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1.
Cell ; 175(4): 984-997.e24, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30388455

RESUMO

Immune checkpoint inhibitors (ICIs) produce durable responses in some melanoma patients, but many patients derive no clinical benefit, and the molecular underpinnings of such resistance remain elusive. Here, we leveraged single-cell RNA sequencing (scRNA-seq) from 33 melanoma tumors and computational analyses to interrogate malignant cell states that promote immune evasion. We identified a resistance program expressed by malignant cells that is associated with T cell exclusion and immune evasion. The program is expressed prior to immunotherapy, characterizes cold niches in situ, and predicts clinical responses to anti-PD-1 therapy in an independent cohort of 112 melanoma patients. CDK4/6-inhibition represses this program in individual malignant cells, induces senescence, and reduces melanoma tumor outgrowth in mouse models in vivo when given in combination with immunotherapy. Our study provides a high-resolution landscape of ICI-resistant cell states, identifies clinically predictive signatures, and suggests new therapeutic strategies to overcome immunotherapy resistance.


Assuntos
Antineoplásicos/uso terapêutico , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Melanoma/imunologia , Inibidores de Proteínas Quinases/uso terapêutico , Linfócitos T/imunologia , Evasão Tumoral , Idoso , Idoso de 80 Anos ou mais , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Imunoterapia/métodos , Masculino , Melanoma/tratamento farmacológico , Melanoma/terapia , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia
2.
Nature ; 615(7950): 158-167, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36634707

RESUMO

Despite the success of PD-1 blockade in melanoma and other cancers, effective treatment strategies to overcome resistance to cancer immunotherapy are lacking1,2. Here we identify the innate immune kinase TANK-binding kinase 1 (TBK1)3 as a candidate immune-evasion gene in a pooled genetic screen4. Using a suite of genetic and pharmacological tools across multiple experimental model systems, we confirm a role for TBK1 as an immune-evasion gene. Targeting TBK1 enhances responses to PD-1 blockade by decreasing the cytotoxicity threshold to effector cytokines (TNF and IFNγ). TBK1 inhibition in combination with PD-1 blockade also demonstrated efficacy using patient-derived tumour models, with concordant findings in matched patient-derived organotypic tumour spheroids and matched patient-derived organoids. Tumour cells lacking TBK1 are primed to undergo RIPK- and caspase-dependent cell death in response to TNF and IFNγ in a JAK-STAT-dependent manner. Taken together, our results demonstrate that targeting TBK1 is an effective strategy to overcome resistance to cancer immunotherapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Evasão da Resposta Imune , Imunoterapia , Proteínas Serina-Treonina Quinases , Humanos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Imunoterapia/métodos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Organoides , Fatores de Necrose Tumoral/imunologia , Interferon gama/imunologia , Esferoides Celulares , Caspases , Janus Quinases , Fatores de Transcrição STAT
4.
J Am Chem Soc ; 146(26): 17801-17816, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38887845

RESUMO

Gangliosides, sialic acid bearing glycosphingolipids, are components of the outer leaflet of plasma membranes of all vertebrate cells. They contribute to cell regulation by interacting with proteins in their own membranes (cis) or their extracellular milieu (trans). As amphipathic membrane constituents, gangliosides present challenges for identifying their ganglioside protein interactome. To meet these challenges, we synthesized bifunctional clickable photoaffinity gangliosides, delivered them to plasma membranes of cultured cells, then captured and identified their interactomes using proteomic mass spectrometry. Installing probes on ganglioside lipid and glycan moieties, we captured cis and trans ganglioside-protein interactions. Ganglioside interactomes varied with the ganglioside structure, cell type, and site of the probe (lipid or glycan). Gene ontology revealed that gangliosides engage with transmembrane transporters and cell adhesion proteins including integrins, cadherins, and laminins. The approach developed is applicable to other gangliosides and cell types, promising to provide insights into molecular and cellular regulation by gangliosides.


