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1.
Biomark Res ; 12(1): 40, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38637902

RESUMO

BACKGROUND: IL-15 plays a vital role in enhancing NK cell- and T-cell-mediated antitumor immune responses; however, the direct effect of IL-15 on tumor cells has not been fully elucidated. Herein, we investigated the effect of IL-15 on lung adenocarcinoma cells. METHODS: Silencing and overexpression techniques were used to modify endogenous IL-15 expression in tumor cells. Transwell assays were used to assess tumor cell migration and invasion; a live-cell analysis system was used to evaluate cell motility; cellular morphological changes were quantified by confocal fluorescence microscopy; the molecular mechanisms underlying the effect of IL-15 on tumor cells were analyzed by western blotting; and RhoA and Cdc42 activities were evaluated by a pulldown assay. NCG and C57BL/6 mouse models were used to evaluate the functions of IL-15 in vivo. RESULTS: Cancer cell-intrinsic IL-15 promoted cell motility and migration in vitro and metastasis in vivo via activation of the AKT-mTORC1 pathway; however, exogenous IL-15 inhibited cell motility and migration via suppression of the RhoA-MLC2 axis. Mechanistic analysis revealed that both the intracellular and extracellular IL-15-mediated effects required the expression of IL-15Rα by tumor cells. Detailed analyses revealed that the IL-2/IL-15Rß and IL-2Rγ chains were undetected in the complex formed by intracellular IL-15 and IL-15Rα. However, when exogenous IL-15 engaged tumor cells, a complex containing the IL-15Rα, IL-2/IL-15Rß, and IL-2Rγ chains was formed, indicating that the differential actions of intracellular and extracellular IL-15 on tumor cells might be caused by their distinctive modes of IL-15 receptor engagement. Using a Lewis lung carcinoma (LLC) metastasis model, we showed that although IL-15 overexpression facilitated the lung metastasis of LLC cells, IL-15-overexpressing LLC tumors were more sensitive to anti-PD-L1 therapy than were IL-15-wild-type LLC tumors via an enhanced antitumor immune response, as evidenced by their increased CD8+ T-cell infiltration compared to that of their counterparts. CONCLUSIONS: Cancer cell-intrinsic IL-15 and exogenous IL-15 differentially regulate cell motility and migration. Thus, cancer cell-intrinsic IL-15 acts as a double-edged sword in tumor progression. Additionally, high levels of IL-15 expressed by tumor cells might improve the responsiveness of tumors to immunotherapies.

2.
Cancer Res ; 83(13): 2262-2277, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37145144

RESUMO

IFNγ-mediated signaling in tumor cells can induce immunosuppressive responses and cause tumor resistance to immunotherapy. Blocking TGFß promotes T lymphocyte infiltration and turns immunologically cold tumors into hot tumors, thereby improving the efficacy of immunotherapy. Several studies have shown that TGFß inhibits IFNγ signaling in immune cells. We thus sought to determine whether TGFß affects IFNγ signaling in tumor cells and plays a role in the development of acquired resistance to immunotherapy. TGFß stimulation of tumor cells increased SHP1 phosphatase activity in an AKT-Smad3-dependent manner, decreased IFNγ-mediated tyrosine phosphorylation of JAK1/2 and STAT1, and suppressed the expression of STAT1-dependent immune evasion-related molecules, e.g., PD-L1, IDO1, herpes virus entry mediator (HVEM), and galectin-9 (Gal-9). In a lung cancer mouse model, dual blockade of TGFß and PD-L1 led to superior antitumor activity and prolonged survival compared with anti-PD-L1 therapy alone. However, prolonged combined treatment resulted in tumor resistance to immunotherapy and increased expression of PD-L1, IDO1, HVEM, and Gal-9. Interestingly, after initial anti-PD-L1 monotherapy, dual TGFß and PD-L1 blockade promoted both immune evasion gene expression and tumor growth compared with that in tumors treated with continuous PD-L1 monotherapy. Alternatively, treatment with JAK1/2 inhibitor following initial anti-PD-L1 therapy effectively suppressed tumor growth and downregulated immune evasion gene expression in tumors, indicating the involvement of IFNγ signaling in immunotherapy resistance development. These results demonstrate an unappreciated effect of TGFß on the development of IFNγ-mediated tumor resistance to immunotherapy. SIGNIFICANCE: Blocking TGFß facilitates IFNγ-mediated resistance to anti-PD-L1 therapy due to the role of TGFß in inhibiting IFNγ-induced immunoevasion by increasing SHP1 phosphatase activity in tumor cells.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Camundongos , Animais , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Proteínas Proto-Oncogênicas c-akt , Fator de Crescimento Transformador beta , Evasão da Resposta Imune , Adenocarcinoma de Pulmão/genética , Interferon gama , Neoplasias Pulmonares/patologia , Imunoterapia/métodos , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral
3.
Front Oncol ; 10: 571684, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33154946

