RESUMO
Transcription of viral mRNA in cells infected with influenza viruses involves capturing and cleaving the first 10-20 nucleotides of 5' capped host mRNAs to be used as primers in viral RNA synthesis. A newly developed inhibitor of the viral endonuclease responsible for this cap-snatching shows therapeutic efficacy for the treatment of influenza. To view this Bench to Bedside, open or download the PDF.
Assuntos
Influenza Humana/tratamento farmacológico , Oxazinas/farmacologia , Oxazinas/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Tiepinas/farmacologia , Tiepinas/uso terapêutico , Triazinas/farmacologia , Triazinas/uso terapêutico , Dibenzotiepinas , Endonucleases/genética , Humanos , Morfolinas , Orthomyxoviridae/efeitos dos fármacos , Orthomyxoviridae/patogenicidade , Piridonas , Capuzes de RNA/genética , RNA Mensageiro/genética , RNA Viral/genética , Proteínas Virais/genéticaRESUMO
All cellular proteins are synthesized by ribosomes, whose biogenesis in eukaryotes is a complex multi-step process completed within minutes. Several chemical inhibitors of ribosome function are available and used as tools or drugs. By contrast, we lack potent validated chemical probes to analyze the dynamics of eukaryotic ribosome assembly. Here, we combine chemical and genetic approaches to discover ribozinoindoles (or Rbins), potent and reversible triazinoindole-based inhibitors of eukaryotic ribosome biogenesis. Analyses of Rbin sensitivity and resistance conferring mutations in fission yeast, along with biochemical assays with recombinant proteins, provide evidence that Rbins' physiological target is Midasin, an essential â¼540-kDa AAA+ (ATPases associated with diverse cellular activities) protein. Using Rbins to acutely inhibit or activate Midasin function, in parallel experiments with inhibitor-sensitive or inhibitor-resistant cells, we uncover Midasin's role in assembling Nsa1 particles, nucleolar precursors of the 60S subunit. Together, our findings demonstrate that Rbins are powerful probes for eukaryotic ribosome assembly.
Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Subunidades Ribossômicas Maiores de Eucariotos/efeitos dos fármacos , Subunidades Ribossômicas Maiores de Eucariotos/metabolismo , Proteínas de Schizosaccharomyces pombe/antagonistas & inibidores , Triazinas/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Indóis/química , Indóis/isolamento & purificação , Schizosaccharomyces/efeitos dos fármacos , Schizosaccharomyces/metabolismo , Relação Estrutura-Atividade , Triazinas/química , Triazinas/isolamento & purificaçãoRESUMO
Context-specific molecular vulnerabilities that arise during tumor evolution represent an attractive intervention target class. However, the frequency and diversity of somatic lesions detected among lung tumors can confound efforts to identify these targets. To confront this challenge, we have applied parallel screening of chemical and genetic perturbations within a panel of molecularly annotated NSCLC lines to identify intervention opportunities tightly linked to molecular response indicators predictive of target sensitivity. Anchoring this analysis on a matched tumor/normal cell model from a lung adenocarcinoma patient identified three distinct target/response-indicator pairings that are represented with significant frequencies (6%-16%) in the patient population. These include NLRP3 mutation/inflammasome activation-dependent FLIP addiction, co-occurring KRAS and LKB1 mutation-driven COPI addiction, and selective sensitivity to a synthetic indolotriazine that is specified by a seven-gene expression signature. Target efficacies were validated in vivo, and mechanism-of-action studies informed generalizable principles underpinning cancer cell biology.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Indóis/farmacologia , Neoplasias Pulmonares/metabolismo , Triazinas/farmacologia , Animais , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Transporte , Linhagem Celular Tumoral , Proteína Coatomer/metabolismo , Feminino , Genes ras , Xenoenxertos , Humanos , Neoplasias Pulmonares/patologia , Lisossomos/metabolismo , Camundongos , Terapia de Alvo Molecular , Proteína 3 que Contém Domínio de Pirina da Família NLR , Transplante de Neoplasias , Fosforilação OxidativaRESUMO
The recent emergence of SARS-CoV-2 Omicron (B.1.1.529 lineage) variants possessing numerous mutations has raised concerns of decreased effectiveness of current vaccines, therapeutic monoclonal antibodies and antiviral drugs for COVID-19 against these variants1,2. The original Omicron lineage, BA.1, prevailed in many countries, but more recently, BA.2 has become dominant in at least 68 countries3. Here we evaluated the replicative ability and pathogenicity of authentic infectious BA.2 isolates in immunocompetent and human ACE2-expressing mice and hamsters. In contrast to recent data with chimeric, recombinant SARS-CoV-2 strains expressing the spike proteins of BA.1 and BA.2 on an ancestral WK-521 backbone4, we observed similar infectivity and pathogenicity in mice and hamsters for BA.2 and BA.1, and less pathogenicity compared with early SARS-CoV-2 strains. We also observed a marked and significant reduction in the neutralizing activity of plasma from individuals who had recovered from COVID-19 and vaccine recipients against BA.2 compared to ancestral and Delta variant strains. In addition, we found that some therapeutic monoclonal antibodies (REGN10987 plus REGN10933, COV2-2196 plus COV2-2130, and S309) and antiviral drugs (molnupiravir, nirmatrelvir and S-217622) can restrict viral infection in the respiratory organs of BA.2-infected hamsters. These findings suggest that the replication and pathogenicity of BA.2 is similar to that of BA.1 in rodents and that several therapeutic monoclonal antibodies and antiviral compounds are effective against Omicron BA.2 variants.
Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Anticorpos Neutralizantes/farmacologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/farmacologia , Anticorpos Antivirais/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , COVID-19/genética , COVID-19/imunologia , COVID-19/virologia , Cricetinae , Citidina/análogos & derivados , Combinação de Medicamentos , Hidroxilaminas , Indazóis , Lactamas , Leucina , Camundongos , Nitrilas , Prolina , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Triazinas , TriazóisRESUMO
The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019 has triggered an ongoing global pandemic of the severe pneumonia-like disease coronavirus disease 2019 (COVID-19)1. The development of a vaccine is likely to take at least 12-18 months, and the typical timeline for approval of a new antiviral therapeutic agent can exceed 10 years. Thus, repurposing of known drugs could substantially accelerate the deployment of new therapies for COVID-19. Here we profiled a library of drugs encompassing approximately 12,000 clinical-stage or Food and Drug Administration (FDA)-approved small molecules to identify candidate therapeutic drugs for COVID-19. We report the identification of 100 molecules that inhibit viral replication of SARS-CoV-2, including 21 drugs that exhibit dose-response relationships. Of these, thirteen were found to harbour effective concentrations commensurate with probable achievable therapeutic doses in patients, including the PIKfyve kinase inhibitor apilimod2-4 and the cysteine protease inhibitors MDL-28170, Z LVG CHN2, VBY-825 and ONO 5334. Notably, MDL-28170, ONO 5334 and apilimod were found to antagonize viral replication in human pneumocyte-like cells derived from induced pluripotent stem cells, and apilimod also demonstrated antiviral efficacy in a primary human lung explant model. Since most of the molecules identified in this study have already advanced into the clinic, their known pharmacological and human safety profiles will enable accelerated preclinical and clinical evaluation of these drugs for the treatment of COVID-19.
Assuntos
Antivirais/análise , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Avaliação Pré-Clínica de Medicamentos , Reposicionamento de Medicamentos , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Células Epiteliais Alveolares/citologia , Células Epiteliais Alveolares/efeitos dos fármacos , Betacoronavirus/crescimento & desenvolvimento , COVID-19 , Linhagem Celular , Inibidores de Cisteína Proteinase/análise , Inibidores de Cisteína Proteinase/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hidrazonas , Células-Tronco Pluripotentes Induzidas/citologia , Modelos Biológicos , Morfolinas/análise , Morfolinas/farmacologia , Pandemias , Pirimidinas , Reprodutibilidade dos Testes , SARS-CoV-2 , Bibliotecas de Moléculas Pequenas/análise , Bibliotecas de Moléculas Pequenas/farmacologia , Triazinas/análise , Triazinas/farmacologia , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Tratamento Farmacológico da COVID-19RESUMO
BACKGROUND: The PI3K-mTOR pathway is frequently dysregulated in breast cancer. Combining an inhibitor targeting all class I PI3K isoforms and mTOR complex 1 (mTORC1)-mTOR complex 2 (mTORC2) with endocrine therapy and a CDK4/6 inhibitor might provide more effective tumour control than standard-of-care therapy. To evaluate this hypothesis, gedatolisib, a pan-PI3K-mTOR inhibitor, was assessed in a phase 1b trial combined with palbociclib and endocrine therapy in patients with hormone receptor-positive, HER2-negative, advanced breast cancer. Results from the dose expansion portion of this trial are reported herein. METHODS: This multicentre, open-label, phase 1b study recruited female patients aged at least 18 years from 17 sites across the USA with hormone-receptor-positive, HER2-negative, advanced breast cancer and an Eastern Cooperative Oncology Group performance status of 0-1. Four patient groups were studied in the dose expansion portion of the study: treatment-naive in the advanced setting (first line; group A), progression on 1-2 lines of endocrine therapy but CDK4/6 inhibitor-naive (group B); and one or more previous lines (second-line and higher) of therapy, including a CDK4/6 inhibitor (groups C and D). Gedatolisib 180 mg was administered intravenously weekly in 28-day treatment cycles for groups A-C, and