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1.
Cell ; 180(4): 688-702.e13, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32084340

RESUMO

Due to the rapid emergence of antibiotic-resistant bacteria, there is a growing need to discover new antibiotics. To address this challenge, we trained a deep neural network capable of predicting molecules with antibacterial activity. We performed predictions on multiple chemical libraries and discovered a molecule from the Drug Repurposing Hub-halicin-that is structurally divergent from conventional antibiotics and displays bactericidal activity against a wide phylogenetic spectrum of pathogens including Mycobacterium tuberculosis and carbapenem-resistant Enterobacteriaceae. Halicin also effectively treated Clostridioides difficile and pan-resistant Acinetobacter baumannii infections in murine models. Additionally, from a discrete set of 23 empirically tested predictions from >107 million molecules curated from the ZINC15 database, our model identified eight antibacterial compounds that are structurally distant from known antibiotics. This work highlights the utility of deep learning approaches to expand our antibiotic arsenal through the discovery of structurally distinct antibacterial molecules.


Assuntos
Antibacterianos/farmacologia , Descoberta de Drogas/métodos , Aprendizado de Máquina , Tiadiazóis/farmacologia , Acinetobacter baumannii/efeitos dos fármacos , Animais , Antibacterianos/química , Quimioinformática/métodos , Clostridioides difficile/efeitos dos fármacos , Bases de Dados de Compostos Químicos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Tiadiazóis/química
2.
Cell ; 174(6): 1436-1449.e20, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30146163

RESUMO

Synaptic vesicle and active zone proteins are required for synaptogenesis. The molecular mechanisms for coordinated synthesis of these proteins are not understood. Using forward genetic screens, we identified the conserved THO nuclear export complex (THOC) as an important regulator of presynapse development in C. elegans dopaminergic neurons. In THOC mutants, synaptic messenger RNAs are retained in the nucleus, resulting in dramatic decrease of synaptic protein expression, near complete loss of synapses, and compromised dopamine function. CRE binding protein (CREB) interacts with THOC to mark synaptic transcripts for efficient nuclear export. Deletion of Thoc5, a THOC subunit, in mouse dopaminergic neurons causes severe defects in synapse maintenance and subsequent neuronal death in the substantia nigra compacta. These cellular defects lead to abrogated dopamine release, ataxia, and animal death. Together, our results argue that nuclear export mechanisms can select specific mRNAs and be a rate-limiting step for neuronal differentiation and survival.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Neurônios Dopaminérgicos/metabolismo , Proteínas Nucleares/genética , Sinapses/metabolismo , Transporte Ativo do Núcleo Celular , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/metabolismo , Sinalização do Cálcio , Núcleo Celular/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutagênese , Mutação de Sentido Incorreto , Proteínas Nucleares/deficiência , Proteínas Nucleares/metabolismo , Subunidades Proteicas/deficiência , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo
3.
Mol Cell ; 84(5): 897-909.e4, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38340716

RESUMO

RNA polymerase II (RNA Pol II) can backtrack during transcription elongation, exposing the 3' end of nascent RNA. Nascent RNA sequencing can approximate the location of backtracking events that are quickly resolved; however, the extent and genome-wide distribution of more persistent backtracking are unknown. Consequently, we developed a method to directly sequence the extruded, "backtracked" 3' RNA. Our data show that RNA Pol II slides backward more than 20 nt in human cells and can persist in this backtracked state. Persistent backtracking mainly occurs where RNA Pol II pauses near promoters and intron-exon junctions and is enriched in genes involved in translation, replication, and development, where gene expression is decreased if these events are unresolved. Histone genes are highly prone to persistent backtracking, and the resolution of such events is likely required for timely expression during cell division. These results demonstrate that persistent backtracking can potentially affect diverse gene expression programs.


