MITF and melanoma: NURF components are expressed in all tested melanoma cell lines and shRNA-mediated BPTF silencing showed its essential role in a variety of MITF-expressing melanoma cell lines, including 501Mel, MNT1, SK-Mel-28, and 888-Mel as well as the MITF-negative 1205Lu cell line where it must act independently of MITF.