on days 1, 8, and 15 for group D. Letrozole (group A), fulvestrant (groups B-D), and palbociclib (all groups) were administered at standard doses and schedules. The primary endpoint was investigator-assessed objective response rate per RECIST version 1.1 in the evaluable analysis set. This trial is completed and registered with ClinicalTrials.gov, NCT02684032. FINDINGS: Between Dec 19, 2017, and June 19, 2019, 103 female participants were enrolled in the dose expansion groups A (n=31), B (n=13), C (n=32), and D (n=27). Median follow-up was 16·6 months (IQR 5·7-48·4) for group A, 11·0 months (7·6-16·9) for group B, 3·6 months (1·8-7·5) for group C, and 9·4 months (5·3-16·7) for group D for the primary endpoint. Gedatolisib, palbociclib, and endocrine therapy induced an objective response in 23 (85·2%; 90% CI 69·2-94·8) of 27 evaluable first-line participants (group A). In the second-line and higher setting, an objective response was observed in eight (61·5%; 90% CI 35·5-83·4) of 13 evaluable group B participants, seven (25·0%; 12·4-41·9) of 28 evaluable group C participants, and 15 (55·6%; 38·2-72·0) of 27 evaluable group D participants; this included participants with both wild-type and mutated PIK3CA tumours. The most common grade 3-4 treatment-related adverse events were neutropenia (65 [63%] of 103), stomatitis (28 [27%]), and rash (21 [20%]). Grade 3-4 hyperglycaemia was reported in six (6%) participants. 23 (22%) of 103 participants had a treatment-related serious adverse event, and there were no treatment-related deaths. Nine (9%) participants discontinued treatment because of a treatment-emergent adverse event. INTERPRETATION: Gedatolisib plus palbociclib and endocrine therapy showed a promising objective response rate compared with the published results for standard-of-care therapies and had an acceptable safety profile. FUNDING: Pfizer and Celcuity.
Assuntos
Neoplasias da Mama , Morfolinas , Piperazinas , Piridinas , Triazinas , Feminino , Humanos , Adolescente , Adulto , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Receptor ErbB-2/metabolismo , Intervalo Livre de Doença , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Serina-Treonina Quinases TORRESUMO
RsgA (small ribosomal subunit, 30S, GTPase), a late-stage biogenesis factor, releases RbfA from 30S-RbfA complex. Escherichia coli ΔrsgA (deleted for rsgA) shows a slow growth phenotype and an increased accumulation of 17S rRNA (precursor of 16S rRNA) and the ribosomal subunits. Here, we show that the rescue of the ΔrsgA strain by multicopy infB (IF2) is enhanced by simultaneous overexpression of initiator tRNA (i-tRNA), suggesting a role of initiation complex formation in growth rescue. The synergistic effect of IF2/i-tRNA is accompanied by increased processing of 17S rRNA (to 16S), and protection of the 16S rRNA 3'-minor domain. Importantly, we show that an IF2-binding anticonvulsant drug, lamotrigine (Ltg), also rescues the ΔrsgA strain growth. The rescue is accompanied by increased processing of 17S rRNA, protection of the 3'-minor domain of 16S rRNA, and increased 70S ribosomes in polysome profiles. However, Ltg becomes inhibitory to the ΔrsgA strain whose growth was already rescued by an L83R mutation in rbfA. Interestingly, like wild-type infB, overproduction of LtgRinfB alleles (having indel mutations in their domain II) also rescues the ΔrsgA strain (independent of Ltg). Our observations suggest the dual role of IF2 in rescuing the ΔrsgA strain. First, together with i-tRNA, IF2 facilitates the final steps of processing of 17S rRNA. Second, a conformer of IF2 functionally compensates for RsgA, albeit poorly, during 30S biogenesis. IMPORTANCE: RsgA is a late-stage ribosome biogenesis factor. Earlier, infB (IF2) was isolated as a multicopy suppressor of the Escherichia coli ΔrsgA strain. How IF2 rescued the strain growth remained unclear. This study reveals that (i) the multicopy infB-mediated growth rescue of E. coli ΔrsgA and the processing of 17S precursor to 16S rRNA in the strain are enhanced upon simultaneous overexpression of initiator tRNA and (ii) a conformer of IF2, whose occurrence increases when IF2 is overproduced or when E. coli ΔrsgA is treated with Ltg (an anticonvulsant drug that binds to domain II of IF2), compensates for the function of RsgA. Thus, this study reveals yet another role of IF2 in ribosome biogenesis.
