FZD4 and melanoma: We therefore chose to focus on FZD4, FZD6, and FZD8 in the further experiments and treated the LECs with either control siRNA or siRNAs targeting the FZD4, FZD6, or FZD8 gene for 24 hours before the start of the 48-hour coculture with WM852 melanoma cells, followed by sorting and functional assays.