Assuntos
RNA Polimerase II , RNA , Humanos , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , RNA/genética , Transcrição Gênica , RNA Polimerases Dirigidas por DNA/genética
5.
Nature ; 622(7981): 180-187, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37648864

RESUMO

Antibiotic binding sites are located in important domains of essential enzymes and have been extensively studied in the context of resistance mutations; however, their study is limited by positive selection. Using multiplex genome engineering1 to overcome this constraint, we generate and characterize a collection of 760 single-residue mutants encompassing the entire rifampicin binding site of Escherichia coli RNA polymerase (RNAP). By genetically mapping drug-enzyme interactions, we identify an alpha helix where mutations considerably enhance or disrupt rifampicin binding. We find mutations in this region that prolong antibiotic binding, converting rifampicin from a bacteriostatic to bactericidal drug by inducing lethal DNA breaks. The latter are replication dependent, indicating that rifampicin kills by causing detrimental transcription-replication conflicts at promoters. We also identify additional binding site mutations that greatly increase the speed of RNAP.Fast RNAP depletes the cell of nucleotides, alters cell sensitivity to different antibiotics and provides a cold growth advantage. Finally, by mapping natural rpoB sequence diversity, we discover that functional rifampicin binding site mutations that alter RNAP properties or confer drug resistance occur frequently in nature.


Assuntos
Antibacterianos , Sítios de Ligação , RNA Polimerases Dirigidas por DNA , Escherichia coli , Mutação , Rifampina , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/genética , Quebras de DNA/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Nucleotídeos/deficiência , Nucleotídeos/metabolismo , Regiões Promotoras Genéticas , Rifampina/química , Rifampina/metabolismo , Rifampina/farmacologia , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos
6.
PLoS Pathog ; 18(1): e1010236, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35041709

RESUMO

While traditional methods for studying large DNA viruses allow the creation of individual mutants, CRISPR/Cas9 can be used to rapidly create thousands of mutant dsDNA viruses in parallel, enabling the pooled screening of entire viral genomes. Here, we applied this approach to Kaposi's sarcoma-associated herpesvirus (KSHV) by designing a sgRNA library containing all possible ~22,000 guides targeting the 154 kilobase viral genome, corresponding to one cut site approximately every 8 base pairs. We used the library to profile viral sequences involved in transcriptional activation of late genes, whose regulation involves several well characterized features including dependence on viral DNA replication and a known set of viral transcriptional activators. Upon phenotyping all possible Cas9-targeted viruses for transcription of KSHV late genes we recovered these established regulators and identified a new required factor (ORF46), highlighting the utility of the screening pipeline. By performing targeted deep sequencing of the viral genome to distinguish between knock-out and in-frame alleles created by Cas9, we identify the DNA binding but not catalytic domain of ORF46 to be required for viral DNA replication and thus late gene expression. Our pooled Cas9 tiling screen followed by targeted deep viral sequencing represents a two-tiered screening paradigm that may be widely applicable to dsDNA viruses.


Assuntos
Regulação Viral da Expressão Gênica/fisiologia , Genes Virais/genética , Herpesvirus Humano 8/genética , Sistemas CRISPR-Cas , Células HEK293 , Humanos
7.
Gynecol Oncol ; 187: 12-20, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38703673

RESUMO

OBJECTIVES: Uterine carcinosarcomas (UCS) are rare, biologically aggressive tumors. Since UCS may harbor mutations in RAS/MAPK pathway genes we evaluated the preclinical in vitro and in vivo efficacy of the RAF/MEK clamp avutometinib in combination with the focal adhesion kinase (FAK) inhibitors defactinib or VS-4718 against multiple primary UCS cell lines and xenografts. METHODS: Whole-exome-sequencing (WES) was used to evaluate the genetic landscape of 5 primary UCS cell lines. The in vitro activity of avutometinib ± FAK inhibitor was evaluated using cell viability and cell cycle assays against primary UCS cell lines. Mechanistic studies were performed using western blot assays while in vivo experiments were completed in UCS tumor bearing mice treated with avutometinib ± FAK inhibitor by oral gavage. RESULTS: WES results demonstrated multiple UCS cell lines harbor genetic alterations including KRAS, PTK2, BRAF, MAP2K, and MAP2K1, potentially sensitizing to FAK and RAF/MEK inhibition. Four out of five of the UCS cell lines demonstrated in vitro sensitivity to FAK and/or RAF/MEK inhibition when used alone or in combination. By western blot assays, exposure of UCS cell lines to the combination of defactinib/avutometinib demonstrated decreased phosphorylated (p)-FAK as well as decreased p-ERK. In vivo, the combination of avutometinib/VS-4718 demonstrated superior tumor growth inhibition and longer survival compared to single agent treatment and controls starting at day 10 (p < 0.002) in UCS xenografts. CONCLUSION: The combination of avutometinib and defactinib demonstrates promising in vitro and in vivo anti-tumor activity against primary UCS cell lines and xenografts.