RESUMO

BACKGROUND: The incidence rates of early-stage non-small cell lung cancer (NSCLC) are now increasing, and therapies such as thermal ablation have shown potential therapeutic promise. This study aimed to determine the influence of different surgical methods on overall survival (OS) and cancer-specific survival (CSS) in patients with stage I NSCLC. METHODS: Patients diagnosed with stage I NSCLC who had received thermal ablation or wedge resection between 2004 and 2014 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was performed according to the surgical method. Kaplan-Meier curves and a Cox proportional hazard model were used to evaluate OS and CSS. RESULTS: In all, 4,372 patients with stage I NSCLC were included. Before PSM, the respective 3- and 5-year OS rates were 68.9 and 52.7% in the wedge resection group and 68.5 and 47.8% in the thermal ablation group (p < 0.0001); the corresponding CSS rates were 79.1 and 69.4% and 62.6 and 46.0% (p < 0.0001). After PSM, survival analysis showed that wedge resection had better OS (44.5% vs. 30.1%, p = 0.033) and CSS (63.5% vs. 46%, p = 0.038) than thermal ablation. After PSM, Cox regression showed that treatment was not associated with OS or CSS. For patients aged >75 years, thermal ablation showed similar OS and CSS as wedge resection (OS: 30.6% vs. 41.7%, p = 0.470; CSS: 46.4% vs. 64.1%, p = 0.100). After PSM, thermal ablation still had OS (30.6% vs. 41.0%, p = 0.470) and CSS (46.4% vs. 59.8%, p = 0.100) comparable to wedge resection. CONCLUSION: For patients with stage I NSCLC who are unfit for lobectomy, thermal ablation could be a potential therapeutic option, especially for those >75 years old.

4.
Artif Intell Med ; 102: 101756, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31980095

RESUMO

Early detection of skin cancer is very important and can prevent some skin cancers, such as focal cell carcinoma and melanoma. Although there are several reasons that have bad impacts on the detection precision. Recently, the utilization of image processing and machine vision in medical applications is increasing. In this paper, a new image processing based method has been proposed for the early detection of skin cancer. The method utilizes an optimal Convolutional neural network (CNN) for this purpose. In this paper, improved whale optimization algorithm is utilized for optimizing the CNN. For evaluation of the proposed method, it is compared with some different methods on two different datasets. Simulation results show that the proposed method has superiority toward the other compared methods.


Assuntos
Redes Neurais de Computação , Neoplasias Cutâneas/diagnóstico , Algoritmos , Animais , Carcinoma/diagnóstico , Simulação por Computador , Bases de Dados Factuais , Diagnóstico por Computador , Diagnóstico Precoce , Humanos , Processamento de Imagem Assistida por Computador , Melanoma/diagnóstico , Comportamento Predatório , Baleias
5.
Cell Physiol Biochem ; 51(5): 2160-2171, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30522099

