Silencing of hsa_circ_0101145 reverses the epithelial-mesenchymal transition in hepatocellular carcinoma via regulation of the miR-548c-3p/LAMC2 axis

Abstract

Hepatocellular carcinoma (HCC) is a primary cause of cancer-related deaths globally. While there have been advancements in HCC treatment and diagnosis, incidence and mortality rates continue to rise. One study found that circular RNAs functioned as competing endogenous RNAs, and constructed a gene-based nomogram to estimate overall survival of HCC patients. Previous studies using high-throughput sequencing suggested that hsa_circ_0101145 is abnormally expressed in HCC, but the underlying mechanism is unknown. We performed RT-qPCR to determine hsa_circ_0101145 and miR-548c-3p expression in HCC tissues. We used fluorescence in situ hybridization (FISH) to detect hsa_circ_0101145 expression and hsa_circ_0101145 subcellular localization in HCC tissues. hsa_circ_0101145 expression in HCC cells was selectively regulated. We determined LAMC2 and EMT mRNA and protein levels by RT-qPCR and western blotting analysis, respectively. We employed flow cytometry, and CCK8, Transwell, and wound healing assays to monitor the cell cycle, cell proliferation, invasion, and migration, respectively. We employed dual-luciferase reporter and RNA pulldown assays to verify the relationship among hsa_circ_0101145, miR-548c-3p, and LAMC2. We examined the effects of hsa_circ_0101145 on HCC cell metastasis and proliferation in vivo using a subcutaneous xenograft model as well as intravenous tail injection of nude mice. The data demonstrated that hsa_circ_0101145 was significantly upregulated in both HCC tissues and cell lines. High hsa_circ_0101145 expression was correlated with aggressive HCC phenotypes. Downregulation of hsa_circ_0101145 suppressed HCC proliferation as well as metastasis by targeting the miR-548c-3p/LAMC2 axis, which was examined using luciferase reporter and RNA pulldown assays. Silencing of hsa_circ_0101145 suppressed the epithelial-mesenchymal transition in HCC. Downregulation of miR-548c-3p or overexpression of LAMC2 restored migration and proliferation abilities of HCC cells following hsa_circ_0101145 silencing. LAMC2 overexpression reversed miR-548c-3p-induced cell migration and growth inhibition in vitro. In summary, the findings illustrated that hsa_circ_0101145 silencing suppressed HCC progression by functioning as an miR-548c-3p sponge to enhance LAMC2 expression. Therefore, hsa_circ_0101145 could be an HCC treatment target.