Assuntos
Química Click , Gangliosídeos , Gangliosídeos/química , Gangliosídeos/metabolismo , Humanos , Marcadores de Fotoafinidade/química , Marcadores de Fotoafinidade/síntese química , Sondas Moleculares/química , Sondas Moleculares/síntese química , Membrana Celular/metabolismo , Membrana Celular/química
5.
Cancer Immunol Immunother ; 73(4): 74, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38451314

RESUMO

BACKGROUND: Pembrolizumab has been indicated in the treatment of solid tumors with high frequency microsatellite instability (MSI-H) or high tumor mutational burden (TMB-H); however, real-world data on the effectiveness of pembrolizumab with or without chemotherapy in this molecular subset remain limited. Our retrospective study evaluated the clinical efficacy and safety of pembrolizumab in treating advanced solid tumors with either MSI-H or TMB-H. METHODS: This retrospective study analyzed data from 116 patients with MSI-H or TMB-H advanced solid cancers who received pembrolizumab with or without chemotherapy regardless of treatment setting. We analyzed objective response rate (ORR) and progression-free survival (PFS). RESULTS: The top three cancer types were colorectal (48.6% MSI-H, 6.5% TMB-H), lung (15.4% MSI-H, 84.4% TMB-H), and gastric (15.4% MSI-H, 5.1% TMB-H). The ORR with pembrolizumab was 52.6%, including complete response (CR) observed in 8.6% (n = 10) of cases and partial responses (PR) in 43.9% (n = 51). Of the 93 patients who received first-line pembrolizumab, 52 patients achieved objective response (10 CR, 42 PR), with a median PFS of 14.0 months (95% confidence intervals [CI] 6.6-21.4). Of the 23 who received subsequent-line pembrolizumab, the ORR was 39.1%, disease control rate was 91.3%, and median PFS was 5.7 months (95% CI 3.9-7.5). Treatment-related adverse events were observed in 32 patients (27.6%), with no reported treatment-related fatal adverse events. CONCLUSION: Our study provides real-world evidence on the clinical effectiveness of pembrolizumab with or without chemotherapy in the treatment of patients with MSI-H and TMB-H advanced solid cancers.


Assuntos
Anticorpos Monoclonais Humanizados , Instabilidade de Microssatélites , Neoplasias , Humanos , Estudos Retrospectivos , Neoplasias/tratamento farmacológico , Neoplasias/genética , China , Resposta Patológica Completa
6.
J Neuroinflammation ; 21(1): 43, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317227

RESUMO

Glaucoma is a complex neurodegenerative disorder characterized by the progressive loss of retinal ganglion cells (RGC) and optic nerve axons, leading to irreversible visual impairment. Despite its clinical significance, the underlying mechanisms of glaucoma pathogenesis remain poorly understood. In this study, we aimed to unravel the multifaceted nature of glaucoma by investigating the interaction between T cells and retinas. By utilizing clinical samples, murine glaucoma models, and T cell transfer models, we made several key findings. Firstly, we observed that CD4+ T cells from glaucoma patients displayed enhanced activation and a bias towards T helper (Th) 1 responses, which correlated with visual impairment. Secondly, we identified the infiltration of Th1 cells into the retina, where they targeted RGC and integrated into the pro-inflammatory glial network, contributing to progressive RGC loss. Thirdly, we discovered that circulating Th1 cells upregulated vascular cell adhesion protein 1 (VCAM-1) on retinal microvessels, facilitating their entry into the neural retina. Lastly, we found that Th1 cells underwent functional reprogramming before reaching the retina, acquiring a phenotype associated with lymphocyte migration and neurodegenerative diseases. Our study provides novel insights into the role of peripheral CD4+ T cells in glaucoma pathogenesis, shedding light on the mechanisms underlying their infiltration into the retina and offering potential avenues for innovative therapeutic interventions in this sight-threatening disease.


