species. The NmU sequence is
highly conserved across different species, indicating that this peptide is
ancient and plays an important biological role. Here, we summarize the main
structural and functional characteristics of NmU and describe its many roles,
highlighting the jack-of-all-trades nature of this neuropeptide.
SUMMARY: NmU involvement in key processes has outlined the possibility that this
neuropeptide could be a novel target for the treatment of obesity and cancer,
among other disorders. Although the potential for NmU as a therapeutic target is
obvious, the multiple functions of this molecule should be taken into account
when designing an approach to targeting NmU and/or its receptors. Neuromedin U (NMU), a neuropeptide isolated from porcine spinal cord and named
because of its activity as a rat uterus smooth muscle contraction inducer, is
emerging as a new player in the tumorigenesis and/or metastasis of many types of
cancers. Expressed in a variety of tissues, NMU has been shown to possess many
important activities in the central nervous system as well as on the periphery.
Along with the main structural and functional features of NMU and its currently
known receptors, we summarized a growing number of recently published data from
different tissues and cells that associate NMU activity with cancer development
and progression. We ask if, based on current reports, NMU can be included as a
marker of these processes and/or considered as a therapeutic target. Neuromedin U (NMU) is a highly conserved neuropeptide that has been implicated
in the stress response. To better understand how it influences various aspects
of the stress response, we studied the effects of intracerebroventricular NMU-8
administration on stress-related behavior and activity of the
hypothalamus-pituitary-adrenal (HPA) axis in male C57BL/6J mice. We investigated
these NMU-8 effects when mice remained in their home cage and when they were
challenged by exposure to forced swim stress. NMU-8 administration resulted in
increased grooming behavior in mice that remained in their home cage and in a
significant increase in c-Fos immunoreactivity in the paraventricular
hypothalamus (PVH) and arcuate nucleus (ARC). Surprisingly, NMU-8 administration
significantly decreased plasma corticosterone concentrations. Furthermore, NMU-8
administration increased immobility in the forced swim test in both naïve mice
and mice that were previously exposed to swim stress. The effect of NMU-8 on
c-Fos immunoreactivity in the PVH was dependent on previous exposure to swim
stress given that we observed no significant changes in mice exposed for the
first time to swim stress. In contrast, in the ARC we observed a significant
increase in c-Fos immunoreactivity regardless of previous stress exposure.
Interestingly, NMU-8 administration also significantly decreased plasma
corticosterone concentrations in mice that were exposed to single forced swim
stress, while this effect was no longer observed when mice were exposed to
forced swim stress for a second time. Taken together, our data indicate that
NMU-8 regulates stress responsiveness and suggests that its effects depend on
previous stress exposure. Asthma is a major inflammatory airway disease with high incidence and mortality
rates. The Global Initiative for Asthma released a report called 'The Global
Burden of Asthma' in 2004. However, the specific pathogenesis of asthma remains
unclear. An increasing number of studies have demonstrated that neuromedin U
(NMU) plays a pleiotropic role in the pathogenesis of asthma. NMU is a highly
structurally conserved neuropeptide that was first purified from porcine spinal
cord and named for its contractile effect on the rat uterus. NMU amplifies type
2 innate lymphoid cell (ILC2)-driven allergic lung inflammation. The NMU
receptors (NMURs), designated as NMUR1 and NMUR2, belong to the G
protein-coupled receptor family. NMUR1 has also been found in immune cells,
including ILC2s, mast cells and eosinophils. In view of the important roles of
NMU in the pathogenesis of asthma, the present review evaluates the potential
mechanisms underlying the impact of NMU on asthma and its association with
asthma therapy. BACKGROUND: Neuromedin U (NMU) is a neuropeptide belonging to the neuromedin
family. Recently, significant associations between NMU and several cancers have
been reported. However, no studies have examined the association between NMU and
hepatocellular carcinoma (HCC). The purpose of this study was to examine the
role of NMU in HCC.
METHODS: An enzyme-linked immunosorbent assay was used to measure the level of
NMU protein in the sera of patients with hepatic hemangioma and HCC. NMU and
cytokine mRNA expression was assessed in HCC samples via RT-qPCR. A tissue
microarray consisting of 228 HCC peri- and intra-tumor tissues was used to
detect NMU expression via immunohistochemical analysis. The association between
NMU expression and overall survival (OS) and disease-free survival (DFS) was
analyzed by Kaplan-Meier curves, the log-rank test, and Cox proportional hazard
model.
RESULTS: The level of NMU protein was increased in the sera of HCC patients
(p = 0.006). NMU was expressed in intercellular space, rather than in
hepatocytes or HCC cells. The prognosis of HCC patients with high NMU expression
in peri-tumor tissue was significantly poorer than that of patients with low NMU
expression (OS: p = 0.002, DFS: p = 0.033). Peri-tumor NMU expression was also a
significant independent prognostic factor for OS (hazard ratio: 1.541, 95%
confidence interval: 1.092-2.175, p = 0.014). The level of NMU expression was
positively associated with M2 macrophage percentage and the levels of type-2
inflammatory cytokines in HCC tissue.
CONCLUSIONS: NMU may serve as a novel prognostic biomarker for HCC patients,
although further validation is needed in the future. The activation of M2
macrophages and a type-2 inflammatory response may involve in the role of NMU in
patients with HCC. Neuromedin U (NMU) is a bioactive neuropeptide, highly distributed in the
gastrointestinal tract and the central nervous system. NMU has various
physiological functions related to feeding behavior, energy metabolism, stress
responses, circadian rhythmicity and inflammation. Recently, several reports
indicate that the central NMU system plays an important role in the reward
systems in the brain. However, the underlying molecular mechanisms are not yet
fully defined. In this study, we found that some of cocaine-induced c-Fos
immunoreactive cells were co-localized with NMU in the nucleus accumbens (NAc),
caudate putamen (CPu), and basolateral amygdala (BLA), which are key brain
regions associated with the brain reward system, in wild type mice. Whereas, a
treatment with cocaine did not influence the kinetics of NMU or NMU receptors
mRNA expression in these brain regions, and NMU-knockout mice did not show any
higher preference for cocaine compared with their control mice. These results
indicate that cocaine has some effect on NMU expressing neurons related to the
brain reward system, and this suggests NMU system may have a role on the brain
reward systems activated by cocaine. |
Is FTY720 FDA approved? | Yes, FTY720 was approved by the US Food and Drug Administration (FDA) in 2010. | FTY720 (Fingolimod) is a known sphingosine-1-phosphate (S1P) receptor agonist
that exerts strong anti-inflammatory effects and was approved as the first oral
drug for the treatment of multiple sclerosis by the US Food and Drug
Administration (FDA) in 2010. FTY720 is mainly associated with unique functional
"antagonist" and "agonist" mechanisms. The functional antagonistic mechanism is
mediated by the transient down-regulation and degradation of S1P receptors on
lymphocytes, which prevents lymphocytes from entering the blood stream from the
lymph node. This subsequently results in the development of lymphopenia and
reduces lymphocytic inflammation. Functional agonistic mechanisms are executed
through S1P receptors expressed on the surface of various cells including
neurons, astrocytes, microglia, and blood vessel endothelial cells. These
functions might play important roles in regulating anti-apoptotic systems,
modulating brain immune and phagocytic activities, preserving the
Blood-Brain-Barrier (BBB), and the proliferation of neural precursor cells.
Recently, FTY720 have shown receptor-independent effects, including
intracellular target bindings and epigenetic modulations. Many researchers have
recognized the positive effects of FTY720 and launched basic and clinical
experiments to test the use of this agent against stroke. Although the mechanism
of FTY720 has not been fully elucidated, its efficacy against cerebral stroke is
becoming clear, not only in animal models, but also in ischemic stroke patients
through clinical trials. In this article, we review the data obtained from
laboratory findings and preliminary clinical trials using FTY720 for stroke
treatment. |
Describe SPar-K | SPar-K is a method to search for archetypical chromatin architectures by partitioning a set of genomic regions characterized by chromatin signal profiles around ChIP-seq peaks and other kinds of functional sites. This method efficiently deals with problems of data heterogeneity, limited misalignment of anchor points and unknown orientation of asymmetric patterns. | SUMMARY: We present SPar-K (Signal Partitioning with K-means), a method to
search for archetypical chromatin architectures by partitioning a set of genomic
regions characterized by chromatin signal profiles around ChIP-seq peaks and
other kinds of functional sites. This method efficiently deals with problems of
data heterogeneity, limited misalignment of anchor points and unknown
orientation of asymmetric patterns.
AVAILABILITY AND IMPLEMENTATION: SPar-K is a C++ program available on GitHub
https://github.com/romaingroux/SPar-K and Docker Hub
https://hub.docker.com/r/rgroux/spar-k.
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
What is the mechanism of action of donanemab? | Donanemab is a new monoclonal antibody that uniquely targets Aβ(p3-42), a pyroglutamate form of Amyloid-β (Aβ) exclusively found in plaques. | BACKGROUND: A hallmark of Alzheimer's disease is the accumulation of amyloid-β
(Aβ) peptide. Doemab, an antibody that targets a modified form of deposited
Aβ, is being investigated for the treatment of early Alzheimer's disease.
METHODS: We conducted a phase 2 trial of doemab in patients with early
symptomatic Alzheimer's disease who had tau and amyloid deposition on
positron-emission tomography (PET). Patients were randomly assigned in a 1:1
ratio to receive doemab (700 mg for the first three doses and 1400 mg
thereafter) or placebo intravenously every 4 weeks for up to 72 weeks. The
primary outcome was the change from baseline in the score on the Integrated
Alzheimer's Disease Rating Scale (iADRS; range, 0 to 144, with lower scores
indicating greater cognitive and functional impairment) at 76 weeks. Secondary
outcomes included the change in scores on the Clinical Dementia Rating Scale-Sum
of Boxes (CDR-SB), the 13-item cognitive subscale of the Alzheimer's Disease
Assessment Scale (ADAS-Cog13), the Alzheimer's Disease Cooperative
Study-Instrumental Activities of Daily Living Inventory (ADCS-iADL), and the
Mini-Mental State Examination (MMSE), as well as the change in the amyloid and
tau burden on PET.
RESULTS: A total of 257 patients were enrolled; 131 were assigned to receive
doemab and 126 to receive placebo. The baseline iADRS score was 106 in both
groups. The change from baseline in the iADRS score at 76 weeks was -6.86 with
doemab and -10.06 with placebo (difference, 3.20; 95% confidence interval,
0.12 to 6.27; P = 0.04). The results for most secondary outcomes showed no
substantial difference. At 76 weeks, the reductions in the amyloid plaque level
and the global tau load were 85.06 centiloids and 0.01 greater, respectively,
with doemab than with placebo. Amyloid-related cerebral edema or effusions
(mostly asymptomatic) occurred with doemab.
CONCLUSIONS: In patients with early Alzheimer's disease, doemab resulted in a
better composite score for cognition and for the ability to perform activities
of daily living than placebo at 76 weeks, although results for secondary
outcomes were mixed. Longer and larger trials are necessary to study the
efficacy and safety of doemab in Alzheimer's disease. (Funded by Eli Lilly;
TRAILBLAZER-ALZ ClinicalTrials.gov number, NCT03367403.). INTRODUCTION: Alzheimer's disease is the leading cause of disability and poor
health, takes a huge emotional and ficial burden on family caregivers, and is
costly. Doemab (LY3002813) is a new monoclonal antibody that uniquely targets
Aβ(p3-42), a pyroglutamate form of Amyloid-β (Aβ) exclusively found in plaques.
AREAS COVERED: The phase 2 trial of doemab in participants with early
symptomatic Alzheimer's disease, TRAILBLAZER-ALZ. Doemab reduced cerebral
plaque but not tau load and only marginally improved the primary outcome of
cognition and activities of daily living (p = 0.04) without altering individual
measures of these.
EXPERT OPINION: In TRAILBLAZER-ALZ, anticholinesterase use was given at the
beginning but not the end of the trial, and thus, it is not known whether
changes in this or other medicines were involved in the outcome with doemab.
Tau load (measured with flortuacipir PET) may be a biomarker of cognition but
was not altered by doemab. As there is no clear evidence that removing
cerebral amyloid plaques with Aβ antibodies, such as doemab, improves
cognition and the activities of daily living in Alzheimer's disease, clinical
trials with these agents should be abandoned, and more time and money should
spend on further investigating the underlying cause of Alzheimer's disease. The discussion of whether amyloid plaque Aβ is a valid drug target to fight
Alzheimer's disease (AD) has been a matter of scientific dispute for decades.
This question can only be settled by successful clinical trials and the approval
of disease-modifying drugs. However, many clinical trials with antibodies
against different regions of the amyloid Aβ peptide have been discontinued, as
they did not meet the clinical endpoints required. Recently, passive
immunization of AD patients with Doemab, an antibody directed against the
N-terminus of pyroglutamate Aβ, showed beneficial effects in a phase II trial,
supporting the concept that N-truncated Aβ is a relevant target for AD therapy.
There is long-standing evidence that N-truncated Aβ variants are the main
variants found in amyloid plaques besides full-length Aβ1-42, t, therefore their
role in triggering AD pathology and as targets for drug development are of
interest. While the contribution of pyroglutamate Aβ3-42 to AD pathology has
been well studied in the past, the potential role of Aβ4-42 has been largely
neglected. The present review will therefore focus on Aβ4-42 as a possible drug
target based on human and mouse pathology, in vitro and in vivo toxicity, and
anti-Aβ4-X therapeutic effects in preclinical models. The inhibition of glutaminyl cyclase (QC) may provide a promising strategy for
the treatment of early Alzheimer's disease (AD) by reducing the amount of the
toxic pyroform of β-amyloid (AβΝ3pE) in the brains of AD patients. In this work,
we identified potent QC inhibitors with subomolar IC50 values that were up to
290-fold higher than that of PQ912, which is currently being tested in Phase II
clinical trials. Among the tested compounds, the cyclopentylmethyl derivative
(214) exhibited the most potent in vitro activity (IC50 = 0.1 nM), while
benzimidazole (227) showed the most promising in vivo efficacy, selectivity and
druggable profile. 227 significantly reduced the concentration of pyroform Aβ
and total Aβ in the brain of an AD animal model and improved the alternation
behavior of mice during Y-maze tests. The crystal structure of human QC (hQC) in
complex with 214 indicated tight binding at the active site, supporting that the
specific inhibition of QC results in potent in vitro and in vivo activity.
Considering the recent clinical success of doemab, which targets AβΝ3pE,
small molecule-based QC inhibitors may also provide potential therapeutic
options for early-stage AD treatment. Compelling evidence suggests that pyroglutamate-modified Aβ (pGlu3-Aβ; AβN3pG)
peptides play a pivotal role in the development and progression of Alzheimer's
disease (AD). Approaches targeting pGlu3-Aβ by glutaminyl cyclase (QC)
inhibition (Varoglutamstat) or monoclonal antibodies (Doemab) are currently
in clinical development. Here, we aimed at an assessment of combination therapy
of Varoglutamstat (PQ912) and a pGlu3-Aβ-specific antibody (m6) in transgenic
mice. Whereas the single treatments at subtherapeutic doses show moderate
(16-41%) but statistically insignificant reduction of Aβ42 and pGlu-Aβ42 in mice
brain, the combination of both treatments resulted in significant reductions of
Aβ by 45-65%. Evaluation of these data using the Bliss independence model
revealed a combination index of ≈1, which is indicative for an additive effect
of the compounds. The data are interpreted in terms of different pathways, in
which the two drugs act. While PQ912 prevents the formation of pGlu3-Aβ in
different compartments, the antibody is able to clear existing pGlu3-Aβ
deposits. The results suggest that combination of the small molecule
Varoglutamstat and a pE3Aβ-directed monoclonal antibody may allow a reduction of
the individual compound doses while maintaining the therapeutic effect. One of the central aims in Alzheimer's disease (AD) research is the
identification of clinically relevant drug targets. A plethora of potential
molecular targets work very well in preclinical model systems both in vitro and
in vivo in AD mouse models. However, the lack of translation into clinical
settings in the AD field is a challenging endeavor. Although it is long known
that N-terminally truncated and pyroglutamate-modified Abeta (AβpE3) peptides
are abundantly present in the brain of AD patients, form stable and soluble
low-molecular weight oligomers, and induce neurodegeneration in AD mouse models,
their potential as drug target has not been generally accepted in the past. This
situation has dramatically changed with the report that passive immunization
with doemab, an AβpE3-specific antibody, cleared aymloid plaques and
stabilized cognitive deficits in a group of patients with mild AD in a phase II
trial. This review summarizes the current knowledge on the molecular mechanisms
of generation of AβpE, its biochemical properties, and the intervention points
as a drug target in AD. |
Is cytokeratin a tumor marker? | Yes,
cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) is a tumor marker. | PURPOSE: To explore the concentration of squamous cell carcinoma antigen (SCCA),
cytokeratin fragment antigen 21-1 (CYFRA21-1) in patients with laryngeal
squamous cell carcinoma (LSCC) and its correlation with tumorigenesis and
progression.
METHODS: A total of 78 patients with LSCC admitted to our hospital from February
2010 to January 2016 were enrolled as the research group (RG), and another 41
healthy volunteers from the same period were selected as the control group (CG).
The serum concentrations of SCCA and CYFRA21-1 in patients with LSCC were
detected by ELISA, whose diagnostic value in LSCC were further analyzed by ROC
curve. The prognosis and survival curves of patients with LSCC were observed
according to the median value of serum SCCA and CYFRA21-1 concentrations.
RESULTS: The concentration of CYFRA21-1 and SCCA in the RG was significantly
higher than that in the CG (p < 0.050). The SCCA and CYFRA21-1 identified a
significant difference in smoking, lymphatic metastasis, TNM staging, and
differentiation degree (p < 0.050). The survival rate of the SCCA
low-concentration group was significantly better than that of the
high-concentration group, p < 0.050. The survival rate of the CYFRA21-1
low-concentration group was markedly better than that of the high-concentration
group, p < 0.050.
CONCLUSIONS: SCCA and CYFRA21-1 are highly concentrated in LSCC patients, which
have good diagnostic efficacy for LSCC. In addition, they play some certain role
in the occurrence and development of LSCC, and are expected to be markers for
early diagnosis and prognosis of this disease. PURPOSE: We aimed to develop a novel method for orthotopic colon cancer model,
using tissue adhesive in place of conventional surgical method.
MATERIALS AND METHODS: RFP HCT 116 cell line were used to establish the colon
cancer model. Fresh tumor tissue harvested from a subcutaneous injection was
grafted into twenty nude mice, divided into group A (suture method) and group B
(tissue adhesive method). For the group A, we fixed the tissue on the serosa
layer of proximal colon by 8-0 surgical suture. For the group B, tissue adhesive
(10 μL) was used to fix the tumor. The mortality, tumor implantation success,
tumor metastasis, primary tumor size, and operation time were compared between
the two groups. Dissected tumor tissue was analyzed for the histology and
immunohistochemistry. Also, we performed tumor marker analysis.
RESULTS: We observed 30% increase in graft success and 20% decrease in
mortality, by using tissue adhesive method, respectively. The median colon tumor
size was significantly increased by 4 mm and operation time was shortened by 6.5
minutes. The H&E showed similar tumor structure between the two groups. The
immunohistochemistry staining for cancer antigen 19-9, carcinoembryonic antigen,
cytokeratin 20, and Ki-67 showed comparable intensities in both groups.
Real-time quantitative reverse transcription analysis showed eight out of nine
tumor markers are unchanged in the tissue adhesive group. Western blot indicated
the tissue adhesive group expressed less p-JNK (apototic marker) and more
p-MEK/p-p38 (proliferation marker) levels.
CONCLUSION: We concluded the tissue adhesive method is a quick and safe way to
generate orthotopic, colon cancer model. OBJECTIVE: The main aims of this study were to explore the relationships between
serum tumor markers and connective tissue disease-related interstitial lung
disease (CTD-ILD) and to evaluate the clinical value of tumor markers for
investigating interstitial lung disease (ILD) in patients with connective tissue
disease (CTD).
METHODS: The study included 235 patients with CTD (90 CTD without ILDs, 145
CTD-ILD). Clinical information and the levels of inflammatory and tumor markers,
including carbohydrate antigen (CA) 19-9, CA125, carcinoembryonic antigen (CEA),
CA153, and cytokeratin 19 fragments (CYFRA21-1), were obtained in all the
patients.
RESULTS: A significant difference between CTD with or without ILD and higher
levels of tumor markers was observed in the CTD-ILD group, including CA19-9
(p<0.001), CEA (p<0.001), CA153 (p<0.001), and CYFRA21-1 (p<0.001). There was no
significant difference in serum tumor marker levels in the various types of CTD
(rheumatoid arthritis, systemic lupus erythematosus, Sjogren's syndrome,
inflammatory myositis, systemic sclerosis, and mixed connective tissue disease).
The levels of CA153 [odds ratio (OR)=1.159] and CYFRA21-1 (OR=2.269) were
clearly related to the risk of CTD-ILD. The diagnostic value of CA153 [area
under receiver operating characteristic curve (AUC)=0.736] and CYFRA21-1
(AUC=0.718) was confirmed for ILDs in CTD patients, at cut-off values of 9.45
U/mL and 2.13 ng/mL, respectively.
CONCLUSION: There is a positive correlation between serum tumor marker levels
and CTD-ILD. Higher levels of CA153 and CYFRA21-1 suggest an increased risk of
developing ILD and may therefore be useful as biomarkers for detecting CTD-ILD
in the clinical setting. |
What are TAMs in cancer therapy? | TAMs are Tumor Associated Macrophages and are important in Cancer therapy. | Macrophages are one of the principal host cell populations in solid tumors. They
are capable, due to their plasticity, of acquiring phenotypes that either combat
(M1 type) or promote (M2 type) neoplastic growth. These cells, known as
tumor-associated macrophages (TAMs), play complex but pivotal roles in the
outcome of photodynamic therapy (PDT) of maligt lesions. Among the various
parenchymal and stromal cell populations found in tumors, TAMs have been shown
to have the greatest capacity for the uptake of systemically administered
photosensitizers. Both the tumor-localizing property of photosensitizers and
their tumor-localized fluorescence could be partly attributed to the activity of
TAMs. Since resident TAMs with accumulated high photosensitizer content will
sustain high degrees of PDT damage, this population (predomitly M2 in most
tumors) is selectively destroyed, and during the ensuing inflammatory reaction
is replaced with newly invading macrophages of M1 phenotype. These macrophages
are sentinels responding to DAMP signals from PDT-treated tumor cells and in
turn are mobilized to generate a variety of inflammatory/immune mediators and
opsonins. They have a critical role in contributing to the therapeutic effect of
PDT by mediating disposal of killed cancer cells and by processing/presenting
tumor antigens to T lymphocytes. However, TAMs accumulating in the later
post-PDT phase can acquire the M2 (healing) phenotype, and could have a role in
tumor recurrence by releasing factors that promote angiogenesis and the
survival/proliferation of remaining cancer cells. Various therapeutic strategies
modulating TAM activity in the PDT response have potential for clinical use for
improving PDT-mediated tumor control. Cancer therapy has developed around the concept of killing, or stopping the
growth of, the cancer cells. Molecularly targeted therapy is the modern
expression of this paradigm. Increasingly, however, the realization that the
cancer has co-opted the normal cells of the stroma for its own survival has led
to the concept that the tumor microenvironment (TME) could be targeted for
effective therapy. In this review, we outline the importance of tumor-associated
macrophages (TAM), a major component of the TME, in the response of tumors to
cancer therapy. We discuss the normal role of macrophages in wound healing, the
major phenotypes of TAMs, and their role in blunting the efficacy of cancer
treatment by radiation and anticancer drugs, both by promoting tumor
angiogenesis and by suppressing antitumor immunity. Finally, we review the many
preclinical studies that have shown that the response of tumors to irradiation
and anticancer drugs can be improved, sometimes markedly so, by depleting TAMs
from tumors or by suppressing their polarization from an M1 to an M2 phenotype.
The data clearly support the validity of clinical testing of combining targeting
TAMs with conventional therapy. Clin Cancer Res; 23(13); 3241-50. ©2017 AACR. Eliciting effective antitumor immune responses in patients who fail checkpoint
inhibitor therapy is a critical challenge in cancer immunotherapy, and in such
patients, tumor-associated myeloid cells and macrophages (TAMs) are promising
therapeutic targets. We demonstrate in an autochthonous, poorly immunogenic
mouse model of melanoma that combination therapy with an agonistic anti-CD40 mAb
and CSF-1R inhibitor potently suppressed tumor growth. Microwell assays to
measure multiplex protein secretion by single cells identified that untreated
tumors have distinct TAM subpopulations secreting MMP9 or cosecreting CCL17/22,
characteristic of an M2-like state. Combination therapy reduced the frequency of
these subsets, while simultaneously inducing a separate polyfunctional
inflammatory TAM subset cosecreting TNF-α, IL-6, and IL-12. Tumor suppression by
this combined therapy was partially dependent on T cells, and on TNF-α and
IFN-γ. Together, this study demonstrates the potential for targeting TAMs to
convert a "cold" into an "inflamed" tumor microenvironment capable of eliciting
protective T cell responses. Purpose: Cancer stem-like cells (CSC) contribute to the progression and androgen
deprivation therapy (ADT) resistance of prostate cancer. As CSCs depend on their
specific niche, including tumor-associated macrophages (TAM), elucidating the
network between CSCs and TAMs may help to effectively inhibit the progression
and ADT resistance of prostate cancer.Experimental Design: The underlying
intracellular mechanism that sustains the stem-like characteristics of CSCs in
prostate cancer was assessed via RNA sequencing, co-immunoprecipitation,
chromatin immunoprecipitation, and other assays. A coculture system and cytokine
antibody arrays were used to examine the interaction network between CSCs and
TAMs. In addition, an orthotopic prostate cancer model was established to
evaluate the in vivo effects of the combined targeting of CSCs and their
interaction with TAMs on ADT resistance.Results: Autophagy-related gene 7 (ATG7)
facilitated the transcription of OCT4 via β-catenin, which binds to the OCT4
promoter, promoting CSC characteristics in prostate cancer, including
self-renewal, tumor initiation, and drug resistance. In addition, CSCs remodeled
their specific niche by educating monocytes/macrophages toward TAMs, and the
CSC-educated TAMs reciprocally promoted the stem-like properties of CSCs,
progression and ADT resistance of prostate cancer via IL6/STAT3. Furthermore,
the combined targeting of CSCs and their interaction with TAMs by inhibiting
ATG7/OCT4 and IL6 receptor effectively ameliorated ADT resistance in an
orthotopic prostate cancer model.Conclusions: Targeting CSCs and their niche may
prove to be a more powerful strategy than targeting CSCs alone, providing a
rational approach to ameliorating ADT resistance in prostate cancer. Clin Cancer
Res; 24(18); 4612-26. ©2018 AACR. Tumorigenesis is not only determined by the intrinsic properties of cancer cells
but also by their interactions with components of the tumor microenvironment
(TME). Tumor-associated macrophages (TAMs) are among the most abundant immune
cells in the TME. During initial stages of tumor development, macrophages can
either directly promote antitumor responses by killing tumor cells or indirectly
recruit and activate other immune cells. As genetic changes occur within the
tumor or T helper 2 (TH 2) cells begin to dominate the TME, TAMs begin to
exhibit an immunosuppressive protumor phenotype that promotes tumor progression,
metastasis, and resistance to therapy. Thus, targeting TAMs has emerged as a
strategy for cancer therapy. To date, TAM targeting strategies have focused on
macrophage depletion and inhibition of their recruitment into the TME. However,
these strategies have shown limited therapeutic efficacy, although trials are
still underway with combination therapies. The fact that macrophages have the
potential for antitumor activity has moved the TAM targeting field toward the
development of TAM-reprogramming strategies to support this antitumor immune
response. Here, we discuss the various roles of TAMs in cancer therapy and their
immunosuppressive properties, as well as implications for emerging checkpoint
inhibitor-based immunotherapies. We review state-of-the-art TAM-targeting
strategies, focusing on current ones at the preclinical and clinical trial
stages that aim to reprogram TAMs as an oncological therapy. Tumor-associated macrophages (TAMs) represent the most abundant innate immune
cells in tumors. TAMs, exhibiting anti-inflammatory phenotype, are key players
in cancer progression, metastasis and resistance to therapy. A high TAM
infiltration is generally associated with poor prognosis, but macrophages are
highly plastic cells that can adopt either proinflammatory/antitumor or
anti-inflammatory/protumor features in response to tumor microenvironment
stimuli. In the context of cancer therapy, many anticancer therapeutics, apart
from their direct effect on tumor cells, display different effects on TAM
activation status and density. In this review, we aim to evaluate the indirect
effects of anticancer therapies in the modulation of TAM phenotypes and
pro/antitumor activity. In the last decade, it has been well-established that tumor-infiltrating myeloid
cells fuel not only the process of carcinogenesis through cancer-related
inflammation mechanisms, but also tumor progression, invasion, and metastasis.
In particular, tumor-associated macrophages (TAMs) are the most abundant
leucocyte subset in many cancers and play a major role in the creation of a
protective niche for tumor cells. Their ability to generate an
immune-suppressive environment is crucial to escape the immune system and to
allow the tumor to proliferate and metastasize to distant sites. Conventional
therapies, including chemotherapy and radiotherapy, are often not able to limit
cancer growth due to the presence of pro-tumoral TAMs; these are also
responsible for the failure of novel immunotherapies based on immune-checkpoint
inhibition. Several novel therapeutic strategies have been implemented to
deplete TAMs; however, more recent approaches aim to use TAMs themselves as
weapons to fight cancer. Exploiting their functional plasticity, the
reprogramming of TAMs aims to convert immunosuppressive and pro-tumoral
macrophages into immunostimulatory and anti-tumor cytotoxic effector cells. This
shift eventually leads to the reconstitution of a reactive immune landscape able
to destroy the tumor. In this review, we summarize the current knowledge on
strategies able to reprogram TAMs with single as well as combination therapies. OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is the most lethal maligcy
and lacks effective treatment. We aimed to understand molecular mechanisms of
the intertwined interactions between tumour stromal components in metastasis and
to provide a new paradigm for PDAC therapy.
