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1.
Development ; 148(19)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34486668

RESUMO

Birth defects result from interactions between genetic and environmental factors, but the mechanisms remain poorly understood. We find that mutations and teratogens interact in predictable ways to cause birth defects by changing target cell sensitivity to Hedgehog (Hh) ligands. These interactions converge on a membrane protein complex, the MMM complex, that promotes degradation of the Hh transducer Smoothened (SMO). Deficiency of the MMM component MOSMO results in elevated SMO and increased Hh signaling, causing multiple birth defects. In utero exposure to a teratogen that directly inhibits SMO reduces the penetrance and expressivity of birth defects in Mosmo-/- embryos. Additionally, tissues that develop normally in Mosmo-/- embryos are refractory to the teratogen. Thus, changes in the abundance of the protein target of a teratogen can change birth defect outcomes by quantitative shifts in Hh signaling. Consequently, small molecules that re-calibrate signaling strength could be harnessed to rescue structural birth defects.


Assuntos
Anormalidades Induzidas por Medicamentos/genética , Interação Gene-Ambiente , Proteínas Hedgehog/metabolismo , Penetrância , Animais , Células Cultivadas , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Transdução de Sinais , Receptor Smoothened/genética , Receptor Smoothened/metabolismo
2.
PLoS Genet ; 16(1): e1008558, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923184

RESUMO

Autophagy, particularly with BECN1, has paradoxically been highlighted as tumor promoting in Ras-driven cancers, but potentially tumor suppressing in breast and ovarian cancers. However, studying the specific role of BECN1 at the genetic level is complicated due to its genomic proximity to BRCA1 on both human (chromosome 17) and murine (chromosome 11) genomes. In human breast and ovarian cancers, the monoallelic deletion of these genes is often co-occurring. To investigate the potential tumor suppressor roles of two of the most commonly deleted autophagy genes in ovarian cancer, BECN1 and MAP1LC3B were knocked-down in atypical (BECN1+/+ and MAP1LC3B+/+) ovarian cancer cells. Ultra-performance liquid chromatography mass-spectrometry metabolomics revealed reduced levels of acetyl-CoA which corresponded with elevated levels of glycerophospholipids and sphingolipids. Migration rates of ovarian cancer cells were increased upon autophagy gene knockdown. Genomic instability was increased, resulting in copy-number alteration patterns which mimicked high grade serous ovarian cancer. We further investigated the causal role of Becn1 haploinsufficiency for oncogenesis in a MISIIR SV40 large T antigen driven spontaneous ovarian cancer mouse model. Tumors were evident earlier among the Becn1+/- mice, and this correlated with an increase in copy-number alterations per chromosome in the Becn1+/- tumors. The results support monoallelic loss of BECN1 as permissive for tumor initiation and potentiating for genomic instability in ovarian cancer.


Assuntos
Proteína Beclina-1/genética , Instabilidade Cromossômica , Haploinsuficiência , Proteínas Associadas aos Microtúbulos/genética , Neoplasias Ovarianas/genética , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular , Feminino , Metaboloma , Camundongos , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia
3.
J Hepatol ; 75(4): 820-828, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34023351

RESUMO

BACKGROUND & AIMS: Retreatment with glecaprevir/pibrentasvir (G/P) resulted in a rate of sustained virologic response 12 weeks after treatment completion (SVR12) of >90% in HCV genotype 1 (GT1) patients who previously failed a regimen of sofosbuvir plus an NS5A inhibitor (NS5Ai). This study investigated the prevalence and impact of baseline NS3 and NS5A resistance-associated substitutions (RASs) on the efficacy of G/P in prior GT1 sofosbuvir+NS5Ai failures and the persistence of treatment-emergent RASs. METHODS: Longitudinal samples from 177 patients enrolled in a phase IIIb, randomized pragmatic clinical trial were analyzed. Patients without cirrhosis were randomized to 12 or 16 weeks of G/P, and patients with compensated cirrhosis were randomized to G/P and ribavirin for 12 weeks or G/P for 16 weeks. Linkage of RAS was identified using Primer-ID next-generation sequencing at a 15% cut-off. RESULTS: Of 177 patients, 169 (95.5%) were PI-naïve. All 33 GT1b-infected patients achieved SVR12. In GT1a-infected patients, baseline NS5A RASs were prevalent (74.5%, 105/141) but NS3 RASs were uncommon. Baseline NS3 RASs had no impact on G/P efficacy and patients with baseline NS5A RASs showed a numerically but not statistically significantly lower SVR12 rate compared to those without NS5A RASs (89% vs. 97%). SVR12 was achieved in 34 of 35 (97%) patients without NS5A baseline substitution, and 53 of 57 (93%), 35 of 40 (88%), 5 of 8 (63%) with single, double-linked, and triple-linked NS5A substitutions, respectively. Among 13 patients with virologic failure, 4 acquired treatment-emergent NS3 RASs and 10 acquired NS5A RASs. CONCLUSION: Baseline NS5A RASs were highly prevalent. The presence of an increasing number of linked NS5A RASs in GT1a showed a trend in decreasing SVR12 rates, although no specific NS5A RASs or their linkage pattern were associated with lower SVR12 rates. LAY SUMMARY: Direct-acting antivirals have revolutionized the treatment of chronic hepatitis C infection, but treatment failure occurs in some patients. Retreatment of patients who previously failed a regimen consisting of sofosbuvir and an NS5A inhibitor with a regimen of glecaprevir and pibrentasvir (G/P) is >90% effective. Herein, we analyzed samples from these patients and showed that retreatment efficacy with G/P is lower in patients with double- or triple-linked NS5A resistance mutations than in patients with single or no NS5A resistance mutations. CLINICAL TRIAL NUMBER: NCT03092375.


