RESUMO
Genomic profiling can provide prognostic and predictive information to guide clinical care. Biomarkers that reliably predict patient response to chemotherapy and immune checkpoint inhibition in gastric cancer are lacking. In this retrospective analysis, we use our machine learning algorithm NTriPath to identify a gastric-cancer specific 32-gene signature. Using unsupervised clustering on expression levels of these 32 genes in tumors from 567 patients, we identify four molecular subtypes that are prognostic for survival. We then built a support vector machine with linear kernel to generate a risk score that is prognostic for five-year overall survival and validate the risk score using three independent datasets. We also find that the molecular subtypes predict response to adjuvant 5-fluorouracil and platinum therapy after gastrectomy and to immune checkpoint inhibitors in patients with metastatic or recurrent disease. In sum, we show that the 32-gene signature is a promising prognostic and predictive biomarker to guide the clinical care of gastric cancer patients and should be validated using large patient cohorts in a prospective manner.
Assuntos
Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Gástricas/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fluoruracila/uso terapêutico , Gastrectomia , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/patologia , TranscriptomaRESUMO
In the current study, it was demonstrated that the hot water extract of I. obliquus (IOWE) exerts inhibitory activity against the proliferation of human colon cancer cells (HT-29). The inhibitory effect of IOWE on the growth of HT-29 cancer cells was evaluated by treating cells with IOWE at concentrations of 0.25, 0.5 and 1.0 mg/mL for 24 or 48 h. The IOWE inhibited cell growth in a dose-dependent manner, and this inhibition was accompanied by apoptotic cell death. The maximum inhibitory effect (56%) was observed when IOWE was treated at a concentration of 1.0 mg/mL for 48 h. The apoptotic effect of IOWE on HT-29 cells was also confirmed by flow cytometric analysis. In addition, the apoptotic cell percentage was closely associated with down-regulation of Bcl-2 and up-regulation of Bax and caspase-3. The results suggest that IOWE would be useful as an antitumor agent via the induction of apoptosis and inhibition of the growth of cancer cells through up-regulation of the expression of proapoptotic proteins and down-regulation of antiapoptotic proteins.
Assuntos
Agaricales/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Sobrevivência Celular , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
In the present study, optimum culture conditions for the production of extracellular polysaccharides (EPS) in submerged culture of an edible mushroom, Laetiporus sulphureus var. miniatus and their stimulatory effects on insulinoma cell (RINm5F) proliferation and insulin secretion were investigated. The maximum mycelial growth (4.1 g l(-1)) and EPS production (0.6 g l(-1)) in submerged flask culture were achieved in a medium containing 30 g l(-1) maltose, 2 g l(-1) soy peptone, and 2 mM MnSO(4).5H2O at an initial pH 2.0 and temperature 25 degrees C. In the stirred-tank fermenter under optimized medium, the concentrations of mycelial biomass and EPS reached a maximum level of 8.1 and 3.9 g l(-1), respectively. Interestingly, supplementation of deep sea water (DSW) into the culture medium significantly increased both mycelial biomass and EPS production by 4- and 6.7-fold at 70% (v/v) DSW medium, respectively. The EPS were proved to be glucose-rich polysaccharides and were able to increase proliferation and insulin secretary function of rat insulinoma RINm5F cells, in a dose-dependent manner. In addition, EPS also strikingly reduced the streptozotocin-induced apoptosis in RINm5F cells indicating the mode of the cytoprotective role of EPS on RINm5F cells.
Assuntos
Técnicas de Cultura de Células/métodos , Insulina/metabolismo , Micélio/metabolismo , Polyporales/metabolismo , Polissacarídeos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Reatores Biológicos , Carbono/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidores do Crescimento/farmacologia , Concentração de Íons de Hidrogênio , Minerais/metabolismo , Micélio/crescimento & desenvolvimento , Nitrogênio/metabolismo , Polyporales/crescimento & desenvolvimento , Polissacarídeos/química , Polissacarídeos/farmacologia , Ratos , Estreptozocina/farmacologia , TemperaturaRESUMO
Bioactivity-guided fractionation of Saururus chinensis (Saururaceae) using a lymphoproliferation assay led us to isolate 5 lignans (compounds 1 - 5). Compounds 1 - 5 were identified as sauchinone, (-)-saucerneol, saucerneol C, manassantin A, and manassantin B, respectively, by spectroscopic analyses. The immunosuppressive activities of the active compounds were evaluated using lymphoproliferation, mixed leukocyte response, and Th1/Th2 cytokine assays. The relative potency was in the order: manassantin A, B > (-)-saucerneol > saucerneol C > sauchinone.