DESIGN: Two unselected cohorts of 154 and 20 patients with PDAC were subjected
to correlation between interleukin (IL)-33 and CXCL3 levels and survivals.
Unbiased expression profiling, and genetic and pharmacological gain-of-function
and loss-of-function approaches were employed to identify molecular signalling
in tumour-associated macrophages (TAMs) and myofibroblastic cancer-associated
fibroblasts (myoCAFs). The role of the IL-33-ST2-CXCL3-CXCR2 axis in PDAC
metastasis was evaluated in three clinically relevant mouse PDAC models.
RESULTS: IL-33 was specifically elevated in human PDACs and positively
correlated with tumour inflammation in human patients with PDAC. CXCL3 was
highly upregulated in IL-33-stimulated macrophages that were the primary source
of CXCL3. CXCL3 was correlated with poor survival in human patients with PDAC.
Mechanistically, activation of the IL-33-ST2-MYC pathway attributed to high
CXCL3 production. The highest level of CXCL3 was found in PDAC relative to other
cancer types and its receptor CXCR2 was almost exclusively expressed in CAFs.
Activation of CXCR2 by CXCL3 induced a CAF-to-myoCAF transition and α-smooth
muscle actin (α-SMA) was uniquely upregulated by the CXCL3-CXCR2 signalling.
Type III collagen was identified as the CXCL3-CXCR2-targeted adhesive molecule
responsible for myoCAF-driven PDAC metastasis.
CONCLUSIONS: Our work provides novel mechanistic insights into understanding
PDAC metastasis by the TAM-CAF interaction and targeting each of these
signalling components would provide an attractive and new paradigm for treating
pancreatic cancer. Tumor-associated macrophages (TAMs) of M2 phenotype have mediated the
immunosuppression in a tumor microenvironment, facilitating the escape of tumor
cells from immunosurveillance. Reprograming the immunosuppressive M2 TAMs to
immunostimulatory M1 phenotype can activate the antitumor immune responses for
cancer immunotherapy. Herein, hollow iron oxide (Fe3O4) oparticles (NPs) were
employed to reprogram M2 TAMs toward M1 TAMs, aiming to release proinflammatory
cytokines and recruit T cells to kill tumor cells. After loaded with l-arginine
(l-Arg) and sealed with poly(acrylic acid) (PAA), hollow Fe3O4 NPs were
fabricated into LPFe3O4 NPs, which could release l-Arg based on pH-responsive
PAA and produce nitric oxide (NO) with the help of nitric oxide synthase (iNOS)
overexpressed by M1 TAMs, as a result of additional tumor elimination for gas
therapy. In vitro and in vivo studies demonstrate that LPFe3O4 NPs could
effectively reprogram M2 to M1 macrophages, activating T cells, releasing TNF-α,
and producing high levels of NO, leading to synergistic tumor therapy. Endocrine therapy is the standard treatment for estrogen receptor (ER)-positive
breast cancer, but tumors eventually develop resistance. However, endocrine
therapy resistance mechanisms mediated through interactions between breast
cancer cells and tumor-associated macrophages (TAMs) are still unclear. Here, we
characterized sodium/glucose cotransporter 1 (SGLT1) overexpression drives the
highly glycolytic phenotype of tamoxifen-resistant breast cancer cells where
enhanced lactic acid secretion promotes M2-like TAM polarization via the
hypoxia-inducible factor-1α/signal transducer and activator of transcription-3
pathway. In turn, M2-like TAMs activate breast cancer cells through
EGFR/PI3K/Akt signaling, providing feedback to upregulate SGLT1 and promote
tamoxifen resistance and accelerate tumor growth in vitro and in vivo. Higher
expression of SGLT1 and CD163+ TAMs was associated with endocrine-resistant
ER-positive breast cancers. Our study identifies a novel vicious cycle of
metabolic reprogramming, M2-like TAM polarization, and endocrine therapy
resistance, which involves SGLT1, proposing SGLT1 as a therapeutic target to
overcome endocrine therapy resistance in breast cancer. Inflammation is a fundamental physiological response orchestrated by innate
immune cells to restore tissue homeostasis. Specialized pro-resolving mediators
(SPMs) are involved in active resolution of inflammation but when inflammation
is incomplete, chronic inflammation creates a favorable environment that fuels
carcinogenesis and cancer progression. Conventional cancer therapy also
strengthens cancer-related inflammation by inducing massive tumor cell death
that activate surrounding immune-infiltrating cells such as tumor-associated
macrophages (TAMs). Macrophages are key actors of both inflammation and its
active resolution due to their plastic phenotype. In line with this high
plasticity, macrophages can be hijacked by cancer cells to support tumor
progression and immune escape, or therapy resistance. Impaired resolution of
cancer-associated inflammation supported by TAMs may thus reinforces tumor
progression. From this perspective, recent evidence suggests that stimulating
macrophage's pro-resolving functions using SPMs can promote inflammation
resolution in cancer and improve anticancer treatments. Thus, TAMs' re-education
toward an antitumor phenotype by using SPMs opens a new line of attack in cancer
treatment. Here, we review SPMs' anticancer capacities with special attention
regarding their effects on TAMs. We further discuss how this new therapeutic
approach could be envisioned in cancer therapy. Melanoma is one of the most common maligt tumors. The anti-PD-1 antibody is
used for the treatment of metastatic melanoma. Treatment success is only 35-40%
and a range of immune-related adverse reactions can occur. Combination of
anti-PD1 antibody therapy with other oncology therapies has been attempted.
Herein, we assessed whether chlorogenic acid liposomes modified with sialic acid
(CA-SAL) combined with anti-PD1 antibody treatment was efficacious as
immunotherapy for melanoma. CA-SAL liposomes were prepared and characterized. In
a mouse model of B16F10 tumor, mice were treated with an anti-PD1 antibody,
CA-SAL, or combination of CA-SAL + anti-PD1 antibody, and compared with no
treatment controls. The tumor inhibition rate, tumor-associated macrophages
(TAMs) phenotype, T-cell activity, and safety were investigated. We observed a
significant decrease in the proportion of M2-TAMs and CD4+Fop3+ T cells, while
there was a significant increase in the proportion of M1-TAMs and CD8+ T cells,
and in the activity of T cells, and thus in the tumor inhibition rate. No
significant toxicity was observed in major organs. CA-SAL and anti-PD1 Ab
combination therapy presented synergistic anti-tumor activity, which enhanced
the efficacy of the PD-1 checkpoint blocker in a mouse model of melanoma. In
summary, combination immunotherapy of CA-SAL and anti-PD1 Ab has broad prospects
in improving the therapeutic effect of melanoma, and may provide a new strategy
for clinical treatment. |
What is the relationship between RUNX1T1 and FTO? | FTO controls exonic splicing of adipogenic regulatory factor RUNX1T1 by regulating m6A levels around splice sites and thereby modulates differentiation. The effect of FTO on adipogenesis appears to be mediated via enhanced expression of the pro-adipogenic short isoform of RUNX1T1. | The fat mass and obesity-associated (FTO) gene plays a pivotal role in
regulating body weight and fat mass; however, the underlying mechanisms are
poorly understood. Here we show that primary adipocytes and mouse embryonic
fibroblasts (MEFs) derived from FTO overexpression (FTO-4) mice exhibit
increased potential for adipogenic differentiation, while MEFs derived from FTO
knockout (FTO-KO) mice show reduced adipogenesis. As predicted from these
findings, fat pads from FTO-4 mice fed a high-fat diet show more numerous
adipocytes. FTO influences adipogenesis by regulating events early in
adipogenesis, during the process of mitotic clonal expansion. The effect of FTO
on adipogenesis appears to be mediated via enhanced expression of the
pro-adipogenic short isoform of RUNX1T1, which enhanced adipocyte proliferation,
and is increased in FTO-4 MEFs and reduced in FTO-KO MEFs. Our findings provide
novel mechanistic insight into how upregulation of FTO leads to obesity. |
Which java utility has been developed for class hidden markov models? | JUCHMME is an open-source software package designed to fit arbitrary custom Hidden Markov Models (HMMs) with a discrete alphabet of symbols, and is used for biological sequence analysis and class hidden markov models in Java EE 8 and Java EE 9. | SUMMARY: JUCHMME is an open-source software package designed to fit arbitrary
custom Hidden Markov Models (HMMs) with a discrete alphabet of symbols. We
incorporate a large collection of standard algorithms for HMMs as well as a
number of extensions and evaluate the software on various biological problems.
Importantly, the JUCHMME toolkit includes several additional features that allow
for easy building and evaluation of custom HMMs, which could be a useful
resource for the research community.
AVAILABILITY AND IMPLEMENTATION: http://www.compgen.org/tools/juchmme,
https://github.com/pbagos/juchmme.
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
What is the mechanism of action of Etesevimab? | Etesevimab is a neutralizing antibody indicated for treatment of coronavirus disease 2019 (COVID-19) in patients with early mild or moderate disease. | Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread
rapidly worldwide. This study is the first to report the tolerability, safety,
pharmacokinetics (PK), and immunogenicity of a recombit human anti-SARS-CoV-2
monoclonal antibody, etesevimab (CB6, JS016, LY3832479, or LY-CoV016), in
healthy adults. This paper describes a randomized, double-blind,
placebo-controlled, phase 1 study. A total of 40 participants were enrolled to
receive a single intravenous dose of either etesevimab or placebo in one of four
sequential ascending intravenous dose cohorts. All 40 participants completed the
study. Seventeen (42.5%) participants experienced 22 treatment emergent adverse
events (TEAEs) that were drug-related, and the rates of these TEAEs among
different dose cohorts were numerically comparable. No difference was observed
between the combined etesevimab group and the placebo group. The exposure after
etesevimab infusion increased in an approximately proportional manner as the
dose increased from 2.5 to 50 mg/kg. The elimination half-life (t1/2) value did
not differ among different dose cohorts and was estimated to be around 4 weeks.
Etesevimab was well tolerated after administration of a single dose at a range
of 2.5 mg/kg to 50 mg/kg in healthy Chinese adults. The PK profiles of
etesevimab in healthy volunteers showed typical monoclonal antibody distribution
and elimination characteristics. (This study has been registered at
ClinicalTrials.gov under identifier NCT04441918.). Infection by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)
causes COVID-19 disease. Therapeutic antibodies are being developed that
interact with the viral spike proteins to limit viral infection of epithelium.
We have applied a method to dramatically improve the performance of
anti-SARS-CoV-2 antibodies by enhancing avidity through multimerization using
simple engineering to yield tetrameric antibodies. We have re-engineered six
anti-SARS-CoV-2 antibodies using the human p53 tetramerization domain, including
three clinical trials antibodies casirivimab, imdevimab and etesevimab. The
method yields tetrameric antibodies, termed quads, that retain efficient binding
to the SARS-CoV-2 spike protein, show up to two orders of magnitude enhancement
in neutralization of pseudovirus infection and retain potent interaction with
virus variant of concern spike proteins. The tetramerization method is simple,
general and its application is a powerful methodological development for
SARS-CoV-2 antibodies that are currently in pre-clinical and clinical
investigation. The severity of coronavirus disease 2019 (COVID-19) ranges from mild to death,
with high morbidity and mortality rates reported amongst a vulnerable subset of
patients termed high risk. While vaccines remain the primary option for COVID-19
prevention, neutralizing monoclonal antibodies (mAbs), such as bamlanivimab and
etesevimab, have been shown to benefit certain subpopulations after exposure to
severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Unlike
vaccine-derived immunity that develops over time, administration of neutralizing
mAbs is an immediate and passive immunotherapy, with the potential to reduce
disease progression, emergency room visits, hospitalizations, and death.
Bamlanivimab alone and together with etesevimab hold emergency use
authorizations in several countries globally, with countries increasingly
transitioning to the use of bamlanivimab and etesevimab together and other
authorized mAbs on the basis of their evolving variant landscape, regulatory
authorizations, and access to drugs. The current guidelines for the
administration of bamlanivimab alone or together with etesevimab are informed by
an iterative process of testing and development. Herein the rationale for these
guidelines is provided by sharing the learnings that have been gathered
throughout the development process of these mAbs. In addition, this review
addresses the most common clinical questions received from health care
professionals (HCPs) and patients regarding indicated population, dose, use with
other medications and vaccines, duration of protection, and variants in clinical
practice. As prevalence of SARS-CoV-2 variants can differ by country and state,
prescribing HCPs should consider the prevalence of bamlanivimab and etesevimab
resistant variants in their area, where data are available, regarding potential
efficacy impact when considering treatment options.Trial Registration:
ClinicalTrials.gov identifier: NCT04427501; NCT04411628; NCT04497987;
NCT04634409. Patients with the monogenic immune dysregulatory syndrome autoimmune
polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), which is caused by
loss-of-function mutations in the autoimmune regulator (AIRE) gene, uniformly
carry neutralizing autoantibodies directed against type-I interferons (IFNs) and
many develop autoimmune pneumonitis, both of which place them at high risk for
life-threatening COVID-19 pneumonia. Bamlanivimab and etesevimab are monoclonal
antibodies (mAbs) that target the SARS-CoV-2 spike protein and block entry of
SARS-CoV-2 in host cells. The use of bamlanivimab and etesevimab early during
infection was associated with reduced COVID-19-associated hospitalization and
death in patients at high risk for progressing to severe disease, which led the
US Food and Drug Administration to issue an emergency use authorization for
their administration in non-hypoxemic, non-hospitalized high-risk patients.
However, the safety and efficacy of these mAbs has not been evaluated in APECED
patients. We enrolled two siblings with APECED on an IRB-approved protocol
(NCT01386437) and admitted them prophylactically at the NIH Clinical Center for
evaluation of mild-to-moderate COVID-19. We assessed the safety and clinical
effects of early treatment with bamlanivimab and etesevimab. The administration
of bamlanivimab and etesevimab was well tolerated and was associated with
amelioration of COVID-19 symptoms and prevention of invasive ventilatory
support, admission to the intensive care, and death in both patients without
affecting the production of antibodies to the nucleocapsid protein of
SARS-CoV-2. If given early in the course of COVID-19 infection, bamlanivimab and
etesevimab may be beneficial in APECED and other high-risk patients with
neutralizing autoantibodies directed against type-I IFNs. This review takes into consideration the principal vaccines developed against
the SARS-CoV-2 in this unprecedented period of Covid-19 pandemic. We evaluated
the mechanism of action of each vaccine as well as the efficacy, the safety and
the storage temperature. In addition, the problem of the dose units, the
vaccinal strategy, the activity of alternative compounds such as the monoclonal
antibodies and especially the issue of the virus variants were also described in
detail. Four vaccines are currently used in Italy: Pfizer-BioNTech mRNA BNT162b2
(Comirnaty) (USA), Moderna mRNA 1273 (USA), Astra-Zeneca ChAdOx1-S (recombit)
viral vector adenovirus belonging to Oxford (UK) and Pomezia (Italy), Janssen
(two recombit viral vector adenoviruses) belonging to Johnson & Johnson
(USA). The efficacy of Pfizer and Moderna for preventing disease or severe
disease results 95-87.5% and 94.5-100%, respectively. The efficacy of
Astra-Zeneca and Janssen is about 70% and 65%, respectively; in the case of
Janssen, it depends on the geographical area ranging from 72% to 57%. The
problem of the administrated doses (one dose, two doses from the same vaccine or
from different vaccines, half dose) is also discussed. The vaccination strategy
based on the age group remains the simplest, most transparent and fair
criterion. This strategy is also based on accelerating the administration of the
vaccines, so that as many subjects as possible can be vaccinated quickly for
achieving the "herd immunity". The monoclonal antibodies appeared to be a valid
solution for the treatment of Covid-19 disease. Two antibodies (bamlanivimab and
etesevimab) have just been approved by the FDA. They could also be used for the
infection by virus variants which represent a big problem due to their higher
transmissibility and virulence and to their lower response to the vaccines. Bamlanivimab and etesevimab are neutralizing antibodies indicated for treatment
of coronavirus disease 2019 (COVID-19) in patients with early mild or moderate
disease. We present the use of pharmacokinetic/pharmacodynamic (PK/PD) modeling
that characterizes the timecourse of viral load obtained from 2,970 patients
from 2 phase II clinical trials. The model was used for identification of
optimal doses that would result in at least 90% of patients achieving serum drug
concentrations that result in 90% of maximum drug effect (IC90) for at least
28 days. The serum IC90 (95% confidence interval) was estimated to be 4.2
(3.2-4.3) µg/mL for bamlanivimab and 12.6 (9.7-12.8) µg/mL for etesevimab.
Observed clinical trial data confirmed PK and PK/PD model predictions that doses
of 700 mg bamlanivimab and 1,400 mg etesevimab would result in maximum reduction
in viral load, with no additional effect seen at higher doses. No dose
adjustment is recommended as age, sex, race, baseline viral load, and hepatic
impairment did not have a significant impact on the PK of the antibodies.
Earlier drug administration resulted in greater reductions in viral load,
demonstrating the importance of receiving treatment as soon as possible.
Relative to placebo, typical reduction in viral load over a 7-day period was
estimated to be 80 or 93% (drug administered 4 days or 1 day after the onset of
symptoms, respectively), P < 0.0001. PK/PD modeling and simulation was pivotal
throughout the drug development and emergency use authorization process. OBJECTIVES: To evaluate the impact of neutralizing monoclonal antibody (mAb)
treatment and to determine whether the selective pressure of mAbs could
facilitate the proliferation of severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2) variants with spike protein mutations that might attenuate mAb
effectiveness.
PATIENTS AND METHODS: We evaluated the impact of mAbs on the nasopharyngeal (NP)
viral load and virus quasispecies of mAb-treated patients using single-molecule
real-time sequencing. The mAbs used were: Bamlanivimab alone (four patients),
Bamlanivimab/Etesevimab (23 patients) and Casirivimab/Imdevimab (five patients).
RESULTS: The NP SARS-CoV-2 viral load of mAb-treated patients decreased from 8.2
log10 copies/mL before administration to 4.3 log10 copies/mL 7 days after
administration. Five immunocompromised patients given Bamlanivimab/Etesevimab
were found to have mAb activity-reducing spike mutations. Two patients harboured
SARS-CoV-2 variants with a Q493R spike mutation 7 days after administration, as
did a third patient 14 days after administration. The fourth patient harboured a
variant with a Q493K spike mutation 7 days post-treatment, and the fifth patient
had a variant with a E484K spike mutation on day 21. The emergence of the spike
mutation was accompanied by stabilization or rebound of the NP viral load in
three of five patients.
CONCLUSION: Two-mAb therapy can drive the selection of resistant SARS-CoV-2
variants in immunocompromised patients. Patients given mAbs should be closely
monitored and measures to limit virus spread should be reinforced. INTRODUCTION: Treatments for subjects with Covid-19 are required. One approach
is neutralizing monoclonal antibodies. Bamlanivimab and etesevimab are
monoclonal antibodies to SARS-CoV-2.
AREAS COVERED: This evaluation is of the phase 3 BLAZE-1 clinical trial, which
was of bamlanivimab plus etesevimab in adult ambulatory participants with a risk
factor for, and mild to moderate, Covid-19 illness. The primary outcome was
Covid 19 related hospitalization of ≥ 24 hours or death from any cause by day
29, and this occurred in 2.1% subjects in the bamlanivimab/etesevimab group,
compared to 7.0% in the placebo group.
EXPERT OPINION: In the pandemic, the attempts by the FDA to shorten approval
processes for medicines and by journals to make information available in a
timely manner are admirable. However, these shortened processes made negotiating
the details of BLAZE-1 and producing accurate and critical appraisals difficult.
It seems to me that if there are any benefits of bamlanivimab alone in Covid-19,
they are not clear-cut. Bamlanivimab has limited effects against the beta and
gamma variants and is not effective against the delta variant. Thus, the
benefits of bamlanivimab/etesevimab in the phase 3 of the BLAZE-1 may be solely
due to etesevimab, and this needs to be tested. |
List known pseudokinases. | TRIB1
TRIB2
TRIB3
MLKL
ULK4
HER3
CASK | ABTL0812 is a first-in-class small molecule with anti-cancer activity, which is
currently in clinical evaluation in a phase 2 trial in patients with advanced
endometrial and squamous non-small cell lung carcinoma (NCT03366480).
Previously, we showed that ABTL0812 induces TRIB3 pseudokinase expression,
resulting in the inhibition of the AKT-MTORC1 axis and
macroautophagy/autophagy-mediated cancer cell death. However, the precise
molecular determits involved in the cytotoxic autophagy caused by ABTL0812
remained unclear. Using a wide range of biochemical and lipidomic analyses, we
demonstrated that ABTL0812 increases cellular long-chain dihydroceramides by
impairing DEGS1 (delta 4-desaturase, sphingolipid 1) activity, which resulted in
sustained ER stress and activated unfolded protein response (UPR) via
ATF4-DDIT3-TRIB3 that ultimately promotes cytotoxic autophagy in cancer cells.
Accordingly, pharmacological manipulation to increase cellular dihydroceramides
or incubation with exogenous dihydroceramides resulted in ER stress, UPR and
autophagy-mediated cancer cell death. Importantly, we have optimized a method to
quantify mRNAs in blood samples from patients enrolled in the ongoing clinical
trial, who showed significant increased DDIT3 and TRIB3 mRNAs. This is the first
time that UPR markers are reported to change in human blood in response to any
drug treatment, supporting their use as pharmacodynamic biomarkers for compounds
that activate ER stress in humans. Finally, we found that MTORC1 inhibition and
dihydroceramide accumulation synergized to induce autophagy and cytotoxicity,
phenocopying the effect of ABTL0812. Given the fact that ABTL0812 is under
clinical development, our findings support the hypothesis that manipulation of
dihydroceramide levels might represents a new therapeutic strategy to target
cancer.Abbreviations: 4-PBA: 4-phenylbutyrate; AKT: AKT serine/threonine kinase;
ATG: autophagy related; ATF4: activating transcription factor 4; Cer: ceramide;
DDIT3: DNA damage inducible transcript 3; DEGS1: delta 4-desaturase,
sphingolipid 1; dhCer: dihydroceramide; EIF2A: eukaryotic translation initiation
factor 2 alpha; EIF2AK3: eukaryotic translation initiation factor 2 alpha kinase
3; ER: endoplasmic reticulum; HSPA5: heat shock protein family A (Hsp70) member
5; MAP1LC3B: microtubule associated protein 1 light chain 3 beta; MEF: mouse
embryonic fibroblast; MTORC1: mechanistic target of rapamycin kinase complex 1;
NSCLC: non-small cell lung cancer; THC: Δ9-tetrahydrocannabinol; TRIB3: tribbles
pseudokinase 3; XBP1: X-box binding protein 1; UPR: unfolded protein response. Despite advancements in management of acute myocardial infarction, this disease
remains one of the leading causes of death. Timely reestablishment of epicardial
coronary blood flow is the cornerstone of therapy; however, substantial amount
of damage can occur as a consequence of cardiac ischaemia/reperfusion (I/R)
injury. It has been previously proposed that the pathway leading to major cell
death, apoptosis, is responsible for cardiac I/R injury. Nevertheless, there is
compelling evidence to suggest that necroptosis, a programmed necrosis,
contributes remarkably to both myocardial injury and microcirculatory
dysfunction following cardiac I/R injury. Receptor-interacting protein kinase 1
(RIPK1), RIPK3, and mixed-lineage kinase domain-like pseudokinase (MLKL) are
shown as the major mediators of necroptosis. In addition to the traditional
perception that RIPK1/RIPK3/MLKL-dependent plasma membrane rupture is
fundamental to this process, several RIPK3-related pathways such as endoplasmic
reticulum stress and mitochondrial fragmentation have also been implicated in
cardiac I/R injury. In this review, reports from both in vitro and in vivo
studies regarding the roles of necroptosis and RIPK3-regulated necrosis in
cardiac I/R injury have been collectively summarized and discussed. Furthermore,
reports on potential interventions targeting these processes to attenuate
cardiac I/R insults to the heart have been presented in this review. Future
investigations adding to the knowledge obtained from these previous studies are
needed in the pursuit of discovering the most effective pharmacological agent to
improve cardiac I/R outcomes. Hypereosinophilia (HE) has been defined as persistent eosinophilia >1.5 × 109/L;
it is broadly divided into primary HE (clonal or neoplastic; HEN),
secondary/reactive HE (HER), or HE of undetermined significance (HEUS) when no
cause is identified. The use of myeloid next-generation sequencing (NGS) panels
has led to the detection of several mutations in patients previously diagnosed
with HEUS, reassigning some patients to the category of HEN, specifically the
World Health Organization category of chronic eosinophilic leukemia, not
otherwise specified (CEL, NOS). Here, we describe a novel somatic JAK1
pseudokinase domain mutation (R629_S632delinsSA) in a patient with HE that had
initially been characterized as a variant of uncertain significance. We
performed functional studies that demonstrated that this mutation results in
growth factor independence of Ba/F3 cells in vitro and activation of the
JAK-STAT pathway. These effects were abrogated by the JAK1/JAK2 inhibitor
ruxolitinib. R629_S632delinsSA is the first known somatic mutation in JAK1
linked to a clonal eosinophilic neoplasm, and highlights the importance of the
JAK-STAT pathway in eosinophil survival. BACKGROUND: Protein kinases are among the largest druggable family of signaling
proteins, involved in various human diseases, including cancers and
neurodegenerative disorders. Despite their clinical relevance, nearly 30% of the
545 human protein kinases remain highly understudied. Comparative genomics is a
powerful approach for predicting and investigating the functions of understudied
kinases. However, an incomplete knowledge of kinase orthologs across fully
sequenced kinomes severely limits the application of comparative genomics
approaches for illuminating understudied kinases. Here, we introduce KinOrtho, a
query- and graph-based orthology inference method that combines full-length and
domain-based approaches to map one-to-one kinase orthologs across 17 thousand
species.
RESULTS: Using multiple metrics, we show that KinOrtho performed better than
existing methods in identifying kinase orthologs across evolutionarily divergent
species and eliminated potential false positives by flagging sequences without a
proper kinase domain for further evaluation. We demonstrate the advantage of
using domain-based approaches for identifying domain fusion events, highlighting
a case between an understudied serine/threonine kinase TAOK1 and a metabolic
kinase PIK3C2A with high co-expression in human cells. We also identify
evolutionary fission events involving the understudied OBSCN kinase domains,
further highlighting the value of domain-based orthology inference approaches.
Using KinOrtho-defined orthologs, Gene Ontology annotations, and machine
learning, we propose putative biological functions of several understudied
kinases, including the role of TP53RK in cell cycle checkpoint(s), the
involvement of TSSK3 and TSSK6 in acrosomal vesicle localization, and potential
functions for the ULK4 pseudokinase in neuronal development.
CONCLUSIONS: In sum, KinOrtho presents a novel query-based tool to identify
one-to-one orthologous relationships across thousands of proteomes that can be
applied to any protein family of interest. We exploit KinOrtho here to identify
kinase orthologs and show that its well-curated kinome ortholog set can serve as
a valuable resource for illuminating understudied kinases, and the KinOrtho
framework can be extended to any protein-family of interest. CASK (Ca2+/calmodulin-dependent Ser/Thr kinase) is a member of the MAGUK
(membrane-associated guanylate kinase) family that functions as neurexin kinases
with roles implicated in neuronal synapses and trafficking. The lack of a
canonical DFG motif, which is altered to GFG in CASK, led to the classification
as a pseudokinase. However, functional studies revealed that CASK can still
phosphorylate substrates in the absence of divalent metals. CASK dysfunction has
been linked to many diseases, including colorectal cancer, Parkinson's disease,
and X-linked mental retardation, suggesting CASK as a potential drug target.
Here, we exploited structure-based design for the development of highly potent
and selective CASK inhibitors based on 2,4-diaminopyrimidine-5-carboxamides
targeting an unusual pocket created by the GFG motif. The presented inhibitor
design offers a more general strategy for the development of pseudokinase
ligands that harbor unusual sequence motifs. It also provides a first chemical
probe for studying the biological roles of CASK. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) are the
standard-of-care treatment for EGFR-mutant non-small cell lung cancers (NSCLC).
However, most patients develop acquired drug resistance to EGFR TKIs. HER3 is a
unique pseudokinase member of the ERBB family that functions by dimerizing with
other ERBB family members (EGFR and HER2) and is frequently overexpressed in
EGFR-mutant NSCLC. Although EGFR TKI resistance mechanisms do not lead to
alterations in HER3, we hypothesized that targeting HER3 might improve efficacy
of EGFR TKI. HER3-DXd is an antibody-drug conjugate (ADC) comprised of
HER3-targeting antibody linked to a topoisomerase I inhibitor currently in
clinical development. In this study, we evaluated the efficacy of HER3-DXd
across a series of EGFR inhibitor-resistant, patient-derived xenografts and
observed it to be broadly effective in HER3-expressing cancers. We further
developed a preclinical strategy to enhance the efficacy of HER3-DXd through
osimertinib pretreatment, which increased membrane expression of HER3 and led to
enhanced internalization and efficacy of HER3-DXd. The combination of
osimertinib and HER3-DXd may be an effective treatment approach and should be
evaluated in future clinical trials in EGFR-mutant NSCLC patients. SIGNIFICANCE:
EGFR inhibition leads to increased HER3 membrane expression and promotes
HER3-DXd ADC internalization and efficacy, supporting the clinical development
of the EGFR inhibitor/HER3-DXd combination in EGFR-mutant lung cancer.See
related commentary by Lim et al., p. 18. |
Where is the body would the Peyer's patches be found | Peyer's patches (PPs) play a major role in intestinal mucosal immunity and are located in the gut. | In the rabbit intestine Peyer's patches can easily be distinguished. They are
found in the jejunum and ileum, but not in the duodenum. The highest number
observed is seven. In most animals the first, i.e. proximally situated patch has
a rather well-defined place in the beginning of the jejunum; similarly, the
last, i.e. distally situated one mostly has its place in the end of the ileum.