RESUMO

BACKGROUND/AIMS: KRas is usually mutated in non-small cell lung cancer (NSCLC). The mutated KRas gene is a negative prognostic indicator that promotes tumor proliferation, metastasis, and drug resistance in NSCLC, and thus has become a target for cancer therapy. This study is focused on the effects of the microRNA (miR)-202/KRas axis in regulating chemosensitivity in NSCLC. METHODS: Quantitative reverse transcriptase real-time PCR analysis was performed to examine the expression of miR-202. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays were performed to evaluate the sensitivity of cisplatin against NSCLC cells. The miR-202/KRas axis was confirmed by western blot and luciferase reporter assays. Cell apoptosis was measured by flow cytometry. KRas expression, MEK1/2 and ERK1/2 phosphorylation, and activation of caspase-9 and caspase-3 were detected by western blot. RESULTS: A significant decrease in miR-202 expression was observed in NSCLC cells both in vivo and in vitro. In addition, miR-202 expression was associated with drug resistance. Recovery of miR-202 expression levels was found to increase the sensitivity of both NCI-H441 and A549 NSCLC cells to cisplatin treatment. Mechanically, as the Ras/mitogen-activated protein kinase (MAPK) pathway was aberrantly activated in NCI-H441 and A549 NSCLC cells, the overexpression of miR-202 was found to inhibit the Ras/MAPK pathway by targeting the KRas gene. As a result, increased miR-202 expression expanded apoptosis signaling induced by cisplatin in NSCLC cells. CONCLUSION: The miR-202/KRas axis controlled the chemosensitivity of NSCLC by mediating the Ras/MAPK pathway. Thus, the combination of platinum-based drugs with miR-202 may represent a novel strategy to enhance the anti-tumor effect against NSCLC.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Cisplatino/farmacologia , Neoplasias Pulmonares/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Células A549 , Animais , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/efeitos dos fármacos
6.
Front Aging Neurosci ; 6: 66, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24782763

RESUMO

Helicobacter pylori (H. pylori) infection is related with a high risk of Alzheimer's disease (AD), but the intrinsic link between H. pylori infection and AD development is still missing. In the present study, we explored the effect of H. pylori infection on cognitive function and ß-amyloid production in rats. We found that intraperitoneal injection of H. pylori filtrate induced spatial learning and memory deficit in rats with a simultaneous retarded dendritic spine maturation in hippocampus. Injection of H. pylori filtrate significantly increased Aß42 both in the hippocampus and cortex, together with an increased level of presenilin-2 (PS-2), one key component of γ-secretase involved in Aß production. Incubation of H. pylori filtrate with N2a cells which over-express amyloid precursor protein (APP) also resulted in increased PS-2 expression and Aß42 overproduction. Injection of Escherichia coli (E.coli) filtrate, another common intestinal bacterium, had no effect on cognitive function in rats and Aß production in rats and cells. These data suggest a specific effect of H. pylori on cognition and Aß production. We conclude that soluble surface fractions of H. pylori may promote Aß42 formation by enhancing the activity of γ-secretase, thus induce cognitive impairment through interrupting the synaptic function.

7.
Zhongguo Fei Ai Za Zhi ; 17(5): 417-23, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-24854560

RESUMO

BACKGROUND AND OBJECTIVE: Despite undergoing curative resection, the 5-year survival rate for stage III non-small cell lung cancer (NSCLC) patients is less than 25%. There is a need for biomarkers for prediction of survival and guiding individual therapy. MiR-155 is one of most commonly upregulated miRNAs in malignancies, and regulates multiple pro-oncogenic pathways. We aimed to investigate the prognostic impact of miR-155 in resected stage III NSCLC patients. METHODS: Tumor formalin-fixed, paraffin-embedded (FFPE) from 162 resected stage III NSCLC patients were collected. Total RNA including miRNA was extracted, and qRT-PCR was used to determine the expression of miR-155. RESULTS: Spearman rank correlation test showed a positive correlation between miR-155 expression and nodal status (r=0.169, P=0.032). MiR-155 expression had a significant prognostic impact in the total cohort (P<0.001), in squamous cell carcinomas (P=0.002) and in adenocarcinomas (P=0.003). In N0-1 subgroup, miR-155 expression did not have a significant prognostic on overall survival in univariate analysis (P=0.319). In N2 subgroup, miR-155 had a negative prognostic effect on OS in univariate analysis (P<0.001). Cox regression analysis revealed that miR-155 expression was unfavorable prognostic factors of OS (RR=2.311, 95%CI: 1.479-3.611, P<0.001). CONCLUSIONS: High expression of miR-155 represents a valuable marker of poor clinical outcomes in patients with stage III NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Adulto Jovem
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