Assuntos
Benzimidazóis/farmacologia , Resistência a Medicamentos/imunologia , Pirrolidinas/farmacologia , Quinoxalinas/farmacologia , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Sofosbuvir/metabolismo , Sulfonamidas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Adulto , Antivirais/administração & dosagem , Antivirais/metabolismo , Benzimidazóis/uso terapêutico , Combinação de Medicamentos , Feminino , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C/fisiopatologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pirrolidinas/uso terapêutico , Quinoxalinas/administração & dosagem , Quinoxalinas/uso terapêutico , RNA Polimerase Dependente de RNA/farmacologia , Sofosbuvir/administração & dosagem , Sulfonamidas/uso terapêutico , Estados Unidos/epidemiologia , Proteínas não Estruturais Virais/farmacologia
4.
Pain Physician ; 25(4): E531-E542, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35793177

RESUMO

BACKGROUND: Chronic pelvic pain (CPP) is a complex, heterogeneous condition affecting both female and male patients with significant effects on quality of life. Chronic pelvic pain is a prevalent but often underdiagnosed condition due to the variation in patient presentation, a gap in communication among specialties, under-reporting of the syndrome, and lack of standardized diagnostic criteria with a subsequent delay in diagnosis. The mechanism of CPP is complex due to multifactorial etiologies of pain and its vast anatomy and innervation. Potential causes of pelvic pain include the nerves, muscles, bone, or organs of the reproductive, gastrointestinal, urological, musculoskeletal, vascular, neurological, and psychological systems. OBJECTIVES: The objective of this article is to review the anatomy of the pelvis, share current lead placement locations, and discuss the current evidence for neuromodulation in the management of chronic pelvic pain. STUDY DESIGN: This is a narrative review of current literature on neuromodulation for chronic pelvic pain. SETTING: A database review. METHODS: A PubMed search was performed to gather literature on neuromodulation for chronic pelvic pain. RESULTS: Traditionally, pelvic pain has been managed with conservative therapies such as physical therapy, pharmacological agents, trigger point injections, botulinum toxin injections, ganglion impar blocks, caudal epidural steroid injections, or superior and inferior hypogastric blocks, but with the evolution of the neuromodulation, there are new advances to incorporate this modality in the management of chronic pelvic pain. LIMITATIONS: This review article possesses limitations and includes published data, excluding case reports. For this reason, some applications of neuromodulation for chronic pelvic pain may be missed. CONCLUSIONS: Neuromodulation may include spinal cord stimulation, dorsal root ganglion stimulation, and peripheral nerve stimulation. Specifically, neuromodulation utilizes electrical stimulation or pharmacological agents to modulate a nerve and alter pain signals. Currently used locations for lead placement include intracranial, spinal cord, dorsal root ganglion, sacral nerve roots, or at a peripheral nerve. As the field of pelvic pain continues to evolve, continued evidence for neuromodulatory interventions is needed.


Assuntos
Dor Crônica , Estimulação da Medula Espinal , Dor Crônica/terapia , Feminino , Gânglios Espinais , Humanos , Masculino , Dor Pélvica/terapia , Qualidade de Vida
5.
A A Pract ; 15(6): e01464, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34043601

RESUMO

An intrathecal drug delivery system (IDDS) has been widely utilized in the management of chronic pain and spasticity when oral pharmacologic agents are deemed ineffective. Typically, intrathecal pumps are implanted in the abdominal region; however, previous case reports have described nontraditional pump implantation sites, such as anterior thigh, gluteal region, and iliac fossa. Adding to the growing literature of alternative implantation sites, this case report discusses the implantation of the pump into the submuscular plane of the pectoralis major muscle and reviews the advantages and disadvantages of this location.


