Long Non-coding RNA LINC00342 Promotes the Proliferation, Invasion, and Migration of Primary Hepatocellular Carcinoma Cells by Regulating the Expression of miRNA-19a-3p, miRNA-545-5p, and miRNA-203a-3p.

Abstract

This study aimed to investigate the role of the long non-coding RNA (lncRNA) LINC00342-207 (LINC00342) in the development and progression of primary hepatocellular carcinoma (HCC). Forty-two surgically resected HCC tissues and corresponding paracancerous tissues were collected from October 2019 to December 2020 and examined for lncRNA LINC00342, microRNA (miR)-19a-3p, miR-545-5p, miR-203a-3p, cell cycle protein D1 (CyclinD1/CCND1), murine double minute 2 (MDM2), and fibroblast growth factor 2 (FGF2) expression. The disease-free survival and overall survival of patients with HCC were followed up. HCC cell lines and the normal hepatocyte cell line HL-7702 were cultured and the expression level of LINC00342 was measured. HepG2 cells were transfected with LINC00342 siRNA, LINC00342 overexpression plasmid, miR-19a-3p mimics and their corresponding suppressors, miR-545-5p mimics and their corresponding suppressors, and miR-203a-3p mimics and their corresponding suppressors. The proliferation, apoptosis, migration, and invasion of HepG2 cells were detected. Stably transfected HepG2 cells were inoculated into the left axilla of male BALB/c nude mice, and the volume and quality of transplanted tumors as well as the expression levels of LINC00342, miR-19a-3p, miR-545-5p, miR-203a-3p, CCND1, MDM2, and FGF2 were examined. LINC00342 played an oncogenic role in HCC and exhibited inhibitory effects on proliferation, migration, and invasion, and promoted the apoptosis of HepG2 cells. Moreover, it inhibited the growth of transplanted tumors in vivo in mice. Mechanistically, the oncogenic effect of LINC00342 was associated with the targeted regulation of the miR-19a-3p/CCND1, miR-545-5p/MDM2, and miR-203a-3p/FGF2 axes.