The demarcation of the three classical sections of the small intestine is
discussed from a comparative viewpoint with special criticism as to what is
called ileum in man. Unlike the Peyer's patches of rats and mice, which are considered to be
secondary lymphoid organs, the ileal Peyer's patch of sheep is thought to be
responsible for the primary generation of B cells, like the bursa of Fabricius
of birds. The ileal Peyer's patch of sheep shows prenatal maturation,
antigen-independent lymphopoiesis, a rate of lymphocyte production larger than
that of the thymus, and involution at a young age. Follicles contain few T cells
and have an IgM+, relatively immature B lymphocyte population, as judged by
B-cell differentiation markers. The follicle-associated epithelium of the ileal
Peyer's patch is of a special type that sheds carbonic anhydrase-rich,
50-ometer membrane-bounded particles (carbonic anhydrase-reactive particles;
CAP) into the intercellular spaces. The CAP filter into the follicle centre and
are taken up by lymphocytes. They represent the epithelial (bursa-like) element
in an otherwise mesenchymal stroma of reticular cells embedding the follicle
lymphocytes. Transepithelial transport of macromolecules, with the formation of
multivesicular body-like cytoplasmic vacuoles, appears to be the basis for CAP
formation. The jejunal Peyer's patches are devoid of CAP, persist in the adult
animal, contain M cells with clusters of B cells in the follicle-associated
epithelium, and have many CD4+ lymphocytes in the follicles and in the
interfollicular areas. Aggregates of lymphoid follicles in the large intestine
resemble the jejunal Peyer's patches with respect to their lymphocyte population
and the ileal Peyer's patch with respect to their follicle-associated
epithelium. During the course of their recirculation through the body, blood-borne
lymphocytes specifically adhere to high endothelial venules (HEV) within
secondary lymphoid organs such as peripheral lymph nodes (PN) and gut-associated
Peyer's patches (PP). This adherence event, which initiates the extravasation of
the lymphocyte, is highly specific in terms of the class of lymphocyte and the
anatomic location of the HEV. We review evidence that the lymphocyte adhesive
molecule ('homing receptor') involved in attachment to PN HEV is a
carbohydrate-binding receptor (lectin-like) with specificity for
mannose-6-phosphate (M6P)-like ligands. We describe the use of a novel
cytochemical probe for the detection and characterization of cell surface
carbohydrate-binding receptors. Using a M6P-based probe, we show that the
carbohydrate-binding receptor on lymphocytes is closely-related or identical to
the MEL-14 antigen, a putative homing receptor identified by a monoclonal
antibody. Evidence is presented that the lymphocyte attachment sites on both PN
and PP HEV are inactivated by mild periodate oxidation and hence are probably
carbohydrate in nature. Yet, the sites are biochemically distinguishable in that
one class (PN) requires sialidase-sensitive structures whereas the other (PP)
does not. We raise the possibility that diversity in the carbohydrate-based
recognition determits on HEV may underlie the adhesive specificities in this
system. The distribution and number of Peyer's patches (5) in two species of marsupial
mice, Antechinus swainsonii and Antechinus stuartii was found to be the same
even though the length of the intestine in the latter species was half that of
the former. Both species lack a caecum and appendix. The position of the Peyer's
patches is unusual in that the first three Peyer's patches are on the right side
of the small intestine whereas the penultimate and ultimate Peyer's patches are
large, contain many lymphoid follicles and are in an anti-mesenteric position in
the small intestine and sometimes in the large intestine (ultimate Peyer's
patch). The number of Peyer's patches in eutherian mice of similar size, and
intestinal length is greater (13) although the number of Peyer's patch lymphoid
follicles per centimeter intestine is less (1.8) than in A. swainsonii (4) and
A. stuartii (4.4). Marsupial mice have most of their lymphoid follicles confined
to a few large Peyer's patches, whereas eutherian mice have fewer lymphoid
follicles per unit intestinal length, more Peyer's patches (with fewer lymphoid
follicles) evenly distributed along the intestine and more single lymphoid
follicles interspersed between them. Adaptive immune protection of mucous membranes is provided mainly by secretory
IgA (SIgA) antibodies. This first-line defence is accomplished through an
ingenious cooperation between the mucosal B-cell system and the epithelial
glycoprotein called secretory component (SC). This is quantitatively the most
important receptor of the immune system because it is responsible for external
transport of locally produced polymeric IgA (pIgA), which is the major humoral
mediator substance of the whole immune system. Transmembrane SC belongs to the
Ig supergene family and functions as a general pIg receptor, also translocating
pentameric IgM externally to form secretory IgM. The B-cells responsible for
local pIg production are initially stimulated in lymphoepithelial structures,
particularly the Peyer's patches in the distal small intestine, from which they
migrate as memory cells to exocrine tissues all over the body. Mucous membranes
are thus furnished with secretory antibodies in an integrated way, ensuring a
variety of specificities at every secretory site. There is currently great
interest in exploiting this integrated or "common' mucosal immune system for
oral vaccination against pathogenic infectious agents and also to induce
therapeutic peripheral tolerance to ameliorate T-cell-mediated autoimmune
diseases. Much remains to be learnt about antigen uptake and processing
necessary to elicit stimulatory or suppressive mucosal immune responses, and how
normal homeostasis is maintained in the intestinal mucosa. Considerable
information has accumulated about various types of immune deviation that may
lead to local or extraintestinal hypersensitivity reactions against luminal
antigen, but the crucial mechanisms remain obscure. BACKGROUND AND AIMS: Peyer's patches play a major role in intestinal immunity,
are portals of entry for significant pathogens, and may be important in Crohn's
disease. Whereas their microscopic anatomy and immune function are well
described, surprisingly little is known of their macroscopic anatomy and
distribution. Our aim was to assess their number, area, and distribution in the
normal distal ileum, with particular reference to patient age.
METHODS: Distal ilea (200 cm) obtained at autopsy from 55 adults without
intestinal disease were opened along the mesenteric border, fixed in acetic
acid, and transilluminated. Peyer's patches were counted, and the length,
breadth, and distance from the ileocecal valve were recorded.
RESULTS: Patches were most numerous in the terminal 10-15 cm where they formed a
lymphoid ring. More proximal patches were oval, antimesenteric, and irregularly
spaced. By area, 46% of patch tissue occurred in the terminal 25 cm. The mean
number of patches ranged from 29.4 +/- 5.4 in the youngest group studied, to
19.0 +/- 3.0 in the oldest. Total patch area was greatest in the group aged
21-30 (47.4 +/- 1.0 cm2).
CONCLUSION: Peyer's patches are concentrated in the distal 25 cm of ileum but
extend proximally for 200 cm. The variation in their size, shape, and
distribution in different individuals is greater than often appreciated and may
influence the presentation of diseases centered on these structures. In small rumits, the development of B cells differs from that in mice or in
man. The anti-body repertoire is expanded in the Peyer's patches of the terminal
ileum where each B-cell follicle is found by a few cells. To investigate the
amount of founder clones in bovine ileal follicles, we have used sex mismatched
cattle twins. These animals are chimeric due to placental anastomoses.
Y-chromosome targeted in situ hybridization was used to trace donor-derived
cells of the male genotype in a female recipient (called a freemartin). A strong
clustering of lymphoid cells originating from either twin was seen in the ileal
Peyer's patches (IPPs). Furthermore, the follicles displayed a low amount of
immunoglobulin heavy chain gene configurations in comparison with the splenic or
jejunal follicles. These findings strongly suggest that as in sheep, the B-cell
follicles in cattle IPPs develop oligoclonally. Pro-inflammatory mediators hold important functions in human body in response to
infection, trauma and vascular disease. However, their action is down regulated
by the release of anti-inflammatory cytokines, thus restoring a balance which
reflects the immune status of a given individual. Recent studies have stressed
out the importance of circulating levels of cytokines for forensic purposes even
if there is a lack of studies regarding the role of post-mortem
mucosa-associated lymphoid tissue. In this respect, Peyer's patches (PP),
represent one of the most important immunological site of the body and the major
component of the gut -associated lymphoid tissue. The aim of this study was to
evaluate post-mortem PP immune response in 40 serial autopsy cases of people who
died from natural and traumatic death. The study examined spontaneous release of
the following cytokines by fresh isolated PP cells: interleukin (IL)-12, tumor
necrosis factor (TNF)-alpha, IL-10, IL-6, IL-1 beta, and IL-8. Results will show
that higher levels of TNF-alpha, IL-6, IL-1 beta, and IL-8 are statistically
correlated with the traumatic death group. From a forensic point of view these
data demonstrate that fundamental lymphoid organs, such as PP, may have a
potential in diagnosing the cause of death. Peyer's patch have been extensively studied as a major inductive site for
mucosal immunity within the small intestine. The intestinal mucosa contains
numerous dendritic cells, which induce either protective immunity to infectious
agents or tolerance to innocuous antigens, including food and commensal
bacteria. Although during the past few years, several subsets of human mucosal
dendritic cells have been described, a precise characterization of the different
mouse mucosal dendritic cells subpopulations remains to be achieved with regard
to their phenotype and localization in Peyer's patch. In this report, we have
investigated by immunofluorescence on cryosection and by flow cytometry, the
phenotype and the localization of dendritic cells into Peyer's patch of C57Bl/6
mouse intestine using dendritic cells markers. Positive and double staining for
CD11c and BDCA-2, pDC/IPC, DC-LAMP, DC-SIGN, TLR8 and Langerin have been
observed revealing new mouse intestinal DC subsets. This study provides new
insight in the understanding of mucosal immune responses induced by natural
processes as infections but also new perspectives for the evaluation of oral
vaccines. Toll-like receptors (TLRs) are key molecular sensors used by the mammalian
innate immune system to detect microorganisms. Although TLR functions in colonic
immune homeostasis and tolerance to commensal bacteria have been intensively
researched, the precise roles of different TLRs in response to pathogen
infection in the gut remain elusive. Peyer patches are the major entrance of
Salmonella infection and antigen transportation in intestine. Here, we report
that, in contrast to TLR5 as a "carrier of Salmonella," TLR11 works as a
"blocker of Salmonella" to prevent highly invasive Salmonella from penetrating
into the murine Peyer patches and spreading systemically. TLR11 plays an
important role in mediating TNF-α induction and systemic inflammation in
response to Salmonella infection. Remarkably, in mice lacking TLR11, apparent
hemorrhages at Peyer patches are induced by highly invasive Salmonella, a
phenotype resembling human Salmonella infection. Therefore, our results indicate
a potentially important role for TLR11 in preventing murine intestinal infection
and modulating antigen transportation in the gut and imply an important role for
various TLRs in cooperation with tight control of pathogens penetrating into
Peyer patches. The TLR11 knock-out mouse can serve as a good animal model to
study Salmonella infection. BACKGROUND: Oral immunization has numerous advantages over parenteral
administrations. In addition to ease administration, more effective pathogen
elimination on the mucosa before spreading into the blood circulation,
constitutes the main benefit. This is particularly true for pathogens that enter
the body through the oral route. On the other hand, it is the most challenging
administration route for peptides, proteins and recombit antigens due to
gastrointestinal (GI) tract, numerous barriers including the harsh environment
and the inherent weak immunogenicity. In addition to the adjuvant properties,
polymeric particles arise as the most promising strategy to overcome poor
antigen bioavailability/ stability upon oral administration. The Peyer's patches
have been considered an important structure of the gut associate lymphoid tissue
(GALT) for the initiation of the immune response towards particulate oral
antigens.
OBJECTIVE: The transport mechanism of both, o and microparticles across
intestinal mucosa, particularly throughout Peyer's patches, is discussed in this
review.
CONCLUSION: We provide a short and concise update (last decade) focused on the
importance of particle physicochemical properties, M-cell ligands and
size-dependent transport and intracellular fate concerning Peyer's patches
targeted oral vaccination. In mammals, macrophages (MF) are present in virtually all tissues where they
serve many different functions linked primarily to the maintece of
homeostasis, innate defense against pathogens, tissue repair and metabolism.
Although some of these functions appear common to all tissues, others are
specific to the homing tissue. Thus, MF become adapted to perform particular
functions in a given tissue. Accordingly, MF express common markers but also
sets of tissue-specific markers linked to dedicated functions. One of the
largest pool of MF in the body lines up the wall of the gut. Located in the
small intestine, Peyer's patches (PP) are primary antigen sampling and mucosal
immune response inductive sites. Surprisingly, although markers of intestinal
MF, such as F4/80, have been identified more than 30 years ago, MF of PP escaped
any kind of phenotypic description and remained "unknown" for decades. In
absence of MF identification, the characterization of the PP mononuclear
phagocyte system (MPS) functions has been impaired. However, taking into account
that PP are privileged sites of entry for pathogens, it is important to
understand how the latter are handled by and/or escape the PP MPS, especially
MF, which role in killing invaders is well known. This review focuses on recent
advances on the PP MPS, which have allowed, through new criteria of PP phagocyte
subset identification, the characterization of PP MF origin, diversity,
specificity, location and functions. The early replication of certain prion strains within Peyer's patches in the
small intestine is essential for the efficient spread of disease to the brain
after oral exposure. Our data show that orally acquired prions utilize
specialized gut epithelial cells known as M cells to enter Peyer's patches. M
cells express the cellular isoform of the prion protein, PrPC, and this may be
exploited by some pathogens as an uptake receptor to enter Peyer's patches. This
suggested that PrPC might also mediate the uptake and transfer of prions across
the gut epithelium into Peyer's patches in order to establish infection.
Furthermore, the expression level of PrPC in the gut epithelium could influence
the uptake of prions from the lumen of the small intestine. To test this
hypothesis, transgenic mice were created in which deficiency in PrPC was
specifically restricted to epithelial cells throughout the lining of the small
intestine. Our data clearly show that efficient prion neuroinvasion after oral
exposure occurred independently of PrPC expression in small intestinal
epithelial cells. The specific absence of PrPC in the gut epithelium did not
influence the early replication of prions in Peyer's patches or disease
susceptibility. Acute mucosal inflammation can enhance PrPC expression in the
intestine, implying the potential to enhance oral prion disease pathogenesis and
susceptibility. However, our data suggest that the magnitude of PrPC expression
in the epithelium lining the small intestine is unlikely to be an important
factor which influences the risk of oral prion disease susceptibility.IMPORTANCE
The accumulation of orally acquired prions within Peyer's patches in the small
intestine is essential for the efficient spread of disease to the brain. Little
is known of how the prions initially establish infection within Peyer's patches.
Some gastrointestinal pathogens utilize molecules, such as the cellular prion
protein PrPC, expressed on gut epithelial cells to enter Peyer's patches. Acute
mucosal inflammation can enhance PrPC expression in the intestine, implying the
potential to enhance oral prion disease susceptibility. We used transgenic mice
to determine whether the uptake of prions into Peyer's patches was dependent
upon PrPC expression in the gut epithelium. We show that orally acquired prions
can establish infection in Peyer's patches independently of PrPC expression in
gut epithelial cells. Our data suggest that the magnitude of PrPC expression in
the epithelium lining the small intestine is unlikely to be an important factor
which influences oral prion disease susceptibility. Sex differences in immunity are well described in the literature and thought to
be mainly driven by sex hormones and sex-linked immune response genes. The
gastrointestinal tract (GIT) is one of the largest immune organs in the body and
contains multiple immune cells in the GIT-associated lymphoid tissue, Peyer's
patches and elsewhere, which together have profound effects on local and
systemic inflammation. The GIT is colonised with microbial communities composed
of bacteria, fungi and viruses, collectively known as the GIT microbiota. The
GIT microbiota drives multiple interactions locally with immune cells that
regulate the homeostatic environment and systemically in diverse tissues. It is
becoming evident that the microbiota differs between the sexes, both in animal
models and in humans, and these sex differences often lead to sex-dependent
changes in local GIT inflammation, systemic immunity and susceptibility to a
range of inflammatory diseases. The sexually dimorphic microbiome has been
termed the 'microgenderome'. Herein, we review the evidence for the
microgenderome and contemplate the role it plays in driving sex differences in
immunity and disease susceptibility. We further consider the impact that
biological sex might play in the response to treatments aimed at manipulating
the GIT microbiota, such as prebiotics, live biotherapeutics, (probiotics,
synbiotics and bacteriotherapies) and faecal microbial transplant. These
alternative therapies hold potential in the treatment of both psychological
(e.g., anxiety, depression) and physiological (e.g., irritable bowel disease)
disorders differentially affecting males and females. BACKGROUND AND AIM: Peyer's patches (PPs) play a major role in intestinal
mucosal immunity; however, their role in ulcerative colitis (UC) is not well
investigated. We evaluated endoscopic features of PPs on narrow-band imaging
with magnifying endoscopy (NBI-ME) and investigated their association with
clinical factors.
METHODS: We prospectively recruited 105 patients with UC, 18 with Crohn's
disease, 16 with disease control, and 33 healthy control subjects at three
institutions from 2014 to 2017. NBI-ME images of the villi of PPs were evaluated
according to the Villi Index, and patients were divided into the Villi Index low
(L) and high (H) types. The 1-year sustained clinical remission rate was
evaluated between L-type and H-type PPs in patients with UC.
RESULTS: The proportions of patients with H-type PPs were significantly higher
among UC, Crohn's disease, and disease control patients than among healthy
control patients (P = 0.0125, 0.018, 0.0007). In UC, age, gender, endoscopic
score, and extent of disease involvement were not significantly different
between L-type and H-type PPs, whereas the sustained clinical remission rate was
significantly higher in L-type PPs than in H-type PPs (88% [57/65] vs 65%
[17/26], P = 0.019). Multivariate analysis revealed that the L type of PPs was a
significant factor for sustained clinical remission (odds ratio 3.8, 95%
confidence interval 1.1-12.9, P = 0.033).
CONCLUSIONS: Patients with UC showed endoscopic alterations in PPs on NBI-ME,
and highly altered appearance of PPs can be associated with a high risk of
clinical relapse in patients with UC. The small intestine hosts specialized lymphoid structures, the Peyer's patches,
that face the gut lumen and are overlaid with unique epithelial cells, called
microfold (M) cells. M cells are considered to constitute an important route for
antigen uptake in the mucosal immune system. Here, we used intravital microscopy
to define immune cell populations, which are in close contact with M cells and
potentially sample antigen. We present live evidence that DCs enter M cell
pockets and highlight the abundance of mononuclear phagocytes in these
structures. Taking advantage of the respective reporter animals, we focused on
classical DCs that express Zbtb46 and analyzed how these cells interact with M
cells in steady state and sample antigen for T cell activation in the Peyer's
patches following challenge. Peyer's patches are gut-associated lymphoid tissue located throughout the
intestinal wall. Peyer's patches consist of highly organized ovoid-shaped
follicles, classified as non-encapsulated lymphatic tissues, populated with B
cells, T cells, macrophages, and dendritic cells and function as an organism's
intestinal surveillance. Limited work compares the gene profiles of Peyer's
patches derived from different intestinal regions. In the current study, we
first performed whole transcriptome analysis using RNAseq to compare duodenal
and ileal Peyer's patches obtained from the small intestine of Long Evans rats.
Of the 12,300 genes that were highly expressed, 18.5% were significantly
different between the duodenum and ileum. Using samples obtained from additional
subjects (n = 10), we validated the novel gene expression patterns in Peyer's
patches obtained from the three regions of the small intestine. Rats had a
significantly reduced number of Peyer's patches in the duodenum in comparison to
either the jejunum or ileum. Regional differences in structural, metabolic, and
immune-related genes were validated. Genes such as alcohol dehydrogenase 1, gap
junction protein beta 2, and serine peptidase inhibitor clade b, member 1a were
significantly reduced in the ileum in comparison to other regions. On the other
hand, genes such as complement C3d receptor type, lymphocyte cytosolic protein
1, and lysozyme C2 precursor were significantly lower in the duodenum. In
summary, the gene expression pattern of Peyer's patches is influenced by
intestinal location and may contribute to its role in that segment. |
Is tofacitinib a JAK inhibitor? | Yes, tofacitinib is a small JAK inhibitor. | Several cytokines signalling via Janus Kinase (JAK) proteins have been
implicated in the pathogenesis of immune-mediated inflammatory diseases,
including psoriasis and rheumatoid arthritis (RA). Tofacitinib, a small JAK
inhibitor, is approved for the treatment of RA and has demonstrated good
efficacy in psoriasis phase III clinical trials. In this work, we analysed the
in vitro effects of tofacitinib on the functions of human dendritic cells (DCs)
and macrophages. When assessing the effects of tofacitinib on monocyte-derived
DCs, we observed reduced differentiation of monocytes into immature DCs, as
evidenced by a decreased transcription of CD209 and CD80. Phenotype assessment
in the presence of tofacitinib suggested a switch towards a M1-like macrophage
phenotype, as evidenced by the expression of M1 markers such as iNOS, as well as
cytokines typically expressed by M1 cells, including IL-12 and IL-23. Of note,
Arginase1 and CD200R, typically expressed by M2 cells, were absent on
tofacitinib-treated DCs. Furthermore, tofacitinib affected the response of
differentiated DCs to maturation stimuli such as LPS and IFNγ, resulting in a
partial up-regulation of IL-23 and down-regulation of IL-12, as assessed by
qPCR. When investigating macrophage development, we found that tofacitinib
inhibited the ability of monocytes to differentiate and polarize into regulatory
M2 macrophages, while rather enhancing the ability to develop into inflammatory
M1-like macrophages, as evidenced by decreased expression of the M2 marker
CD200R and enhanced production of IL-12 and IL-23. In conclusion, tofacitinib
impacts the differentiation of human DCs and macrophages, it particularly
favours generation of M1-like pro-inflammatory macrophages. |
Describe the GenomeAsia 100K Project | The GenomeAsia 100K Project (GenomeAsia100K Project) aims to identify and catalogue genetic variation, population structure, disease associations and founder effects in populations across Asia and worldwide. It includes a whole-genome sequencing reference dataset from 1,739 individuals of 219 population groups and 64 countries across Asia, as well as a population-wide association dataset. | The underrepresentation of non-Europeans in human genetic studies so far has
limited the diversity of individuals in genomic datasets and led to reduced
medical relevance for a large proportion of the world's population.
Population-specific reference genome datasets as well as genome-wide association
studies in diverse populations are needed to address this issue. Here we
describe the pilot phase of the GenomeAsia 100K Project. This includes a
whole-genome sequencing reference dataset from 1,739 individuals of 219
population groups and 64 countries across Asia. We catalogue genetic variation,
population structure, disease associations and founder effects. We also explore
the use of this dataset in imputation, to facilitate genetic studies in
populations across Asia and worldwide. |
Which disease is treated with Risdiplam? | Risdiplam is approved for spinal muscular atrophy. | SMA is an inherited disease that leads to loss of motor function and ambulation
and a reduced life expectancy. We have been working to develop orally
administrated, systemically distributed small molecules to increase levels of
functional SMN protein. Compound 2 was the first SMN2 splicing modifier tested
in clinical trials in healthy volunteers and SMA patients. It was safe and well
tolerated and increased SMN protein levels up to 2-fold in patients.
Nevertheless, its development was stopped as a precautionary measure because
retinal toxicity was observed in cynomolgus monkeys after chronic daily oral
dosing (39 weeks) at exposures in excess of those investigated in patients.
Herein, we describe the discovery of 1 (risdiplam, RG7916, RO7034067) that
focused on thorough pharmacology, DMPK and safety characterization and
optimization. This compound is undergoing pivotal clinical trials and is a
promising medicine for the treatment of patients in all ages and stages with
SMA. AIMS: Risdiplam (RG7916, RO7034067) is an orally administered, centrally and
peripherally distributed, survival of motor neuron 2 (SMN2) mRNA splicing
modifier for the treatment of spinal muscular atrophy (SMA). The objectives of
this entry-into-human study were to assess the safety, tolerability,
pharmacokinetics (PK) and pharmacodynamics of risdiplam, and the effect of the
strong CYP3A inhibitor itraconazole on the PK of risdiplam in healthy male
volunteers.
METHODS: Part 1 had a randomized, double-blind, adaptive design with 25 subjects
receiving single ascending oral doses of risdiplam (ranging from 0.6-18.0 mg,
n = 18) or placebo (n = 7). A Bayesian framework was applied to estimate
risdiplam's effect on SMN2 mRNA. The effect of multiple doses of itraconazole on
the PK of risdiplam was also assessed using a two-period cross-over design
(n = 8).
RESULTS: Risdiplam in the fasted or fed state was well tolerated. Risdiplam
exhibited linear PK over the dose range with a multi-phasic decline with a mean
terminal half-life of 40-69 h. Food had no relevant effect, and itraconazole had
only a minor effect on plasma PK indicating a low fraction of risdiplam
metabolized by CYP3A. The highest tested dose of 18.0 mg risdiplam led to
approximately 41% (95% confidence interval 27-55%) of the estimated maximum
increase in SMN2 mRNA.
CONCLUSIONS: Risdiplam was well tolerated and proof of mechanism was
demonstrated by the intended shift in SMN2 splicing towards full-length SMN2
mRNA. Based on these data, Phase 2/3 studies of risdiplam in patients with SMA
are now ongoing. Risdiplam (Evrysdi™) is an orally administered, survival motor neuron 2
(SMN2)-directed RNA splicing modifier being developed by Roche, PTC Therapeutics
Inc and the SMA Foundation for the treatment of the spinal muscular atrophy. The
small molecule is designed to treat spinal muscular atrophy caused by mutations
in chromosome 5q leading to SMN protein deficiency. The drug boosts the ability
of an alternative gene SMN2 to produce full-length and functional SMN protein.
In August 2020, Evrysdi™ (risdiplam) received its first approval in the USA for
the treatment of spinal muscular atrophy in patients 2 months of age and older.
Risdiplam is in pre-registration for this indication in numerous countries
worldwide, including the European Union, Brazil, Chile, China, Indonesia,
Russia, South Korea and Taiwan. This article summarizes the milestones in the
development of risdiplam leading to this first approval for spinal muscular
atrophy. The phenotype of spinal muscular atrophy (SMA) has been changing with the recent
availability of three FDA-approved treatments: intrathecal nusinersen,
intravenous onasemnogene abeparvovec-xioi, and enteral risdiplam. The degree of
improvement in muscle strength and respiratory health varies with SMA genotype,
severity of baseline neuromuscular and pulmonary impairment, medication used,
and timing of the first dose. A spectrum of pulmonary outcomes has been reported
with these novel medications when used early and in conjunction with proactive
multidisciplinary management of comorbidities. In this review, we summarize the
reported impact of these novel therapies on pulmonary well-being and the
improving trajectory of pulmonary morbidity, compared to the natural history of
SMA. The importance of ongoing clinical monitoring albeit the improved phenotype
is reiterated. We also discuss the limitations of the current SMA-therapy trials
and offer suggestions for future clinical-outcome studies and long-term
monitoring. OBJECTIVE: Evaluation of ophthalmologic safety with focus on retinal safety in
patients with spinal muscular atrophy (SMA) treated with risdiplam (EVRYSDI®), a
survival of motor neuron 2 splicing modifier associated with retinal toxicity in
monkeys. Risdiplam was approved recently for the treatment of patients with SMA,
aged ≥ 2 months in the United States, and is currently under Health Authority
review in the EU.
METHODS: Subjects included patients with SMA aged 2 months-60 years enrolled in
the FIREFISH, SUNFISH, and JEWELFISH clinical trials for risdiplam.
Ophthalmologic assessments, including functional assessments (age-appropriate
visual acuity and visual field) and imaging (spectral domain optical coherence
tomography [SD-OCT], fundus photography, and fundus autofluorescence [FAF]),
were conducted at baseline and every 2-6 months depending on study and
assessment. SD-OCT, FAF, fundus photography, and threshold perimetry were
evaluated by an independent, masked reading center. Adverse events (AEs) were
reported throughout the study.
RESULTS: A total of 245 patients receiving risdiplam were assessed.
Comprehensive, high-quality, ophthalmologic monitoring assessing retinal
structure and visual function showed no retinal structural or functional
changes. In the youngest patients, SD-OCT findings of normal retinal maturation
were observed. AEs involving eye disorders were not suggestive of
risdiplam-induced toxicity and resolved with ongoing treatment.
INTERPRETATION: Extensive ophthalmologic monitoring conducted in studies in
patients with SMA confirmed that risdiplam does not induce ophthalmologic
toxicity in pediatric or adult patients with SMA at the therapeutic dose. These
results suggest that safety ophthalmologic monitoring is not needed in patients
receiving risdiplam, as also reflected in the United States Prescribing
Information for risdiplam. Recent advances in our understanding of RNA biology have uncovered crucial roles
for RNA in multiple disease states, ranging from viral and bacterial infections
to cancer and neurological disorders. As a result, multiple laboratories have
become interested in developing drug-like small molecules to target RNA.
However, this development comes with multiple unique challenges. For example,
RNA is inherently dynamic and has limited chemical diversity. In addition,
promiscuous RNA-binding ligands are often identified during screening campaigns.
