Interestingly, in multiple myeloma patients, IMiDs increase the production of IFN-γ (an inhibitor of melanogenesis) from T cells, and IMiDs downregulate VEGF, bFGF, and granulocyte macrophage-colony stimulating factor (GM-CSF), all of which have promotive effects on melanogenesis 193, 201, 209-213. This evidence concerns the gene CSF2 and plasma cell myeloma.