Effects Of MiR-21 On Biological Properties Of HeLa Cervical Cancer Cells

Objective:We regulated the expression of miR-21 in cervical cancer HeLa cells ,to investigate the effects of miR-21 up-expression and down-expression on proliferation,migration and invasion ability of HeLa cells.Methods:The HeLa cells were divided into five groups: miR-21 up-regulation group, miR-21 down-regulation group, miRNA precursor negative control group, miRNA inhibitor negative control group and blank control group. Through LipofectamineTM 2000, the cells in miR-21 up-regulation group were transfected with Pre-miRTM miR-21 Precursor Molecule, the cells in miR-21 down-regulation group were transfected with Anti-miRTM miR-21 Inhibitor(anti-miR-21 oligonucleotides,AMOs) and the cells in negative control group were transfected with miRNA precursor negative control and miRNA inhibitor negative control.The miR-21 expression was measured by quantitative Real Time-PCR.Cellular proliferation capacity were assayed by the methyl thiazolyl tetrazolium(MTT)assay. Cellular migration and invasion ability were detected by cell scratch wound and Transwell chamber assay.Results:1,The result of quantitative Real Time-PCR showed: after incubation with miR-21 precursor for 48h, the level of miR-21 in miR-21 up-regulation group was up-regulated significantly compared with that of the control group(P<0.01),while the level of miR-21 in miR-21 down-regulation group was decreased by anti-miR-21 oligonucleotides compared with the control group(P<0.01). 2,The result of MTT assay showed: after incubation for 48h and 72h,the cell proliferation ability of the miR-21 up-regulation group was increased 15%-17% compared with that of the control group(P<0.05);while the cell proliferation ability of the miR-21 down-regulation group was reduced 13%-20% compared with that of the control group(P<0.05).3,The result of the cell scratch wound assay showed: compared with that of the control group ,the number of cells in the miR-21 up-regulation group which cross the wound region was more significantly after incubation for 48h and 72h; on the contrary, the number of cells in miR-21 down-regulation group which cross the wound region was less compared with the control group.4,The result of Transwell invasion assay showed: the number of cells invasion of the miR-21 up-regulation group was 216±24;the number of cells invasion of the miR-21 down-regulation group was 53±6;the number of cells invasion of the miRNA precursor negative control group was 122±15; the number of cells invasion of the miRNA inhibitor negative control group was 115±10; the number of cells invasion of the blank control group was 115±14. There were different significances between the miR-21 up-regulation group and the control group(P<0.01) and there were different significances between the miR-21 down-regulation group and the control group(P<0.01).Conclusions:1,miR-21 precursor can up-regulated the level of miR-21 and anti-miR-21 oligonucleotides can down-regulated the level of miR-21 in HeLa cells.2,After the up-regulated expression of miR-21, the cellular proliferation ability was enhanced and the activity of cellular migration and invasion were positively regulated in HeLa cells; after the down-regulated expression of miR-21, the ability of cellular proliferation,migration and invasion were inhibited.3,miR-21 is closely related with the development of cervical cancer.