This Tutorial Review overviews important considerations and advancements for
generating RNA-targeted small molecules, ranging from fundamental chemistry to
promising small molecule examples with demonstrated clinical efficacy.
Specifically, we begin by exploring RNA functional classes, structural
hierarchy, and dynamics. We then discuss fundamental RNA recognition principles
along with methods for small molecule screening and RNA structure determination.
Finally, we review unique challenges and emerging solutions from both the RNA
and small molecule perspectives for generating RNA-targeted ligands before
highlighting a selection of the "Greatest Hits" to date. These molecules target
RNA in a variety of diseases, including cancer, neurodegeneration, and viral
infection, in cellular and animal model systems. Additionally, we explore the
recently FDA-approved small molecule regulator of RNA splicing, risdiplam, for
treatment of spinal muscular atrophy. Together, this Tutorial Review showcases
the fundamental role of chemical and molecular recognition principles in
enhancing our understanding of RNA biology and contributing to the rapidly
growing number of RNA-targeted probes and therapeutics. In particular, we hope
this widely accessible review will serve as inspiration for aspiring small
molecule and/or RNA researchers. BACKGROUND: Type 1 spinal muscular atrophy is a rare, progressive neuromuscular
disease that is caused by low levels of functional survival of motor neuron
(SMN) protein. Risdiplam is an orally administered, small molecule that modifies
SMN2 pre-messenger RNA splicing and increases levels of functional SMN protein.
METHODS: We report the results of part 1 of a two-part, phase 2-3, open-label
study of risdiplam in infants 1 to 7 months of age who had type 1 spinal
muscular atrophy, which is characterized by the infant not attaining the ability
to sit without support. Primary outcomes were safety, pharmacokinetics,
pharmacodynamics (including the blood SMN protein concentration), and the
selection of the risdiplam dose for part 2 of the study. Exploratory outcomes
included the ability to sit without support for at least 5 seconds.
RESULTS: A total of 21 infants were enrolled. Four infants were in a low-dose
cohort and were treated with a final dose at month 12 of 0.08 mg of risdiplam
per kilogram of body weight per day, and 17 were in a high-dose cohort and were
treated with a final dose at month 12 of 0.2 mg per kilogram per day. The
baseline median SMN protein concentrations in blood were 1.31 ng per milliliter
in the low-dose cohort and 2.54 ng per milliliter in the high-dose cohort; at 12
months, the median values increased to 3.05 ng per milliliter and 5.66 ng per
milliliter, respectively, which represented a median of 3.0 times and 1.9 times
the baseline values in the low-dose and high-dose cohorts, respectively. Serious
adverse events included pneumonia, respiratory tract infection, and acute
respiratory failure. At the time of this publication, 4 infants had died of
respiratory complications. Seven infants in the high-dose cohort and no infants
in the low-dose cohort were able to sit without support for at least 5 seconds.
The higher dose of risdiplam (0.2 mg per kilogram per day) was selected for part
2 of the study.
CONCLUSIONS: In infants with type 1 spinal muscular atrophy, treatment with oral
risdiplam led to an increased expression of functional SMN protein in the blood.
(Funded by F. Hoffmann-La Roche; ClinicalTrials.gov number, NCT02913482.). Not too long ago, the concept of selectively targeting mRNA with small molecules
was perceived as a formidable scientific challenge. The discovery of small
molecule splicing modifiers and the development of risdiplam for the treatment
of spinal muscular atrophy (SMA) have firmly established proof of concept for
this exciting new platform and transformed a scientific curiosity into a viable
technology to target disease. Today, several approaches to target mRNA with
small molecules, supported by biophysical and screening methods, are in place to
deliver new drugs with high therapeutic relevance. Risdiplam is the first approved small-molecule splicing modulator for the
treatment of spinal muscular atrophy (SMA). Previous studies demonstrated that
risdiplam analogues have two separate binding sites in exon 7 of the SMN2
pre-mRNA: (i) the 5'-splice site and (ii) an upstream purine (GA)-rich binding
site. Importantly, the sequence of this GA-rich binding site significantly
enhanced the potency of risdiplam analogues. In this report, we unambiguously
determined that a known risdiplam analogue, SMN-C2, binds to single-stranded
GA-rich RNA in a sequence-specific manner. The minimum required binding sequence
for SMN-C2 was identified as GAAGGAAGG. We performed all-atom simulations using
a robust Gaussian accelerated molecular dynamics (GaMD) method, which captured
spontaneous binding of a risdiplam analogue to the target nucleic acids. We
uncovered, for the first time, a ligand-binding pocket formed by two sequential
GAAG loop-like structures. The simulation findings were highly consistent with
experimental data obtained from saturation transfer difference (STD) NMR and
structure-affinity-relationship studies of the risdiplam analogues. Together,
these studies illuminate us to understand the molecular basis of single-stranded
purine-rich RNA recognition by small-molecule splicing modulators with an
unprecedented binding mode. INTRODUCTION/AIMS: There are currently three medications approved for spinal
muscular atrophy (SMA), but the use of these medications in combination has not
been well described.
METHODS: This is a retrospective report of four cases of SMA treated with dual
onasemnogene and risdiplam therapy at our institution.
RESULTS: Following onasemnogene therapy, all four patients experienced a
perceived plateau of therapeutic benefit, at which time daily risdiplam was
started. Transient fatigue and weakness was seen in two patients following
risdiplam initiation, but this resolved within 1 mo. One patient was
hospitalized with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)
and post-viral pneumonia, weeks following risdiplam initiation. No other adverse
effects related to onasemnogene and risdiplam combination therapy were
identified and all patients experienced objective and subjective improvement.
DISCUSSION: Combination therapy with onasemnogene and risdiplam in patients with
SMA appears to be well-tolerated. Further large prospective trials are needed to
determine whether dual therapy is more efficacious than monotherapy, and to
identify rare adverse events that may occur with the use of combination therapy. Risdiplam (Evrysdi) improves motor neuron function in patients with spinal
muscular atrophy (SMA) and has been approved for the treatment of patients
≥2 months old. Risdiplam exhibits time-dependent inhibition of cytochrome P450
(CYP) 3A in vitro. While many pediatric patients receive risdiplam, a drug-drug
interaction (DDI) study in pediatric patients with SMA was not feasible.
Therefore, a novel physiologically-based pharmacokinetic (PBPK) model-based
strategy was proposed to extrapolate DDI risk from healthy adults to children
with SMA in an iterative manner. A clinical DDI study was performed in healthy
adults at relevant risdiplam exposures observed in children. Risdiplam caused an
1.11-fold increase in the ratio of midazolam area under the curve with and
without risdiplam (AUCR)), suggesting an 18-fold lower in vivo CYP3A
inactivation constant compared with the in vitro value. A pediatric PBPK model
for risdiplam was validated with independent data and combined with a validated
midazolam pediatric PBPK model to extrapolate DDI from adults to pediatric
patients with SMA. The impact of selected intestinal and hepatic CYP3A
ontogenies on the DDI susceptibility in children relative to adults was
investigated. The PBPK analysis suggests that primary CYP3A inhibition by
risdiplam occurs in the intestine rather than the liver. The PBPK-predicted
risdiplam CYP3A inhibition risk in pediatric patients with SMA aged
2 months-18 years was negligible (midazolam AUCR of 1.09-1.18) and included in
the US prescribing information of risdiplam. Comprehensive evaluation of the
sensitivity of predicted CYP3A DDI on selected intestinal and hepatic CYP3A
ontogeny functions, together with PBPK model-based strategy proposed here, aim
to guide and facilitate DDI extrapolations in pediatric populations. Spinal muscular atrophy (SMA) is caused by the loss of the survival motor neuron
1 (SMN1) gene function. The related SMN2 gene partially compensates but produces
insufficient levels of SMN protein due to alternative splicing of exon 7.
Evrysdi™ (risdiplam), recently approved for the treatment of SMA, and related
compounds promote exon 7 inclusion to generate full-length SMN2 mRNA and
increase SMN protein levels. SMNΔ7 type I SMA mice survive without treatment for
~17 days. SMN2 mRNA splicing modulators increase survival of SMN∆7 mice with
treatment initiated at postnatal day 3 (PND3). To define SMN requirements for
adult mice, SMNΔ7 mice were dosed with an SMN2 mRNA splicing modifier from PND3
to PND40, then dosing was stopped. Mice not treated after PND40 showed
progressive weight loss, necrosis, and muscle atrophy after ~20 days. Male mice
presented a more severe phenotype than female mice. Mice dosed continuously did
not show disease symptoms. The estimated half-life of SMN protein is 2 days
indicating that the SMA phenotype reappeared after SMN protein levels returned
to baseline. Although SMN protein levels decreased with age in mice and SMN
protein levels were higher in brain than in muscle, our studies suggest that SMN
protein is required throughout the life of the mouse and is especially essential
in adult peripheral tissues including muscle. These studies indicate that drugs
such as risdiplam will be optimally therapeutic when given as early as possible
after diagnosis and potentially will be required for the life of an SMA patient. Spinal muscular atrophy (SMA) is one of the leading causes of death in infants
related to the degeneration of neurons. Currently, there are no curative
treatment options for SMA, and many options available may not be feasible. This
review presents the background, clinical studies, and indications for the use of
Risdiplam in treating SMA. SMA causes a decrease in the production of survival
motor neuron proteins (SMN) and current treatments target to increase the
expression of SMN. Risdiplam is the first and only oral medication to be
approved to treat SMA. As an SMN2 splicing modifier, it has provided stronger
systemic therapies than previous intrathecal and gene replacement therapies.
There have been many efforts to treat SMA with multidisciplinary approaches.
These include intrathecal injections to gene replacement therapies. However,
these have been faced with limitations such as reaching a good therapeutic dose
in systemic tissues, route of administration, and price. Risdiplam is currently
the only orally administered drug approved by the FDA for the treatment of SMA.
It not only provides a good therapeutic window to systemic tissues but allows
for a non-invasive approach in infants. Further investigation and comparison on
the safety profile of Risdiplam due to its broader systemic effect should be
considered with other available therapies. Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease
caused by homozygous deletions or mutations in survival motor neuron gene 1
(SMN1). Currently, the primary therapeutic strategy for SMA is to increase the
level of SMN via correcting SMN2 splicing (nusinersen and risdiplam). However,
some patients with SMA do not respond to such treatments, thereby warranting a
need to develop new therapeutic strategies. We have previously reported that
SMN2 expression is epigenetically regulated by DNA methylation levels of the
SMN2 promoter region. In the present study, we determined that
methyl-CpG-binding protein 2 (MeCP2) may bind to this critical promoter region
(nt-167 to 43). Antisense oligonucleotides (ASO-P1 and ASO-P2) were designed to
target the key methylation sites in the SMN2 promoter region, which enhanced the
overall transcription and functional protein expression levels in the SMA cell
lines. These results were similar to those observed in nusinersen-treated SMA
cells. Moreover, a combined treatment of ASO-P1 and ASO-NUS in SMA cell lines
further increases fl-SMN2 transcript and SMN protein levels. The delivery of
ASO-P1 to the central nervous system of severe SMA mice corrected the molecular,
pathological, and functional phenotypes of this disease and increased survival
rates. Our findings suggest that the key methylation regions in the SMN2
promoter region may be a novel therapeutic target for SMA. |
What is protein palmitoylation? | Protein S-palmitoylation, the covalent lipid modification of the side chain of Cys residues with the 16‑carbon fatty acid palmitate, is the most common acylation, and it enhances the membrane stability of ion channels. This post-translational modification (PTM) determines a functional mechanism of ion channel life cycle from maturation and membrane trafficking to localization. | Rho GTPases play central roles in a wide variety of cellular processes,
including cytoskeletal dynamics, cell adhesion and cell polarity. RhoU and RhoV
are Rho GTPases that have some atypical properties compared with classical Rho
family members, such as the presence of N- and C-terminal extension regions,
unusual GDP/GTP cycling and post-translational modification by palmitoylation
but not prenylation. Their activity and localization is regulated by the
N-terminal and C-terminal regions, and so far no GEFs or GAPs have been
identified for them. Similar to Rac and Cdc42, they interact with PAK
serine/threonine kinases, and in the case of PAK4, this interaction leads to
RhoU protein stabilization. In cells, RhoU and RhoV alter cell shape and cell
adhesion, which probably underlies some of the phenotypes reported for these
proteins in vivo, for example in heart development and epithelial morphogenesis.
However, the molecular basis for these functions of RhoU and RhoV remains to be
characterized. Palmitoylation (S-acylation) is the reversible conjugation of a fatty acid
(usually C16 palmitate) to intracellular cysteine residues of proteins via a
thioester linkage. Palmitoylation anchors intracellular regions of proteins to
membranes because the palmitoylated cysteine is recruited to the lipid bilayer.
NCX1 is palmitoylated at a single cysteine in its large regulatory intracellular
loop. The presence of an amphipathic α-helix immediately adjacent to the NCX1
palmitoylation site is required for NCX1 palmitoylation. The NCX1 palmitoylation
site is conserved through most metazoan phlya. Although palmitoylation does not
regulate the normal forward or reverse ion transport modes of NCX1, NCX1
palmitoylation is required for its inactivation: sodium-dependent inactivation
and inactivation by PIP2 depletion are significantly impaired for
unpalmitoylatable NCX1. Here we review the role of palmitoylation in regulating
NCX1 activity, and highlight future questions that must be addressed to fully
understand the importance of this regulatory mechanism for sodium and calcium
transport in cardiac muscle. Protein S-palmitoylation is an important post-translational modification (PTM)
in blood stages of the malaria parasite, Plasmodium falciparum. S-palmitoylation
refers to reversible covalent modification of cysteine residues of proteins by
saturated fatty acids. In vivo, palmitoylation is regulated by concerted
activities of DHHC palmitoyl acyl transferases (DHHC PATs) and acyl protein
thioesterases (APTs), which are enzymes responsible for protein palmitoylation
and depalmitoylation, respectively. Here, we investigate the role of protein
palmitoylation in red blood cell (RBC) invasion by P. falciparum merozoites. We
demonstrate for the first time that free merozoites require PAT activity for
microneme secretion in response to exposure to the physiologically relevant low
[K+] environment, characteristic of blood plasma. We have adapted copper
catalyzed alkyne azide chemistry (CuAAC) to image palmitoylation in merozoites
and found that exposure to low [K+] activates PAT activity in merozoites.
Moreover, using acyl biotin exchange chemistry (ABE) and confocal imaging, we
demonstrate that a calcium dependent protein kinase, PfCDPK1, an essential
regulator of key invasion processes such as motility and microneme secretion,
undergoes dynamic palmitoylation and localizes to the merozoite membrane.
Treatment of merozoites with the PAT inhibitor, 2-bromopalmitate (2-BP),
effectively inhibits microneme secretion and RBC invasion by the parasite, thus
opening the possibility of targeting P. falciparum PATs for antimalarial drug
discovery to inhibit blood stage growth of malaria parasites. |
Αre plants from the genus Strychnos the original source of curare? | Species of plants from the genus Strychnos are the source of curare. | The history to about 1850 of the muscle-relaxant poison curare is discussed,
especially the developments leading to the botanical identification of the
plants that yield the alkaloidal active principles: Loganiaceae (Strychnos
species) and Menispermaceae (Abuta, Chondrodendron, and Curarea species). One of
the earliest encounters with the poison appears to have been during the
exploration of the Lake Maracaibo region in Colombia by Alonso Pérez de Tolosa
in 1548. It is pointed out (yet again) that Sir Walter Ralegh did not bring back
the poison to Europe in 1595 and that it was Keymis who first came across the
word ourari when exploring the lower reaches of the Orinoco in 1596. Gumilla, La
Condamine, Ulloa, Veigl, and others gave much additional information about the
poison during the 18th century. Scientific studies began in the latter part of
the century when Schreber listed the botanical identities of four of the plant
components entering into the curare prepared by the Akawai Indians of Surinam.
As far as is known, none of these people actually saw curare being made.
Thereafter, progress was rapid. Humboldt and Bonpland were the first trained
scientists to witness the preparation of the poison, at the very beginning of
the 19th century. Subsequent exploration by Martius and Spix, Poeppig, Youd, the
Schomburgk brothers, De Castelnau and Deville, Spruce, and others, up to the
middle of the century, extended and deepened botanical and ethnological
knowledge of curare. Study of its physiology started at about that time with the
classical experiments of Rudolf von Koelliker and Claude Bernard. The ethnobotanical uses of South American species of Strychnos L. (Loganiaceae)
are reviewed, with the exception of their major rôle in the preparation of
curare, which will be dealt with in detail elsewhere. Medicinal uses are less
common than is the case with the African and Asian species of the genus. About
140 samples, mostly of leaves, belonging to 53 species, have been screened for
alkaloids. As with species from other parts of the world, the stem bark and root
bark tend to be a richer source than leaves. Nor-harman is present in extracts
from S. barnhartiana leaves. Pyridino-indolo-quinolizidinone (angustine-type)
bases are also found in several species. The occurrence and pharmacology of the
(non-curarizing) alkaloids known to be present in South American Strychnos
species is reviewed. |
When was galcanezumab approved by FDA? | Galcanezumab was approved by the FDA in September 2018. | Monoclonal antibodies against calcitonin gene-related peptide (CGRP) or its
receptor (CLR + RAMP1) offer considerable improvements over existing drugs in
migraine prophylaxis and are the first designed to act on the trigeminal pain
system. Erenumab is approved by the FDA and EMA and has reached the market since
May 2018. Two antibodies, fremanezumab and galcanezumab, directed towards the
CGRP ligand, were approved by the FDA in September 2018. To view this Bench to
Bedside, open or download the PDF. |
Are variants in FHF2 (also known as FGF13) associated with encephalopathy? | Yes. FHF2 (also known as FGF13) variants are a cause of infantile-onset developmental and epileptic encephalopathy. | Author information:
(1)Institute of Medical Genetics, University Hospital of Wales, Cardiff CF14
4XW, UK; Division of Cancer and Genetics, School of Medicine, Cardiff
University, Cardiff CF14 4XN, UK. Electronic address: [email protected].
(2)Department of Biological Sciences, Hunter College of City University, 695
Park Avenue, New York, NY 10065, USA; Program in Biology, Graduate Center of
City University, 365 Fifth Avenue, New York, NY 10016, USA.
(3)Neurology and Molecular Neuroscience Research, Institute of Life Science,
Swansea University Medical School, Swansea University, Swansea SA2 8PP, UK.
(4)Neurology and Molecular Neuroscience Research, Institute of Life Science,
Swansea University Medical School, Swansea University, Swansea SA2 8PP, UK;
Neurology department, Morriston Hospital, Swansea Bay University Hospital Health
Board, Swansea SA6 6NL, UK.
(5)Paediatric Neurology, University Hospital of Wales, Heath Park, Cardiff CF14
4XW, UK.
(6)Division of Cancer and Genetics, School of Medicine, Cardiff University,
Cardiff CF14 4XN, UK.
(7)Institute of Medical Genetics, University Hospital of Wales, Cardiff CF14
4XW, UK.
(8)Manchester Centre for Genomic Medicine, Manchester University NHS Foundation
Trust and Institute of Human Development, University of Manchester, Manchester
M13 9WL, UK.
(9)Department of Paediatric Neurology, Royal Manchester Children's Hospital,
Oxford Road, Manchester M13 9WL, UK.
(10)Department of Neurology, Salford Royal Hospital NHS Foundation Trust, Stott
Lane, Salford M6 8HD, UK.
(11)Department of Radiology, Alder Hey Children's NHS Foundation Trust, Eaton
Road, Liverpool L12 2AP, UK.
(12)West Midlands Regional Genetics Service, Clinical Genetics Unit, Birmingham
Women's Hospital, Birmingham B15 2TG, UK.
(13)Department of Paediatrics, McMaster University, 1200 Main St. W., Hamilton,
ON L8N 3Z5, Canada.
(14)Department of Pediatrics, Peking University First Hospital, Xicheng
District, Beijing 100034, China.
(15)Cipher Gene Ltd, Beijing, China.
(16)Genomics England, London EC1M 6BQ, UK.
(17)Neurology and Molecular Neuroscience Research, Institute of Life Science,
Swansea University Medical School, Swansea University, Swansea SA2 8PP, UK;
Faculty of Medicine and Health, Camperdown, University of Sydney, NSW 2006,
Australia.
(18)Neurology and Molecular Neuroscience Research, Institute of Life Science,
Swansea University Medical School, Swansea University, Swansea SA2 8PP, UK; Kids
Neuroscience Centre, Kids Research, Children Hospital at Westmead, Sydney, NSW
2145, Australia; Brain and Mind Centre, Faculty of Medicine and Health,
University of Sydney, NSW 2050, Australia. |
Tofersen has been developed for treatment of which disease? | Tofersen is an antisense oligonucleotide that mediates the degradation of superoxide dismutase 1 (SOD1) messenger RNA to reduce SOD1 protein synthesis is being studied for the treatment of amyotrophic lateral sclerosis due to SOD1 mutations. | BACKGROUND: Tofersen is an antisense oligonucleotide that mediates the
degradation of superoxide dismutase 1 (SOD1) messenger RNA to reduce SOD1
protein synthesis. Intrathecal administration of tofersen is being studied for
the treatment of amyotrophic lateral sclerosis (ALS) due to SOD1 mutations.
METHODS: We conducted a phase 1-2 ascending-dose trial evaluating tofersen in
adults with ALS due to SOD1 mutations. In each dose cohort (20, 40, 60, or 100
mg), participants were randomly assigned in a 3:1 ratio to receive five doses of
tofersen or placebo, administered intrathecally for 12 weeks. The primary
outcomes were safety and pharmacokinetics. The secondary outcome was the change
from baseline in the cerebrospinal fluid (CSF) SOD1 concentration at day 85.
Clinical function and vital capacity were measured.
RESULTS: A total of 50 participants underwent randomization and were included in
the analyses; 48 participants received all five planned doses. Lumbar
puncture-related adverse events were observed in most participants. Elevations
in CSF white-cell count and protein were reported as adverse events in 4 and 5
participants, respectively, who received tofersen. Among participants who
received tofersen, one died from pulmonary embolus on day 137, and one from
respiratory failure on day 152; one participant in the placebo group died from
respiratory failure on day 52. The difference at day 85 in the change from
baseline in the CSF SOD1 concentration between the tofersen groups and the
placebo group was 2 percentage points (95% confidence interval [CI], -18 to 27)
for the 20-mg dose, -25 percentage points (95% CI, -40 to -5) for the 40-mg
dose, -19 percentage points (95% CI, -35 to 2) for the 60-mg dose, and -33
percentage points (95% CI, -47 to -16) for the 100-mg dose.
CONCLUSIONS: In adults with ALS due to SOD1 mutations, CSF SOD1 concentrations
decreased at the highest concentration of tofersen administered intrathecally
over a period of 12 weeks. CSF pleocytosis occurred in some participants
receiving tofersen. Lumbar puncture-related adverse events were observed in most
participants. (Funded by Biogen; ClinicalTrials.gov number, NCT02623699; EudraCT
number, 2015-004098-33.). |
What is the cause of lactose intolerance? | Lactose intolerance is a common condition caused by lactase deficiency and may result in symptoms of lactose malabsorption (bloating, flatulence, abdominal discomfort, and change in bowel habits).
Four clinical subtypes of lactose intolerance may be distinguished, namely lactase deficiency in premature infants, congenital lactase deficiency, adult-type hypolactasia and secondary lactase intolerance. | Lactose intolerance is a common condition caused by lactase deficiency and may
result in symptoms of lactose malabsorption (bloating, flatulence, abdominal
discomfort, and change in bowel habits). As current data is limited, the aim of
our study was to assess the efficacy of probiotics with a β-galactosidase
activity on symptoms of lactose malabsorption and on the lactose hydrogen breath
test (LHBT). The study group comprised eight symptomatic female patients with a
positive LHBT. Patients were treated for 6 months with a probiotic formula with
β-galactosidase activity (Bio-25, Ambrosia-SupHerb, Israel). All patients
completed a demographic questionnaire as well as a diary for the assessment of
symptom severity and frequency at entry, every 8 weeks, and at the end of the
treatment period. Measurements of hydrogen (H2) levels (parts per million, ppm)
at each of these time points were also performed. End points were a decrease of
50% in symptom severity or frequency, and the normalization (decrease below
cutoff point of 20 ppm) of the breath test. Mean age and mean body mass index
(BMI) were 36.4 ± 18.6 years and 23.2 kg/m2, respectively. Compared to baseline
scores, the frequency of most symptoms, and the severity of bloating and
flatulence, improved after treatment. Normalization of LHBT was obtained in only
two patients (25%). In this pilot study, Bio-25, a unique formulation of
probiotics with β-galactosidase activity, demonstrated symptom resolution in
most patients with lactose malabsorption. A larger randomized trial is warranted
to confirm these preliminary findings. INTRODUCTION: Adult lactose intolerance (ALI) significantly alters calcium
intake and absorption, and thus may promote osteoporosis. ALI is a recessive
condition with a geographical north-south gradient characterised by decreased
levels of intestinal lactase. PCR-based genotyping of lactase (LCT) gene
polymorphisms is a safe and easy way to diagnose ALI and may complement
diagnostic procedures to identify individuals at risk for reduced calcium intake
and subsequently osteoporosis due to lactose malabsorption. Therefore, we
investigated the frequency of ALI and its influence on calcium intake, markers
of bone metabolism and bone mineral density (BMD) in a cohort of Turkish
immigrants living in Germany.
MATERIALS AND METHODS: We investigated single nucleotide polymorphisms of the
LCT gene, calcium intake, markers of bone metabolism and BMD in 183 Turkish
immigrants.
RESULTS: ALI was diagnosed in 154 out of 183 (81%) probands. ALI was
significantly associated with self-reported lactose intolerance (p < 0.001) and
dislike for dairy products (p < 0.01). Osteopenia was diagnosed in 59 out of 183
(32%) and osteoporosis in 15 out of 183 (8%) probands. Probands with reduced BMD
had ALI in 86%. All probands had a decreased calcium intake [mg/week]. There was
no significant association between ALI, calcium intake, markers of bone
metabolism or BMD.
CONCLUSION: Turkish immigrants mostly have ALI and overall show a reduced
calcium intake per week. However, ALI did not significantly influence calcium
intake, markers of bone metabolism or BMD in this cohort. Therefore, ALI in
Turkish immigrants does not seem to be a risk factor for osteoporosis. Dairy products have been a key component of dietary guidance in the United
States for more than 100 years. In light of major advances in the understanding
of dietary intake and metabolism, the aim of this review was to examine whether
dairy should remain a single commodity in federal guidance. Considerations
include recognizing that a substantial proportion of the world's adult
population (65%-70%) exhibits lactase nonpersistence, a reduced ability to
metabolize lactose to glucose and galactose. Shifts in the US population,
including a greater proportion of African Americans and Asians, are of key
importance because several studies have shown a markedly higher prevalence of
lactase nonpersistence and, consequently, a lower dairy intake among these
groups. While cow's milk alternatives are available, families who use them will
pay up to an additional $1400 per year compared with those who are able to
consume dairy products. Dietary guidance also contains downstream effects for
government assistance, such as the US Department of Agriculture's National
School Lunch Program and School Breakfast Program. For reasons like these,
Canada has recently removed dairy as a separate food group in national dietary
guidance. The results of the present review suggest that consideration of this
modification when developing population-level guidelines in the United States is
warranted. Lactose is a reducing sugar consisting of galactose and glucose, linked by a β
(1→4) glycosidic bond, considered as an antioxidant due to its α-hydroxycarbonyl
group. Lactose is widely ingested through the milk and other unfermented dairy
products and is considered to be one of the primary foods. On the other hand,
lactose is also considered as one of the most widely used excipients for the
development of pharmaceutical formulations. In this sense, lactose has been
related to numerous drug-excipient or drug-food pharmacokinetic interactions.
Intolerance, maldigestion and malabsorption of carbohydrates are common
disorders in clinical practice, with lactose-intolerance being the most
frequently diagnosed, afflicting 10% of the world's population. Four clinical
subtypes of lactose intolerance may be distinguished, namely lactase deficiency
in premature infants, congenital lactase deficiency, adult-type hypolactasia and
secondary lactase intolerance. An overview of the main uses of lactose in human
nutrition and in the pharmaceutical industry and the problems derived from this
circumstance are described in this review. Lactose intolerance (LI) is characterized by the presence of primarily
gastrointestinal clinical signs resulting from colonic fermentation of lactose,
the absorption of which is impaired due to a deficiency in the lactase enzyme.
These clinical signs can be modified by several factors, including lactose dose,
residual lactase expression, concurrent ingestion of other dietary components,
gut-transit time, and enteric microbiome composition. In many of individuals
with lactose malabsorption, clinical signs may be absent after consumption of
normal amounts of milk or, in particular, dairy products (yogurt and cheese),
which contain lactose partially digested by live bacteria. The intestinal
microbiota can be modulated by biotic supplementation, which may alleviate the
signs and symptoms of LI. This systematic review summarizes the available
evidence on the influence of prebiotics and probiotics on lactase deficiency and
LI. The literature search was conducted using the MEDLINE (via PUBMED) and
SCOPUS databases following Preferred Reporting Items for Systematic Reviews and
Meta-Analyses (PRISMA) guidelines, and included randomized controlled trials.