Assuntos
Glaucoma , Células Ganglionares da Retina , Humanos , Camundongos , Animais , Células Ganglionares da Retina/patologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , Células Th1/patologia , Glaucoma/metabolismo , Retina/patologia , Transtornos da Visão/patologia , Modelos Animais de Doenças
7.
J Transl Med ; 22(1): 880, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39350123

RESUMO

BACKGROUND: Patients with glioblastoma (GBM) have a poor prognosis and limited treatment options. The mRNA decapping enzyme scavenger (DCPS) is a cap-hydrolyzing enzyme. The DCPS inhibitor RG3039 exhibited excellent central nervous system bioavailability in vivo and was safe and well tolerated in healthy volunteers in a phase 1 clinical trial. In this study, we investigated the expression of DCPS in GBM and the anti-tumor activity of RG3039 in various preclinical models of GBM. METHODS: DCPS expression was examined in human GBM and paired peritumoral tissues. Its prognostic role was evaluated together with clinicopathological characteristics of patients. The anti-GBM effect of RG3039 was determined using GBM cell lines, patient-derived organoids, and orthotopic mouse models. The therapeutic mechanisms of DCPS inhibition were explored. RESULTS: DCPS is overexpressed in GBM and is associated with poor survival of patients with GBM. The DCPS inhibitor RG3039 exhibited robust anti-GBM activities in GBM cell lines, patient-derived organoids and orthotopic mouse models, with drug exposure achievable in humans. Mechanistically, RG3039 downregulated STAT5B expression, thereby suppressing proliferation, survival and colony formation of GBM cells. CONCLUSIONS: DCPS is a promising target for GBM. Inhibition of DCPS with RG3039 at doses achievable in humans downregulates STAT5B expression and reduces proliferation, survival and colony formation of GBM cells. Given the excellent anti-cancer activity and central nervous system bioavailability in vivo and good tolerance in humans, RG3039 warrants further study as a potential GBM therapy.


Assuntos
Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/genética , Glioblastoma/metabolismo , Animais , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Endorribonucleases/metabolismo , Endorribonucleases/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Feminino , Masculino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Camundongos Nus , Camundongos , Organoides/efeitos dos fármacos , Organoides/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Pessoa de Meia-Idade
8.
Mol Cell Biochem ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39085744

RESUMO

Brain metastasis (BM) in laryngeal squamous cell carcinoma (LSCC) is uncommon but prognosis is poor. Anti-PD-1 immunotherapy benefits some advanced LSCC cases, yet its efficiency is limited by tumor complexity. We analyzed paired metastatic tumor samples from before and after immunotherapy using single-cell RNA sequencing (scRNA-seq), along with a primary LSCC dataset and bulk RNA sequencing. This identified changes post-immunotherapy and revealed differences in single-cell transcriptomes among LSCC, primBM, and neoBM. Our findings show that anti-PD-1 treatment suppresses metastasis-promoting pathways like VEGF and EMT in cancer cells, and alters immune cell functions. Notably, it upregulates T cell activation, leading to CD8 T cell exhaustion from excess heat shock proteins, notably HSPA8. However, CD8 T cell cytotoxic functions improve post-treatment. In myeloid cells, anti-PD-1 therapy enhances antigen presentation and promotes a proinflammatory shift post-metastasis. Additionally, NUPR1 is linked to BM in LSCC, and NEAT1 is a potential metastatic cancer cell cycle participant. Our study provides insights into cancer heterogeneity and the impact of PD-1 immunotherapy on metastasis, aiding precise diagnosis and prognosis.

9.
Org Biomol Chem ; 22(5): 965-969, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38205855

RESUMO

A visible-light-induced decarboxylative cascade reaction of acryloylbenzamides with alkyl N-hydroxyphthalimide (NHP) esters for the synthesis of various 4-alkyl isoquinolinediones mediated by triphenylphosphine (PPh3) and sodium iodide (NaI) was developed. This operationally simple protocol proceeded via the photoactivation of electron donor-acceptor (EDA) complexes between N-hydroxyphthalimide esters and NaI/PPh3, resulting in multiple carbon-carbon bond formations without the use of precious metal complexes or synthetically elaborate organic dyes, which provided an alternative practical approach to synthesize diverse isoquinoline-1,3(2H,4H)-dione derivatives.