Assuntos
Bombas de Infusão Implantáveis , Músculos Peitorais , Humanos , Espasticidade Muscular , Músculos Peitorais/cirurgia
6.
Dev Cell ; 55(4): 432-449.e12, 2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-32966817

RESUMO

The etiology of congenital heart defects (CHDs), which are among the most common human birth defects, is poorly understood because of its complex genetic architecture. Here, we show that two genes implicated in CHDs, Megf8 and Mgrn1, interact genetically and biochemically to regulate the strength of Hedgehog signaling in target cells. MEGF8, a transmembrane protein, and MGRN1, a RING superfamily E3 ligase, assemble to form a receptor-like ubiquitin ligase complex that catalyzes the ubiquitination and degradation of the Hedgehog pathway transducer Smoothened. Homozygous Megf8 and Mgrn1 mutations increased Smoothened abundance and elevated sensitivity to Hedgehog ligands. While mice heterozygous for loss-of-function Megf8 or Mgrn1 mutations were normal, double heterozygous embryos exhibited an incompletely penetrant syndrome of CHDs with heterotaxy. Thus, genetic interactions can arise from biochemical mechanisms that calibrate morphogen signaling strength, a conclusion broadly relevant for the many human diseases in which oligogenic inheritance is emerging as a mechanism for heritability.


Assuntos
Coração/embriologia , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Ubiquitinação , Alelos , Animais , Embrião de Mamíferos/metabolismo , Epistasia Genética , Dosagem de Genes , Proteínas de Membrana/metabolismo , Camundongos , Mutação/genética , Células NIH 3T3 , Fenótipo , Ligação Proteica , Receptor Smoothened/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
7.
Nat Commun ; 8: 14423, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28198375

RESUMO

Identification of specific oncogenic gene changes has enabled the modern generation of targeted cancer therapeutics. In high-grade serous ovarian cancer (OV), the bulk of genetic changes is not somatic point mutations, but rather somatic copy-number alterations (SCNAs). The impact of SCNAs on tumour biology remains poorly understood. Here we build haploinsufficiency network analyses to identify which SCNA patterns are most disruptive in OV. Of all KEGG pathways (N=187), autophagy is the most significantly disrupted by coincident gene deletions. Compared with 20 other cancer types, OV is most severely disrupted in autophagy and in compensatory proteostasis pathways. Network analysis prioritizes MAP1LC3B (LC3) and BECN1 as most impactful. Knockdown of LC3 and BECN1 expression confers sensitivity to cells undergoing autophagic stress independent of platinum resistance status. The results support the use of pathway network tools to evaluate how the copy-number landscape of a tumour may guide therapy.


Assuntos
Alelos , Haploinsuficiência/genética , Mutação/genética , Neoplasias Ovarianas/genética , Autofagia/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Variações do Número de Cópias de DNA/genética , Sistemas de Liberação de Medicamentos , Feminino , Genes Neoplásicos , Humanos , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Proteostase/genética
8.
Drug Des Devel Ther ; 10: 1837-46, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27330277

RESUMO

OBJECTIVE: The standard treatment for cervical cancer in developed countries includes surgery and chemoradiation, with standard of care lagging in developing countries. Even in the former case, treatment frequently yields recalcitrant tumors and women succumb to disease. Here we examine the impact of nelfinavir, an off-patent viral protease inhibitor, which has shown promise as an antineoplastic agent. METHODS: We evaluated the morphological and proliferative effects of the autophagy-stressing drug nelfinavir in normal and cisplatin-resistant cervical cancer cells. Immunofluorescent validation of autophagy markers was performed and the impact of nelfinavir in an in vivo model of tumor growth was determined. RESULTS: Nelfinavir exhibits cytotoxicity against both cisplatin-sensitive and -resistant ME-180 human cervical cancer cells in vitro and in vivo. Immunoblotting and immunofluorescence showed an expression of the autophagy marker LC3-II in response to nelfinavir treatment. CONCLUSION: Nelfinavir, now available as an inexpensive generic orally dosed agent (Nelvir), is cytotoxic against cervical cancer cells. It acts by burdening the autophagy pathway to impair tumor cell survival and a modest induction of apoptosis. While further studies are needed to elucidate the optimal method of application of nelfinavir, it may represent an appealing global option for the treatment of cervical cancer.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Cisplatino/farmacologia , Nelfinavir/farmacologia , Neoplasias do Colo do Útero/patologia , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Cisplatino/química , Feminino , Humanos , Nelfinavir/química
9.
3 Biotech ; 5(6): 933-938, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28324392

RESUMO

Cross-species transferability and expressed sequence tags (ESTs) in public databases are cost-effective means for developing simple sequence repeats (SSRs) for less-studied species like medicinal plants. In this study, 11 EST-SSR markers developed from 742 available ESTs of Withania Somnifera EST sequences and 95 SSR primer pairs derived from other solanaceous crops (tomato, eggplant, chili, and tobacco) were utilized for their amplification and validation. Out of 11, 10 EST-SSRs showed good amplification quality and produced 13 loci with a product size ranging between 167 and 291 bp. Similarly, of the 95 cross-genera SSR loci assayed, 20 (21 %) markers showed the transferability of 5, 27, 32, and 14.2 % from eggplant, chili, tomato, and tobacco, respectively, to ashwagandha. In toto, these 30 SSR markers reported here will be valuable resources and may be applicable for the analysis of intra- and inter-specific genetic diversity in ashwagandha for which till date no information about SSR is available.

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