RAGE Expression And The Effects Of RAGE On Invasiveness And Metastases In Human Hepatocellular Carcinoma Cell Lines

OBJECTIVE To investigate the expression of the receptor for advanced glycation end products(RAGE) in human hepatocellular carcinoma cell lines with distinct metastatic potentials and its effects on the viability of cell proliferation, invasion or metastasis of human hepatocellular carcinoma cells, and to initially explore the role of NF-κB signaling pathway in this process.METHODS RT-PCR and Western blot analysis were employed respectively to detect the expression of RAGE mRNA and protein in three human hepatocellular carcinoma cell lines with unique metastatic characteristics, Hep3B, MHCC97L and HCCLM3. ELISA was used to detect the level of soluble form of RAGE(sRAGE) in the supernatant of these cells. A siRNA sequence targeted at RAGE gene was transfected into the human hepatocellular carcinoma cell line HCCLM3, which possessed the highest metastatic potential. And HCCLM3cells were treated in vitro with exogenous RAGE antibody or recombinant human RAGE protein(sRAGE). Cell viability was detected by MTT assay and typan blue exclusion method. Invasive ability of HCCLM3cells was detected with transwell chamber. Wound healing assay was employed to show their metastatic abilities. RT-PCR and Western blot were used to detect the effects on expression of NF-κB subunits P50and P65. RESULTS1. The expression levels of RAGE mRNA and protein were higher in HCCLM3cells(with higher metastatic potential) than MHCC97L cells(with lower metastatic potential) or Hep3B cells(with lowest metastatic potential). The level of sRAGE in the supernatant of these there cell lines negatively related to their metastatic potentials.2. RAGE knockdown by RAGE siRNA, inhibition of RAGE signaling pathway by interference with RAGE antibody or exogenous sRAGE protein reduced the cell viability, invasion and migration ability of HCCLM3cells, and decreased their expression levels of NF-κB subunits P50and P65.CONCLUSIONS The expression of RAGE in human hepatocellular carcinoma cell lines is relative to their metastatic characteristics. RAGE involved in the progression of hepatocellular carcinoma in vitro by promoting cell viability, invasiveness and metastases, and NF-κB signaling pathway may play a significant role in this process.