Assuntos
Carcinossarcoma , Neoplasias Uterinas , Ensaios Antitumorais Modelo de Xenoenxerto , Feminino , Humanos , Animais , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/patologia , Neoplasias Uterinas/genética , Neoplasias Uterinas/metabolismo , Linhagem Celular Tumoral , Camundongos , Carcinossarcoma/tratamento farmacológico , Carcinossarcoma/patologia , Carcinossarcoma/genética , Carcinossarcoma/metabolismo , Quinase 1 de Adesão Focal/antagonistas & inibidores , Quinase 1 de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/genética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Indóis/farmacologia , Quinases raf/antagonistas & inibidores , Quinases raf/metabolismo , Quinases raf/genética , Sequenciamento do Exoma , Camundongos Nus , Benzamidas , Pirazinas , Sulfonamidas
8.
Gynecol Oncol ; 183: 133-140, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38493021

RESUMO

OBJECTIVES: Low-grade-serous-ovarian-carcinoma (LGSOC) is characterized by a high recurrence rate and limited therapeutic options. About one-third of LGSOC contains mutations in MAPK pathway genes such as KRAS/NRAS/BRAF. Avutometinib is a dual RAF/MEK inhibitor while defactinib and VS-4718 are focal-adhesion-kinase-inhibitors (FAKi). We determined the preclinical efficacy of avutometinib±VS-4718 in LGSOC patient-derived-tumor-xenografts (PDX). METHODS: Whole-exome-sequencing (WES) was used to evaluate the genetic fingerprint of 3 patient-derived LGSOC (OVA(K)250, PERIT(M)17 and A(PE)148). OVA(K)250 tissue was successfully xenografted as PDX into female CB17/lcrHsd-Prkdc/SCID-mice. Animals were treated with either control, avutometinib, VS-4718, or avutometinib/ VS-4718 once daily five days on and two days off through oral gavage. Mechanistic studies were performed ex vivo using avutometinib±defactinib treated LGSOC tumor samples by western blot. RESULTS: WES results demonstrated wild-type KRAS in all 3 LGSOC. OVA(K)250 PDX showed gain-of-function mutations (GOF) in PTK2 and PTK2B genes, and loss-of-heterozygosity in ADRB2, potentially sensitizing to FAK and RAF/MEK inhibition. The combination of avutometinib/ VS-4718 demonstrated strong tumor-growth inhibition compared to controls starting at day 9 (p < 0.002) in OVA(K)250PDX. By 60 days, mice treated with avutometinib alone and avutometinib/VS-4718 were still alive; compared to median survival of 20 days in control-treated mice and of 35 days in VS-4718-treated mice (p < 0.0001). By western-blot assays exposure of OVA(K)250 to avutometinib, FAKi defactinib and their combination demonstrated decreased phosphorylated FAK (p-FAK) as well as decreased p-ERK. CONCLUSION: Avutometinib, and to a larger extent its combination with FAK inhibitor VS-4718, demonstrated promising in vivo activity against a KRAS wild-type LGSOC-PDX. These data support the ongoing registration-directed study (RAMP201/NCT04625270).


