Sinensetin Inhibits Angiogenesis in Lung Adenocarcinoma via the miR-374c-5p/VEGF-A/VEGFR-2/AKT Axis.

Sinensetin is a product isolated from Orthosiphon aristatus, and its antitumor activities have been well established. This study focused on the role and mechanism of sinensetin in lung adenocarcinoma (LUAD). LUAD cells were treated with various concentrations of sinensetin. The proliferation, migration, invasion, and angiogenesis of LUAD cells were detected using colony formation, transwell, and tube formation assays, respectively. The protein levels of VEGF-A, VEGFR-2, and phosphorylated AKT (ser473) were measured by western blotting. The targeted relationship between VEGF-A and miR-374c-5p was verified by luciferase reporter assay. BALB/c nude mice inoculated with A549 cells were treated with sinensetin (40 mg/kg/day) by gavage for 21 days to investigate the effect of sinensetin on tumor growth and angiogenesis in vivo. We found that sinensetin reduced proliferation, migration, invasion, angiogenesis, and cancer stem characteristics of LUAD cells. Sinensetin also suppressed LUAD tumor growth and angiogenesis in vivo. Sinensetin downregulated VEGF-A expression in LUAD cells by enhancing miR-374c-5p expression. MiR-374c-5p inhibited the VEGF-A/VEGFR-2/AKT pathway in LUAD cells. The antitumor effect of sinensetin was reversed by overexpression of VEGF-A or inhibition of miR-374c-5p. Overall, sinensetin upregulates miR-374c-5p to inhibit the VEGF-A/VEGFR-2/AKT pathway, thereby exerting antitumor effect on LUAD.