Inhibitory effects of knocking down microRNA-19a and microRNA-19b on glioma cell growth in vitro

objective To investigate the effects of knocking down of miR-19a and miR-19b on the biological characteristics of SNB19 glioblastoma cells. Methods Oligonucleotides inhibitor of miR-19a and miR-19b (miR-19a inhibitor or miR-19b inhibitor) mediated by lipofectamine2000 were transfected to SNB19 cells to knock down miR-19a and miR-19b; control group (without transfection),group D (performing transfection with nonsense sequence) and group E (performing transfection with both miR-19a inhibitor and miR-19b inhibitor) were established. Real time PCR was conducted to detect the expressions ofmiR-19a and miR-19b in these groups after the transfection. The cell proliferation rate and cell cycle kinetics were detected by 3-(4, 5-Dime- -thylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and flow cytometry, respectively; the cell invasive ability was evaluated by Transwell assay.Results As compared with those in control group and group D, the expressions of miR-19a and miR-19b, proliferation activity and invasive ability of cells in the miR-19a/19b inhibitor transfected cells (group A/B) were significantly reduced (P＜0.05). The expressions of miR-19a and miR-19b and the proliferation activity and invasive ability of cells 2, 3, 4 and 5 d after the transfection in group E were significantly reduced as compared with those in group A/B (P＜0.05). Delayed cell cycle in group A/B and group E was noted as compared with that in control group and group D; and group E enjoyed more obviously delayed eell cycle than group A/B (P＜0.05). Conclusion MiR-19a and miR-19b might be oncomiRs, and may be candidate target miRNAs for gene therapy of glioma. Key words: Micro RANs;  Glioma;  Proliferation;  Invasion