MiR-125b-5p Inhibits Angiogenesis by Targeting VEGFA to Improve the Efficacy of Transcatheter Arterial Chemoembolization in the Treatment of Hepatocellular Carcinoma

Abstract

Background: Hepatocellular carcinoma (HCC) is a kind of multi-vessel tumor with high morbidity and mortality. Anti-angiogenesis is a promising treatment for HCC. In recent years, transcatheter arterial chemoembolization (TACE) is a typical non-surgical anti-angiogenic therapy for HCC. This study aimed to explore the effect and mechanism of miR-125b-5p on TACE for treating HCC. Methods: Twenty patients with HCC received surgery after TACE and were subjected to tumor tissues collection. Twenty patients with HCC underwent surgery only and tumor tissues and adjacent tissues were collected. Additionally, serum samples were obtained from patients before and after TACE, and from patients with remission or recurrence after TACE treatment. Knockdown or overexpression of miR-125b-5p and overexpression of vascular endothelial growth factor A (VEGFA) were carried out in human HCC cell line (HCCLM3). Real time quantitative PCR (qRT-PCR) was employed to measure the expression of miR-125b-5p and VEGFA. Cell proliferation, viability, and tube-forming ability of HCCLM3 cells were detected using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation, and tube formation assay. Further, a dual luciferase reporter assay was carried out to determine the relationship between miR-125b-5p and VEGFA. Western blot was adopted to test the level of VEGFA in the tissues and MEK/ERK signaling pathway-related proteins in the cells were measured. Results: MiR-125b-5p expression in the tumor tissues of patients with HCC receiving TACE and surgery was notably increased relative to those of patients receiving surgery only. The expression of miR-125b-5p mounted obviously in the serum after TACE (before TACE vs. after TACE), but showed a marked decline in the serum of patients with recurrence after TACE treatment (remission vs. recurrence). At cellular level, miR-125b-5p expression was noticeably reduced in HCC cell line, and its overexpression inhibited HCC cell proliferation and angiogenesis as well as the activation of the mitogen-activated protein kinase kinase (MEK1/2)-extracellular signal-regulated kinase (ERK) signaling pathway. Moreover, there was a targeting relationship between miR-125b-5p and VEGFA, and VEGFA expression was significantly decreased in the tumor tissues of patients after TACE treatment compared with the patients who received surgery alone. VEGFA could reverse the inhibitory effect of the overexpression of miR-125b-5p on HCC cells. Conclusions: MiR-125b-5p targeted and inhibited VEGFA expression to affect angiogenesis, and it affected cell proliferation and viability by inhibiting the MEK1/2-ERK1/2 signaling pathway, thereby improving the efficacy of TACE in the treatment of HCC.