Abstract
BACKGROUND AND AIMS: Raf kinase inhibitor protein (RKIP) is an important member of the phosphatidylethanolamine-binding protein family. This study investigated the inhibitory effect of RKIP on the malignant biological behavior of liver cancer cells in vivo and in vitro. METHODS: An RKIP gene expression vector was constructed using the pcDNA3.1 vector and transfected into human hepatoma cell line HepG2 to overexpress the RKIP gene. Growth, proliferation, the cell cycle, apoptosis, migration, and invasion of the cell line were analyzed. For in vivo experiments, the vector was transfected into tumor tissue of hepatoma-bearing animals and then tumor growth was analyzed and compared with the control to assess its anti-tumor effect. RESULTS: Compared with the control group, cell growth in the RKIP gene transfection group (HEP-RKIP) was significantly slower. The average colony formation rate of the HEP-RKIP group was significantly lower than that of the other two groups (p < 0.05). The proportion of HEP-RKIP cells in G0/G1 phase was significantly higher than that of the control group (p < 0.05), while the proportion of cells in G2/M phase was significantly lower than that in the control group (p < 0.05). The apoptosis rate of HEP-RKIP cells was approximately 6.4%, which was significantly higher than that of the control group (p < 0.05). Migration of HEP-RKIP cells was significantly slower than that of the other two groups (p < 0.05). In an inhibition experiment of the liver tumor animal model, the tumor inhibition rate of the RKIP in vivo transfection group was significantly higher than that of each control group (p < 0.05). CONCLUSION: RKIP inhibits malignant biological behavior of liver cancer cells in vitro and has a tumor inhibitory effect in vivo, which may be a potential target for gene therapy of liver cancer.