Thus MITF is akin to TGFβ, which, is also either a tumour promoter or a tumour suppressor [28] and we propose that MITF expression/activity must be carefully regulated in melanoma cells to ensure that the levels are not so low as to cause cell death but equally, not so high as to cause cell cycle arrest and differentiation (Figure 6). The gene discussed is TGFB1; the disease is melanoma.