The epigenetic regulator Bmi1 is known to promote cellular proliferation through its control of cell cycle genes. However, researchers in the laboratory of KI faculty member Jacqueline Lees have found an unexpected role for Bmi1 in melanoma, where it does not drive proliferation. Instead, the authors of a recent study published in Genes & Development find that Bmi1 supports melanoma metastasis by turning on genes that help melanoma cells invade tissues and survive new environments. Moreover, they find that melanomas with high Bmi1 levels are resistant to BRAF inhibitors--drugs commonly administered as the BRAF gene is activated in 50% of early-stage melanomas.