Effect of abnormal expression of miR-141 on malignant biological behav-iors of human hepatocarcinoma cells / 中国病理生理杂志

ABSTRACT

AIM:To investigate the expression of microRNA-141 (miR-141) in human hepatocellular carcino-ma (HCC) cell line SMMC-7721 and normal hepatocyte line HL-7702, and to analyze the effect of abnormal expression of miR-141 on the malignant biological behaviors of human hepatocarcinoma cells.METHODS:The RNA from SMMC-7721 cells and HL-7702 cells was extracted.SYBR Green real-time PCR was performed to detect the expression of miR-141. Synthetic miR-141 mimic and its negative control were transfected into the SMMC-7721 cells, and miR-141 inhibitor and its negative control were transfected into the HL-7702 cells by the method of Lipofectamine.After transfection, MTS assay and BrdU-ELISA were employed to evaluate the effect of miR-141 on the cell proliferation.Flow cytometry was used to detect cell cycle and apoptosis.The changes of migration ability were investigated by Transwell invasion assay.RESULTS:The expression of miR-141 in the SMMC-7721 cells was significantly lower than that in the HL-7702 cells ( P<0.05 ) .Com-pared with blank group, Lipofectamine group and negative control group, the proliferation of the SMMC-7721 cells trans-fected with 25 nmol/L miR-141 mimic was significantly inhibited in a time-dependent manner (P<0.05).The percenta-ges of G1 phase cells and early apoptotic rate were significantly increased when miR-141 was up-regulated, but the migra-tion ability was inhibited (P<0.05).Compared with blank group, Lipofectamine group and negative control group, the proliferation of HL-7702 cells transfected with 50 nmol/L miR-141 inhibitor was significantly increased in a time-dependent manner (P<0.05).When miR-141 was down-regulated, the percentages of G1 phase cells and early apoptotic rate were significantly decreased, but the migration ability was enhanced (P<0.05).CONCLUSION:miR-141 is down-regulated in human hepatocarcinoma cell line.Up-regulation of miR-141 will not only inhibit cell proliferation and migration ability, but also affect the cell cycle and apoptosis of SMMC-7721 cells.miR-141 may function as a tumor suppressor gene during HCC development.