lncRNA GABPB1 intronic transcript 1 upregulates pigment epithelium-derived factor via miR-93 to suppress cell proliferation in hepatocellular carcinoma

Liver cancer ranks in the top 10 most common malignancies for both mortality rate and incidence worldwide. Hepatocellular carcinoma (HCC) is the most common subtype of liver cancer. It has been reported that long non-coding RNA GABPB1 intronic transcript 1 (IT1) is downregulated in lung cancer and predicts poor survival. However, its role in live cancer remains unclear. Therefore, the present study aimed to investigate the role of GABPB1-IT1 in HCC. A total of 64 patients with HCC (40 males and 24 females; range, 43–67 years old; mean age=55.1±5.1 years) were enrolled at the 96604 Military Hospital of the Chinese People's Liberation Army between May 2012 and May 2014. The expression levels of GABPB1-IT1 and microRNA (miR)-93 in tumor and adjacent normal tissues were measured using quantitative PCR. A dual luciferase activity assay was performed to analyze the interaction between miR-93 and GABPB1-IT1. A Cell Counting Kit-8 assay was used to analyze the effect of miR transfection on the proliferation of SNU-398 cells. It was demonstrated that GABPB1-IT1 can interact with miR-93 in HCC cells, while overexpression of GABPB1-IT1 and miR-93 in HCC cells did not affect the expression of each other. GABPB1-IT1 was downregulated in HCC tissues compared with paired non-tumor tissues and predicted poor survival. Notably, overexpression of GABPB1-IT1 in HCC cells led to upregulation of pigment epithelium-derived factor (PEDF), a target of miR-93. In addition, overexpression of GABPB1-IT1 reduced the enhancing effects of miR-93 on HCC cell proliferation. Therefore, GABPB1-IT1 may upregulate PEDF through miR-93 to suppress cell proliferation in HCC.