For each study selected, the risk of bias was assessed following the Cochrane
Collaboration methodology. Our findings showed varying degrees of efficacy but
an overall positive relationship between probiotics and LI in relation to
specific strains and concentrations. Limitations regarding the wide
heterogeneity between the studies included in this review should be taken into
account. Only one study examined the benefits of prebiotic supplementation and
LI. So further clinical trials are needed in order to gather more evidence. |
What is Etizolam? | Etizolam is a benzodiazepine analogue that is approved for use in Japan, Italy and India as an anxiolytic drug with a pharmacologic profile similar to that of the classic benzodiazepines. Neurochemical research suggests that etizolam may have selectivity for the subpopulation of Y-aminobutyric acid type A receptors associated with anxiety (ie, alpha1, beta2, gamma2). | A double-blind study was carried out in 30 female patients with generalized
anxiety disorders associated with depressive symptoms to compare the
effectiveness and tolerability of etizolam and alprazolam. Patients were
allocated at random to receive one or other drug at a dosage of 0.5 mg twice
daily for 5 weeks. Assessments were made on entry and after 3 and 5 weeks of
treatment using the Hamilton rating scales for anxiety and for depression. The
results showed that both drugs had marked anxiolytic and antidepressive
activity, there being significant reductions after treatment in mean total
rating scores compared to baseline. Although there was no statistically
significant difference between the two drugs, there was a trend for etizolam to
be more effective in relieving anxiety somatization symptoms. Apart from
moderate daytime drowsiness in a few patients, both drugs were considered to be
extremely well tolerated. Etizolam, an anti-anxiety agent which is an antagonist of platelet-activating
factor receptors, was administered to patients with chronic subdural hematoma
(CSH) after hematoma removal to assess the effectiveness for preventing
recurrence compared with control patients not given the drug after surgery. The
remaining volumes of subdural hematomas on brain computed tomography were
measured approximately 1 month after removal. Volume in the etizolam group (15
patients) was significantly smaller than in the control group (24 patients).
Hematoma recurrence was not detected in the etizolam group 3 months after
surgery, but occurred in the control group. The difference was significant.
Etizolam administration may be useful for the prevention of recurrence of CSH. BACKGROUND: Etizolam is an anxiolytic drug with a pharmacologic profile similar
to that of the classic benzodiazepines. Neurochemical research suggests that
etizolam may have selectivity for the subpopulation of Y-aminobutyric acid type
A receptors associated with anxiety (ie, alpha1, beta2, gamma2). This property,
plus its characterization as a ligand with fewer of the adverse events typical
of full agonists (impaired cognitive function, tolerance, and dependence), led
to its selection for this study.
OBJECTIVES: The primary aim of this study was to test for the noninferiority of
etizolam 0.5 mg BID versus placebo in affecting cognitive function in patients
with mild to moderate anxiety disorder of recent onset (<1 month). Anxiety
measures and tolerability were also assessed.
METHODS: Patients between the ages of 18 and 65 years were eligible for
enrollment. This double-blind, placebo-controlled study was performed in 5
centers in Italy using a 2-treatment, 3-period crossover design. Patients were
randomized to 3-week sequences of either etizolam-placebo-placebo or
placebo-etizolam-etizolam. They were evaluated at 4 scheduled visits (screening
and days 7, 14, and 21). Cognitive function was assessed using scores from the
Wechsler Adult Intelligence Scale (WAIS) Digit Span test (total forward and
backward scores and the time required to perform the test). Anxiety was measured
using the Hamilton Anxiety Rating Scale (HAM-A) and the State-Trait Anxiety
Inventory (STAI) for screening and to monitor adequacy of therapy. Blood
pressure, heart rate, weight, and adverse events were also recorded.
RESULTS: A total of 77 white patients were enrolled (mean age, 33.3 years
[range, 22-60 years]; 62.3% female; mean weight, 65.2 kg). With a power of 0.80,
the difference between the effects of etizolam and placebo on WAIS Digit Span
performance was not significant for total score (0.102 [90% CI, -0.130 to
0.335]) or time required for completion (0.029 second [90% CI, -0.574 to
0.632]). Anxiety, as measured using the HAM-A and STAI instruments, did not
differ significantly between groups. No significant differences were found
between etizolam 0.5 mg BID and placebo for cardiovascular events, weight
changes, or adverse events. Mild or moderate somnolence was reported by 7 of 77
patients (9.1% [3 patients while receiving etizolam and 4 patients while
receiving etizolam and placebo]).
CONCLUSIONS: No significant differences between etizolam 0.5 mg BID and placebo
were found for cognitive function or anxiety measures in these patients with
anxiety. Etizolam was well tolerated. The prevalence of benzodiazepine consumption in Japan is one of the highest
worldwide. Etizolam is the most abused drug of the benzodiazepine class. The
treatment of benzodiazepine dependence is difficult. We report a case of
successful dosage reduction in a 24-year-old female patient with etizolam
dependence. She was diagnosed with etizolam dependence at the age of 22 years
old. We proposed a benzodiazepine dependence treatment that involved replacing
etizolam with a long-acting benzodiazepine class drug in conjunction with a
long-term weaning plan. However, the patient refused the treatment and insisted
that reducing the number of tablets would increase her anxiety. After providing
a detailed explanation and receiving consent from the patient, a treatment
regimen consisting of fine granules of etizolam mixed with lactose granules was
begun with the aim of reducing the percentage of etizolam at a rate of 0.3
mg/week. The treatment of etizolam dependence in this patient was successful.
This treatment strategy may be an effective option for patients who are
difficult to treat with conventional methods, or who have anxiety regarding the
reduction of the amount of the drug itself. Tizanidine hydrochloride, α2-receptor stimulant, is a central muscle relaxant.
Etizolam is a benzodiazepine-based anti-anxiety agent. Both drugs are widely
used for the treatment of a variety of muscle pain and frequently used together
in Japan. We experienced a case of complicating prolonged myocardial dysfunction
in a 56-year-old woman. Six hours after overdose of 48 mg tizanidine and 24 mg
etizolam, she showed sinus bradycardia and peripheral vascular resistance
decreasing shock. At that time new ST-T depressions were recognized in
electrocardiography (ECG); however, structural heart diseases were interpreted
as negative by other examinations. Intravenous norepinephrine infusion was
useful to maintain the hemodynamic stability. ECG reversed to normal findings on
day 14; however, the cardiac nuclear medicine studies on day 30 showed severe
fatty metabolic disorder and sympathetic denervation. Non-sustained ventricular
tachycardia was detected. Complete recovery of the myocardium damage required
one year. For one mechanism, it was suggested that over-stimulation of
α2-receptor by tizanidine inhibited the norepinephrine secretion and reuptake at
pre-synaptic surface of adipose cell and cardiac sympathetic nerve. We want to
suggest that the cardiologist should consider the risk of fatal arrhythmia and
long-term myocardium toxicity as the poisoning of the central muscle relaxant
and benzodiazepine agent. <Learning objective: We experienced a case of
complicating prolonged myocardial dysfunction in a 56-year-old woman. Six hours
after overdose of 48 mg tizanidine and 24 mg etizolam, she showed sinus
bradycardia and peripheral vascular resistance decreasing shock. The cardiac
nuclear medicine studies on day 30 showed severe fatty metabolic disorder and
sympathetic denervation. Non-sustained ventricular tachycardia was detected.
Complete recovery of the myocardium damage required one year.>. Etizolam is a drug from the thienotriazoldiazepine class, widely prescribed as
anxiolytic due to its apparently secure toxicological profile. Nevertheless,
some recent cases of etizolam dependence, intoxications and fatalities
associated to its abuse have been reported in the international literature. For
this reason, the drug listed as new psychoactive substance (NPS) by the World
Health Organization (WHO) since 2015. Euphoric effect at high dosage is the
first cause of its recreational use that has determined a wider distribution in
the illicit market. An experimental study was performed to obtain evidence that
etizolam at low therapeutic dosages is a drug with negligible influence on the
psychomotor performances involved in driving. The psychomotor performance was
assessed by performing different tests, such as critical tracking task (CTT),
critical flicker fusion (CFF), choice reaction time (CRT), visual vigilance task
(VVT), response competition test (RCT) in a group of 16 healthy volunteers after
a single administration of etizolam at two different dosages (0.25 mg or
1.00 mg) in comparison to placebo. The test results showed that etizolam at
0.25 mg and 1.00 mg had no significant effect on vigilance, short term memory,
psychomotor coordination or speed in decision making. Differently, abuse of
etizolam to obtain the euphoric effects at presumably high dosages or in
combination with other psychoactive substances could be fatal. The negligible
side effects on mental and behavioral function demonstrated by this study, could
represent an incitement to abuse, which can be strongly discouraged with correct
information on differences between its correct use and its misuse. Etizolam is a novel psychoactive substance and novel benzodiazepine of the
thienotriazolodiazepine class, which has recently seen an increasing trend in
use worldwide. We report a case series of 10 decedents with etizolam and opioids
in their systems. Death investigation, expanded toxicology and medical
investigation information were included for contextualization of etizolam in
death. Etizolam was detected and confirmed within peripheral and cardiac blood,
urine, vitreous humor and, in one case, gastric fluid, by liquid
chromatography-tandem mass spectrometry and liquid chromatography-quadrupole
time of flight mass spectrometry methodologies. Death investigation indicated
nonmedical use of most drugs. Medical investigation commonly noted pulmonary
edema, cardiomegaly and cerebral swelling. The majority of the decedents
appeared to be unaware of the presence of etizolam and succumbed to the mixed
drug toxicity of their routine depressant and narcotic analgesic drug of abuse
in combination with etizolam. Etizolam use continues to be observed and poses as
a potentially lethal contribution to multiple drug toxicity, especially in the
age of the opioid crisis. Assessment of analytes like etizolam requires
up-to-date methodologies and vigilance in testing to better characterize the
toxicology and interpret the contribution to death. Etizolam is a benzodiazepine analogue that is approved for use in Japan, Italy
and India but has recently appeared as a nonapproved product on the illicit drug
market in Europe and North America. Etizolam was identified in a crystalline
material seized at a Kentucky racetrack, raising concerns that this drug may
have been used in racing. The aim of this study was to characterize the
metabolism and excretion of etizolam in horses to generate information on its
disposition and to incorporate the correct urinary and serum target analytes
into anti-doping screening procedures. Etizolam was administered both
intravenous and orally at a dose of 0.1 mg/kg of body weight to three horses
using a two-way crossover design. Pre-administration and post-administration
serum and urine samples were collected and experiments conducted to identify
potential metabolites in these samples. Additionally, in vitro metabolism
studies using horse liver S9 were undertaken to complement the in vivo
metabolism studies. Numerous metabolites were id1entified in both serum and
urine in additional to parent drug, with α-hydroxy-etizolam producing the most
abundant analytical signal (in terms of signal intensity and duration of
detection) of the identified metabolites in both matrices. Therefore,
α-hydroxy-etizolam is considered to be the most appropriate analyte for
detection for anti-doping purposes. Analytical methods were developed and
validated and then applied to post-administration samples to generate
concentrations of etizolam and its major metabolites in serum and urine,
resulting in excretion profiles that can be used to guide approaches to
detecting the use of the drug. Etizolam is a thienodiazepine that although licensed for clinical usage in
Japan, India and South Korea is commonly abused and detected in post-mortem
cases around the world. To date, there are limited data in the literature to
allow for the interpretation of blood concentrations of etizolam in post-mortem
cases. A liquid chromatography with tandem mass spectrometry method was used to
quantitate etizolam concentrations in 28 post-mortem cases where etizolam was
detected. The median concentration of etizolam in femoral blood was 8.5 ng/mL
(range 1.0-172.0 ng/mL; n = 24); in antemortem plasma, the etizolam
concentration range was 4-44 ng/mL (n = 4). The mean age of the individuals
abusing etizolam was 38.5 ± 8.4 years (median 39 years), with the majority being
male (86%). In all of the cases, multiple drugs were detected, with the most
common being pregabalin (61%) followed by morphine/heroin (54%), diazepam (54%)
and benzoylecgonine (21%), illustrating the increasing problem of poly-substance
use in drug abusers. The cause of death in the cases in which etizolam was
detected was multi-drug toxicity in 87.5% of the cases, with 12.5% unrelated to
drug use (hangings and blunt-force trauma). These data will further help
forensic practitioners with the interpretation of post-mortem etizolam
concentrations. Introduction: The use of novel designer drugs has increased worldwide over the
years. Etizolam is a designer benzodiazepine (BZD) that has raised concern
because of its growing non-medical use, liability to tolerance and dependence,
and related harms. Studies exploring the abuse liability and cognitive effects
of etizolam outside the therapeutic doses are lacking. Aims: To explore the
abuse liability of etizolam and the characteristics of patients affected by
etizolam high-dose dependence in a nationwide tertiary referral addiction unit.
To document the cognitive changes to etizolam high-dose use. Design and Methods:
Sociodemographic and clinical data on subjects with etizolam high-dose use were
retrospectively collected from a database of 1,293 patients consecutively
admitted to the Addiction Medicine Unit, Verona University Hospital, Italy for
detoxification from high-dose BZDs or Z-drugs dependence. Thorough
neuropsychological testing explored the cognitive side effects of high-dose
etizolam use. Results: We found eleven etizolam high-dose users, of which eight
used etizolam only, and three used etizolam with other BZDs/zolpidem. All the
patients were prescribed etizolam for medical reasons, i.e., anxiety and/or
insomnia. Neuropsychological evaluation showed deficits of working memory,
visuospatial memory and executive function in a 27-year-old woman who used
etizolam 15 mg daily. Discussion: Our findings suggest that abuse and dependence
liability of etizolam should be considered a public health and social problem.
They offer preliminary evidence on the cognitive side effects of etizolam
high-dose use. Conclusions: This report offers new information on the potential
harms of etizolam in patients who are prescribed this drug for medical reasons. |
Is AZD9668 a VEGF mRNA drug? | AZD9668 is a reversible and selective inhibitor of neutrophil elastase. | BACKGROUND: Neutrophil elastase (NE) is implicated in chronic obstructive
pulmonary disease (COPD). AZD9668 is a reversible and selective inhibitor of NE,
well tolerated at doses of 60 mg bid during Phase I/IIa development.
METHODS: This 12-week, randomised, double-blind, placebo-controlled, Phase IIb,
trial (NCT01023516), investigated the efficacy and safety of AZD9668 (60 mg bid)
versus placebo in patients with symptomatic COPD and a history of exacerbation
receiving maintece budesonide/formoterol. Primary outcome variable: forced
expiratory volume in one second (FEV1). Secondary endpoints included:
post-bronchodilator FEV1, pre- and post-bronchodilator forced vital capacity,
FEV6, forced expiratory flow between 25% and 75% of vital capacity and
inspiratory capacity; peak expiratory flow and FEV1 measured at home;
EXAcerbations of Chronic pulmonary disease Tool and Breathlessness, Cough and
Sputum Scores; St George's respiratory questionnaire for COPD (SGRQ-C) scores;
exacerbations; and safety assessments.
RESULTS: Six hundred and fifteen patients were randomised: placebo (302),
AZD9668 60 mg bid (313). AZD9668 showed no effect on lung function: change in
mean pre-bronchodilator FEV1 versus placebo was 0.01L (95% confidence interval:
-0.03, 0.05; p=0.533). AZD9668 did not significantly improve respiratory signs
and symptoms, SGRQ-C score or time to first exacerbation. Adverse events were
similar for AZD9668 and placebo.
CONCLUSIONS: Three months' treatment with AZD9668 did not improve lung function,
respiratory signs and symptoms or SGRQ-C score when added to
budesonide/formoterol maintece therapy in patients with COPD. In the absence
of definitive biomarkers of short-term disease progression, further research is
needed to determine the optimal duration of studies to evaluate NE inhibitors as
disease-modifying agents. |
What is caused by de novo VPS4A mutations? | De novo VPS4A mutations cause multisystem disease with abnormal neurodevelopment. VPS4A normal function is required for multiple human developmental and cellular processes. | Author information:
(1)Cambridge Institute for Medical Research, University of Cambridge, Cambridge
CB2 0XY, UK; Department of Medical Genetics, University of Cambridge, Cambridge
CB2 0QQ, UK.
(2)Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità,
Rome 00161, Italy.
(3)Department of Haematology, NHS Blood and Transplant Centre, University of
Cambridge, Cambridge CB2 0XY, UK; NIHR BioResource, Cambridge University
Hospitals NHS Foundation Trust, Cambridge Biomedical Campus, Cambridge CB2 0QQ,
UK.
(4)Department of Medical Genetics, University of Cambridge, Cambridge CB2 0QQ,
UK; European Molecular Biology Laboratory - European Bioinformatics Institute
(EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridgeshire CB10 1SA, UK.
(5)Microscopy Area, Core Facilities, Istituto Superiore di Sanità, Rome 00161,
Italy.
(6)Department of Medical Genetics, University of Cambridge, Cambridge CB2 0QQ,
UK.
(7)Cambridge Institute for Medical Research, University of Cambridge, Cambridge
CB2 0XY, UK; Department of Pathology, University of Cambridge, Cambridge CB2
1QP, UK.
(8)Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità,
Rome 00161, Italy; Genetics and Rare Diseases Research Division, Ospedale
Pediatrico Bambino Gesù, IRCCS, Rome 00146, Italy.
(9)Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino
Gesù, IRCCS, Rome 00146, Italy.
(10)Genomics England, London, UK.
(11)Fondazione Policlinico Universitario A. Gemelli-IRCCS, Rome 00168, Italy.
(12)Fondazione Policlinico Universitario A. Gemelli-IRCCS, Rome 00168, Italy;
Università Cattolica del Sacro Cuore, Rome 00168, Italy.
(13)Unit of Mechanisms, Biomarkers and Models, Department of Environment and
Health, Istituto Superiore di Sanità, Rome 00161, Italy.
(14)Department of Clinical Genetics, Great Ormond Street Hospital, London WC1N
3JH, UK.
(15)Department of Paediatric Neurology, Cambridge University Hospitals NHS
Foundation Trust, Cambridge CB2 0QQ, UK.
(16)Department of Clinical Genetics, Liverpool Women's Hospital, Liverpool L8
7SS, UK.
(17)Department of Medical Genetics, Guys' and St Thomas' NHS Foundation Trust,
London SE1 9RT, UK.
(18)Clinical Genetics, Birmingham Women's and Children's NHS Foundation Trust,
Birmingham B15 2TG, UK.
(19)Phoenix Children's Hospital, Phoenix, AZ 76109, USA.
(20)Cook Children's Medical Centre, Fort Worth, TX 76104, USA.
(21)Colchester Hospital, East Suffolk and North Essex NHS Foundation Trust,
Essex CO4 5JL, UK.
(22)Ophthalmology Department, Cambridge University Hospitals NHS Foundation
Trust, Cambridge CB2 0QQ, UK.
(23)Department of Neuroscience and Brain Technologies, Istituto Italiano di
Tecnologia, Genova 16163, Italy; Area of Neuroscience, SISSA, Trieste 34136,
Italy.
(24)Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino
Gesù, IRCCS, Rome 00146, Italy. Electronic address: [email protected].
(25)Cambridge Institute for Medical Research, University of Cambridge, Cambridge
CB2 0XY, UK; Department of Medical Genetics, University of Cambridge, Cambridge
CB2 0QQ, UK. Electronic address: [email protected]. |
What is the use of pegcetacoplan? | Pegcetacoplan is promising for paroxysmal nocturnal haemoglobinuria and Geographic Atrophy. | PURPOSE: Geographic atrophy (GA), a late stage of age-related macular
degeneration (AMD), is a major cause of blindness. Even while central visual
acuity remains relatively well preserved, GA often causes considerable
compromise of visual function and quality of life. No treatment currently
exists. We evaluated the safety and efficacy of pegcetacoplan, a complement C3
inhibitor, for treatment of GA.
DESIGN: Prospective, multicenter, randomized, sham-controlled phase 2 study.
PARTICIPANTS: Two hundred forty-six patients with GA.
METHODS: Patients with GA were assigned randomly in a 2:2:1:1 ratio to receive
intravitreal injections of 15 mg pegcetacoplan monthly or every other month
(EOM) or sham intravitreal injections monthly or EOM for 12 months with
follow-up at months 15 and 18. Area and growth of GA were measured using fundus
autofluorescence imaging.
MAIN OUTCOME MEASURES: The primary efficacy end point was mean change in square
root GA lesion area from baseline to month 12. Secondary outcome measures
included mean change from baseline in GA lesion area without the square root
transformation, distance of GA lesion from the fovea, best-corrected visual
acuity (BCVA), low-lumice BCVA, and low-lumice visual acuity deficit. The
primary safety end point was the number and severity of treatment-emergent
adverse events.
RESULTS: In patients receiving pegcetacoplan monthly or EOM, the GA growth rate
was reduced by 29% (95% confidence interval [CI], 9-49; P = 0.008) and 20% (95%
CI, 0-40; P = 0.067) compared with the sham treatment group. Post hoc analysis
showed that the effect was greater in the second 6 months of treatment, with
observed reductions of 45% (P = 0.0004) and 33% (P = 0.009) for pegcetacoplan
monthly and EOM, respectively. Two cases of culture-positive endophthalmitis and
1 case of culture-negative endophthalmitis occurred in the pegcetacoplan monthly
group. New-onset investigator-determined exudative AMD was reported more
frequently in pegcetacoplan-treated eyes (18/86 eyes [20.9%] and 7/79 eyes
[8.9%] in monthly and EOM groups, respectively) than in sham-treated eyes (1/81
eyes [1.2%]).
CONCLUSIONS: Local C3 inhibition with pegcetacoplan resulted in statistically
significant reductions in the growth of GA compared with sham treatment. Phase 3
studies will define the efficacy and safety profile further. Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired, life-threatening
hematologic disease characterized by chronic complement-mediated hemolysis and
thrombosis. Despite treatment with eculizumab, a C5 inhibitor, 72% of
individuals remain anemic. Pegcetacoplan (APL-2), a PEGylated C3 inhibitor, has
the potential to provide more complete hemolysis control in patients with PNH.
This open-label, phase Ib study was designed to assess the safety, tolerability,
and pharmacokinetics of pegcetacoplan in subjects with PNH who remained anemic
during treatment with eculizumab. Pharmacodynamic endpoints were also assessed
as an exploratory objective of this study. Data are presented for six subjects
in cohort 4 who received treatment for up to 2 years. In total, 427
treatment-emergent adverse events (TEAEs) were reported, 68 of which were
possibly related to the study drug. Eight serious TEAEs occurred in two
subjects; three of these events were considered possibly related to the study
drug. Pegcetacoplan pharmacokinetic concentrations accumulated with repeated
dosing, and steady state was reached at approximately 6-8 weeks. Lactate
dehydrogenase levels were well controlled by eculizumab at baseline.
Pegcetacoplan increased hemoglobin levels and decreased both reticulocyte count
and total bilirubin in all six subjects. Improvements were observed in
Functional Assessment of Chronic Illness Therapy Fatigue scores. Two subjects
discontinued for reasons unrelated to pegcetacoplan. All four subjects who
completed the study transitioned to pegcetacoplan monotherapy following
eculizumab discontinuation and avoided transfusions. In this small study,
pegcetacoplan therapy was generally well-tolerated, and resulted in an improved
hematological response by achieving broad hemolysis control, enabling eculizumab
discontinuation. OBJECTIVES: To evaluate clinical characteristics of eyes in which
investigator-determined new-onset exudative age-related macular degeneration
(eAMD) developed during the FILLY trial.
DESIGN: Post hoc analysis of the phase 2 study of intravitreal pegcetacoplan in
geographic atrophy (GA).
SUBJECTS: Patients with GA secondary to age-related macular degeneration (AMD),
n = 246.
INTERVENTION: Either 15 mg intravitreal pegcetacoplan or sham given monthly or
every other month for 12 months followed by a 6-month off-treatment period.
MAIN OUTCOME MEASURES: Time of new eAMD onset in the study eye, history of eAMD
in the fellow eye, presence of double-layer sign (DLS) on structural OCT in the
study eye, changes in retinal anatomic features by structural OCT and
fluorescein angiography (FA), and changes in visual acuity.
RESULTS: Exudation was reported in 26 study eyes across treatment groups over 18
months. Mean time to eAMD diagnosis was 256 days (range, 31-555 days). Overall,
a higher proportion of patients with a baseline history of eAMD in the fellow
eye (P = 0.016) and a DLS in the study eye (P = 0.0001) demonstrated eAMD. Among
study eyes in which eAMD developed, 18 of 26 (69%) had history of fellow-eye
eAMD and 19 of 26 (73.1%) had DLS at baseline, compared with 76 of 217 study
eyes (35%; P = 0.0007) and 70 of 215 study eyes (32.5%; P < 0.0001),
respectively, in which eAMD did not develop. All 21 patients with structural OCT
imaging at the time of eAMD diagnosis demonstrated subretinal fluid,
intraretinal cysts, or both consistent with exudation. Among 17 patients who
underwent FA at eAMD diagnosis, 10 showed detectable macular neovascularization
(MNV), all occult lesions. Development of eAMD did not have an appreciable
impact on visual acuity, and all patients responded to anti-vascular endothelial
growth factor (VEGF) therapy.
CONCLUSIONS: Intravitreal pegcetacoplan slowed the rate of GA growth and was
associated with an unexpected dose-dependent increased incidence of eAMD with no
temporal clustering of onset. Exudative AMD seemed to be associated with
baseline eAMD in the contralateral eye and a DLS, suggestive of nonexudative
MNV, in the study eye. The safety profile of pegcetacoplan was acceptable to
proceed to phase 3 studies without adjustments to enrollment criteria. BACKGROUND: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired
disease characterized by chronic complement-mediated hemolysis. C5 inhibition
controls intravascular hemolysis in untreated PNH but cannot address
extravascular hemolysis. Pegcetacoplan, a pegylated peptide targeting proximal
complement protein C3, potentially inhibits both intravascular and extravascular
hemolysis.
METHODS: We conducted a phase 3 open-label, controlled trial to assess the
efficacy and safety of pegcetacoplan as compared with eculizumab in adults with
PNH and hemoglobin levels lower than 10.5 g per deciliter despite eculizumab
therapy. After a 4-week run-in phase in which all patients received
pegcetacoplan plus eculizumab, we randomly assigned patients to subcutaneous
pegcetacoplan monotherapy (41 patients) or intravenous eculizumab (39 patients).
The primary end point was the mean change in hemoglobin level from baseline to
week 16. Additional clinical and hematologic markers of hemolysis and safety
were assessed.
RESULTS: Pegcetacoplan was superior to eculizumab with respect to the change in
hemoglobin level from baseline to week 16, with an adjusted (least squares) mean
difference of 3.84 g per deciliter (P<0.001). A total of 35 patients (85%)
receiving pegcetacoplan as compared with 6 patients (15%) receiving eculizumab
no longer required transfusions. Noninferiority of pegcetacoplan to eculizumab
was shown for the change in absolute reticulocyte count but not for the change
in lactate dehydrogenase level. Functional Assessment of Chronic Illness
Therapy-Fatigue scores improved from baseline in the pegcetacoplan group. The
most common adverse events that occurred during treatment in the pegcetacoplan
and eculizumab groups were injection site reactions (37% vs. 3%), diarrhea (22%
vs. 3%), breakthrough hemolysis (10% vs. 23%), headache (7% vs. 23%), and
fatigue (5% vs. 15%). There were no cases of meningitis in either group.
CONCLUSIONS: Pegcetacoplan was superior to eculizumab in improving hemoglobin
and clinical and hematologic outcomes in patients with PNH by providing broad
hemolysis control, including control of intravascular and extravascular
hemolysis. (Funded by Apellis Pharmaceuticals; PEGASUS ClinicalTrials.gov,
NCT03500549.). The FDA approval of pegcetacoplan (Empaveli), a PEGylated compstatin-based C3
therapeutic, as a new treatment for paroxysmal nocturnal hemoglobinuria (PNH)
marks a milestone in the history of complement drug discovery. Almost 15 years
after the approval of the first complement-specific drug for PNH, the anti-C5
antibody eculizumab, a novel class of complement inhibitors with a distinct
mechanism of action finally enters the clinic. This landmark decision broadens
the spectrum of available complement therapeutics, offering patients with unmet
clinical needs or insufficient responses to anti-C5 therapy an alternative
treatment option with a broad activity profile. Here we present a brief
historical account of this newly approved complement drug, consolidating its
approval within the long research record of the compstatin family of peptidic C3
inhibitors. Pegcetacoplan (Empaveli™) is a PEGylated pentadecapeptide developed by Apellis
Pharmaceuticals for the treatment of complement-mediated diseases. It binds to
complement component 3 (C3) and its activation fragment C3b, controlling the
cleavage of C3 and the generation of the downstream effectors of complement
activation and thus both C3b-mediated extravascular haemolysis and terminal
complement-mediated intravascular haemolysis. Pegcetacoplan is the first
C3-targeted paroxysmal nocturnal haemoglobinuria (PNH) therapy to be approved
(in May 2021) in the USA, where it is indicated for the treatment of adults with
PNH, including those switching from C5 inhibitor therapy with eculizumab and
ravulizumab. A regulatory assessment of pegcetacoplan for the treatment of PNH
is currently underway in the EU and Australia. Pegcetacoplan is also being
investigated as a therapeutic option in other complement-mediated diseases,
including age-related macular degeneration, C3 glomerulopathy and autoimmune
haemolytic anaemia. The recommended dosage regimen of pegcetacoplan is 1080 mg
twice weekly, administered as a subcutaneous infusion via an infusion pump with
a ≥ 20 mL reservoir. This article summarizes the milestones in the development
of pegcetacoplan leading to this first approval for the treatment of adults with
PNH. Complement is an elaborate system of innate immunity. Genetic variants and
autoantibodies leading to excessive complement activation are implicated in a
variety of human diseases. Among them, the hematologic disease paroxysmal
nocturnal hemoglobinuria (PNH) remains the prototypic model of complement
activation and inhibition. Eculizumab, the first-in-class complement inhibitor,
was approved for PNH in 2007. Addressing some of the unmet needs, a long-acting
C5 inhibitor, ravulizumab, and a C3 inhibitor, pegcetacoplan, have also now been
approved for PNH. Novel agents, such as factor B and factor D inhibitors, are
under study, with very promising results. In this era of several approved
targeted complement therapeutics, selection of the proper drug must be based on
a personalized approach. Beyond PNH, complement inhibition has also shown
efficacy and safety in cold agglutinin disease, primarily with the C1s inhibitor
of the classical complement pathway sutimlimab, as well as with pegcetacoplan.