10.
J Chem Inf Model ; 64(3): 575-583, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38265916

RESUMO

Discovery of small-molecule antibiotics with novel chemotypes serves as one of the essential strategies to address antibiotic resistance. Although a considerable number of computational tools committed to molecular design have been reported, there is a deficit in holistic and efficient tools specifically developed for small-molecule antibiotic discovery. To address this issue, we report AutoMolDesigner, a computational modeling software dedicated to small-molecule antibiotic design. It is a generalized framework comprising two functional modules, i.e., generative-deep-learning-enabled molecular generation and automated machine-learning-based antibacterial activity/property prediction, wherein individually trained models and curated datasets are out-of-the-box for whole-cell-based antibiotic screening and design. It is open-source, thus allowing for the incorporation of new features for flexible use. Unlike most software programs based on Linux and command lines, this application equipped with a Qt-based graphical user interface can be run on personal computers with multiple operating systems, making it much easier to use for experimental scientists. The software and related materials are freely available at GitHub (https://github.com/taoshen99/AutoMolDesigner) and Zenodo (https://zenodo.org/record/10097899).


Assuntos
Inteligência Artificial , Software , Simulação por Computador
11.
Nature ; 560(7718): 382-386, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089911

RESUMO

Tumour cells evade immune surveillance by upregulating the surface expression of programmed death-ligand 1 (PD-L1), which interacts with programmed death-1 (PD-1) receptor on T cells to elicit the immune checkpoint response1,2. Anti-PD-1 antibodies have shown remarkable promise in treating tumours, including metastatic melanoma2-4. However, the patient response rate is low4,5. A better understanding of PD-L1-mediated immune evasion is needed to predict patient response and improve treatment efficacy. Here we report that metastatic melanomas release extracellular vesicles, mostly in the form of exosomes, that carry PD-L1 on their surface. Stimulation with interferon-γ (IFN-γ) increases the amount of PD-L1 on these vesicles, which suppresses the function of CD8 T cells and facilitates tumour growth. In patients with metastatic melanoma, the level of circulating exosomal PD-L1 positively correlates with that of IFN-γ, and varies during the course of anti-PD-1 therapy. The magnitudes of the increase in circulating exosomal PD-L1 during early stages of treatment, as an indicator of the adaptive response of the tumour cells to T cell reinvigoration, stratifies clinical responders from non-responders. Our study unveils a mechanism by which tumour cells systemically suppress the immune system, and provides a rationale for the application of exosomal PD-L1 as a predictor for anti-PD-1 therapy.


Assuntos
Antígeno B7-H1/imunologia , Exossomos/metabolismo , Tolerância Imunológica/imunologia , Melanoma/imunologia , Receptor de Morte Celular Programada 1/imunologia , Evasão Tumoral/imunologia , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/sangue , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Tolerância Imunológica/efeitos dos fármacos , Interferon gama/sangue , Interferon gama/imunologia , Melanoma/tratamento farmacológico , Melanoma/patologia , Camundongos , Camundongos Nus , Metástase Neoplásica , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Evasão Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
BMC Vet Res ; 20(1): 164, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678277

RESUMO

BACKGROUND: Esculentin-1, initially discovered in the skin secretions of pool frogs (Pelophylax lessonae), has demonstrated broad-spectrum antimicrobial activity; however, its immunomodulatory properties have received little attention. RESULTS: In the present study, esculentin-1 cDNA was identified by analysing the skin transcriptome of the dark-spotted frog (Pelophylax nigromaculatus). Esculentin-1 from this species (esculentin-1PN) encompasses a signal peptide, an acidic spacer peptide, and a mature peptide. Sequence alignments with other amphibian esculentins-1 demonstrated conservation of the peptide, and phylogenetic tree analysis revealed its closest genetic affinity to esculentin-1P, derived from the Fukien gold-striped pond frog (Pelophylax fukienensis). Esculentin-1PN transcripts were observed in various tissues, with the skin exhibiting the highest mRNA levels. Synthetic esculentin-1PN demonstrated antibacterial activity against various pathogens, and esculentin-1PN exhibited bactericidal activity by disrupting cell membrane integrity and hydrolyzing genomic DNA. Esculentin-1PN did not stimulate chemotaxis in RAW264.7, a murine leukemic monocyte/macrophage cell line. However, it amplified the respiratory burst and augmented the pro-inflammatory cytokine gene (TNF-α and IL-1ß) expression in RAW264.7 cells. CONCLUSIONS: This novel finding highlights the immunomodulatory activity of esculentin-1PN on immune cells.