Assuntos
Proteínas de Escherichia coli , Escherichia coli , Lamotrigina , Ribossomos , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos , Lamotrigina/farmacologia , Ribossomos/metabolismo , Fator de Iniciação 2 em Procariotos/metabolismo , Fator de Iniciação 2 em Procariotos/genética , RNA Ribossômico 16S/genética , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Regulação Bacteriana da Expressão Gênica , RNA de Transferência de Metionina/metabolismo , RNA de Transferência de Metionina/genética , Triazinas/farmacologia , Triazinas/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , GTP Fosfo-HidrolasesRESUMO
Quinone analogue molecules, functioning as herbicides, bind to the secondary quinone site, QB, in type-II photosynthetic reaction centers, including those from purple bacteria (PbRC). Here, we investigated the impact of herbicide binding on electron transfer branches, using herbicide-bound PbRC crystal structures and employing the linear Poisson-Boltzmann equation. In contrast to urea and phenolic herbicides [Fufezan, C. Biochemistry 2005, 44, 12780-12789], binding of atrazine and triazine did not cause significant changes in the redox-potential (Em) values of the primary quinone (QA) in these crystal structures. However, a slight Em difference at the bacteriopheophytin in the electron transfer inactive branch (HM) was observed between the S(-)- and R(+)-triazine-bound PbRC structures. This discrepancy is linked to variations in the protonation pattern of the tightly coupled Glu-L212 and Glu-H177 pairs, crucial components of the proton uptake pathway in native PbRC. These findings suggest the existence of a QB-mediated link between the electron transfer inactive HM and the proton uptake pathway in PbRCs.
Assuntos
Atrazina , Herbicidas , Complexo de Proteínas do Centro de Reação Fotossintética , Triazinas , Herbicidas/química , Herbicidas/metabolismo , Atrazina/química , Atrazina/metabolismo , Transporte de Elétrons , Triazinas/química , Triazinas/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/química , Oxirredução , Modelos Moleculares , Rhodobacter sphaeroides/metabolismo , Cristalografia por Raios XRESUMO
Vital to the treatment of influenza is the use of antivirals such as Oseltamivir (Tamiflu) and Zanamivir (Relenza); however, antiviral resistance is becoming an increasing problem for these therapeutics. The RNA-dependent RNA polymerase acidic N-terminal (PAN) endonuclease, a critical component of influenza viral replication machinery, is an antiviral target that was recently validated with the approval of Baloxavir Marboxil (BXM). Despite its clinical success, BXM has demonstrated susceptibility to resistance mutations, specifically the I38T, E23K, and A36 V mutants of PAN. To better understand the effects of these mutations on BXM resistance and improve the design of more robust therapeutics, this study examines key differences in protein-inhibitor interactions with two inhibitors and the I38T, E23K, and A36 V mutants. Differences in inhibitor binding were evaluated by measuring changes in binding to PAN using two biophysical methods. The binding mode of two distinct inhibitors was determined crystallographically with both wild-type and mutant forms of PAN. Collectively, these studies give some insight into the mechanism of antiviral resistance of these mutants.
