Accordingly, forced expression of CYP27A1 only in melanoma cells (Fig. 4F–G) increased cellular 27HC content (Fig. 4H), caused vemurafenib resistance (Fig. 4I, J), and promoted melanoma spheroid propagation (Fig. 4K, L) in both A375 and A2058 melanoma cells, independent of DHCR24 induction. This evidence concerns the gene DHCR24 and melanoma.