MicroRNA-122 targets zinc finger and BTB domain containing 20 regulating the invasion and migration of gastric cancer by Wnt signaling pathway

Abstract

Objective To investigate the effect of microRNA (miRNA, miR)-122 targeting zinc finger and BTB domain containing 20 (ZBTB20) on Wnt signaling pathway on invasion and metastasis of gastric cancer. Methods The expression of miR-122 in gastric carcinoma was detected by real-time fluorescent quantitative polymerase chain reaction (FQ-PCR). The expression of ZBTB20 in gastric cancer cell lines was detected by western blotting. The effect of miR-122 on the transcriptional activity of ZBTB20 was examined by the dual luciferase reporter gene system. Transwell invasion assay was used to detect the expression of miR-122 in the gastric cancer cell line SGC-7901. To detect the expression of ZBTB20 after slience miR-122 by Western blotting. Western blotting was used to detect the protein expression of Wnt signal pathway after silencing ZBTB20. The protein expression of ZBTB20 was detected by Western blotting. The ablity of vitro tumorigenesis of SGC-7901 gastric carcinoma cells after overexpressing miR-122 in nude mice was detected by tumorigenesis experiment. Results The expression of miR-122 and ZBTB20 was low in gastric cancer tissues (2.51±0.31 vs. 0.58±0.17, P=0.009). The expression of miR-122 was significantly lower in SGC-7901 than that other cell lines. After overexpression of miR-122, the invasion and migration ability of gastric cancer cell line SGC-7901 was significantly decreased [(18.62±2.32)% vs. (35.92±2.48)%, P=0.029; (34.25±5.75)% vs. (62.19±7.23)%, P=0.032; (49.73±3.91)% vs. (85.24±6.29)%, P=0.026]. The dual luciferase reporter gene system showed that miR-122 can directly regulate the transcriptional activity of ZBTB20. After overexpression of miR-122 in gastric cancer cells. The expression level of ZBTB20 was down-regulated after silencing ZBTB20, and the expression of Wnt, c-Myc and Cyclin D1 protein were down-regulated after miR-122 overexpression [(12.32±0.81)% vs. (81.45±3.69)%; (15.64±1.11)% vs. (88.45±8.34)%, (13.52±0.71)% vs. (79.45±3.76)%, P=0.043]. Gastric cancer SGC-7901 cell line in vitro tumorigenic ability decreased after overexpression of miR-122 [Volume (3.09±0.23) cm3 vs. (0.45±0.12) cm3,P=0.029; Weight (2.85±0.35) g vs. (0.48±0.14) g, P=0.018]. Conclusion miR-122 targets the expression of ZBTB20 and regulates the invasion and migration of gastric cancer cells. Key words: MicroRNA-122; zinc finger and BTB domain containing 20; Wnt; Gastric cancer