SIK2 and melanoma: Fascinatingly, the in-vitro results were replicated in in-vivo research, demonstrating that fisetin greatly reduced tumor growth in 451Lu melanoma xenografts, which was connected to lower MITF levels.21, 55Furthermore, a different study showed that the mono-methyl analog of fisetin, 4 MF, is a potent SIK2 inhibitor and significantly increases melanogenesis in B16F10 melanoma cells.