The Effects And Underlying Mechanisms Of Chemokine Receptor CX3CR1 On Human Hepatocellular Carcinoma Cells

Objective:To investigate the effect and underlying mechanisms of chemokine CX3C receptor 1 (CX3CR1) on human hepatocellular carcinoma cells and lay a theoretical foundation for clinical therapy of human hepatocellular carcinoma.Methods:In vitro, hepatocellular carcinoma Huh7 and HepG2 cells were transfected with the recombinant adenovirus AdR-si-CX3CR1 targeting and silencing CX3CR1 gene. Then the expression of CX3CR1 was detected by reverse RT-PCR and Western blot. The proliferation, apoptosis, migration and invasion of Huh7 and HepG2 cells were tested by MTT, FCM, wound-healing and Transwell assay, respectively. The expression of p-Akt which was related to PI3K-Akt signal pathway and p-ERK1/2 which was related to ERK1/2 MAPK signal pathway were detected by Western blot. Meanwhile, HepG2 cells transfected with AdR-si-CX3CR1 were treated with different concentrations of PI3K inhibitor LY294002, then the expression of p-Akt and cell invasion ability induced by CX3CR1 were detected by Western blot and Transwell assay, respectively. In vivo, the effect of HepG2 cells transfected with AdR-si-CX3CR1 on tumor formation and metastasis were tested by tumorigenicity assays in nude mice.Results:After AdR-si-CX3CRl was stably transfected into Huh7 and HepG2 cells in vitro, the expression of CX3CR1 was significantly inhibited, cell proliferation, migration and invasion abilities increased significantly, but apoptosis rate decreased significantly. When the expression of CX3CR1 was silenced, the levels of p-Akt in HepG2 cells increased, but no obvious difference was found between the levels of p-ERK1/2. And LY294002 could reverse CX3CR1-induced phosphorylation of Akt and invasion of HepG2 cells effectively. In vivo, expression silencing of CX3CR1 promoted tumor formation and metastasis of HepG2 cells by tumorigenicity assays in nude mice.Conclusions:CX3CR1 gene silencing could promote proliferation, migration and invasion of hepatocellular carcinoma Huh7 and HepG2 cells, and could suppress their apoptosis in vitro, and also promoted tumor formation and metastasis in vivo. Activation of PI3K-Akt signaling pathway may be involved in this process.