Since Gö6976 is a selective inhibitor of PKCα, PKCβ and PKCμ and Gö6983 a selective inhibitor of PKCα and PKCβ but not PKCμ [26, 27], we hypothesized that the specific inhibition of PKCμ, which is also known as PKD1 (protein kinase D1), would be responsible for the Gö6976-induced N- to E-cadherin switch and tumor reversion in metastatic melanoma cells. This evidence concerns the gene PRKD1 and metastatic melanoma.