Assuntos
Dibenzotiepinas , Influenza Humana , Morfolinas , Tiepinas , Humanos , Oxazinas , Piridinas/farmacologia , Antivirais/farmacologia , Antivirais/uso terapêutico , Endonucleases/genética , Tiepinas/farmacologia , Tiepinas/uso terapêutico , Piridonas/uso terapêutico , Oseltamivir/farmacologia , Oseltamivir/uso terapêutico , Zanamivir/uso terapêutico , Triazinas/farmacologia , Triazinas/uso terapêuticoRESUMO
Coccidia of the genus Eimeria are specialized intracellular parasitic protozoa that cause severe coccidiosis when they infect their hosts. Animals infected with Eimeria develop clinical symptoms, such as anorexia, diarrhea, and hematochezia, which can even cause death. Although the current preferred regimen for the treatment of coccidiosis is antibiotics, this treatment strategy is limited by the ban on antibiotics and the growing problem of drug resistance. Therefore, the exploration of alternative methods for controlling coccidiosis has attracted much attention. Lactobacillus plantarum has been shown to have many beneficial effects. In this study, L. plantarum M2 was used as a research object to investigate the effect of L. plantarum on intestinal inflammation induced by infection with Eimeria falciformis in mice by detecting indicators, such as oocyst output, serum cytokines, and the intestinal microbiota. Compared with that in the infection group, the percent weight loss of the mice that were administered with L. plantarum M2 was significantly reduced (P < 0.05). Supplemented L. plantarum M2 and probiotics combined with diclazuril can reduce the total oocyst output significantly (P < 0.05, P < 0.001). L. plantarum M2 had outstanding performance in maintaining intestinal barrier function, and the levels of the mucin MUC1 and the tight junction protein E-cadherin were significantly elevated (P < 0.01, P < 0.05). Studies have shown that probiotic supplementation can alleviate adverse reactions after infection and significantly improve intestinal barrier function. In addition, probiotics combined with diclazuril could optimize the partial efficacy of diclazuril, which not only enhanced the effect of antibiotics but also alleviated their adverse effects. This study expands the application of probiotics, provides new ideas for alternative strategies for coccidia control, and suggests a basis for related research on lactobacilli antagonizing intracellular pathogen infection.IMPORTANCECoccidia of the genus Eimeria are specialized intracellular parasitic protozoa, and the current preferred regimen for the treatment of coccidiosis is antibiotics. However, due to antibiotic bans and drug resistance, the exploration of alternative methods for controlling coccidiosis has attracted much attention. In this work, we focused on Lactobacillus plantarum M2 and found that probiotic supplementation can alleviate adverse reactions after infection and improve intestinal barrier function. This study proposes the possibility of using lactic acid bacteria to control coccidiosis, and its potential mechanism needs further exploration.
Assuntos
Coccidiose , Eimeria , Lactobacillus plantarum , Probióticos , Animais , Coccidiose/parasitologia , Eimeria/efeitos dos fármacos , Probióticos/uso terapêutico , Probióticos/administração & dosagem , Camundongos , Citocinas/sangue , Citocinas/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Oocistos , Modelos Animais de Doenças , Nitrilas , TriazinasRESUMO
Artificial photosynthesis represents a sustainable strategy for accessing high-value chemicals; however, the conversion efficiency is significantly limited by its difficulty in the cycle of coenzymes such as NADH. In this study, we report a series of isostructural triazine covalent organic frameworks (COFs) and explore their N-substituted microenvironment-dependent photocatalytic activity for NADH regeneration. We discovered that the rational alteration of N-heterocyclic species, which are linked to the triazine center through an imine linkage, can significantly regulate both the electron band structure and planarity of a COF layer. This results in different separation efficiencies of the photoinduced electron-hole pairs and electron transfer behavior within and between individual layers. The optimal COF catalyst herein achieves an NADH regeneration capacity of 89% within 20 min, outperforming most of the reported nanomaterial photocatalysts. Based on this, an artificial photosynthesis system is constructed for the green synthesis of a high-value compound, L-glutamate, and its conversion efficiency significantly surpasses the enzymatic approach without the NADH photocatalytic cycle. This work offers new insights into the coenzyme regeneration by means of regulating the distal heterocyclic microenvironment of a COF skeleton, holding great potential for the green photosynthesis of important chemicals.
