Inhibition of Wnt signaling induces cell apoptosis and suppresses cell proliferation in cholangiocarcinoma cells.

The aim of the present study was to explore possible gene therapy for hilar cholangiocarcinoma by detecting the activation of the Wnt signaling pathway in 4 cholangiocarcinoma cell lines and inhibiting its expression by RNA interference (RNAi) targeting key factors of this pathway. The expression levels of the Wnt pathway-related factors, Wnt2, Wnt3, β-catenin and transcription factor 4, and its target genes, c-myc and cyclin D1, in 4 cholangiocarcinoma cell lines were detected by RT-PCR, western blotting and immunofluorescence microscopy. After transfection of siRNAs targeting Wnt2 and β-catenin into FRH0201 cells, the expression of the Wnt pathway-related factors and its target genes was again detected, and the cell cycle distribution, apoptosis and proliferation were analyzed by flow cytometry and MTT assay. Activation of the Wnt pathway and the expression of its target genes were detected in all 4 cell lines at various levels. After siRNA transfection, the expression of the target genes in the FRH0201 cells was significantly downregulated. In addition, the Wnt pathway was blocked, cell apoptosis was enhanced and cell proliferation was suppressed. In conclusion, the Wnt signaling pathway is activated in cholangiocarcinoma cells. RNAi technology targeting Wnt2 and β-catenin may be a possible gene therapy for hilar cholangiocarcinoma.