Assuntos
Proteínas de Anfíbios , Antibacterianos , Filogenia , Ranidae , Animais , Proteínas de Anfíbios/farmacologia , Proteínas de Anfíbios/química , Proteínas de Anfíbios/genética , Camundongos , Antibacterianos/farmacologia , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/genética , Sequência de Aminoácidos , Pele/metabolismo , Fatores Imunológicos/farmacologia , Fatores Imunológicos/química , Células RAW 264.7 , Alinhamento de Sequência
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(6): 659-664, 2024 Jun 15.
Artigo em Zh | MEDLINE | ID: mdl-38926385

RESUMO

In infants with severe bronchopulmonary dysplasia (sBPD), severe pulmonary lobar emphysema may occur as a complication, contributing to significant impairment in ventilation. Clinical management of these infants is extremely challenging and some may require lobectomy to improve ventilation. However, prior to the lobectomy, it is very difficult to assess whether the remaining lung parenchyma would be able to sustain adequate ventilation postoperatively. In addition, preoperative planning and perioperative management are also quite challenging in these patients. This paper reports the utility of selective bronchial occlusion in assessing the safety and efficacy of lobectomy in a case of sBPD complicated by severe right upper lobar emphysema. Since infants with sBPD already have poor lung development and significant lung injury, lobectomy should be viewed as a non-traditional therapy and be carried out with extreme caution. Selective bronchial occlusion test can be an effective tool in assessing the risks and benefits of lobectomy in cases with sBPD and lobar emphysema. However, given the technical difficulty, successful application of this technique requires close collaboration of an experienced interdisciplinary team.


Assuntos
Displasia Broncopulmonar , Recém-Nascido Prematuro , Enfisema Pulmonar , Humanos , Recém-Nascido , Brônquios , Displasia Broncopulmonar/etiologia , Pneumonectomia , Enfisema Pulmonar/cirurgia
14.
Pharmacol Res ; 192: 106798, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37211240

RESUMO

Exosomes, small extracellular vesicles that function as a key regulator of cell-to-cell communication, are emerging as a promising candidate for bone regeneration. Here, we aimed to investigate the effect of exosomes from pre-differentiated human alveolar bone-derived bone marrow mesenchymal stromal cells (AB-BMSCs) carrying specific microRNAs on bone regeneration. Exosomes secreted from AB-BMSCs pre-differentiated for 0 and 7 days were cocultured with BMSCs in vitro to investigate their effect on the differentiation of the BMSCs. MiRNAs from AB-BMSCs at different stages of osteogenic differentiation were analyzed. BMSCs seeded on poly-L-lactic acid(PLLA) scaffolds were treated with miRNA antagonist-decorated exosomes to verify their effect on new bone regeneration. Exosomes pre-differentiated for 7 days effectively promoted the differentiation of BMSCs. Bioinformatic analysis revealed that miRNAs within the exosomes were differentially expressed, including the upregulation of osteogenic miRNAs (miR-3182, miR-1468) and downregulation of anti-osteogenic miRNAs (miR-182-5p, miR-335-3p, miR-382-5p), causing activation of the PI3K/Akt signaling pathway. The treatment of BMSC-seeded scaffolds with anti-miR-182-5p decorated exosomes demonstrated enhanced osteogenic differentiation and efficient formation of new bone. In conclusion, Osteogenic exosomes secreted from pre-differentiated AB-BMSCs were identified and the gene modification of exosomes provides great potential as a bone regeneration strategy. DATA AVAILABILITY STATEMENT: Data generated or analyzed in this paper partly are available in the GEO public data repository(http://www.ncbi.nlm.nih.gov/geo).