Assuntos
Estruturas Metalorgânicas , Triazinas , Triazinas/química , Catálise , Estruturas Metalorgânicas/química , NAD/química , NAD/metabolismo , Processos Fotoquímicos , Estrutura Molecular , Coenzimas/química , Coenzimas/metabolismo , FotossínteseRESUMO
BACKGROUND: Pediatric-type diffuse high-grade glioma (pHGG) is the most frequent malignant brain tumor in children and can be subclassified into multiple entities. Fusion genes activating the MET receptor tyrosine kinase often occur in infant-type hemispheric glioma (IHG) but also in other pHGG and are associated with devastating morbidity and mortality. METHODS: To identify new treatment options, we established and characterized two novel orthotopic mouse models harboring distinct MET fusions. These included an immunocompetent, murine allograft model and patient-derived orthotopic xenografts (PDOX) from a MET-fusion IHG patient who failed conventional therapy and targeted therapy with cabozantinib. With these models, we analyzed the efficacy and pharmacokinetic properties of three MET inhibitors, capmatinib, crizotinib and cabozantinib, alone or combined with radiotherapy. RESULTS: Capmatinib showed superior brain pharmacokinetic properties and greater in vitro and in vivo efficacy than cabozantinib or crizotinib in both models. The PDOX models recapitulated the poor efficacy of cabozantinib experienced by the patient. In contrast, capmatinib extended survival and induced long-term progression-free survival when combined with radiotherapy in two complementary mouse models. Capmatinib treatment increased radiation-induced DNA double-strand breaks and delayed their repair. CONCLUSIONS: We comprehensively investigated the combination of MET inhibition and radiotherapy as a novel treatment option for MET-driven pHGG. Our seminal preclinical data package includes pharmacokinetic characterization, recapitulation of clinical outcomes, coinciding results from multiple complementing in vivo studies, and insights into molecular mechanism underlying increased efficacy. Taken together, we demonstrate the groundbreaking efficacy of capmatinib and radiation as a highly promising concept for future clinical trials.
Assuntos
Neoplasias Encefálicas , Glioma , Proteínas Proto-Oncogênicas c-met , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Humanos , Glioma/patologia , Glioma/tratamento farmacológico , Glioma/genética , Glioma/terapia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Camundongos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Linhagem Celular Tumoral , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Feminino , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Crizotinibe/farmacologia , Crizotinibe/uso terapêutico , Modelos Animais de Doenças , Criança , Gradação de Tumores , Anilidas/farmacologia , Imidazóis , TriazinasRESUMO
Using the GISAID EpiCoV database, we identified 256 COVID-19 patients in Japan during March 31-December 31, 2023, who had mutations in the SARS-CoV-2 nonstructural protein 5 conferring ensitrelvir resistance. Ongoing genomic surveillance is required to monitor emergence of SARS-CoV-2 mutations that are resistant to anticoronaviral drugs.
Assuntos
Antivirais , COVID-19 , Farmacorresistência Viral , Mutação , SARS-CoV-2 , Humanos , Japão/epidemiologia , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/virologia , Farmacorresistência Viral/genética , Antivirais/uso terapêutico , Antivirais/farmacologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Proteínas não Estruturais Virais/genética , Tratamento Farmacológico da COVID-19 , Indazóis , Triazinas , TriazóisRESUMO
During development, embryos and foetuses may be exposed to maternally ingested antiseizure medications (ASM), valproate and lamotrigine, essential in some patients to control their epilepsy symptoms. Often, the two drugs are co-administered to reduce required doses of valproate, a known potential teratogen. This study used Genetic Absence Epilepsy Rat from Strasbourg to evaluate transfer of valproate and lamotrigine across late gestation placenta and their entry into cerebrospinal fluid (CSF) and brain of developing rats, in mono- and combination therapies. Animals at embryonic day (E) 19, postnatal day (P) 0, 4 and 21, and adults were administered valproate (30 mg/kg) or lamotrigine (6 mg/kg) with their respective [3H]-tracers, either alone or in combination. In chronic experiments, females consumed valproate-containing diet from 2 weeks prior to mating until offspring were used at E19 and P0. Drugs were injected 30 min before blood, CSF and brain samples were collected from terminally anaesthetised animals. Radioactivity in samples was measured. In acute monotherapy brain entry of valproate was higher in foetal than postnatal animals, correlating with its plasma protein binding. Brain entry of lamotrigine was not age-dependent. Combination therapy enhanced entry of lamotrigine into the adult brain but had no effects on brain and CSF entry of valproate. Following chronic valproate exposure, placental transfer of valproate decreased in combination therapy; however, foetal brain entry increased. Results suggest that during pregnancy, the use of combination therapy of valproate and lamotrigine may mitigate overall foetal exposure to valproate but potential risks to foetal brain development are less clear.