Assuntos
Quinase 1 de Adesão Focal , Neoplasias Ovarianas , Ensaios Antitumorais Modelo de Xenoenxerto , Feminino , Humanos , Animais , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Camundongos , Quinase 1 de Adesão Focal/antagonistas & inibidores , Quinase 1 de Adesão Focal/genética , Quinase 1 de Adesão Focal/metabolismo , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/patologia , Cistadenocarcinoma Seroso/genética , Inibidores de Proteínas Quinases/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Sequenciamento do Exoma , Benzamidas , Difenilamina/análogos & derivados , Pirazinas , Sulfonamidas
9.
PLoS Comput Biol ; 19(5): e1011162, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37220151

RESUMO

Natural products are chemical compounds that form the basis of many therapeutics used in the pharmaceutical industry. In microbes, natural products are synthesized by groups of colocalized genes called biosynthetic gene clusters (BGCs). With advances in high-throughput sequencing, there has been an increase of complete microbial isolate genomes and metagenomes, from which a vast number of BGCs are undiscovered. Here, we introduce a self-supervised learning approach designed to identify and characterize BGCs from such data. To do this, we represent BGCs as chains of functional protein domains and train a masked language model on these domains. We assess the ability of our approach to detect BGCs and characterize BGC properties in bacterial genomes. We also demonstrate that our model can learn meaningful representations of BGCs and their constituent domains, detect BGCs in microbial genomes, and predict BGC product classes. These results highlight self-supervised neural networks as a promising framework for improving BGC prediction and classification.


Assuntos
Produtos Biológicos , Genoma Bacteriano , Metagenoma , Família Multigênica/genética , Produtos Biológicos/metabolismo , Aprendizado de Máquina Supervisionado
10.
J Craniofac Surg ; 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39453769

RESUMO

Late secondary reconstruction is sometimes required in patients with suboptimal primary panfacial fracture repair. At this stage, it can be difficult to discern original facial architecture due to malunion and bony remodeling. By utilizing the original postinjury CT scan to complete fracture reduction in the virtual reality (VR) planning environment, the surgeon may attempt to recreate an "ideal" facial bony anatomy for patients. This technique was completed in 2 patients presenting with facial deformity secondary to malunited panfacial fracture. Each had a cone-beam CT (CBCT) scan taken at presentation and the initial postinjury CT scans were obtained. Fracture reductions were completed in VR to recreate the preinjury anatomy. The resulting model was overlaid with current anatomy to create surgical aids. The first patient, a 23-year-old man, presented with malunion of all bones of the midface. Cutting guides were designed for the Lefort 1 segment, left zygomaticomaxillary complex (ZMC), and naso-orbito-ethmoid (NOE) osteotomies. The second patient, a 30-year-old woman, had bilateral ZMC and subcondylar fractures, midface retrusion, and malunion of parasymphyseal fracture. A 2-stage procedure was planned, including an initial Lefort I and bilateral sagittal split osteotomy with midline wedge excision. To address malar projection, a second surgery was planned using custom MEDPOR midface implants for the NOE and zygomatic regions. Both patients were discharged home, and all surgical goals and esthetic objectives were achieved.

11.
J Clin Nurs ; 33(3): 1062-1075, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37828851

RESUMO

BACKGROUND: Malnutrition, sedentary lifestyle, cognitive dysfunction and poor psychological well-being are often reported in patients on haemodialysis (HD). AIMS: We aimed to explore needs, barriers and facilitators-as perceived by patients, their carers, and healthcare professionals (HCPs) for increasing the adherence to the diet, to physical activity and cognition and psychological well-being. METHODS: This is an observational cross-sectional study following the STROBE statement. This study is part of an ERASMUS+ project, GoodRENal-aiming to develop digital tools as an educational approach to patients on HD. For that, the GoodRENal comprises HD centers located in four Belgium, Greece, Spain and Sweden. Exploratory questionnaires were developed regarding the perceived needs, barriers and facilitators regarding the diet, physical activity, cognition and psychological well-being from the perspective of patients, their carers and HCPs. RESULTS: In total, 38 patients, 34 carers and 38 HCPs were included. Nutrition: For patients and carers, the main needs to adhere to the diet included learning more about nutrients and minerals. For patients, the main barrier was not being able to eat what they like. Physical activity: As needs it was reported information about type of appropriate physical activity, while fatigue was listed as the main barrier. For Cognitive and emotional state, it was perceived as positive for patients and carers perception but not for HCPs. The HCPs identified as needs working as a team, having access to specialised HCP and being able to talk to patients in private. CONCLUSIONS: Patients and their carers listed as needs guidance regarding nutrition and physical activity but were positive with their cognitive and emotional state. The HCPs corroborated these needs and emphasised the importance of teamwork and expert support.