Assuntos
Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Humanos , Osteogênese , Exossomos/genética , Exossomos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Regeneração Óssea/genética , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular
15.
Microb Ecol ; 85(4): 1382-1395, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35583685

RESUMO

Understanding how microbial communities adapt to environmental stresses is critical for interpreting ecological patterns and microbial diversity. In the case of the Gobi Desert, little is known on the environmental factors that explain hypolithic colonization under quartz stones. By analyzing nine hypolithic communities across an arid gradient and the effects of the season of the year in the Hexi Corridor of this desert, we found a significant decrease in hypolithic colonization rates (from 47.24 to 15.73%) with the increasing drought gradient and found two distinct communities in Hot and Cold samples, which survived or proliferated after a hot or a cold period. While Cold communities showed a greater species diversity and a predominance of Cyanobacteria, Hot communities showed a predominance of members of the Proteobacteria and the Firmicutes. In comparison, Cold communities also possessed stronger functions in the photosynthesis and carbon metabolism. Based on the findings of this study, we proposed that the hypolithic communities of the Hexi Corridor of the Gobi Desert might follow a seasonal developmental cycle in which temperature play an important role. Thus after a critical thermal threshold is crossed, heterotrophic microorganisms predominate in the hot period, while Cyanobacteria predominate in the cold period.


Assuntos
Cianobactérias , Microbiota , Estações do Ano , Clima Desértico , Cianobactérias/genética , Temperatura , Microbiologia do Solo
16.
Nature ; 550(7674): 133-136, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28953887

RESUMO

Targeted BRAF inhibition (BRAFi) and combined BRAF and MEK inhibition (BRAFi and MEKi) therapies have markedly improved the clinical outcomes of patients with metastatic melanoma. Unfortunately, the efficacy of these treatments is often countered by the acquisition of drug resistance. Here we investigated the molecular mechanisms that underlie acquired resistance to BRAFi and to the combined therapy. Consistent with previous studies, we show that resistance to BRAFi is mediated by ERK pathway reactivation. Resistance to the combined therapy, however, is mediated by mechanisms independent of reactivation of ERK in many resistant cell lines and clinical samples. p21-activated kinases (PAKs) become activated in cells with acquired drug resistance and have a pivotal role in mediating resistance. Our screening, using a reverse-phase protein array, revealed distinct mechanisms by which PAKs mediate resistance to BRAFi and the combined therapy. In BRAFi-resistant cells, PAKs phosphorylate CRAF and MEK to reactivate ERK. In cells that are resistant to the combined therapy, PAKs regulate JNK and ß-catenin phosphorylation and mTOR pathway activation, and inhibit apoptosis, thereby bypassing ERK. Together, our results provide insights into the molecular mechanisms underlying acquired drug resistance to current targeted therapies, and may help to direct novel drug development efforts to overcome acquired drug resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Melanoma/tratamento farmacológico , Melanoma/genética , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Mutação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Transdução de Sinais/efeitos dos fármacos , Quinases Ativadas por p21/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/química , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/enzimologia , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/química , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-raf/química , Proteínas Proto-Oncogênicas c-raf/metabolismo , Serina-Treonina Quinases TOR/metabolismo , beta Catenina/química , beta Catenina/metabolismo , Quinases Ativadas por p21/antagonistas & inibidores , Quinases Ativadas por p21/genética
17.
Acta Pharmacol Sin ; 44(8): 1637-1648, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36882503

