Targeted regulation of microRNA?3677 on BTG1 expression and its effect on invasion and migration of hep?atocellular carcinoma cells

WEI Shiping; YIN Xiaoyan; TIAN Xinli; LI Hongyong; LI Na

doi:10.3969/j.issn.1009-0460.2019.08.004

Abstract：Objective To investigate the the targeted regulation of microRNA-3677 (miR-3677) on B cell translocation gene 1 (BTG1) and invasion and migration of hepatocellular carcinoma (HCC) HepG2 cells. Methods The HepG2 cells were transfected with miR-3677 inhibitor (Inhibitor group) and negative control ( NC group) by the liposome Lipofectamine 2000, and untransfected cells were used as Control group. Real-time quantitative polymerase chain reaction (QPCR) was used to detect the level of miR-3677. The scratch width and number of transmembrane cells were detected by cell scratch test and Transwell test, respectively. Double lucif-erase reporter gene assay was used to verify the targeting relationship between miR-3677 and BTG1. The mRNA levels of BTG1, matrix metalloproteinase-9 (MMP-9) and signal transducer and activator of transcription 3 (STAT3) were detected by QPCR.The protein lev-els of BTG1, MMP-9, STAT3 and phospho-STAT3 ( p-STAT3) were detected by Western blotting. Results QPCR showed that the miR-3677 level in Inhibitor group was 0. 241±0. 059, lower than 1. 012±0. 123 in Control group and 1. 147±0. 168 in NC group ( P＜0. 05). The number of transmembrane cells and relative scratch width in Inhibitor group were 96. 5±9. 2 and (62. 15±3. 29)%, supe-rior to 174. 5±12. 9 and (37. 45±2. 16)% in Control group and 181. 6± 16. 4 and (39. 47± 2. 82)% in NC group ( P＜0. 05). MiR-3677 mimics significantly inhibited the relative luciferase activity of wild-type 3′untranslated region of BTG1, but had no effect on mu-tant BTG1 luciferase activity. Compared with other two groups, the increased levels of BTG1 and decreased levels of MMP-9 and p- STAT3 were observed in Inhibitor group (P＜0. 05). Conclusion Downregulation of miR-3677 can inhibit the migration and invasion of HCC cells. This miRNA plays an oncogene role, which may be related to the activation of JAK／STAT3 signal transduction by targe-ting BTG1, thus providing a new potential therapeutic target for HCC.