Assuntos
Cuidadores , Pessoal de Saúde , Humanos , Estudos Transversais , Pessoal de Saúde/psicologia , Cuidadores/psicologia , Emoções , Estilo de Vida Saudável
12.
Curr Opin Anaesthesiol ; 37(5): 439-445, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39011661

RESUMO

PURPOSE OF REVIEW: The anesthetic management of patients with Moyamoya disease (MMD) is challenging and continues to evolve. The goal of this review is to provide updated recommendations on the anesthetic management of adult MMD patients based on the relevant existing literature. RECENT FINDINGS: Key findings include the importance of aggressive hydration preoperatively to sustain cerebral perfusion. Hypertension induced intraoperatively may prevent cerebral hypoperfusion. Vigilance against cerebral hyperperfusion after revascularization is necessary, with specific blood pressure targets recommended. Fluid management should aim for normovolemia to mild hypervolemia. Maintaining body temperature helps prevent cerebral vasospasm induced by hypothermia. Maintaining adequate oxygen supply during surgery is crucial. In cases of ischemic stroke, managing hematocrit and oxygen carrying capacity is essential to prevent further ischemia. Extubation decisions should consider baseline neurological function, while postoperative normocapnia helps prevent cerebral hyperperfusion and hypertension. In intensive care, cautious blood pressure management is crucial to prevent secondary complications. SUMMARY: Strategies in the preoperative, intraoperative, and postoperative anesthetic management of MMD patients should aim to maintain adequate cerebral perfusion to prevent cerebral ischemia.


Assuntos
Anestesia , Doença de Moyamoya , Humanos , Doença de Moyamoya/cirurgia , Anestesia/métodos , Anestesia/efeitos adversos , Adulto , Circulação Cerebrovascular , Isquemia Encefálica/prevenção & controle , Isquemia Encefálica/etiologia
13.
Mol Biol Evol ; 39(5)2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35535514

RESUMO

Highly diversified astigmatic mites comprise many medically important human household pests such as house dust mites causing ∼1-2% of all allergic diseases globally; however, their evolutionary origin and diverse lifestyles including reversible parasitism have not been illustrated at the genomic level, which hampers allergy prevention and our exploration of these household pests. Using six high-quality assembled and annotated genomes, this study not only refuted the monophyly of mites and ticks, but also thoroughly explored the divergence of Acariformes and the diversification of astigmatic mites. In monophyletic Acariformes, Prostigmata known as notorious plant pests first evolved, and then rapidly evolving Astigmata diverged from soil oribatid mites. Within astigmatic mites, a wide range of gene families rapidly expanded via tandem gene duplications, including ionotropic glutamate receptors, triacylglycerol lipases, serine proteases and UDP glucuronosyltransferases. Gene diversification after tandem duplications provides many genetic resources for adaptation to sensing environmental signals, digestion, and detoxification in rapidly changing household environments. Many gene decay events only occurred in the skin-burrowing parasitic mite Sarcoptes scabiei. Throughout the evolution of Acariformes, massive horizontal gene transfer events occurred in gene families such as UDP glucuronosyltransferases and several important fungal cell wall lytic enzymes, which enable detoxification and digestive functions and provide perfect drug targets for pest control. This comparative study sheds light on the divergent evolution and quick adaptation to human household environments of astigmatic mites and provides insights into the genetic adaptations and even control of human household pests.


