MiRNA-195 Sensitizes Human Hepatocellular Carcinoma Cells To 5-FU By Targeting BCL-w

Objective: This study is to investigate the effects of miR-195 and its mechanism on 5-fluracil sensitivity in BEL-7402/5-FU by Targeting BCL-w.Method: MicroRNA microarray analyzed a wide diversity in miRNA expression between BEL-7402 and BEL-7402/5-FU cells. miR-195s or Anti- miR-195(miR-195a), was transient transfected into BEL-7402 and BEL-7402/5-FU cells, respectively. Luciferase assays to identify putative miR-195 targets. Transfection efficiency was tested by fluorescence inverted microscope and Quantitative Real-Time Reverse-Transcription PCR. Cell viability of each group was measured by MTT assay. Cell apoptotic percentage was detected by flow cytometry. Western blot was used to detect the protein expression.Result: MicroRNA microarray showed that 2 miRNAs were significant (>2- fold) up-regulation (eg.miR-192 and miR-194) and many miRNAs were down-regulation (<0.5-fold) (eg. miR-195,miR-18a, miR-429, et al) in the BEL-7402/5-FU compared with BEL-7402 cells. MTT results showed that miR-195s transfectants had a higher cell inhibition rate than untreated cells or negative. MiR-195 promoted the sensitivity of BEL-7402/5-FU and BEL-7402 to 5-FU. Flow cytometry results demonstrated that miR-195s transfected cells had a higher apoptosis rate than untreated cells or negative. Moreover, miR-195s transfected cells had significant move value than untreated cells or negative by 5-FU (1 and 10μmol/ml) for 24 hours. Western bolt results showed that the expression level of Bax in miR-195s transfected cells were obviously increased, while the expression level of Bcl-w,Bcl-XL,Bcl-2 were obviously decreased compared with untreated cells or negative.Conclusion: 1 miR-195s increased cell spontaneous apoptosis and sensitized BEL-7402/5-FU cells to 5-FU; 2 miR-195s down-regulate Bcl-w,Bcl-XL,Bcl-2 expressions and up-regulate Bax expressions in BEL-7402/5-FU cells; 3 miR-195s could play a role in the development of acquiring resistance in hepatocellular carcinoma cells by modulating apoptosis via targeting Bcl-w.