BMI1 and melanoma: Apart from altered DNA-methylation patterns and microRNA deregulation, histone modifying enzymes such as histone deacetylases (HDAC) and polycomb repressive complex (PRC) members EZH2, JARID2, and BMI1, have been implicated in melanoma growth, epithelial-mesenchymal transition (EMT), and metastasis (reviewed in [4–6]).