Assuntos
Adaptação Fisiológica , Genômica , Adaptação Fisiológica/genética , Genoma , Humanos , Difosfato de Uridina
14.
Sex Transm Dis ; 50(3): 131-137, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729626

RESUMO

BACKGROUND: To treat Neisseria gonorrhoeae infection, the Centers for Disease Control and Prevention recommends a single oral dose of cefixime as an alternative to injectable ceftriaxone. METHODS: We conducted a systematic review and meta-analysis to describe the effectiveness of cefixime in treating N. gonorrhoeae infection at 3 different anatomic sites.We searched PubMed and Embase database to abstract treatment success rates and cefixime dosage/frequency for studies that reported the anatomical site of infection. We included reports published between January 1, 1980, and December 7, 2021. Twenty studies published between 1989 and 2015 were included in our meta-analysis. We calculated pooled treatment success percentages and 95% confidence intervals (CIs) using random-effects models. RESULTS: Of patients who received a 400-mg single dose of cefixime, 824 of 846 (97%; 95% CI, 96%-98%) patients with urogenital infection, 107 of 112 (97%; 95% CI, 84%-100%) patients with rectal infection, and 202 of 242 (89%; 95% CI, 76%-96%) patients with pharyngeal infection were cured. Of patients who received an 800-mg single dose of cefixime, 295 of 301 (98%; 95% CI, 96%-99%) patients with urogenital infection and 21 of 26 (81%; 95% CI, 61%-92%) patients with pharyngeal infection were cured. CONCLUSIONS: Our meta-analysis found that cefixime is highly effective at treating urogenital infections and less effective at treating pharyngeal infections. We recommend more investigation into the effectiveness of cefixime in treating rectal infections and studying multidose therapy for the cefixime treatment of pharyngeal infection.


Assuntos
Gonorreia , Humanos , Cefixima/farmacologia , Gonorreia/tratamento farmacológico , Antibacterianos/farmacologia , Ceftriaxona/uso terapêutico , Resultado do Tratamento , Neisseria gonorrhoeae , Testes de Sensibilidade Microbiana
15.
Gynecol Oncol ; 172: 65-71, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36958197

RESUMO

INTRODUCTION: Uterine leiomyosarcomas (uLMS) are rare, highly aggressive tumors. Up to 30% of uLMS may harbor gain of function (GOF) in the MAP2K4 gene, important for tumor cell proliferation, differentiation and metastasis. We investigated the in vivo activity of a novel MAP2K4 inhibitor, PLX8725, against uLMS harboring MAP2K4 gene-amplification. METHODS: Two fully characterized uLMS (i.e., LEY-11 and LEY-16) were grafted into female CB-17/SCID mice. Treatments with control vehicle or PLX8725 (50 mg/kg) were given via oral gavage daily on weekdays for up to 60 days. Tumor volume differences were calculated with two-way ANOVA. Pharmacokinetic (PK) and mechanistic studies of PLX8725 in uLMS PDX models were also performed. RESULTS: Both uLMS tumors evaluated demonstrated GOF in MAP2K4 (i.e., 3 CNV in both LEY-11 and LEY-16). Tumor growth inhibition was significantly greater in both PDX LEY-11 and PDX LEY-16 treated with PLX8725 when compared to controls (p < 0.001). Median overall survival was also significantly longer in both PDX LEY-11 (p = 0.0047) and PDX LEY-16 (p = 0.0058) treatment cohorts when compared to controls. PLX8725 oral treatment was well tolerated, and PK studies demonstrated that oral PLX8725 gives extended exposure in mice. Ex vivo tumor samples after PLX8725 exposure decreased phosphorylated-ATR, JNK and p38, and increased expression of apoptotic molecules on western blot. CONCLUSION: PLX8725 demonstrates promising in vivo activity against PDX models of uLMS harboring GOF alterations in the MAP2K4 gene with tolerable toxicity. Phase I trials of PLX8725 in advanced, recurrent, chemotherapy-resistant uLMS patients are warranted.