RESUMO

Hepatitis C virus (HCV) infection is one of the major factors to trigger a sustained hepatic inflammatory response and hence hepatocellular carcinoma (HCC), but direct-acting-antiviral (DAAs) was not efficient to suppress HCC development. Heat shock protein 90 kDa (HSP90) is highly abundant in different types of cancers, and especially controls protein translation, endoplasmic reticulum stress, and viral replication. In this study we investigated the correlation between the expression levels of HSP90 isoforms and inflammatory response marker NLRP3 in different types of HCC patients as well as the effect of a natural product celastrol in suppression of HCV translation and associated inflammatory response in vivo. We identified that the expression level of HSP90ß isoform was correlated with that of NLRP3 in the liver tissues of HCV positive HCC patients (R2 = 0.3867, P < 0.0101), but not in hepatitis B virus-associated HCC or cirrhosis patients. We demonstrated that celastrol (3, 10, 30 µM) dose-dependently suppressed the ATPase activity of both HSP90α and HSP90ß, while its anti-HCV activity was dependent on the Ala47 residue in the ATPase pocket of HSP90ß. Celastrol (200 nM) halted HCV internal ribosomal entry site (IRES)-mediated translation at the initial step by disrupting the association between HSP90ß and 4EBP1. The inhibitory activity of celastrol on HCV RNA-dependent RNA polymerase (RdRp)-triggered inflammatory response also depended on the Ala47 residue of HSP90ß. Intravenous injection of adenovirus expressing HCV NS5B (pAde-NS5B) in mice induced severe hepatic inflammatory response characterized by significantly increased infiltration of immune cells and hepatic expression level of Nlrp3, which was dose-dependently ameliorated by pretreatment with celastrol (0.2, 0.5 mg/kg, i.p.). This study reveals a fundamental role of HSP90ß in governing HCV IRES-mediated translation as well as hepatic inflammation, and celastrol as a novel inhibitor of HCV translation and associated inflammation by specifically targeting HSP90ß, which could be developed as a lead for the treatment of HSP90ß positive HCV-associated HCC.


Assuntos
Carcinoma Hepatocelular , Hepatite C , Neoplasias Hepáticas , Camundongos , Animais , Hepacivirus , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Proteínas de Choque Térmico , Proteína 3 que Contém Domínio de Pirina da Família NLR , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Proteínas de Choque Térmico HSP90/metabolismo , Inflamação/tratamento farmacológico
18.
Zhonghua Nan Ke Xue ; 29(7): 630-633, 2023 Jul.
Artigo em Zh | MEDLINE | ID: mdl-38619411

RESUMO

Objective: To observe the clinical effect of Manlyman Spray combined with biofeedback therapy in the treatment of premature ejaculation (PE).Methods: A total of 60 primary premature ejaculation patients with stable sexual partners and regular sexual activity (≥1 times per week) from April 2021 to October 2022 were involved in the clinical observation, The patients' age is (34.3 ± 4.9) years old, and the course of the disease is (112.5 ± 65.5) months, and Manlyman Spray combined with biofeedback therapy was used to treat patients for 8 weeks. Manlyman Spray was sprayed 3 times on the surface of the penisqd for 4 weeks, and Biofeedback therapy is treated twice a week according to the AI setting module, for a total of 8 weeks. Before and 8 weeks after medication and at 4 weeks after drug withdrawal, the Intravaginal Ejaculation Latency Time (IELT), Premature Ejaculation Diagnostic Tool (PEDT) scores and Clinical Global Impression of Change (CGIC) scores were Obtained and compared. Results: After 8 weeks of treatment, the IELT of the patients was significantly prolonged (ï¼»351.4 ± 76.7ï¼½ vs ï¼»87 ± 16.8ï¼½,P<0.05) and at 4 weeks after drug withdrawal, the therapeutic effect still existed (ï¼»345.9 ± 80.3ï¼½ vs ï¼»87 ± 16.8ï¼½,P<0.05), the PEDT scores were significantly improved after treatment (ï¼»18.2 ± 1.1ï¼½ vs ï¼»9.0 ± 1.4ï¼½,P<0.05)and at 4 weeks after drug withdrawal(ï¼»18.0 ± 1.2ï¼½ vs ï¼»9.0 ± 1.4ï¼½,P<0.05), and so were the CGIC scores (ï¼»13.4 ± 1.3ï¼½ vs ï¼»3.3 ± 1.4ï¼½,P<0.05, and ï¼»12.6 ± 1.6ï¼½ vs ï¼»3.3 ± 1.4ï¼½,P<0.05). Conclusion: The combination of Manlyman Spray and biofeedback therapy can effectively treat primary premature ejaculation, with a long duration of treatment and good safety, and the specific mechanism needs further study.


