Proliferation and Migration of Lung Cancer Could be Inhibited by Oxymatrine through the Regulation for miR-520/VEGF.

Recent evidence suggests that Oxymatrine (OMT) has excellent effects in anticancer. The mechanism, however, remains unclear. In the present study, we investigated the potential mechanism of OMT against cancer. The differential expression of miRNA was screened by miRNA array. The expression of miRNA-520 and VEGF in lung cancer was assayed by real-time PCR, Western blot and immunohistochemistry, respectively. The direct interaction between miRNA-520 and VEGF was assayed by luciferase activity assay and their roles in lung cancer proliferation, invasion and migration were analyzed in vivo and in vitro. We found that miR-520 was markedly down-regulated and VEGF was markedly upregulated in lung cancer tissues compared with adjacent normal tissues, which had significant negative correlation. Dual-luciferase assays confirmed that miR-520 directly targeting VEGF by binding to its upstream promoter region. Through in vitro and in vivo experiments, we found that different doses of OMT could up-regulate miR-520, selectively inhibit VEGF and thus inhibit the proliferation and migration of lung cancer. Our findings indicate that OMT inhibited cancer progression and metastasis by upregulation of miR-520 and downregulation of VEGF, which provide new support for OMT may be as a novel anticancer drug for the treatment of lung cancer in the future.