Assuntos
Leiomiossarcoma , Neoplasias Pélvicas , Neoplasias Uterinas , Humanos , Feminino , Animais , Camundongos , Leiomiossarcoma/tratamento farmacológico , Leiomiossarcoma/genética , Leiomiossarcoma/patologia , Amplificação de Genes , Camundongos SCID , Recidiva Local de Neoplasia/genética , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia , MAP Quinase Quinase 4/genética
16.
PLoS Comput Biol ; 18(2): e1009853, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35143485

RESUMO

Biocatalysis is a promising approach to sustainably synthesize pharmaceuticals, complex natural products, and commodity chemicals at scale. However, the adoption of biocatalysis is limited by our ability to select enzymes that will catalyze their natural chemical transformation on non-natural substrates. While machine learning and in silico directed evolution are well-posed for this predictive modeling challenge, efforts to date have primarily aimed to increase activity against a single known substrate, rather than to identify enzymes capable of acting on new substrates of interest. To address this need, we curate 6 different high-quality enzyme family screens from the literature that each measure multiple enzymes against multiple substrates. We compare machine learning-based compound-protein interaction (CPI) modeling approaches from the literature used for predicting drug-target interactions. Surprisingly, comparing these interaction-based models against collections of independent (single task) enzyme-only or substrate-only models reveals that current CPI approaches are incapable of learning interactions between compounds and proteins in the current family level data regime. We further validate this observation by demonstrating that our no-interaction baseline can outperform CPI-based models from the literature used to guide the discovery of kinase inhibitors. Given the high performance of non-interaction based models, we introduce a new structure-based strategy for pooling residue representations across a protein sequence. Altogether, this work motivates a principled path forward in order to build and evaluate meaningful predictive models for biocatalysis and other drug discovery applications.


Assuntos
Aprendizado de Máquina , Proteínas , Sequência de Aminoácidos , Descoberta de Drogas , Proteínas/química , Especificidade por Substrato
17.
PLoS Comput Biol ; 18(5): e1010045, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35500014

RESUMO

Identifying structural differences among proteins can be a non-trivial task. When contrasting ensembles of protein structures obtained from molecular dynamics simulations, biologically-relevant features can be easily overshadowed by spurious fluctuations. Here, we present SINATRA Pro, a computational pipeline designed to robustly identify topological differences between two sets of protein structures. Algorithmically, SINATRA Pro works by first taking in the 3D atomic coordinates for each protein snapshot and summarizing them according to their underlying topology. Statistically significant topological features are then projected back onto a user-selected representative protein structure, thus facilitating the visual identification of biophysical signatures of different protein ensembles. We assess the ability of SINATRA Pro to detect minute conformational changes in five independent protein systems of varying complexities. In all test cases, SINATRA Pro identifies known structural features that have been validated by previous experimental and computational studies, as well as novel features that are also likely to be biologically-relevant according to the literature. These results highlight SINATRA Pro as a promising method for facilitating the non-trivial task of pattern recognition in trajectories resulting from molecular dynamics simulations, with substantially increased resolution.


Assuntos
Ciência de Dados , Simulação de Dinâmica Molecular , Biofísica , Conformação Proteica , Proteínas/química
18.
Prev Med ; 177: 107768, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37951542

RESUMO

INTRODUCTION: While there is increasing interest in the use of cannabis to manage a range of health-related symptoms, little is known about trends in recent cannabis use with respect to various health conditions. METHODS: We examined data from a US representative sample of noninstitutionalized adults age ≥ 18 from the 2015-2019 National Survey on Drug Use and Health (N = 214,505). We estimated the pooled prevalences followed by linear time trends, overall, and by disability (i.e., difficulty hearing, seeing, thinking, walking, dressing, doing errands) and lifetime (i.e., bronchitis, cancer, diabetes, hepatitis, kidney disease) and current (i.e., asthma, depression, heart disease, hypertension) health condition status using logistic regression. Models with year-by-condition status interaction terms were used to assess differential time trends, adjusting for demographic characteristics. RESULTS: From 2015 to 2019, cannabis use increased significantly among adults with and without each disability and health condition examined. However, the increase was more rapid among those with (versus without) difficulty hearing (89.8% increase [4.9% to 9.3%] vs. 37.9% increase [8.7% to 12.0%], p = 0.015), difficulty walking (84.1% increase [6.3% to 11.6%] vs. 36.8% increase [8.7% to 11.9%], p < 0.001), 2-3 impairments (75.3% increase [9.3% to 16.3%] vs. 36.6% increase [8.2% to 11.2%], p = 0.041), and kidney disease (135.3% increase [3.4% to 8.0%] vs. 38.4% increase [8.6% to 11.9%], p = 0.045). CONCLUSION: Given the potential adverse effects of cannabis, prevention and harm reduction efforts should focus on groups at increasingly higher risk for use, including those with disabilities and kidney disease.


