Expression of sex determining region Y-box 2 in hepatocellular carcinoma tissues and effect on the SMMC-7721 proliferation, invasion and migration

Abstract

Objective To investigate the association between the clinical significance and the expression of sex determining region Y-box 2 (SOX2) in hepatocellular carcinoma (HCC), and to elucidate the its effect on proliferation, migration and invasion of SMMC-7721 cells. Methods We evaluated the clinical significance of SOX2 in 32 HCC patients using immunohistochemistry. The effects of SOX2 on the proliferation, invasion and migration of HCC cells were detected by clone formation and Transwell assay in vitro. Results The expression of SOX2 was up-regulated in the human HCC tissues. The positive rate of SOX2 in cancer tissue, para cancer tissue and normal liver tissue was 73.8%, 32.5% and 12.4%, respectively (P=0.008, 0.006). Clone formation experiment results showed that clone formation number of SOX2 overexpression cells (654.9±39.4) was significantly greater than that of control group (232.7±19.4, P=0.000). In vitro, the characteristics of epithelial-mesenchymal transition (EMT) were induced by lentivirus transduction of SOX2 into SMMC-7721 cells, including the down-regulation of E-cadherin, and ZO-1, and the concomitant up-regulation of N-cadherin and Fibronectin. The overexpression of SOX2 in the HCC cell line promoted cell motility and invasion. Conclusion Our findings have uncovered a novel role for SOX2 in HCC metastasis, and provide a potential therapeutic target for HCC therapy. Key words: Carcinoma, hepatocellular; Sex determining region Y-box 2; Epithelial-mesenchymal transition; Proliferation; Invasion; Migration