ABSTRACT
Objective@#Abstract: Objective: To investigate the expression and significance of miR-138 and programmed cell death protein 1 (PD-1) in the patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). @*Methods@#A total of 30 patients with HBV-related HCC, 20 with HBV-related cirrhosis (LC) and 30 with chronic hepatitis B (CHB) were recruited from Jiaozuo People′s Hospital. The blood samples from all patients and the peritoneal effusion samples from HCC and LC patients were collected. The levels of miR-138 and soluble PD-1 (sPD-1) in blood and peritoneal effusion samples were detected by real-time PCR and ELISA, respectively. The expressions of PD-1 in T lymphocytes were measured with flow cytometry and western blot. The targeting effect of miR-138 on the 3′-non-coding region (3′-UTR) of PD-1 gene was verified by the dual-luciferase reporter gene system. @*Results@#The relative expression levels of miR-138 in the peritoneal effusion and plasma of HBV-related HCC patients were significantly lower than those in LC and CHB patients (P＜0.05). The serum sPD-1 levels and the expression levels of PD-1 in CD3 + T lymphocytes of HBV-related HCC patients were significantly higher than those in LC and CHB patients (P＜0.05). The relative expression levels of miR-138 were negatively correlated with serum sPD-1 levels and the expression levels of PD-1 in CD3 + T lymphocytes (P＜0.05). The dual-luciferase reporter gene system and western blot results demonstrated that there was a targeting relationship between miR-138 and the 3′-UTR of PD-1 gene. After miR-138 was transfected, the expression level of PD-1 was significantly down-regulated. @*Conclusion@#miR-138 participates in the development and progression of HBV-related HCC probably by targeting PD-1.