Ca2+-signaling of human melanoma is in the focus of intensive research since the identification of the role of WNT-signaling in melanomagenesis. Genomic and functional studies pointed to the important role of various Ca2+ channels in melanoma, but these data were contradictory. In the present study we clearly demonstrate, in a number of different ways including microarray analysis, DNA sequencing and immunocytochemistry, that various human melanoma cell lines and melanoma tissues overexpress ryanodine receptor type 2 (RyR2) and express P2X7 channel proteins as compared to melanocytes. These channels, although retain some of their usual characteristics and pharmacological properties, display unique features in melanoma cells, including a functional interaction between the two molecules. Unlike P2X7, RyR2 does not function as a calcium channel. On the other hand, the P2X7 receptor has an antiapoptotic function in melanoma cells, since ATP-activation suppresses induced apoptosis, while knock down of the gene expression significantly enhances that. © 2007 Wiley-Liss, Inc.