Furthermore, C5 inhibition with eculizumab and ravulizumab, as well as
inhibition of the lectin pathway with narsoplimab, is being investigated in
transplantation-associated thrombotic microangiopathy. With this revolution of
next-generation complement therapeutics, additional hematologic entities, such
as delayed hemolytic transfusion reaction or immune thrombocytopenia, might also
benefit from complement inhibitors. Therefore, this review aims to describe
state-of-the-art knowledge of targeting complement in hematologic diseases,
focusing on (1) complement biology for the clinician, (2) complement activation
and therapeutic inhibition in prototypic complement-mediated hematologic
diseases, (3) hematologic entities under investigation for complement
inhibition, and (4) other complement-related disorders of potential interest to
hematologists. |
What is the activity of a Oligosaccharyltransferases ? | oligosaccharyltransferases (OSTs), which catalyze the attachment of glycans to specific amino acid residues in target proteins | Protein glycosylation, or the attachment of sugar moieties (glycans) to
proteins, is important for protein stability, activity, and immunogenicity.
However, understanding the roles and regulations of site-specific glycosylation
events remains a significant challenge due to several technological limitations.
These limitations include a lack of available tools for biochemical
characterization of enzymes involved in glycosylation. A particular challenge is
the synthesis of oligosaccharyltransferases (OSTs), which catalyze the
attachment of glycans to specific amino acid residues in target proteins. The
difficulty arises from the fact that canonical OSTs are large (>70 kDa) and
possess multiple transmembrane helices, making them difficult to overexpress in
living cells. Here, we address this challenge by establishing a bacterial
cell-free protein synthesis platform that enables rapid production of a variety
of OSTs in their active conformations. Specifically, by using lipid odiscs as
cellular membrane mimics, we obtained yields of up to 420 μg/ml for the
single-subunit OST enzyme, "Protein glycosylation B" (PglB) from Campylobacter
jejuni, as well as for three additional PglB homologs from Campylobacter coli,
Campylobacter lari, and Desulfovibrio gigas. Importantly, all of these enzymes
catalyzed N-glycosylation reactions in vitro with no purification or processing
needed. Furthermore, we demonstrate the ability of cell-free synthesized OSTs to
glycosylate multiple target proteins with varying N-glycosylation acceptor
sequons. We anticipate that this broadly applicable production method will
advance glycoengineering efforts by enabling preparative expression of
membrane-embedded OSTs from all kingdoms of life. Oligosaccharyltransferases (OSTs) mediate the en bloc transfer of N-glycan
intermediates onto the asparagine residue in glycosylation sequons (N-X-S/T,
X≠P). These enzymes are typically heteromeric complexes composed of several
membrane-associated subunits, in which STT3 is highly conserved as a catalytic
core. Metazoan organisms encode two STT3 genes (STT3A and STT3B) in their
genome, resulting in the formation of at least two distinct OST isoforms
consisting of shared subunits and complex specific subunits. The STT3A isoform
of OST primarily glycosylates substrate polypeptides cotranslationally, whereas
the STT3B isoform is involved in cotranslational and post-translocational
glycosylation of sequons that are skipped by the STT3A isoform. Here, we
describe mutant constructs of monomeric enhanced green fluorescent protein
(mEGFP), which are susceptible to STT3B-dependent N-glycosylation. The
endoplasmic reticulum-localized mEGFP (ER-mEGFP) mutants contained an
N-glycosylation sequon at their C-terminus and exhibited increased fluorescence
in response to N-glycosylation. Isoform-specific glycosylation of the constructs
was confirmed by using STT3A- or STT3B-knockout cell lines. Among the mutant
constructs that we tested, the ER-mEGFP mutant containing the N185 -C186 -T187
sequon was the best substrate for the STT3B isoform in terms of glycosylation
efficiency and fluorescence change. Our results suggest that the mutant ER-mEGFP
is useful for monitoring STT3B-dependent post-translocational N-glycosylation in
cells of interest, such as those from putative patients with a congenital
disorder of glycosylation. Lipid-linked oligosaccharides (LLOs) play an important role in the
N-glycosylation pathway as the donor substrate of oligosaccharyltransferases
(OSTs), which are responsible for the en bloc transfer of glycan chains onto a
nascent polypeptide. The lipid component of LLO in both eukarya and archaea
consists of a dolichol, and an undecaprenol in prokarya, whereas the number of
isoprene units may change between species. Given the potential relevance of LLOs
and their related enzymes to diverse biotechnological applications, obtaining
reliable LLO models from distinct domains of life could support further studies
on complex formation and their processing by OSTs, as well as protein
engineering on such systems. In this work, molecular modeling techniques, such
as quantum mechanics calculations, molecular dynamics simulations, and
metadynamics were employed to study eukaryotic (Glc3-Man9-GlcNAc2-PP-Dolichol),
bacterial (Glc1-GalNAc5-Bac1-PP-Undecaprenol), and archaeal
(Glc1-Man1-Gal1-Man1-Glc1-Gal1-Glc1-P-Dolichol) LLOs in membrane bilayers.
Microsecond molecular dynamics simulations and metadynamics calculations of LLOs
revealed that glycan chains are more prone to interact with the membrane lipid
head groups, while the PP linkages are positioned at the lipid phosphate head
groups level. The dynamics of isoprenoid chains embedded within the bilayer are
described, and membrane dynamics and related properties are also investigated.
Overall, there are similarities regarding the structure and dynamics of the
eukaryotic, the bacterial, and the archaeal LLOs in bilayers, which can support
the comprehension of their association with OSTs. These data may support future
studies on the transferring mechanism of the oligosaccharide chain to an
acceptor protein. Bioconjugate vaccines, consisting of polysaccharides attached to carrier
proteins, are enzymatically generated using prokaryotic glycosylation systems in
a process termed bioconjugation. Key to bioconjugation are a group of enzymes
known as oligosaccharyltransferases (OTases) that transfer polysaccharides to
engineered carrier proteins containing conserved amino acid sequences known as
sequons. The most recently discovered OTase, PglS, has been shown to have the
broadest substrate scope, transferring many different types of bacterial glycans
including those with glucose at the reducing end. However, PglS is currently the
least understood in terms of the sequon it recognizes. PglS is a pilin-specific
O-linking OTase that naturally glycosylates a single protein, ComP. In addition
to ComP, we previously demonstrated that an engineered carrier protein
containing a large fragment of ComP is also glycosylated by PglS. Here we sought
to identify the minimal ComP sequon sufficient for PglS glycosylation. We tested
>100 different ComP fragments individually fused to Pseudomonas aeruginosa
exotoxin A (EPA), leading to the identification of an 11-amino acid sequence
sufficient for robust glycosylation by PglS. We also demonstrate that the
placement of the ComP sequon on the carrier protein is critical for stability
and subsequent glycosylation. Moreover, we identify novel sites on the surface
of EPA that are amenable to ComP sequon insertion and find that Cross-Reactive
Material 197 fused to a ComP fragment is also glycosylated. These results
represent a significant expansion of the glycoengineering toolbox as well as our
understanding of bacterial O-linking sequons. Glycosylation is increasingly recognised as a common protein modification within
bacterial proteomes. While great strides have been made in identifying species
that contain glycosylation systems, our understanding of the proteins and sites
targeted by these systems is far more limited. Within this work we explore the
conservation of glycoproteins and glycosylation sites across the
pan-Burkholderia glycoproteome. Using a multi-protease glycoproteomic approach,
we generate high-confidence glycoproteomes in two widely utilized B. cenocepacia
strains, K56-2 and H111. This resource reveals glycosylation occurs exclusively
at Serine residues and that glycoproteins/glycosylation sites are highly
conserved across B. cenocepacia isolates. This preference for glycosylation at
Serine residues is observed across at least 9 Burkholderia glycoproteomes,
supporting that Serine is the domit residue targeted by PglL-mediated
glycosylation across the Burkholderia genus. Combined, this work demonstrates
that PglL enzymes of the Burkholderia genus are Serine-preferring
oligosaccharyltransferases that target conserved and shared protein substrates. |
On what chromosome would the MKKS gene for McKusick-Kaufman(AKA Kaufman-McKusick) syndrome be found? | The MKKS gene is mapped to chromosome 20 | McKusick-Kaufman syndrome (MKKS, MIM 236700) is a human developmental anomaly
syndrome comprising hydrometrocolpos (HMC), postaxial polydactyly (PAP) and
congenital heart disease (CHD). MKKS has been mapped in the Old Order Amish
population to 20p12, between D20S162 and D20S894 (ref. 3). Here we describe the
identification of a gene mutated in MKKS. We analysed the approximately 450-kb
candidate region by sample sequencing, which revealed the presence of several
known genes and EST clusters. We evaluated candidate transcripts by
northern-blot analysis of adult and fetal tissues. We selected one transcript
with widespread expression, MKKS, for analysis in a patient from the Amish
pedigree and a sporadic, non-Amish case. The Old Order Amish patient was found
to be homozygous for an allele that had two missense substitutions and the
non-Amish patient was a compound heterozygote for a frameshift mutation
predicting premature protein truncation and a distinct missense mutation. The
MKKS predicted protein shows amino acid similarity to the chaperonin family of
proteins, suggesting a role for protein processing in limb, cardiac and
reproductive system development. We believe that this is the first description
of a human disorder caused by mutations affecting a putative chaperonin
molecule. We report a 19-year-old, non-Amish Caucasian female patient with primary
amenorrhea caused by complete lack of Müllerian fusion with vaginal agenesis or
Müllerian aplasia (MA), postaxial polydactyly (PAP), and tetralogy of Fallot.
The genital tract anomaly of MA with and without renal or skeletal anomalies
comprises Mayer-Rokitansky-Kuster-Hauser syndrome, which has not been reported
with tetralogy of Fallot. The phenotypic triad of anomalies most closely
resembled McKusick-Kaufman syndrome (MKS; OMIM 236700), a rare multiple
congenital anomaly syndrome comprised of hydrometrocolpos (HMC), PAP, and
congenital heart malformation that is inherited in an autosomal recessive
pattern. While upper reproductive tract anomalies have not been reported with
MKS, they have been reported with Bardet-Biedl syndrome (BBS), a syndrome that
significantly overlaps with MKS. Both MKS and BBS can be caused by mutations in
the MKKS or BBS6 gene on chromosome 20p12 and BBS is also associated with
mutations in other genes (BBS1, BBS2, BBS4, and BBS7). To address this
heterogenity, we sequenced the causative genes in MKS and BBS but no mutations
in these five genes were identified. Fluorescence in situ hybridization (FISH)
excluded large deletions of chromosome 20p12 and microsatellite marker studies
confirmed biparental inheritance for all of the known BBS loci. The dual midline
fusion defects of tetralogy of Fallot and MA suggests that either this patient
has a unique syndrome with a distinct genetic etiology or that she has a
genetically heterogeneous or variant form of MKS. McKusick-Kaufman syndrome (MKS, OMIM #236700) is a rare syndrome inherited in an
autosomal recessive pattern with a phenotypic triad comprising hydrometrocolpos
(HMC), postaxial polydactyly (PAP), and congenital cardiac disease (CHD). The
syndrome is caused by mutations in the MKKS gene mapped onto chromosome 20p12
between D20S162 and D20S894 markers. Mutations in the same gene causes
Bardet-Biedl-6 syndrome (BBS-6, OMIM #209900) inherited in an autosomal
recessive pattern. BBS-6 comprises retinitis pigmentosa, polydactyly, obesity,
mental retardation, renal and genital anomalies. HMC, CHD, and PAP defects can
also occur in BBS-6, and there is a significant clinical overlap between MKS and
BBS-6 in childhood. We describe a new borderline case of MKS and BBS syndrome
and suggest insights for understanding correlation between MKKS gene mutations
and clinical phenotype. Here, we report the results of molecular analysis of
MKKS in a female proband born in an Italian nonconsanguineous healthy family
that presents HMC and PAP. The mutational screening revealed the presence of two
different heterozygous missense variants (p.242A>S in exon 3, p.339 I>V in exon
4) in the MKKS gene, and a nucleotide variation in 5'UTR region in exon 2 (-417
A>C). |
Which maternal CYP2D6 related phenotype may expose their infants to risk of adverse events when taking codeine while breastfeeding? | Mothers with a CYP2D6 ultrarapid metabolizer phenotype may expose their infants to risk of adverse events when taking codeine while breastfeeding, by producing more of the active metabolite, morphine. | |
Describe the web application VICTOR | VICTOR is a free, dependency-free visual analytics web application that allows the visual comparison of the results of various clustering algorithms. It can handle multiple cluster set results simultaneously and compare them using ten different metrics. Clustering results can be filtered and compared with the use of data tables or interactive heatmaps, bar plots, correlation networks, sankey and circos plots. | Clustering is the process of grouping different data objects based on similar
properties. Clustering has applications in various case studies from several
fields such as graph theory, image analysis, pattern recognition, statistics and
others. Nowadays, there are numerous algorithms and tools able to generate
clustering results. However, different algorithms or parameterizations may
produce quite dissimilar cluster sets. In this way, the user is often forced to
manually filter and compare these results in order to decide which of them
generate the ideal clusters. To automate this process, in this study, we present
VICTOR, the first fully interactive and dependency-free visual analytics web
application which allows the visual comparison of the results of various
clustering algorithms. VICTOR can handle multiple cluster set results
simultaneously and compare them using ten different metrics. Clustering results
can be filtered and compared to each other with the use of data tables or
interactive heatmaps, bar plots, correlation networks, sankey and circos plots.
We demonstrate VICTOR's functionality using three examples. In the first case,
we compare five different network clustering algorithms on a Yeast
protein-protein interaction dataset whereas in the second example, we test four
different parameters of the MCL clustering algorithm on the same dataset.
Finally, as a third example, we compare four different meta-analyses with
hierarchically clustered differentially expressed genes found to be involved in
myocardial infarction. VICTOR is available at http://victor.pavlopouloslab.info
or http://bib.fleming.gr:3838/VICTOR. |
What is GLS-5700? | GLS-5700 is a synthetic, consensus DNA vaccine encoding the ZIKV premembrane and envelope proteins that was tested for Zika virus disease. | 1. BACKGROUND: Zika virus (ZIKV) infection has been associated with prolonged viral
excretion in human semen and causes testicular atrophy and infertility in
10-week-old immunodeficient mice.
METHODS: Male IFNAR-/- mice, knockout for type I interferon receptor, were
immunized with GLS-5700, a deoxyribonucleic acid-based vaccine, before a
subcutaneous ZIKV challenge with 6 × 105 plaque-forming units at 13 weeks of
age. On day 28 postinfection, testes and epididymides were collected in some
mice for histological and functional analyses, whereas others were mated with
naive female wild-type C57BL/6J.
RESULTS: Although all mice challenged with ZIKV developed viremia, most of them
were asymptomatic, showed no weight loss, and survived infection. On day 28
postinfection, none of the unvaccinated, infected mice (9 of 9) exhibited
abnormal spermatozoa counts or motility. However, 33% (3 of 9) and 36% (4 of 11)
of mated males from this group were infertile, from 2 independent studies.
Contrarily, males from the noninfected and the vaccinated, infected groups were
all fertile. On days 75 and 207 postinfection, partial recovery of fertility was
observed in 66% (2 of 3) of the previously infertile males.
CONCLUSIONS: This study reports the effects of ZIKV infection on male fertility
in a sublethal, immunodeficient mouse model and the efficacy of GLS-5700
vaccination in preventing male infertility. BACKGROUND: Although Zika virus (ZIKV) infection is typically self-limiting,
other associated complications such as congenital birth defects and the
Guillain-Barré syndrome are well described. There are no approved vaccines
against ZIKV infection.
METHODS: In this phase 1, open-label clinical trial, we evaluated the safety and
immunogenicity of a synthetic, consensus DNA vaccine (GLS-5700) encoding the
ZIKV premembrane and envelope proteins in two groups of 20 participants each.
The participants received either 1 mg or 2 mg of vaccine intradermally, with
each injection followed by electroporation (the use of a pulsed electric field
to introduce the DNA sequence into cells) at baseline, 4 weeks, and 12 weeks.
RESULTS: The median age of the participants was 38 years, and 60% were women;
78% were White and 22% Black; in addition, 30% were Hispanic. At the interim
analysis at 14 weeks (i.e., after the third dose of vaccine), no serious adverse
events were reported. Local reactions at the vaccination site (e.g.,
injection-site pain, redness, swelling, and itching) occurred in approximately
50% of the participants. After the third dose of vaccine, binding antibodies (as
measured on enzyme-linked immunosorbent assay) were detected in all the
participants, with geometric mean titers of 1642 and 2871 in recipients of 1 mg
and 2 mg of vaccine, respectively. Neutralizing antibodies developed in 62% of
the samples on Vero-cell assay. On neuronal-cell assay, there was 90% inhibition
of ZIKV infection in 70% of the serum samples and 50% inhibition in 95% of the
samples. The intraperitoneal injection of postvaccination serum protected 103 of
112 IFNAR knockout mice (bred with deletion of genes encoding interferon-α and
interferon-β receptors) (92%) that were challenged with a lethal dose of
ZIKV-PR209 strain; none of the mice receiving baseline serum survived the
challenge. Survival was independent of the neutralization titer.
CONCLUSIONS: In this phase 1, open-label clinical trial, a DNA vaccine elicited
anti-ZIKV immune responses. Further studies are needed to better evaluate the
safety and efficacy of the vaccine. (Funded by GeneOne Life Science and others;
ZIKA-001 ClinicalTrials.gov number, NCT02809443.). |
Is histone variant H3.3K27M associated with gliomas? | Yes,
Diffuse intrinsic pontine gliomas (DIPG) are the most aggressive brain tumors in children with 5-year survival rates of only 2%. About 85% of all DIPG are characterized by a lysine-to-methionine substitution in histone 3, which leads to global H3K27 hypomethylation accompanied by H3K27 hyperacetylation. | Histone H3.3 mutations are a hallmark of pediatric gliomas, but their core
oncogenic mechanisms are not well-defined. To identify major effectors, we used
CRISPR-Cas9 to introduce H3.3K27M and G34R mutations into previously
H3.3-wildtype brain cells, while in parallel reverting the mutations in glioma
cells back to wildtype. ChIP-seq analysis broadly linked K27M to altered
H3K27me3 activity including within super-enhancers, which exhibited perturbed
transcriptional function. This was largely independent of H3.3 DNA binding. The
K27M and G34R mutations induced several of the same pathways suggesting key
shared oncogenic mechanisms including activation of neurogenesis and NOTCH
pathway genes. H3.3 mutant gliomas are also particularly sensitive to NOTCH
pathway gene knockdown and drug inhibition, reducing their viability in culture.
Reciprocal editing of cells generally produced reciprocal effects on
tumorgenicity in xenograft assays. Overall, our findings define common and
distinct K27M and G34R oncogenic mechanisms, including potentially targetable
pathways. Diffuse intrinsic pontine gliomas (DIPG) are the most aggressive brain tumors in
children with 5-year survival rates of only 2%. About 85% of all DIPG are
characterized by a lysine-to-methionine substitution in histone 3, which leads
to global H3K27 hypomethylation accompanied by H3K27 hyperacetylation.
Hyperacetylation in DIPG favors the action of the Bromodomain and Extra-Terminal
(BET) protein BRD4, and leads to the reprogramming of the enhancer landscape
contributing to the activation of DIPG super enhancer-driven oncogenes. The
activity of the acetyltransferase CREB-binding protein (CBP) is enhanced by BRD4
and associated with acetylation of nucleosomes at super enhancers (SE). In
addition, CBP contributes to transcriptional activation through its function as
a scaffold and protein bridge. Monotherapy with either a CBP (ICG-001) or BET
inhibitor (JQ1) led to the reduction of tumor-related characteristics.
Interestingly, combined treatment induced strong cytotoxic effects in
H3.3K27M-mutated DIPG cell lines. RNA sequencing and chromatin
immunoprecipitation revealed that these effects were caused by the inactivation
of DIPG SE-controlled tumor-related genes. However, single treatment with
ICG-001 or JQ1, respectively, led to activation of a subgroup of detrimental
super enhancers. Combinatorial treatment reversed the inadvertent activation of
these super enhancers and rescued the effect of ICG-001 and JQ1 single treatment
on enhancer-driven oncogenes in H3K27M-mutated DIPG, but not in H3 wild-type
pedHGG cells. In conclusion, combinatorial treatment with CBP and BET inhibitors
is highly efficient in H3K27M-mutant DIPG due to reversal of inadvertent
activation of detrimental SE programs in comparison with monotherapy. |
What is another name for keratomileusis? | Report the outcomes of laser in situ keratomileusis (LASIK) for high myopia correction after long-term follow-up | BACKGROUND: LASIK (Laser in situ keratomileusis) is used in refractive surgery
especially for correction of higher degrees of myopia. Preservation of Bowman's
layer as well as less postoperative pain and the slight to absent subepithelial
haze are regarded as advantages compared to photorefractive keratectomy (PRK).
However, numerous serious complications have been described in the literature.
PATIENTS AND METHODS: LASIK treatment was performed elsewhere in two patients to
treat myopia or myopic astigmatism between -6 and -9 diopters (D). An
astigmatism of -6 D was corrected with the LASIK method in another patient with
keratoconus. Progressive corneal ectasia of up to seven diopters occurred in all
four eyes within a few months.
CONCLUSION: Corneal ectasia can occur after LASIK even in low degrees of myopia
of less than ten diopters. Recently, -12 D has been specified as the upper limit
for this technique. It is especially important to rule out an early keratoconus
or a forme fruste of keratoconus preoperatively since keratectasia with
particularly rapid progression can occur in such cases: we would like to
designate this as "maligt keratoconus". PURPOSE: Ectasia after laser in situ keratomileusis (LASIK) is a rare but
serious complication. Prevention includes proper patient selection with
detection of those at particular risk. Causes of ectasia include predisposition,
excessive ablation with less than 250 microm of residual stromal bed, thicker
than normal flap, irregular corneal thickness, and different ablation rates.
METHODS: We evaluated corneal curvature patterns and their relationship to
corneal topography and pachymetry maps.
RESULTS: Corneal topography (axial, tangential, and altimetric) and pachymetry
map characteristics of normally astigmatic corneas, keratoconus, false-positive
and false-negative cases, as well as contact lens-induced warpage are discussed.
CONCLUSIONS: Preoperative pachymetry maps for LASIK surgery allow accurate case
selection through detection of borderline cases, and provide important
documentation of preoperative status, as well as useful information for
improving surgical strategy. Another important parameter is the asphericity
index. BACKGROUND: Laser epithelial keratomileusis (LASEK) is a new keratorefractive
procedure for the correction of myopia and myopic astigmatism, which may combine
advantages and eliminate disadvantages of photorefractive keratectomy (e.g.
pain, corneal haze) and laser in situ keratomileusis (e.g. flap and interface
complications, dry eye, keratectasia). We present the results of 108
consecutively LASEK-treated eyes with a follow-up period of 12 months.
PATIENTS AND METHODS: LASEK was performed on 108 consecutive eyes with myopia or
myopic astigmatism using a keracor 117 excimer laser. The mean preoperative
refraction was -4.12+/-1.30 diopters (D) spherical equivalent range: -1.75 to
-6.0 D and maximal cylinder was 3.25 D. Results of the 12 months visit are
available for 101 eyes (93.5%).
RESULTS: No serious complications were observed. After 12 months, SE was within
+/-1.0 D of emmetropia in 96% and within +/-0.5 D in 86% of the eyes; 6 eyes had
to be retreated. None of the eyes showed haze worse than grade 1 or lost more
than one line of best-corrected visual acuity. Uncorrected visual acuity (UCVA)
was > or =20/20 in 80% and > or =20/40 in 98%.
CONCLUSIONS: Laser epithelial keratomileusis (LASEK) seems to be safe and
effective in treatment of myopia and myopic astigmatism of up to -6.0 D.
Preliminary results compare favourably with those after photorefractive
keratectomy and laser in situ keratomileusis. Haze formation after LASEK seems
to be low. Coverage of the stromal wound with a vital epithelial flap could
positively influence postoperative wound healing reactions. Photorefractive keratectomy, laser epithelial keratomileusis (LASEK) and
Epi-LASIK are all variants of a similar type refractive surgery involving laser
on the surface of the cornea and differ mainly in management of the epithelium.
Although laser in situ keratomileusis (LASIK) is currently the most popular form
of refractive surgery, LASEK is the procedure of choice in some patients. We
highlight potential complications of LASEK and how these may be managed.
Following laser refractive surgery, corneal thickness is reduced, which has
implications for intraocular pressure measurement and glaucoma screening and
management. This is particularly important following surface laser procedures
where no evidence of previous surgery may be visible. In the event that cataract
surgery is required at a later date, correct calculation of the appropriate
intraocular lens power can be difficult and it thus important that patients are
given their preoperative keratometry readings and refraction. Compared with
LASIK patients, those who undergo LASEK are considered to be at lower risk of
corneal ectasia. Improved understanding of wound healing post LASEK and better
postoperative pain management are ongoing challenges. Keratomileusis, brainchild of Jose I. Barraquer Moner, was conceived and
developed as the first stromal sculpting method to correct refractive error in
1948. The word "keratomileusis" literally means "sculpting" of the "cornea."
Barraquer's first procedures involved freezing a disc of anterior corneal tissue
before removing stromal tissue with a lathe. Over the years, the procedure
continued to develop, first through the Barraquer-Krumeich-Swinger non-freeze
technique where tissue was removed from the underside of the disc by a second
pass of the microkeratome. In-situ keratomileusis was later developed by passing
the microkeratome a second time directly on the stromal bed. The procedure
became known as automated lamellar keratoplasty with the invention of an
automated microkeratome and was further refined by replacing the disc without
sutures and later by stopping the microkeratome before the end of the pass to
create a hinged flap, as first demonstrated in 1989. The history of the excimer
laser dates back to 1900 and the quantum theory, eventually leading to the
discovery that 193-nm ultraviolet excimer laser pulses could photoablate tissue
without thermal damage. Ultrastructural and wound healing studies confirmed that
large area ablation could be performed in the central cornea. This was described
as photorefractive keratectomy in 1986 and the first sighted eyes were treated
in 1988. An excimer laser was first used to sculpt from the stromal bed under a
hinged flap created manually using a trephine and scalpel in 1988. The
incorporation of a microkeratome in 1990 finally led to laser in situ
keratomileusis-LASIK-as we know it today. A 33-year-old man who underwent uneventful laser in situ keratomileusis (LASIK)
developed pressure-induced stromal edema resulting in an interface haze in both
eyes and a pocket of fluid under the flap of the right eye 10 days after
surgery, while receiving topical fluorometholone. Intraocular pressure by
applanation tonometry was 16 mm Hg in his right eye (erroneous result due to the
fluid in the interface) and 34 mm Hg in his left eye. After discontinuation of
steroids and addition of ocular hypotensive medication, interface fluid
collection disappeared in his right eye. Visual acuity improved and haze
diminished in both eyes. This case illustrates that in the same patient a
post-LASIK edema induced syndrome may be present with or without fluid in the
interface, suggesting that both clinical pictures could be manifestations of a
broad spectrum of the same condition. We suggest a new name for this
non-inflammatory disorder: post-LASIK edema-induced keratopathy (PLEK). Refractive surgery includes all procedures which are primarily targeted at
changing the refractive power of the eye. Currently laser-assisted in situ
keratomileusis (LASIK) is indicated to correct myopia of up to - 8 D, hyperopia
up to + 3 D and astigmatism up to 5 D. Photorefractive keratectomy (PRK) and
laser epithelial keratomileusis (LASEK) are primarily recommended for myopia up
to - 6 D and for greater refractive errors, phakic intraocular lenses (IOL) are
the first choice (myopia greater than - 6 D and hyperopia greater than + 3 D).
If presbyopia is present in addition to the high refractive error, refractive
lens exchange is another alternative. OBJECTIVE: Report the outcomes of laser in situ keratomileusis (LASIK) for high
myopia correction after long-term follow-up.
METHODS: Retrospective, consecutive, clinical study including 70 eyes that
underwent LASIK using a 500 Hertz (Hz) repetition rate excimer laser and
femtosecond technology for flap creation. Visual, refractive, corneal
aberrations, and correlation among the variables were evaluated during 3 years.
In addition, 34 eyes were followed during 5 years.
RESULTS: Significant improvement of 17 logMAR lines was observed in uncorrected
vision at 5 years (p < 0.01). This was consistent with spherical equivalent
reduction that came from mean preoperative -7.79 diopters (D) to 5 years
postoperative -0.24 D (p < 0.01). Significant induction of primary spherical
aberration and coma aberration was also found (p < 0.01) at 3 months with levels
of 0.61 µm and 0.47 µm, respectively, with no further changes at 5 years (p >
0.05). Pearson correlation showed that the amount of high-order aberrations at
3 months postoperativeley was significantly correlated with the changes in the
keratometry throughout the 5 years (delta K) (R2 0.242 p = 0.05). Finally,
preoperative corneal asphericity showed an inverse correlation with the delta K
(R2 -308 p = 0.01).
