RESUMO
5-Fluorouracil (5-FU) as a chemotherapeutic drug is used to treat colorectal cancer (CRC). However, 5-FU is associated with acquired CRC resistance, which decreases the therapeutic potential of 5-FU. Several studies indicated that miR-200c is also involved in chemotherapeutic drug resistance, but the exact mechanism of miR-200c mediated chemoresistance has not yet been fully understood. In this study, we examined the effect of inhibition of miR-200c on the sensitivity of HCT-116 cells to 5-FU. HCT-116 cells were transfected with LNA-anti- miR-200c for 48 h. mRNA expression of miR-200c was investigated by qRT-PCR. The protein expression of phosphatase and tensin homolog (PTEN) and E-cadherin were evaluated by western blotting. Annexin V/ PI staining and caspase 3 activity were used to detect apoptosis. LNA-anti-miR-200c inhibited the miR-200c expression in the transfected cells compared with that in the control group. LNA-anti-miR-200c suppressed the expression of PTEN and E-cadherin independent of the presence of the chemotherapeutic drug 5-FU. LNA-anti-miR-200c reduced the 5-FU-induced apoptosis and caspase 3 activity. miR-200c, as a novel prognostic marker in CRC, can be a potential therapeutic approach to overcome chemoresistance during 5-FU chemotherapy.
Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , MicroRNAs/genética , Antígenos CD , Apoptose/efeitos dos fármacos , Caderinas/genética , Caderinas/metabolismo , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Humanos , MicroRNAs/antagonistas & inibidores , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Células Tumorais CultivadasRESUMO
OBJECTIVE: colorectal cancer (CRC) is one of the most common malignancies, associated with high rates of relapse. A notable challenge in treatment is low response rate to current therapies for advanced CRC. The miR-200c plays an essential role in tumor suppression by inhibiting epithelial-mesenchymal transition (EMT). Resveratrol, a natural compound found in red wine, reveals anti-cancer properties in several types of cancers such as CRC. The aim of current study was to evaluate the effects of resveratrol on proliferation, apoptosis, and invasion of HCT-116 cells and also expression of EMT-related genes in presences or absence of miR-200c. METHODS: the effect of resveratrol on viability was examined by MTT assay. LNA-anti-miR-200c transfection of HCT-116 cells was carried out in a time dependent manner. Then, the expression of miR-200c and EMT-related genes were quantified by qRT-PCR. Further, expression of EMT-related proteins, apoptosis, and invasion were analyzed by Western blot, Annexin V/PI staining and scratch test, respectively. RESULTS: resveratrol could significantly inhibit viability of HCT-116 cells. LNA-anti-miR-200c suppressed the endogenous miR-200c in transfected cells compared with the control. qRT-PCR and Western blot analysis of LNA-anti-miR-200c transfected cells revealed a considerable increase in vimentin and ZEB-1 expression, with a concomitant reduction in E-cadherin expression level. Migration of HCT-116 cells increased, and apoptosis significantly reduced in transfected cells. While, resveratrol could entirely reverse these changes by modulation of miR-200c expression. CONCLUSION: our findings revealed a major role of resveratrol in apoptosis, invasion, and switching of EMT to MET phenotype through upregulation of miR-200c in CRC. J. Cell. Biochem. 118: 1547-1555, 2017. © 2016 Wiley Periodicals, Inc.