Assuntos
Anticonvulsivantes , Encéfalo , Epilepsia Tipo Ausência , Lamotrigina , Placenta , Triazinas , Ácido Valproico , Animais , Feminino , Gravidez , Anticonvulsivantes/administração & dosagem , Epilepsia Tipo Ausência/tratamento farmacológico , Epilepsia Tipo Ausência/genética , Epilepsia Tipo Ausência/metabolismo , Ratos , Placenta/metabolismo , Placenta/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Triazinas/administração & dosagem , Troca Materno-Fetal , MasculinoRESUMO
Antiviral susceptibility of influenza viruses was assessed using a high-content imaging-based neutralization test. Cap-dependent endonuclease inhibitors, baloxavir and AV5116, were superior to AV5115 against type A viruses, and AV5116 was most effective against PA mutants tested. However, these three inhibitors displayed comparable activity (EC50 8-22 nM) against type C viruses from six lineages. Banana lectin and a monoclonal antibody, YA3, targeting the hemagglutinin-esterase protein effectively neutralized some, but not all, type C viruses.
Assuntos
Antivirais , Dibenzotiepinas , Triazinas , Antivirais/farmacologia , Humanos , Triazinas/farmacologia , Dibenzotiepinas/farmacologia , Gammainfluenzavirus/efeitos dos fármacos , Gammainfluenzavirus/genética , Morfolinas/farmacologia , Piridonas/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Células Madin Darby de Rim Canino , Cães , Ciclopropanos/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Testes de Neutralização , Piridinas/farmacologiaRESUMO
MHY1485 is an mTOR activator that inhibits the autophagy process by inhibiting the fusion between autophagosomes and lysosomes. This study aimed to explore the role and mechanism of MHY1485 in hepatocellular carcinoma (HCC) and to provide an in-depth understanding of the mechanisms of autophagy regulation in relation to adriamycin (ADM) resistance, as well as the development of a molecularly targeted autophagy-modulating approach. Here, ADM was used to treat HepG2 cells and construct an ADM-resistant cell model. The HepG2/ADM cell line and HepG2 cells were treated with MHY1485 and ADM, respectively, and the proliferation and apoptosis of HCC cells were detected using CCK8, clone formation, flow cytometry, and 5-ethynyl-2'-deoxyuridine staining assays. Ki-67, mTOR phosphorylation, and LC3A expression were detected by IF staining; the expression or phosphorylation levels of autophagy-related proteins (i.e., GLUT1, PGI, PFK, END, and MTHFD2) and apoptosis-related proteins (caspase-3, caspase-8, and caspase-9) were detected by qPCR and western blotting. The number of autophagosomes was determined by monodansylcadaverine staining. Our results showed that MHY1485 can inhibit the proliferation and growth of liver cancer cells, and that MHY1485 combined with ADM can effectively inhibit the tolerance of HepG2/ADM cells to ADM and enhance the efficacy of ADM. The results of the detection of the autophagy-related protein LC3A also indicated that MHY1485 activates mTOR and can affect the phosphorylation level of ULK1, inhibit autophagy, and enhance the sensitivity of liver cancer cells to adriamycin. In summary, MHY1485 can enhance the sensitivity of adriamycin-resistant cells to adriamycin by activating mTOR and blocking the autophagy process in cells; therefore, mTOR may become a potential target for the treatment of liver cancer.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Morfolinas , Triazinas , Humanos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Doxorrubicina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Células Hep G2 , Apoptose , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Autofagia , Proliferação de Células , Linhagem Celular TumoralRESUMO
Data regarding the use of FMS-like tyrosine kinase 3 (FLT3) and isocitrate dehydrogenase 1/2 (IDH1/2) inhibitors in acute lymphoblastic leukaemia (ALL) are lacking. We identified 14 patients with FLT3- or IDH1/2-mutated ALL. Three early T-cell precursor-ALL patients received FLT3 or IDH2 inhibitors. Patient 1 maintains a complete remission (CR) with enasidenib after intolerance to chemotherapy. Patient 2 maintained a CR for 27 months after treatment with enasidenib for relapsed disease. Patient 3 was treated with venetoclax and gilteritinib at the time of relapse and maintained a CR with gilteritinib for 8 months. These cases suggest that FLT3 and IDH inhibitors could represent a viable therapeutic option for ALL patients with these mutations.