Assuntos
Cannabis , Pessoas com Deficiência , Nefropatias , Abuso de Maconha , Adulto , Humanos , Abuso de Maconha/epidemiologia , Prevalência
19.
Bioorg Med Chem ; 80: 117173, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36696874

RESUMO

We combined a mechanism-informed phenotypic screening (MIPS) assay with a structural simplification strategy to guide the discovery of compounds that disrupt the localization of the mitotic regulator, Aurora kinase B (AURKB), rather than inhibiting its catalytic activity. An initial hit 4-(4-methylthiophen-2-yl)-N-(4-(quinolin-4-yloxy)phenyl)phthalazin-1-amine was identified after screening an in-house library of small molecules and phenocopied the loss of function mutations in AURKB without inhibiting its catalytic activity. We isolated this hit compound activity to its 4-phenoxy-quinoline moiety. The fragment was further optimized into a class of new chemical entities that potently disrupt the mitotic localization of AURKB at low nanomolar concentrations and consequently elicit severe growth inhibition in diverse human cancer cell lines. A lead compound, N-(3-methoxy-5-(6-methoxyquinolin-4-yl)oxy)phenyl)acetamide possessed desirable pharmacokinetic properties such as AUC0-∞: 227.15 [ng∙h/mL/(mg/kg)]; Cmax: 3378.52 ng/mL T1/2: 3.52 h; and F%: 42 % and produced the AURKB-inhibitory phenotypes in a mouse xenograft model. A lead compound is a powerful tool for interrogating the regulation of AURKB and has the potential to be further developed as a first-in-class oncology therapeutic.


Assuntos
Neoplasias , Quinolinas , Humanos , Camundongos , Animais , Aurora Quinase B , Fenótipo , Aurora Quinase A/metabolismo
20.
Surg Endosc ; 37(7): 5052-5064, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37308760

RESUMO

BACKGROUND: In the surgical management of GERD, the traditional procedure is laparoscopic total (Nissen) fundoplication. However, partial fundoplication has been advocated as providing similar reflux control while potentially minimizing dysphagia. The comparative outcomes of different approaches to fundoplication are a topic of ongoing debate and long-term outcomes remain uncertain. This study aims to compare long-term gastroesophageal reflux disease (GERD) related outcomes following different fundoplication procedures. METHODS: MEDLINE, EMBASE, PubMed, and CENTRAL databases were searched up to November 2022 to identify randomized controlled trials (RCTs) comparing different types of fundoplications reporting long-term (> 5 years) outcomes. The primary outcome was incidence of dysphagia. Secondary outcomes included incidence of heartburn/reflux, regurgitation, inability to belch, abdominal bloating, reoperation, and patient satisfaction. DataParty, which uses Python 3.8.10 was used to perform the network meta-analysis. We evaluated the overall certainty of evidence with the GRADE framework. RESULTS: 13 RCTs were included, with 2063 patients across Nissen (360°), Dor (anterior 180°-200°), and Toupet (posterior 270°) fundoplications. Network estimates demonstrated that Toupet had lower incidence of dysphagia compared to Nissen (OR 0.285; 95% CrI 0.06-0.958). There were no differences in dysphagia between Toupet and Dor (OR 0.473, 95% CrI 0.072-2.835) or between Dor and Nissen (OR 1.689, 95% CrI 0.403-7.699). The three fundoplication types were comparable in all other outcomes. CONCLUSIONS: All three approaches of fundoplication share similar long-term outcomes, with the Toupet fundoplication likely providing the best long-term durability with lowest odds of developing postoperative dysphagia.


Assuntos
Transtornos de Deglutição , Refluxo Gastroesofágico , Laparoscopia , Humanos , Fundoplicatura/métodos , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/cirurgia , Metanálise em Rede , Recidiva Local de Neoplasia/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Refluxo Gastroesofágico/cirurgia , Refluxo Gastroesofágico/complicações , Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento
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