CONCLUSIONS: Results from this study suggests that LASIK for high myopia
correction using 500 Hz repetition rate excimer laser provides stable visual,
refractive and aberrometric results after 5 years of follow-up. A more prolate
cornea and the amount of higher-order aberrations induced after LASIK are
factors that negatively impact in the long-term stability of the procedure. PURPOSE: Laser in situ keratomileusis (LASIK) and small-incision lenticule
extraction (SMILE) are popular refractive surgeries. The objective refractive
outcomes of LASIK and SMILE have been studied extensively; both procedures have
comparable safety, efficacy, and predictability. However, owing to various
psychosocial factors, refractive patients may report dissatisfaction despite
good postoperative vision. Hence the importance of studies on subjective
patient-reported outcomes. This review discusses the role of
psychometric-technique-based validated questionnaires when evaluating subjective
outcomes. It also summarizes the literature on patient-reported outcomes for
LASIK and SMILE.
DESIGN: A literature search was performed on PubMed database to identify studies
that have assessed patient-reported outcomes for LASIK and SMILE.
RESULTS: Several studies have looked into patient-reported outcome measures for
LASIK, but the number of equivalent studies for SMILE is limited. Questionnaires
(validated and non-validated) are used to evaluate patient-reported outcomes.
Validated questionnaires are designed based on psychometric techniques, such as
Classic Test Theory, Item Response Theory, and Rasch analysis. The Quality of
Life Impact of Refractive Correction (QIRC) questionnaire, a validated
questionnaire administered to both LASIK and SMILE patients, suggests that both
groups have comparable vision-related quality of life in the first few months
postoperatively; but SMILE might confer a slight advantage in the later
postoperative period (postoperative month 6).
CONCLUSIONS: Future LASIK-SMILE comparative studies utilizing standardized
validated questionnaires for patient-reported outcome measures with longer
follow-up durations would be a welcome contribution to this important aspect of
refractive surgery. PURPOSE: To provide an overview of the currently available retreatment methods
after myopic small-incision lenticule extraction (SMILE).
DESIGN: Systematic literature review.
METHODS: The PubMed library was searched for articles containing the terms
"small-incision lenticule extraction" and "enhancement" or "retreatment". The
last search was performed on May 1, 2019.
RESULTS: In contrast to laser in-situ keratomileusis (LASIK), which can be
retreated by a flap relift, repeat SMILE retreatment is currently not approved
and only seldomly performed. As substitutes, surface ablation, cap-to-flap
conversion using the CIRCLE program in the VisuMax platform, and thin-flap LASIK
have been recently established. While all options offer safety and efficacy
comparable to LASIK retreatments, each has its patient-specific advantages and
disadvantages. While surface ablation preserves the flap-free approach of the
primary procedure, the aspect of pain and a slow visual recovery might render it
less attractive as compared with CIRCLE and thin-flap LASIK which offer quick
recovery, however at the price of flap creation. Besides, each retreatment
method generates specific tissue responses and has a different impact on corneal
biomechanics, which is strongly dependent on the previous SMILE parameters,
especially the cap thickness.
CONCLUSIONS: Refractive enhancement after SMILE is currently mostly performed by
surface ablation, CIRCLE cap-to-flap conversion or thin-flap LASIK, which all
offer safety and efficacy comparable to LASIK retreatments. In this review, a
detailed overview over each method, its technical aspects, and specific
advantages and disadvantages is given. |
In which motif of the RUNX1T1 protein is the rs34269950 SNP located? | The rs34269950 SNP of RUNX1T1 is located in the 'RRACH' motif. | BACKGROUND: Runt-related transcription factor 1 (RUNX1T1) isoforms are involved
in adipogenesis. RUNX1T1 is mediated by the fat mass and obesity-associated
(FTO). However, the extent to which RUNX1T1 single-nucleotide polymorphisms
(SNPs) are associated with obesity risk or metabolic abnormalities in a
community population basis is unknown.
METHODS: Samples were obtained from the Australian Crossroads study bio-bank.
SNPs located in the coding region and 3'untranslated regions of RUNX1T1 with
minor allele frequency ≥0.05 were analysed using Taqman genotyping assays.
RESULTS: Eight candidate SNPs were genotyped successfully in 1440 participants.
Of these SNPs only rs34269950 located in the 'RRACH' motif, the most common
N6-methyladenosine (m6A) methylation modification site (recognized by FTO), was
significantly associated with obesity risk and metabolic abnormalities.
Specifically, compared to AA genotype, rs34269950 del/del genotype was
associated with a 1.47 [95% confidence interval (CI): 1.01-2.14, P = 0.042] fold
higher rate of obesity risk. Additionally, the del/del genotype was associated
with a 60% increased risk of metabolic syndrome (MetS) [odds ratio (OR) = 1.60,
95% CI: 1.10-2.32, P = 0.015], in comparison to the AA genotype. Finally,
rs34269950 del/del increased the risk of a larger waist circumference (OR =
1.65, 95% CI: 1.15-2.36, P = 0.007), but not other components of MetS.
CONCLUSION: Our study demonstrates that RUNX1T1 rs34269950, located in a
potential FTO recognition motif, is significantly associated with waist
circumference. This provides novel evidence to suggest SNPs located in RRACH
motif may be involved in RNA m6A modification and mechanistic pathways that
influence abdominal obesity. |
What is caused by SCUBE3 loss of function? | SCUBE3 loss-of-function causes a recognizable recessive developmental disorder due to defective bone morphogenetic protein signaling. | Author information:
(1)Department of Physiology, School of Medicine, Taipei Medical University,
110301 Taipei, Taiwan; Institute of Biomedical Sciences, Academia Sinica, 115201
Taipei, Taiwan.
(2)Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino
Gesù, IRCCS, 00146 Rome, Italy.
(3)Institute of Human Genetics, Julius Maximilians University, 97074 Würzburg,
Germany; Department of Otolaryngology - Head and Neck Surgery, Eberhard Karls
University, 72076 Tübingen, Germany.
(4)NIHR Oxford Biomedical Research Centre, Wellcome Centre for Human Genetics,
University of Oxford, OX3 7BN Oxford, UK.
(5)Genetics and Molecular Cell Sciences Research Centre, St George's University
of London, Cranmer Terrace, SW17 0RE London, UK.
(6)Centogene AG, 18055 Rostock, Germany.
(7)Department of Clinical Genetics, Leiden University Medical Center, 2300 RC
Leiden, the Netherlands.
(8)Department of Paediatric Endocrinology, Emma Children's Hospital, Amsterdam
University Medical Center, 1105 AZ Amsterdam, the Netherlands.
(9)Department of Cell and Molecular Biology & Microbiology, University of
Isfahan, 8174673441 Isfahan, Iran.
(10)Confocal Microscopy Core Facility, Research Laboratories, IRCCS Ospedale
Pediatrico Bambino Gesù, 00146 Rome, Italy.
(11)Department of Genetics, King Faisal Specialist Hospital and Research Center,
11211 Riyadh, Saudi Arabia; Qatar Biomedical Research Institute, Hamad Bin
Khalifa University, 34110 Doha, Qatar.
(12)Pediatric Endocrinology Unit, Ruth Rappaport Children's Hospital, Rambam
Healthcare Campus, 352540 Haifa, Israel; Ruth and Bruce Rappaport Faculty of
Medicine, Technion, Israel Institute of Technology, 352540 Haifa, Israel.
(13)Pediatric Endocrinology Unit, Ruth Rappaport Children's Hospital, Rambam
Healthcare Campus, 352540 Haifa, Israel.
(14)Edmond and Lily Safra Children's Hospital, Sheba Medical Center, 52621
Tel-Hashomer, Israel; The Sackler Faculty of Medicine, Tel-Aviv University,
6997801 Tel-Aviv, Israel.
(15)Department of Pediatric Endocrinology, Gaziantep Cengiz Gökcek Maternity &
Children's Hospital, 27010 Gaziantep, Turkey.
(16)Department of Pediatrics, Leiden University Medical Center, 2333ZA Leiden,
the Netherlands.
(17)Institute of Human Genetics, Julius Maximilians University, 97074 Würzburg,
Germany; Institute of Bioinformatics, Julius Maximilians University, 97070
Würzburg, Germany.
(18)Unidade de Endocrinologia Genética, Hospital das Clínicas da Faculdade de
Medicina da Universidade de Sao Paulo, 01246903 Sao Paulo, Brazil.
(19)Unidade de Genética do Instituto da Criança, Hospital das Clínicas da
Faculdade de Medicina da Universidade de Sao Paulo, 05403000 Sao Paulo, Brazil.
(20)Sheba Cancer Research Center, Sheba Medical Center, 52621 Tel-Hashomer,
Israel; Wohl Institute for Translational Medicine, Sheba Medical Center, 52621
Tel-Hashomer, Israel.
(21)Department of Clinical Genetics, Guy's and St Thomas' NHS Foundation Trust,
SE1 9RT London, UK; Birmingham Women's and Children's NHS Foundation Trust,
University of Birmingham, B4 6NH Birmingham, UK.
(22)Department of Paediatrics, Sheikh Khalifa Medical City, 51900 Abu Dhabi,
United Arab Emirates.
(23)Johns Hopkins Aramco Healthcare, 34465 Dhahran, Saudi Arabia.
(24)Department of Clinical Genetics, Guy's and St Thomas' NHS Foundation Trust,
SE1 9RT London, UK.
(25)Edmond and Lily Safra Children's Hospital, Sheba Medical Center, 52621
Tel-Hashomer, Israel; The Sackler Faculty of Medicine, Tel-Aviv University,
6997801 Tel-Aviv, Israel; Wohl Institute for Translational Medicine, Sheba
Medical Center, 52621 Tel-Hashomer, Israel.
(26)Department of Medical Genetics, Kasturba Medical College, Manipal Academy of
Higher Education, Manipal 576104, India.
(27)Institute of Human Genetics, Julius Maximilians University, 97074 Würzburg,
Germany.
(28)Department of Genetics, King Faisal Specialist Hospital and Research Center,
11211 Riyadh, Saudi Arabia.
(29)Institute of Biomedical Sciences, Academia Sinica, 115201 Taipei, Taiwan;
Ph.D. Program in Drug Discovery and Development Industry, College of Pharmacy,
Taipei Medical University, 110301 Taipei, Taiwan; Institute of Pharmacology,
School of Medicine, National Yang-Ming University, 112304, Taipei, Taiwan.
Electronic address: [email protected].
(30)Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino
Gesù, IRCCS, 00146 Rome, Italy. Electronic address: [email protected]. |
Which drugs are included in the CAPOX chemotherapy regimen for colorectal cancer? | CAPOX chemotherapy regimen for colorectal cancer includes capecitabine plus oxaliplatin. | BACKGROUND: Cetuximab is an IgG1 monoclonal antibody targeting the epidermal
growth factor receptor and is able to reverse the resistance to irinotecan in
patients with metastatic colorectal cancer (mCRC). This phase II trial evaluates
the safety and efficacy of cetuximab combined with capecitabine and oxaliplatin
(CAPOX) in the treatment of patients with mCRC progressing under
oxaliplatin-based chemotherapy.
PATIENTS AND TREATMENT: Forty patients with mCRC were treated with cetuximab
(loading dose 400 mg/m(2) and then 250 mg/m(2) i.v. weekly) in combination with
CAPOX (d(1): L-OHP 85 mg/m(2) and d(1-7) capecitabine 2000 mg/m(2) every 2
weeks). Thirty-one (77.5%) and nine (22.5%) patients had oxaliplatin-refractory
and -resistant disease, respectively; in addition, 32 (80%) patients had also
progressed on prior irinotecan-based chemotherapy.
RESULTS: One hundred and thirty-four cycles were administered (median of four
cycles per patient). Main toxic effects included grade 3-4 neutropenia (12.5%),
grade 3/4 diarrhea (7.5%), grade 3 fatigue (2.5%), and grade 2-3 neurotoxicity
(22.5%). One (2.5%) complete and seven (17.5%) partial responses were achieved
[overall objective response rate (ORR): 20%; 95% confidence interval (CI): 9% to
32%)], whereas 11 (27.5%) patients had stable disease [disease control rate
(DCR): 47.5%; 95% CI: 30.2% to 64.5%]. The ORR and DCR were 18.7% and 46.8%,
respectively, in patients with oxaliplatin-refractory disease. The median time
to tumor progression was 3 months, the median survival 10.7 months and the
probability of 1-year survival rate 53.4%.
CONCLUSIONS: The combination of cetuximab plus CAPOX is safe and has a promising
activity in patients with mCRC refractory or resistant to oxaliplatin. Colorectal cancer is the second most common site of cancer for both men and
women in New Zealand (NZ). Survival, especially with metastatic disease, has
improved considerably over the last decade with the introduction of new
chemotherapeutic agents. A questionnaire-based survey was conducted to document
variations in chemotherapy prescription patterns throughout NZ. Out of 25
medical oncologists, responses were obtained from 22 (88%). The patient with
stage III colon cancer was offered either 5-fluorouracil/leucovorin, most
commonly on the weekly bolus schedule, or capecitabine monotherapy. Chemotherapy
was also offered by the majority (65%) of respondents to the patient with
'high-risk' stage II colon cancer. Several chemotherapy combinations are
available in NZ in the metastatic setting, with the most popular being
oxaliplatin/capecitabine combination (CAPOX) (35%) or irinotecan/5-FU
combination (FOLFIRI) (23%). None of the respondents would commence chemotherapy
solely on the basis of a rising carcinoembryonic antigen (CEA). Two-thirds of
respondents would recommend chemotherapy for the patient with resectable liver
metastases, either before or after surgery. Our survey indicates that
chemotherapy prescriptions for patients with colon cancer in NZ, though not
uniform, are mostly in line with international recommendations. Colorectal cancer (CRC) is a worldwide public health problem, with nearly
800,000 new cases diagnosed each year, resulting in approximately 500,000
deaths. When advanced metastatic disease is diagnosed, CRC is associated with a
poor prognosis, and 5-year survival rates are in the range of 5%-8%.
Chemotherapy has been the mainstay approach for patients with advanced CRC. For
nearly 40 years, the main drug used for this disease was the fluoropyrimidine
5-fluorouracil (5-FU). Significant advances have been made in chemotherapy
treatment options for patients with metastatic disease, such that improvements
in 2-year survival are now being reported with median survival rates of 21
months to 24 months. Over the past 10 years, 3 new cytotoxic chemotherapy agents
have been approved by the FDA for metastatic CRC. These compounds include the
topoisomerase I inhibitor irinotecan, the third-generation platinum analogue
oxaliplatin, and the oral fluoropyrimidine capecitabine. Since 2004, 3 novel
biologic agents have been approved by the FDA, and they include the
anti-epidermal growth factor receptor antibodies cetuximab and panitumumab and
the anti-vascular endothelial growth factor bevacizumab. The oral
fluoropyrimidine capecitabine has been effectively and safely combined with
irinotecan (CAPIRI) and/or oxaliplatin (CAPOX). Three randomized phase III
studies have now shown that CAPOX is equivalent to FOLFOX
(5-FU/leucovorin/oxaliplatin)-based regimens. Significant interest has centered
around combining capecitabine-based cytotoxic regimens with the biologic agents,
and specifically, bevacizumab and cetuximab. This review will update the current
status of these capecitabine-based combination regimens. BACKGROUND: To evaluate the efficacy and tolerance of capecitabine (CAP) given
every other week and biweekly oxaliplatin (OX; modified CAPOX regimen) in
patients with advanced colorectal cancer previously treated with irinote-
can-based frontline chemotherapy.
METHODS: Sixty-seven patients were enrolled; the median age was 62 years and 62
(92.5%) had a performance status (ECOG) of 0-1. OX and CAP were administered at
the dose of 100 mg/m(2) on day 1 and 2,000 mg/m(2) on days 1-7, respectively,
every 2 weeks.
RESULTS: A total of 429 treatment cycles were administered. Grade 3/4
neutropenia and thrombocytopenia were observed in 4 (6%) and 2 (3%) patients,
respectively. Febrile neutropenia complicated 1 treatment cycle. The main
nonhematologic toxicities were grade 2/3 peripheral sensory neurotoxicity (10%
of patients) and grade 3/4 diarrhea (7%). In an intention-to-treat analysis, 3
(4.5%) complete and 13 (19.4%) partial responses (overall response rate 24%)
were observed. Seventeen (24.5%) patients had stable and 27 (40.3%) progressive
disease. The median time to tumor progression and overall survival were 5 months
and 11.3 months, respectively.
CONCLUSIONS: The results indicate that the modified CAPOX regimen is safe and
effective as salvage treatment in patients with advanced colorectal cancer who
were previously treated with irinotecan-based frontline therapy. Colon cancer with DNA mismatch repair (MMR) defects reveals distinct clinical
and pathologic features, including a better prognosis but reduced response to
5-fluorouracil (5-FU)-based chemotherapy. A current standard treatment for
recurrent or metastatic colon cancer uses capecitabine plus oxaliplatin (CAPOX),
or continuous-infusion fluorouracil plus oxaliplatin (FOLFOX). This study
investigated the effect of MMR status on the treatment outcomes for CAPOX and
FOLFOX as first-line combination chemotherapy in recurrent or metastatic colon
cancer. We analyzed 171 patients who had been treated with CAPOX or FOLFOX as
first-line combination chemotherapy in recurrent or metastatic colon
adenocarcinoma between February 2004 and July 2008. Tumor expression of the MMR
proteins, MLH1 and MSH2, was detected by immunohistochemistry (IHC) in
surgically resected tumor specimens. The microsatellite instability (MSI) was
analyzed by polymerase chain reaction (PCR) amplification, using fluorescent
dye-labeled primers specific to microsatellite loci. Tumors with MMR defect were
defined as those demonstrating a loss of MMR protein expression (MMR-D) and/or a
microsatellite instability-high (MSI-H) genotype. In all, 75 patients (44%)
received FOLFOX, and 96 patients (56%) received CAPOX as first-line combination
chemotherapy. The incidence of colon cancer with MMR defect was 10/171 (6%).
Colon cancers with MMR defect (MSI-H and/or MMR-D) are more commonly located in
proximal to the splenic flexure (p=0.03). The MMR status did not significantly
influence the overall response (p=0.95) to first-line CAPOX or FOLFOX treatment
in patients with recurrent or metastatic colon cancer. According to the MMR
status, there was no significant difference for PFS (p=0.50) and OS (p=0.47) in
patients with recurrent or metastatic colon cancer treated with first-line CAPOX
or FOLFOX. In colon cancers with MMR defect, there was no significant difference
for PFS (p=0.48) and OS (p=0.56) between CAPOX and FOLFOX as first-line
combination chemotherapy. However, in MMR intact, there was significant
difference for OS between CAPOX and FOLFOX (p=0.04). OS was significantly better
in patients treated with CAPOX when compared to patients with FOLFOX. The MMR
status does not predict the effect of oxaliplatin-based combination chemotherapy
as 1st line in recurrent or metastatic colon cancers. CAPOX in the first-line
treatment of recurrent or metastatic colon cancer with MMR intacts showed a
superior OS compared with FOLFOX unlike colon cancer with MMR defects. PURPOSE: Capecitabine has shown similar efficacy to 5-fluorouracil (5-FU); a
regimen containing 2 weeks of capecitabine/oxaliplatin (CapOx) has demonstrated
noninferiority to infusional 5-FU/oxaliplatin/leucovorin (FOLFOX) for the
treatment of metastatic colorectal cancer (mCRC). This phase II study explores
the efficacy and safety of a 2-day course of oxaliplatin/capecitabine (2DOC),
with oxaliplatin given on day 1 and capecitabine given orally every 8 hours in
high doses over 6 doses, mimicking FOLFOX6.
PATIENTS AND METHODS: This phase II study was conducted by the University of
Wisconsin Carbone Cancer Center. Eligible patients with mCRC received
oxaliplatin 100 mg/m2 intravenously (I.V.) over 2 hours followed by leucovorin
20 mg/m2 I.V. bolus and 5-FU 400 mg/m2 I.V. bolus on day 1 and day 15.
Capecitabine was administered at 1500 mg/m2 orally every 8 hours over 6 doses
starting on day 1 and day 15.
RESULTS: A total of 45 patients were enrolled; 44 were evaluated for response.
Seventeen patients (39%) had objective responses. Median time to progression was
6.8 months, and median overall survival (OS) was 17.5 months. The most common
side effects were grade 1/2 neuropathy, fatigue, and nausea. Severe hand-foot
syndrome (HFS) was rare.
CONCLUSION: The overall response rate with the 2DOC regimen is similar to
published CapOx regimens, and time to progression and OS are similar. The
incidence of HFS, diarrhea, and mucositis were lower compared with published
results of 2-week schedules of capecitabine. The 2DOC regimen merits further
study as a more convenient regimen than infusional 5-FU with less HFS when
compared with a 2-week administration of capecitabine. PURPOSE: The AIO KRK-0104 randomized phase II trial investigated the efficacy
and safety of cetuximab combined with capecitabine and irinotecan (CAPIRI) or
capecitabine and oxaliplatin (CAPOX) in the first-line treatment of metastatic
colorectal cancer (mCRC).
PATIENTS AND METHODS: A total of 185 patients with mCRC were randomly assigned
to cetuximab (400 mg/m(2) day 1, followed by 250 mg/m(2) weekly) plus CAPIRI
(irinotecan 200 mg/m(2), day 1; capecitabine 800 mg/m(2) twice daily days 1
through 14, every 3 weeks; or cetuximab plus CAPOX (oxaliplatin 130 mg/m(2) day
1; capecitabine 1,000 mg/m(2) twice daily day 1 through 14, every 3 weeks). The
primary study end point was objective response rate (ORR).
RESULTS: In the intention-to-treat patient population (n = 177), ORR was 46%
(95% CI, 35 to 57) for CAPIRI plus cetuximab versus 48% (95% CI, 37 to 59) for
CAPOX plus cetuximab. Analysis of the KRAS gene mutation status was performed in
81.4% of the intention to treat population. Patients with KRAS wild-type in the
CAPIRI plus cetuximab arm showed an ORR of 50.0%, a PFS of 6.2 months and an OS
of 21.1 months. In the CAPOX plus cetuximab arm, an ORR of 44.9%, a PFS of 7.1
months and an OS of 23.5 months were observed. While ORR and PFS were comparable
in KRAS wild-type and mutant subgroups, a trend toward longer survival was
associated with KRAS wild-type. Both regimens had manageable toxicity profiles
and were safe.
CONCLUSION: This randomized trial demonstrates that the addition of cetuximab to
CAPIRI or CAPOX is effective and safe in first-line treatment of mCRC. In the
analyzed regimens, ORR and PFS did not differ according to KRAS gene mutation
status. BACKGROUND: Despite lack of a true comparative study, the folfox
(5-fluorouracil-leucovorin-oxaliplatin) and capox (capecitabine-oxaliplatin)
regimens are believed to be similar in their efficacy and tolerability in the
treatment of stage iii colorectal cancer. However, that belief has been
disputed, because real-life data suggest that the capox regimen is more toxic,
leading to more frequent reductions in the delivered dose intensity-thus raising
questions about the effect of dose intensity on clinical outcomes.
METHODS: A retrospective data review for two Canadian institutions, the Segal
Cancer Centre and the Tom Baker Cancer Centre, considered patients diagnosed
with stage iii colorectal cancer during 2006-2013. Primary endpoints were dose
intensity and toxicity, with a secondary endpoint of disease-free survival.
RESULTS: The study enrolled 180 eligible patients (80 at the Segal Cancer
Centre, 100 at the Tom Baker Cancer Centre). Of those 180 patients, 75 received
capox, and 105 received mfolfox6. In the capox group, a significant dose
reduction was identified for capecitabine compared with 5-fluorouracil in
mfolfox6 group (p = 0.0014). Similarly, a significant dose reduction was
observed for oxaliplatin in mfolfox6 compared with oxaliplatin in capox (p =
0.0001). Compared with the patients receiving capox, those receiving mfolfox6
were twice as likely to experience a treatment delay of more than 1 cycle-length
(p = 0.03855). Toxicity was more frequent in patients receiving mfolfox6
(nausea: 30% vs. 18%; diarrhea: 47% vs. 24%; peripheral sensory neuropathy: 32%
vs. 3%). At a median follow-up of 40 months, preliminary data showed no
difference in disease-free survival (p = 0.598). Pooled data from both
institutions were also separately analyzed, and no significant differences were
found.
CONCLUSIONS: Our results support the use of capox despite a lack of head-to-head
randomized trial data. PURPOSE: Oxaliplatin, an important chemotherapeutic agent in colorectal cancer,
causes chemotherapy-induced peripheral neuropathy (CIPN), for which prophylactic
or therapeutic interventions are lacking. We aimed to investigate changes in
upper extremities, activities of daily living (ADL), and health-related quality
of life (HRQoL) parameters after the first chemotherapy cycle.
METHODS: Thirty-eight colorectal cancer patients scheduled to receive the
leucovorin, 5'-fluorouracil, oxaliplatin (FOLFOX) therapy or the capecitabine,
oxaliplatin (CAPOX) therapy, participated. Patients underwent objective
assessment of sensory function, muscular strength, and manual dexterity and
answered the European Organization for the Research and Treatment of Cancer
Quality of Life Questionnaire C30 (EORTC QLQ-C30) and the Disabilities of the
Arm, Shoulder, and Hand-Disability/Symptom (DASH-DS) questionnaires for
subjective assessment. The CIPN was assessed at baseline and prior to the second
drug cycle.
RESULTS: Light touch sensation in both hands worsened significantly after the
first drug cycle, though no significant changes were observed in muscular
strength and manual dexterity. The QLQ-C30 analysis showed that Physical
Functioning, Role Functioning, Nausea and Vomiting, and Dyspnea were
significantly worse, whereas Emotional Functioning was improved. The DASH-DS
analysis revealed significant worsening of dysfunction and subjective symptoms.
CONCLUSIONS: Our results suggest that light touch sensation may worsen even in
the absence of multiple chemotherapy cycles. Even if arm and hand function
(muscular strength and manual dexterity) is apparently intact, patients may
experience dysfunction and decreased HRQoL. For preserving or improving
patients' ADL and HRQoL, it is imperative to provide support at chemotherapy
initiation. BACKGROUND: Folate level was proposed to be a predictor for
fluoropyrimidine-related toxicity. We conducted a prospective study to determine
the association between serum and red-cell folate and capecitabine-related
toxicity in patients with colorectal cancers.
MATERIALS AND METHODS: Eligibility criteria included diagnosis of colorectal
cancers; eligible patients who were scheduled to undergo capecitabine
monotherapy or capecitabine-oxaliplatin (CAPOX) for adjuvant or palliative
purposes. Exclusion criteria included concomitant radiotherapy or chemotherapy
other than capecitabine or CAPOX and creatinine clearance <30 mL/min. Fasting
serum and red-cell folate were measured prior to chemotherapy. Capecitabine was
administered at 2,500 mg/m2 per day (monotherapy) or 2,000 mg/m2 per day (CAPOX)
for 14 days every 3 weeks. The toxicity of the first four cycles was documented
by clinical investigators who were blinded to folate levels.
RESULTS: A total of 144 patients were recruited, of whom 126 were eligible; 40
patients had capecitabine alone, and 86 patients received CAPOX. The rates of
grade 2 and grade 3 toxicity were 63.5% and 14.3%, respectively. Nausea and
vomiting were the most common grade ≥2 adverse event (47.7%), followed by
hand-foot syndrome (25.4%), diarrhea (23.1%), and neutropenia (22.3%).
Combination with oxaliplatin (odds ratio [OR], 2.77; p = .043) and serum folate
(OR, 10.33; p = .002) were independent predictors of grade ≥2 toxicity. Red-cell
folate was not predictive of toxicity. For every 10 nmol/L increment in serum
folate, the risk of grade ≥2 toxicity increased by 9%.
CONCLUSION: Serum folate level, but not red-cell folate, was associated with
higher rate of grade ≥2 toxicity during capecitabine-based treatment. Excessive
folate intake may be avoided before and during capecitabine-based chemotherapy.
IMPLICATIONS FOR PRACTICE: This is the first prospective study to evaluate the
association between serum folate level and capecitabine-related toxicity in
patients with colon cancers. It shows that higher serum folate level is
associated with increased risks of moderate to severe toxicity during
capecitabine-based treatment. Excessive folate intake should be avoided before
and during capecitabine-based chemotherapy. BACKGROUND Colorectal cancer (CRC) is considered to be a worldwide health
problem because of its increasing incidence and prevalence. Surgery offers an
opportunity for cure, but the postoperative recurrence rate is still high
despite the advancement of chemotherapy. This study aimed to assess the efficacy
and safety of prolonged capecitabine chemotherapy following CAPOX chemotherapy
for stage III CRC after radical surgery. MATERIAL AND METHODS This study
included 212 patients with stage III CRC undergoing open radical surgery from
July 2010 to June 2015. Among those patients, 104 patients received prolonged
capecitabine chemotherapy (prolonged group) following 8 cycles of CAPOX regimen
chemotherapy, while the other 108 patients (control group) received no prolonged
chemotherapy. The prolonged chemotherapy consisted of capecitabine (1000 mg/m²
per day for 2 weeks) and was repeated every 3 weeks for 8 cycles at most.
Long-term survival and toxicities were retrospectively compared. RESULTS Patient
characteristics did not differ between the 2 groups. For all patients, no
significant difference was found in the 3-year disease-free survival (DFS)
(P=0.7775) or 3-year overall survival (OS) rates between the 2 groups
(P=0.5787). The prolonged group had significantly higher frequency of hand-foot
syndrome (P=0.0267) and paresthesia (P=0.0164). In further subgroup analyses, no
benefit for 3-year DFS or 3-year OS of prolonged capecitabine chemotherapy was
found in colon cancer or rectal cancer. CONCLUSIONS Prolonged capecitabine
chemotherapy following CAPOX regimen chemotherapy failed to improve the survival
of patients with stage III CRC after radical surgery. IMPORTANCE: The addition of oxaliplatin to the standard 6-month
fluorouracil-based adjuvant chemotherapy in stage II colorectal cancer has been
reported to reduce the risk of relapse although it does not increase survival.
