Abstract: Abstract:Objective To investigate effects of microRNA-506 (miR-506) on malignant phenotypes of hepatocellular carcinoma (HCC) cells, including cellular viability, proliferation and invasion. Methods HCC cell lines HepG2 and QGY- 7703 were served as model. Five experimental groups were established in this study, including cell control, pcDNA3 blank vector control, miR-506 over-expression, pSIH1 blank vector control and miR-506 suppression groups. Real-time reverse transcription PCR assay was performed to measure miR- 506 level. CCK- 8, colony formation and Transwell assays were performed to detect viability, colony formation activity and invasion activity of HCC cell lines, respectively. Effects of miR- 506 on these indexes were evaluated. Results In HepG2 and QGY-7703 cell lines, miR-506 level increased in the miR- 506 over-expression group (P＜0.01), and its level decreased in the miR-506 suppression group (P＜0.05) compared with the related blank vector control groups. In the miR-506 over-expression group, cellular viability was significantly reduced (P＜0.01), cell colony number decreased, and number of cell penetrating Transwell microporous membrane was also decreased (P＜0.01). In the miR- 506 suppression group, cellular viability significantly increased (P＜0.01), and both colony number and penetrating cell number increased (P＜0.05). Also, there were no effects on the above indexes in pcDNA3 and pSIH1 blank vector control groups compared with those of cell control group (P＞0.05). Conclusion miR- 506 plays a tumor suppressor role in HCC cells by inhibiting cell viability, colony formation and invasion.

Key words: microRNAs, liver neoplasms, genes, tumor suppressor, neoplasm invasiveness, cell viability, miR-506