MITF and melanoma: Similarly, in the BRAF; PTEN melanoma mouse model, when tumors are induced on the tail, which better mimics the melanoma transition from a radial to a vertical growth phase [59], the loss of differentiation markers (such as MITF) in a subset of epidermal melanoma cells, before the dermal invasion, was shown to be associated with ZEB1 activation, reinforcing the role of ZEB1 in this transition.