Assuntos
Ejaculação Precoce , Masculino , Humanos , Adulto , Ejaculação Precoce/terapia , Biorretroalimentação Psicológica , Resultado do Tratamento , Ejaculação , Comportamento Sexual
19.
Fa Yi Xue Za Zhi ; 39(2): 129-136, 2023 Apr 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-37277375

RESUMO

OBJECTIVES: To investigate the reliability and accuracy of deep learning technology in automatic sex estimation using the 3D reconstructed images of the computed tomography (CT) from the Chinese Han population. METHODS: The pelvic CT images of 700 individuals (350 males and 350 females) of the Chinese Han population aged 20 to 85 years were collected and reconstructed into 3D virtual skeletal models. The feature region images of the medial aspect of the ischiopubic ramus (MIPR) were intercepted. The Inception v4 was adopted as the image recognition model, and two methods of initial learning and transfer learning were used for training. Eighty percent of the individuals' images were randomly selected as the training and validation dataset, and the remaining were used as the test dataset. The left and right sides of the MIPR images were trained separately and combinedly. Subsequently, the models' performance was evaluated by overall accuracy, female accuracy, male accuracy, etc. RESULTS: When both sides of the MIPR images were trained separately with initial learning, the overall accuracy of the right model was 95.7%, the female accuracy and male accuracy were both 95.7%; the overall accuracy of the left model was 92.1%, the female accuracy was 88.6% and the male accuracy was 95.7%. When the left and right MIPR images were combined to train with initial learning, the overall accuracy of the model was 94.6%, the female accuracy was 92.1% and the male accuracy was 97.1%. When the left and right MIPR images were combined to train with transfer learning, the model achieved an overall accuracy of 95.7%, and the female and male accuracies were both 95.7%. CONCLUSIONS: The use of deep learning model of Inception v4 and transfer learning algorithm to construct a sex estimation model for pelvic MIPR images of Chinese Han population has high accuracy and well generalizability in human remains, which can effectively estimate the sex in adults.


Assuntos
Aprendizado Profundo , Adulto , Feminino , Humanos , Masculino , Imageamento Tridimensional , Pelve , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
20.
EMBO J ; 37(20)2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30209241

RESUMO

Nutrient restriction reprograms cellular signaling and metabolic network to shape cancer phenotype. Lactate dehydrogenase A (LDHA) has a key role in aerobic glycolysis (the Warburg effect) through regeneration of the electron acceptor NAD+ and is widely regarded as a desirable target for cancer therapeutics. However, the mechanisms of cellular response and adaptation to LDHA inhibition remain largely unknown. Here, we show that LDHA activity supports serine and aspartate biosynthesis. Surprisingly, however, LDHA inhibition fails to impact human melanoma cell proliferation, survival, or tumor growth. Reduced intracellular serine and aspartate following LDHA inhibition engage GCN2-ATF4 signaling to initiate an expansive pro-survival response. This includes the upregulation of glutamine transporter SLC1A5 and glutamine uptake, with concomitant build-up of essential amino acids, and mTORC1 activation, to ameliorate the effects of LDHA inhibition. Tumors with low LDHA expression and melanoma patients acquiring resistance to MAPK signaling inhibitors, which target the Warburg effect, exhibit altered metabolic gene expression reminiscent of the ATF4-mediated survival signaling. ATF4-controlled survival mechanisms conferring synthetic vulnerability to the approaches targeting the Warburg effect offer efficacious therapeutic strategies.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Proliferação de Células , Glicólise , L-Lactato Desidrogenase/metabolismo , Melanoma/metabolismo , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Fator 4 Ativador da Transcrição/genética , Sistema ASC de Transporte de Aminoácidos/genética , Sistema ASC de Transporte de Aminoácidos/metabolismo , Ácido Aspártico/biossíntese , Ácido Aspártico/genética , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , L-Lactato Desidrogenase/antagonistas & inibidores , L-Lactato Desidrogenase/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Melanoma/genética , Melanoma/patologia , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Serina/biossíntese , Serina/genética
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