The Three or Six Colon Adjuvant (TOSCA) trial compared 3 months with 6 months of
adjuvant fluoropyrimidine and oxaliplatin-based chemotherapy in patients with
stage III colon cancer. The utility remains unknown.
OBJECTIVE: To assess the noninferiority and toxic effects of 3 vs 6 months of
FOLFOX (fluorouracil, leucovorin, and oxaliplatin) or CAPOX (capecitabine plus
oxaliplatin) adjunct chemotherapy among patients with high-risk stage II
resected colorectal cancer enrolled in the TOSCA trial.
DESIGN, SETTING, AND PARTICIPANTS: The TOSCA study was a noninferiority phase 3
randomized clinical trial conducted from June 2007 to March 2013 in 130 Italian
centers. Included patients had resected colorectal cancer located 12 cm from the
anal verge by endoscopy or above the peritoneal reflection at surgery. In this
preplanned study assessing the per-protocol population, 5-year relapse-free
survival was evaluated in 1254 patients with high-risk stage II resected
colorectal cancer who had received adjuvant FOLFOX (fluorouracil, leucovorin,
and oxaliplatin) or CAPOX (capecitabine plus oxaliplatin).
INTERVENTIONS: Patients were originally randomized (1:1) in the TOSCA trial to
receive 3 months (experimental group) or 6 months (control) of standard doses of
FOLFOX or CAPOX at the discretion of the treating physician.
MAIN OUTCOME AND MEASURES: A hazard ratio of at least 1.2 between the 3-month
and 6-month chemotherapy groups was set to reject the null hypothesis of
noninferiority.
RESULTS: Overall, 1254 patients (mean [SD] age, 62.4 [9.8] years; 565 women
[45.1%]) with clinical high-risk stage II resected colorectal cancer were
analyzed at a median follow-up of 62 months (interquartile range, 53-71) months.
Of them, 301 patients (24.0%) had pT4N0M0 tumors, and the remaining 953 patients
(76.0%) had high-risk pT3N0M0 tumors; 776 patients (61.9%) received FOLFOX and
478 (38.1%) received CAPOX. The 5-year relapse-free survival was 82.2% for the
3-month arm and 88.2% for the 6-month arm, with an estimated hazard ratio of
1.41 (95% CI, 1.05-1.89; P = .86 for noninferiority). For CAPOX, the 5-year
relapse-free survival was similar in the 2 arms (difference, 0.76% favoring the
6-month arm; 95% CI, -6.28% to 7.80%), whereas for FOLFOX, the difference was
pronounced: 8.56% in favor of the longer-duration arm (95% CI, 3.45%-13.67%).
Nevertheless, the test for an interaction between duration and regimen was not
statistically significant. Neurotoxicity was approximately 5 times lower in the
shorter duration arm than in the longer duration arm.
CONCLUSIONS AND RELEVANCE: In the 3-month arm, the treatment was significantly
less toxic than in the 6-month arm. Noninferiority was not shown for 5-year
relapse-free survival. However, a possible regimen effect was observed,
suggesting that either 3 months of CAPOX or 6 months of FOLFOX therapy can be
used whenever an oxaliplatin doublet is indicated for treatment of patients with
stage II colorectal cancer.
TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT0064660. A 74-year-old man underwent distal gastrectomy for gastric cancer(CY1, fStage
Ⅳ). About 18 months after surgery, abdominal CT scans revealed multiple lymph
node metastases along the portal vein. Systemic chemotherapy was administered
comprising a capecitabine/oxaliplatin(CAPOX)regimen. After 4 courses of
chemotherapy, an adverse reaction of Grade 2 diarrhea and peripheral neuropathy
occurred, although regression of the lymph node metastasis was confirmed.
Ramucirumab was administered as the second-line regimen, but CT imaging revealed
lymph node progression after several courses. Although irinotecan(CPT-11)was
selected as the third-line chemotherapy, the lymph node progression remained
uncontrolled. Nivolumab was selected as the fourth-line chemotherapy. After 23
courses, nivolumab immunotherapy induced a partial response to the lymph node
metastasis. Nivolumab immunotherapy continues to be administered until now, 5
years after the operation. We experienced a case of lymph node metastasis from
gastric cancer successfully treated with nivolumab chemotherapy. WHAT IS KNOWN AND OBJECTIVE: High interindividual response variability was
reported with capecitabine and oxaliplatin (CAPOX) regimen in colorectal cancer
(CRC). The single nucleotide polymorphisms (SNPs) of the genes related to drug
efflux transport (ABCB1) and DNA repair (ERCC) could result in altered tumour
response. Hence, this study was designed to assess the influence of ABCB1,
ERCC-1 and ERCC-2 gene polymorphisms on tumour response to CAPOX treatment in
CRC patients of South Indian origin.
PATIENTS AND METHODS: A total of 145 newly diagnosed CRC patients were included
in the final analysis. Response to CAPOX treatment in the adjuvant setting was
assessed in terms of disease-free survival rate (DFSR) and overall survival rate
(OSR) at 3 years, whereas in the palliative setting, the response was assessed
as progression-free survival rate (PFSR) and OSR at 3 years. Five millilitres of
the venous blood sample was collected from each patient for genomic DNA
extraction by the manual phenol-chloroform method. Genotyping and allelic
discrimination analysis were done using real-time PCR (RT-PCR).
RESULTS AND DISCUSSION: With ABCB1 gene polymorphism rs1045642 (A > G), patients
with AG/GG genotype showed better DFSR [P value = .02, OR = 2 (CI: 1.5-3)] and
PFSR [P value = .02, OR = 1.6 (CI: 1.1-2.5)] when compared to AA genotype in the
adjuvant and palliative settings, respectively. Similarly with rs1128503 (A > G)
polymorphism, patients with AG/GG genotype were found to have better DFSR [P
value = .02, OR = 1.9 (CI: 1.3-3)] and PFSR [P value = .01, OR = 2 (CI:
1.1-3.7)] when compared to AA genotype. However, we did not find any association
between CAPOX response and ABCB1 gene polymorphisms in a binary logistic
regression when non-genetic predictors were considered for analysis. We did not
find any association with ERCC1 (rs11615 A > G) and ERCC2 (rs13181 T > G) gene
polymorphisms with respect to CAPOX response in either of the treatment
settings.
WHAT IS NEW AND CONCLUSION: The response to CAPOX treatment was found to be
influenced by the ABCB1 gene variants (rs1128503 and rs1045642), thereby
strengthening their predictive role. No association was found between ERCC1
(rs11615 A > G), ERCC2 (rs13181 T > G) gene polymorphisms and tumour response to
CAPOX treatment in CRC patients of South Indian origin. Colorectal cancer is one of the most common maligcies diagnosed in Canada.
Currently, adjuvant colorectal cancer treatment primarily includes
chemotherapeutic regimens such as FOLFOX6 (5-fluorouracil, leucovorin,
oxaliplatin) or CAPOX (capecitabine, oxaliplatin), as well as alternative
regimens such as TOMOX (raltitrexed, oxaliplatin). However, the prevalence of
drug shortages in today's society may make these preferred regimens
inaccessible. The purpose of this case report is to highlight the tolerability
of an alternative adjuvant regimen (pemetrexed plus oxaliplatin) that has
undergone both phase I and II clinical trials for the treatment of colorectal
cancer. The patient presented in this case report is a 57-year-old female
diagnosed with Stage III colon cancer. This patient received seven cycles of
pemetrexed plus oxaliplatin and experienced several adverse events, with the
majority of them being mild in nature including fatigue and cold dysesthesia.
However, the patient also experienced progressive neuropathy which required a
dose reduction and subsequent discontinuation of oxaliplatin. Overall,
pemetrexed and oxaliplatin's tolerability seems comparable to other regimens
used to treat colorectal cancer and could potentially be an option to consider
in the future for alternative treatment of colorectal cancer pending further
trials. OBJECTIVE: To assess the effectiveness and safety of treatment consisting of
extending chemotherapy (ECT) with capecitabine following capecitabine plus
oxaliplatin (CAPOX) chemotherapy for stage 3 gastric carcinoma (GC) after D2
gastrectomy.
PATIENTS AND METHODS: In this retrospective study, we included 214 patients with
stage 3 GC who underwent D2 gastrectomy between January 2012 and April 2014. The
CAPOX regimen chemotherapy was administrated to all of the patients as adjuvant
therapy. The CAPOX regimen consisted of capecitabine (1000 mg/m2, in 2 divided
doses for 14 d) and oxaliplatin (130 mg/m2 given on Day 1), repeated every 21 d
for 8 cycles. Following CAPOX chemotherapy, 102 of these patients received
extending chemotherapy (the ECT group) with capecitabine, whereas 112 patients
(the control group) received no ECT. The ECT consisted of capecitabine (1000
mg/m2, in 2 divided doses for 14 d), repeated every 21 d for 8 cycles at most.
The chemotherapy was discontinued if unacceptable toxicity or disease
progression occurred or upon the request of the patient. All cases were followed
up, and overall survival (OS), recurrence-free survival (RFS), and toxicities
were compared.
RESULTS: The ECT group exhibited a distinctly higher 5-year OS (p=0.0468) and
RFS (p=0.0483) than those of the control group. The incidence of hand-foot
syndrome was markedly greater in the ECT group (p=0.0043). No toxicity-related
death occurred.
CONCLUSIONS: Extending chemotherapy with capecitabine following the CAPOX
regimen chemotherapy provides significant survival benefit for stage 3 GC after
D2 gastrectomy. Conflict of interest statement: Conflict of interest statement G.N. reports
receiving honoraria from Chugai, Janssen, Yakult Honsha, Taiho, Eli Lilly,
Miyarinsan and Takeda and research funding to his institution from Eli Lilly,
outside the submitted work. H.T. reports receiving honoraria from Bayer,
Bristol-Myers Squibb, Chugai, Daiichi Sankyo, Eli Lilly, MBL, Merck Bio Pharma,
Mitsubishi Tanabe Pharma, MSD, Nippon Kayaku, Novartis, Sanofi, Taiho, Takeda
and Yakult Honsha and research funding to his institution from Daiichi Sankyo,
Isofol, MSD, Novartis, Ono, Pfizer, Sumitomo Dainippon Pharma, Sysmex and
Takeda, outside the submitted work. K.U. reports receiving honoraria from Eli
Lilly and Chugai, outside the submitted work. K.M. reports receiving honoraria
from Chugai, outside the submitted work. M.A. reports receiving grant from Kyowa
Kirin, outside the submitted work. Y.A. reports receiving grants and personal
fees from Chugai, Kyowa Hakko Kirin, Nippon Kayaku, Yakult Honsha, Mochida, Ono,
Taiho and Daiichi Sankyo; personal fees from Eli Lilly, Novartis, Bayer,
Bristol-Myers Squibb, Sawai, Tsumura and Shionogi and grants from Eisai, outside
the submitted work. K.M. reports receiving grants from Daiichi Sankyo, Parexel
International, Shionogi Pharma, Sumitomo Dainippon, MSD, Pfizer, Mediscience
Planning and Solasia Pharma; grants and personal fees from Ono and Sanofi and
personal fees from Takeda, Taiho, Bristol-Myers Squibb, Bayer, Eli Lilly and
Chugai, outside the submitted work. Y.K. reports receiving honoraria from Taiho,
Ono, Daiichi Sankyo, Eli Lilly, Chugai, Yakult Honsha, MSD, Nippon Kayaku,
Sawai, Tsumura and Miyarinsan and research funding to his institution from
Taiho, Chugai, Eli Lilly, Sanofi, Nippon Kayaku, Ono, Otsuka, Takeda, MSD and
Pfizer, outside the submitted work. LESSONS LEARNED: Three-month adjuvant capecitabine plus oxaliplatin in
combination (CAPOX) appeared to reduce recurrence, with mild toxicity in
postcurative resection of colorectal cancer liver metastases (CLM). Recurrence
in patients who underwent the 3-month adjuvant CAPOX after resection of CLM was
most commonly at extrahepatic sites.
BACKGROUND: The role of neoadjuvant and adjuvant chemotherapy in the management
of initially resectable colorectal cancer liver metastases (CLM) is still
unclear. We evaluated the feasibility of 3-month adjuvant treatment with
capecitabine plus oxaliplatin in combination (CAPOX) for postcurative resection
of CLM.
METHODS: Patients received one cycle of capecitabine followed by four cycles of
CAPOX as adjuvant chemotherapy after curative resection of CLM. Oral
capecitabine was given as 1,000 mg/m2 twice daily for 2 weeks in a 3-week cycle,
and CAPOX consisted of oral capecitabine plus oxaliplatin 130 mg/m2 on day 1 in
a 3-week cycle. Primary endpoint was the completion rate of adjuvant
chemotherapy. Secondary endpoints included recurrence-free survival (RFS),
overall survival (OS), dose intensity, and safety.
RESULTS: Twenty-eight patients were enrolled. Median age was 69.5 years, 54% of
patients had synchronous metastases, and 29% were bilobar. Mean number of
lesions resected was two, and mean size of the largest lesion was 31 mm. Among
patients, 20 (71.4%; 95% confidence interval, 53.6%-89.3%) completed the
protocol treatment and met its primary endpoint. The most common grade 3 or
higher toxicity was neutropenia (29%). Five-year recurrence-free survival and
overall survival were 65.2% and 87.2%, respectively.
CONCLUSION: Three-month adjuvant treatment with CAPOX is tolerable and might be
a promising strategy for postcurative resection of CLM. BACKGROUND: At present, colorectal cancer is routinely treated with adjuvant
radiotherapy and chemotherapy postoperatively. The adverse effects (AEs) of
chemotherapy usually interrupt the treatment of chemotherapy. Traditional
Chinese medicine (TCM) has demonstrated great potential in improving patients'
clinical symptoms, regulating the immune function, improving the life quality,
and reducing the AEs of chemotherapy.
AIM: To observe the clinical efficacy of Yiqi Jianpi anti-cancer prescription
combined with chemotherapy in patients with colorectal cancer after operation.
METHODS: Data from patients diagnosed with colorectal cancer between January
2019 and February 2021 were collected from Liaoning Cancer Hospital and
Institute and the Second Affiliated Hospital of Liaoning University of
Traditional Chinese Medicine. Patients receiving the chemotherapy regimen of
capecitabine plus oxaliplatin (CAPOX) after radical resection of colorectal
cancer were prospectively collected and randomly divided into an experimental
group and a control group. The experimental group was given Yiqi Jianpi
anti-cancer prescription combined with the CAPOX regimen, while the control
group was given the CAPOX regimen alone. After six cycles of chemotherapy, the
scores of TCM symptoms, Karnofsky performance scale (KPS) score, levels of
T-cell subsets, and AEs after chemotherapy of the two groups were compared.
RESULTS: A total of 70 patients were randomly divided into either an
experimental group (n = 35, no dropout) or a control group (n = 33, with 2
dropouts). Compared with the control group, the experimental group improved
significantly (P < 0.05) in scores of TCM symptoms, KPS score, levels of T-cell
subsets, and AEs of chemotherapy.
CONCLUSION: Yiqi Jianpi anti-cancer prescription can effectively improve spleen
deficiency, regulate the immune function, and alleviate the AEs of chemotherapy,
so as to improve the life quality of patients with good therapeutic effects and
application prospect in clinical practice. |
Is FKBP52 encoding a chaperone ? | Yes,
FKBP52 is a co-chaperone. | The present study aimed to examine the expression of FK‑506 binding protein 52
(FKBP52) in the ovary tissues of rats with polycystic ovarian syndrome (PCOS)
and its action on mediating androgen receptor (AR) through the mitogen‑activated
protein kinase (MAPK)/extracellular signal‑regulated kinase (ERK) pathway. PCOS
model rats were established by dehydroepiandrosterone injection. Enzyme‑linked
immunosorbent assay (ELISA) measured serum sex hormones. Hematoxylin and eosin
(H&E) staining was used to examine histological changes of the ovarian tissues.
The expression levels of FKBP52 were detected by immunohistochemical (IHC)
staining, reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR)
analysis and western blotting (WB). In addition, RT‑qPCR analysis was used to
detect the mRNA expression of AR, and WB was used to detect the protein
expression levels of AR, ERK1/2 and phosphorylated (p‑)ERK1/2. In granulosa cell
(GC) experiments, primary GCs were extracted and cultured. FKBP4 is the
FKBP52‑encoding gene, therefore, adenovirus vectors Ad‑Oe‑FKBP4‑EGFP and
Ad‑siRNA‑FKBP4‑EGFP were constructed to examine the association among the above
factors using the RT‑qPCR and WB methods. In the animal experiment, the vaginal
smear, H&E staining and ELISA results showed that the PCOS model was
successfully established. The IHC staining revealed that the expression of
FKBP52 in the GCs of the PCOS model group was higher than the remaining groups
(P<0.01). The mRNA and expression levels of FKBP52 and AR in the PCOS model rats
were significantly increased, when compared with levels in the other rats
(P<0.05). The expression level of p‑ERK1/2 was also higher (P<0.05). In the GC
experiment, following overexpression of the FKBP4 gene, the mRNA and expression
levels of FKBP52 and AR were increased (P<0.05). The expression level of
p‑ERK1/2 was also increased (P<0.05). Following FKBP4 gene silencing, the mRNA
and expression levels of FKBP52 and AR were decreased (P<0.05). The expression
level of ERK1/2 was also decreased (P<0.05). However, the expression level of
p‑ERK1/2 was increased (P<0.05). In conclusion, the upregulation of co‑chaperone
FKBP52 may mediate the activation of AR through the MAPK/ERK pathway. BACKGROUND: Stress exposure as well as psychiatric disorders are often
associated with abnormalities in brain structure or connectivity. The
co-chaperone FK506-binding protein 51 (FKBP51) is a regulator of the stress
system and is associated with a risk to develop stress-related mental illnesses.
PURPOSE: To assess the effect of a general FKBP51 knockout on brain structure
and connectivity in male mice.
STUDY TYPE: Animal study.
ANIMAL MODEL: Two cohorts of FKBP51 knockout (51KO) and wildtype (WT) mice. The
first cohort was comprised of n = 18 WT and n = 17 51KOs; second cohort n = 10
WT and n = 9 51KOs.
FIELD STRENGTH/SEQUENCE: 9.4T/3D gradient echo (VBM), DTI-EPI (DTI).
ASSESSMENT: Voxel-based morphometry (VBM) and diffusion tensor imaging (DTI).
For VBM, all procedures were executed in SPM12. DTI: FMRIB Software Library
(FSL) Tract Based Statistics (TBSS) were integrated within DTI-TK, allowing the
creation of a mean FA skeleton. A voxelwise statistical analysis was applied
between WT and 51KO mice.
STATISTICAL TEST: Volumetric differences were collected at a threshold of
P < 0.005, and only clusters surviving a familywise error correction on the
cluster level (pFWE, cluster <0.05) were further considered. VBM data were
analyzed using a two-sample t-test. The Threshold Free Cluster Enhancement
(TFCE) method was used to derive uncorrected-P statistical results at a P-level
of 0.01.
RESULTS: The structural analysis revealed two clusters of significantly larger
volumes in the hypothalamus, periaqueductal gray, and dorsal raphe region of WT
animals. DTI measurements, however, demonstrated statistically higher fractional
anisotropy (FA) values for 51KO animals in locations including the anterior
commissure, fornix, and posterior commissure/superior colliculus commissure
region.
DATA CONCLUSION: This study used in vivo structural MRI and DTI to demonstrate
that a lack of FKBP51 leads to alterations in brain architecture and
connectivity in male mice. These findings are of particular translational
relevance for our understanding of the neuroanatomy underlying the interaction
of FKBP5 genetic status, stress susceptibility, and psychiatric disorders.
LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 1. |
Isotocin is an homolog of what hormone? | Isotocin is a homolog of oxytocin. | A wide range of physiological and behavioral processes, such as social, sexual,
and maternal behaviors, learning and memory, and osmotic homeostasis are
influenced by the neurohypophysial peptides oxytocin and vasopressin.
Disruptions of these hormone systems have been linked to several neurobehavioral
disorders, including autism, Prader-Willi syndrome, affective disorders, and
obsessive-compulsive disorder. Studies in zebrafish promise to reveal the
complex network of regulatory genes and signaling pathways that direct the
development of oxytocin- and vasopressin-like neurons, and provide insight into
factors involved in brain disorders associated with disruption of these systems.
Isotocin, which is homologous to oxytocin, is expressed early, in a simple
pattern in the developing zebrafish brain. Single-minded 1 (sim1), a member of
the bHLH-PAS family of transcriptional regulatory genes, is required for
terminal differentiation of mammalian oxytocin cells and is a master regulator
of neurogenesis in Drosophila. Here we show that sim1 is expressed in the
zebrafish forebrain and is required for isotocin cell development. The
expression pattern of sim1 mRNA in the embryonic forebrain is dynamic and
complex, and overlaps with isotocin expression in the preoptic area. We provide
evidence that the role of sim1 in zebrafish neuroendocrine cell development is
evolutionarily conserved with that of mammals. BACKGROUND: The mammalian neurohypophysial hormones, vasopressin and oxytocin
are involved in osmoregulation and uterine smooth muscle contraction
respectively. All jawed vertebrates contain at least one homolog each of
vasopressin and oxytocin whereas jawless vertebrates contain a single
neurohypophysial hormone called vasotocin. The vasopressin homolog in
non-mammalian vertebrates is vasotocin; and the oxytocin homolog is mesotocin in
non-eutherian tetrapods, mesotocin and [Phe2]mesotocin in lungfishes, and
isotocin in ray-finned fishes. The genes encoding vasopressin and oxytocin genes
are closely linked in the human and rodent genomes in a tail-to-tail
orientation. In contrast, their pufferfish homologs (vasotocin and isotocin) are
located on the same strand of DNA with isotocin gene located upstream of
vasotocin gene separated by five genes, suggesting that this locus has
experienced rearrangements in either mammalian or ray-finned fish lineage, or in
both lineages. The coelacanths occupy a unique phylogenetic position close to
the divergence of the mammalian and ray-finned fish lineages.
RESULTS: We have sequenced a coelacanth (Latimeria menadoensis) BAC clone
encompassing the neurohypophysial hormone genes and investigated the
evolutionary history of the vertebrate neurohypophysial hormone gene locus
within a comparative genomics framework. The coelacanth contains vasotocin and
mesotocin genes like non-mammalian tetrapods. The coelacanth genes are present
on the same strand of DNA with no intervening genes, with the vasotocin gene
located upstream of the mesotocin gene. Nucleotide sequences of the second exons
of the two genes are under purifying selection implying a regulatory function.
We have also analyzed the neurohypophysial hormone gene locus in the genomes of
opossum, chicken and Xenopus tropicalis. The opossum contains two tandem copies
of vasopressin and mesotocin genes. The vasotocin and mesotocin genes in chicken
and Xenopus, and the vasopressin and mesotocin genes in opossum are linked
tail-to-head similar to their orthologs in coelacanth and unlike their homologs
in human and rodents.
CONCLUSION: Our results indicate that the neurohypophysial hormone gene locus
has experienced independent rearrangements in both placental mammals and teleost
fishes. The coelacanth genome appears to be more stable than mammalian and
teleost fish genomes. As such, it serves as a valuable outgroup for studying the
evolution of mammalian and teleost fish genomes. The present study using zebrafish as a model explores the role of isotocin, a
homolog of oxytocin, in controlling ion regulatory mechanisms. Double-deionized
water treatment for 24 h significantly stimulated isotocin mRNA expression in
zebrafish embryos. Whole-body Cl(-), Ca(2+), and Na(+) contents, mRNA
expressions of ion transporters and ionocyte-differentiation related
transcription factors, and the number of skin ionocytes decreased in isotocin
morphants. In contrast, overexpression of isotocin caused an increase in
ionocyte numbers. Isotocin morpholino caused significant suppression of foxi3a
mRNA expression, while isotocin cRNA stimulated foxi3a mRNA expressions at the
tail-bud stage of zebrafish embryos. The density of P63 (an epidermal stem cell
marker)-positive cells was downregulated by isotocin morpholinos and was
upregulated by isotocin cRNA. Taken together, isotocin stimulates the
proliferation of epidermal stem cells and differentiation of ionocyte
progenitors by regulating the P63 and Foxi3a transcription factors, consequently
enhancing the functional activities of ionocytes. The nonapeptides arginine vasopressin (AVP; including its non-mammalian homolog
arginine vasotocin, AVT) and oxytocin (OT; including its non-mammalian homologs
mesotocin, MT, and isotocin, IT) regulate social behavior, including aggression
and reproduction, via receptors conserved across vertebrates. In monogamous
prairie voles, the vasopressin and oxytocin pathways are crucially important for
pair-bond formation, specifically by influencing affiliative behavior toward the
mate and aggression toward non-mates. Monogamous social systems are found in
diverse taxa. We hypothesized that the AVT/IT pathways are associated with
mating behavior in monogamous teleost fishes. We used the monogamous convict
cichlid, Amatitlania nigrofasciata, to test this idea. In the first experiment,
we treated males with a general nonapeptide receptor antagonist during pair-bond
formation. Control males were treated with vehicle. On the first day of
treatment we observed a significant reduction in both affiliative behavior
toward the potential mate and aggression toward neighbors. However, the
antagonist did not prevent the pair-bond from forming and the behavioral effects
disappeared on subsequent treatment days. In the second experiment, we
administered on three consecutive days the AVP/OT receptor antagonist to males
that were in an established pair-bond. In established pairs, male affiliation
towards the mate and aggressive behavior towards territorial neighbors were not
affected by the antagonist. Our results indicate that the basic social behaviors
typically mediated by the AVP/OT pathways may provide the building blocks
necessary for monogamous mating behavior. Oxytocin is a central neuromodulator required for facilitating mate preferences
for familiar individuals in a monogamous rodent (prairie vole), irrespective of
sex. While the role of oxytocin in mate choice is only understood in a few
monogamous species, its function in nonmonogamous species, comprising the vast
majority of vertebrate species, remains unclear. To address this issue, we
evaluated the involvement of an oxytocin homolog (isotocin, referred herein as
oxt) in mate choice in medaka fish (Oryzias latipes). Female medaka prefer to
choose familiar mates, whereas male medaka court indiscriminately, irrespective
of familiarity. We generated mutants of the oxt ligand (oxt) and receptor genes
(oxtr1 and oxtr2) and revealed that the oxt-oxtr1 signaling pathway was
essential for eliciting female mate preference for familiar males. This pathway
was also required for unrestricted and indiscriminate mating strategy in males.
That is, either oxt or oxtr1 mutation in males decreased the number of courtship
displays toward novel females, but not toward familiar females. Further, males
with these mutations exhibited enhanced mate-guarding behaviors toward familiar
females, but not toward novel females. In addition, RNA-sequencing (seq)
analysis revealed that the transcription of genes involved in gamma-amino
butyric acid metabolism as well as those encoding ion-transport ATPase are
up-regulated in both oxt and oxtr1 mutants only in female medaka, potentially
explaining the sex difference of the mutant phenotype. Our findings provide
genetic evidence that oxt-oxtr1 signaling plays a role in the mate choice for
familiar individuals in a sex-specific manner in medaka fish. Pro-social effects of oxytocin and its homologues are well-documented in birds
and mammals. However, in fishes, the effect of isotocin, the homologue of
oxytocin, on social behaviour is less clear. Studies in fishes have generally
shown no effect of isotocin on social behaviours or even an anti-social effect.
In our study, we measured association preference for conspecifics in 92 adult
guppies (46 females and 46 males), half of which were injected with isotocin and
the other half with an isotocin antagonist. We found that individuals injected
with isotocin spent 29% more time associating with conspecifics than individuals
injected with an isotocin antagonist. The effect of isotocin on association time
did not differ between males and females. Our study provides some of the first
evidence of a pro-social effects of isotocin in a fish and suggests that in
fishes, isotocin may have a homologous role to oxytocin, at least in promoting
shoaling behaviour. |
Fingolimod is a selective antagonist for which molecule? | Fingolimod is a selective S1P1 functional antagonist by induction of irreversible S1P1 internalization and degradation. | |
Does αCGRP have amyloidogenic properties? | Yes. αCGRP, a 37-residue-long peptide hormone, is a novel amyloidogenic member of the CGRP family | Author information:
(1)Section of Cell Biology and Biophysics, Department of Biology, School of
Sciences, National and Kapodistrian University of Athens, Panepistimiopolis,
Athens 157 01, Greece. Electronic address: [email protected].
(2)Section of Cell Biology and Biophysics, Department of Biology, School of
Sciences, National and Kapodistrian University of Athens, Panepistimiopolis,
Athens 157 01, Greece. Electronic address: [email protected].
(3)Section of Cell Biology and Biophysics, Department of Biology, School of
Sciences, National and Kapodistrian University of Athens, Panepistimiopolis,
Athens 157 01, Greece. Electronic address: [email protected].
(4)Section of Cell Biology and Biophysics, Department of Biology, School of
Sciences, National and Kapodistrian University of Athens, Panepistimiopolis,
Athens 157 01, Greece. Electronic address: [email protected].
(5)Department of Pharmacy, University of Patras, Patras 26504, Greece.
Electronic address: [email protected].
(6)Section of Cell Biology and Biophysics, Department of Biology, School of
Sciences, National and Kapodistrian University of Athens, Panepistimiopolis,
Athens 157 01, Greece. Electronic address: [email protected].
(7)Section of Cell Biology and Biophysics, Department of Biology, School of
Sciences, National and Kapodistrian University of Athens, Panepistimiopolis,
Athens 157 01, Greece. Electronic address: [email protected]. |