Abstract: To investigate the effect of vitamin D receptor (VDR) in HepG2 cell proliferation and the significance of VDR in liver cancer, HepG2 cells were transfected with VDR gene-specific siRNA (small interfering RNA). The qPCR and WB results showed that compared with the control NC siRNA group, VDR siRNA-507 could significantly inhibit the mRNA and protein levels of VDR (P<0.05). The celltiter-Lumi luminescence, EDU staining and cell colony formation assay were employed to detect the effect of interference VDR on the proliferation of HepG2 cells. The results confirmed that interference with VDR could significantly promote the proliferation of HepG2 cells (P<0.01). The immunofluorescence and double luciferase activity assay were used to monitor the RBP4 expression during HepG2 cells growth process. However, interfering VDR had no effect on RBP4 expression level in HepG2. It was concluded that interference with VDR could promote HepG2 cells proliferation which was no relation with RBP4 level.

Key words: vitamin D receptor, HepG2 cell, small interfering RNA, cell multiplication, retinol binding protein 4