Assuntos
Aminopiridinas , Compostos de Anilina , Leucemia Mieloide Aguda , Leucemia-Linfoma Linfoblástico de Células Precursoras , Pirazinas , Triazinas , Humanos , Tirosina Quinase 3 Semelhante a fms/genética , Recidiva Local de Neoplasia , Inibidores Enzimáticos/uso terapêutico , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia Mieloide Aguda/genéticaRESUMO
Baloxavir marboxil (BXM) is approved for treating uncomplicated influenza. The active metabolite baloxavir acid (BXA) inhibits cap-dependent endonuclease activity of the influenza virus polymerase acidic protein (PA), which is necessary for viral transcription. Treatment-emergent E23G or E23K (E23G/K) PA substitutions have been implicated in reduced BXA susceptibility, but their effect on virus fitness and transmissibility, their synergism with other BXA resistance markers, and the mechanisms of resistance have been insufficiently studied. Accordingly, we generated point mutants of circulating seasonal influenza A(H1N1)pdm09 and A(H3N2) viruses carrying E23G/K substitutions. Both substitutions caused 2- to 13-fold increases in the BXA EC50. EC50s were higher with E23K than with E23G and increased dramatically (138- to 446-fold) when these substitutions were combined with PA I38T, the dominant BXA resistance marker. E23G/K-substituted viruses exhibited slightly impaired replication in MDCK and Calu-3 cells, which was more pronounced with E23K. In ferret transmission experiments, all viruses transmitted to direct-contact and airborne-transmission animals, with only E23K+I38T viruses failing to infect 100% of animals by airborne transmission. E23G/K genotypes were predominantly stable during transmission events and through five passages in vitro. Thermostable PA-BXA interactions were weakened by E23G/K substitutions and further weakened when combined with I38T. In silico modeling indicated this was caused by E23G/K altering the placement of functionally important Tyr24 in the endonuclease domain, potentially decreasing BXA binding but at some cost to the virus. These data implicate E23G/K, alone or combined with I38T, as important markers of reduced BXM susceptibility, and such mutants could emerge and/or transmit among humans.
Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Influenza Humana , Tiepinas , Substituição de Aminoácidos , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Dibenzotiepinas , Farmacorresistência Viral/genética , Endonucleases/metabolismo , Furões , Humanos , Vírus da Influenza A Subtipo H1N1/metabolismo , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/metabolismo , Vírus da Influenza A/genética , Vírus da Influenza A/metabolismo , Morfolinas , Oxazinas/farmacologia , Piridinas/farmacologia , Piridonas/farmacologia , Tiepinas/farmacologia , Triazinas , Proteínas Virais/metabolismoRESUMO
Antiviral therapy based on neuraminidase (oseltamivir) or polymerase (baloxavir marboxil) inhibitors plays an important role in the management of influenza infections. However, the emergence of drug resistance and the uncontrolled inflammatory response are major limitations in the treatment of severe influenza disease. Protectins D1 (PD1) and DX (PDX), part of a family of pro-resolving mediators, have previously demonstrated anti-influenza activity as well as anti-inflammatory properties in various clinical contexts. Herein, we synthetized a series of simplified PDX analogs and assessed their in vitro antiviral activity against influenza A(H1N1) viruses, including oseltamivir- and baloxavir-resistant variants. In ST6GalI-MDCK cells, the PDX analog AN-137B reduced viral replication in a dose-dependent manner with IC50 values of 23.8 for A/Puerto Rico/8/1934 (H1N1) and between 32.6 and 36.7 µM for susceptible and resistant A(H1N1)pdm09 viruses. In MTS-based cell viability experiments, AN-137B showed a 50% cellular cytotoxicity (CC50 ) of 638.7 µM with a resulting selectivity index of 26.8. Of greater importance, the combination of AN-137B with oseltamivir or baloxavir resulted in synergistic and additive in vitro effects, respectively. Treatment of lipopolysaccharide (LPS)-stimulated macrophages with AN-137B resulted in a decrease of iNOS activity as shown by the reduction of nitrite production, suggesting an anti-inflammatory effect. In conclusion, our results indicate that the protectin analog AN-137B constitutes an interesting therapeutic modality against influenza A virus, warranting further evaluation in animal models.
Assuntos
Dibenzotiepinas , Ácidos Docosa-Hexaenoicos , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Influenza Humana , Morfolinas , Piridonas , Triazinas , Animais , Humanos , Oseltamivir/farmacologia , Oseltamivir/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Influenza Humana/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Farmacorresistência Viral , NeuraminidaseRESUMO
Avapritinib, a highly selective inhibitor of KIT D816V, was approved by the Food and Drug Administration in 2021 for treatment of advanced systemic mastocytosis (AdvSM) and by the European Medicines Agency in 2022 for AdvSM after prior systemic therapy. The phase 1 EXPLORER and phase 2 PATHFINDER trials demonstrated that avapritinib can elicit complete and durable clinical responses and molecular remission of KIT D816V. Key management challenges relate to the complex mutational landscape of AdvSM, often found with an associated hematologic neoplasm.