POU3F2 and melanoma: BRN2 bound to a fragment (−77 to −20) of the MITF promoter in vitro, but not when the putative BRN2 binding site was mutated (data not shown) and chromatin immunoprecipitation (ChIP) assays showed that endogenous BRN2 binds to the proximal region of the MITF promoter in melanoma cells (Figure 2E).