Thanks to Aguirre-Portolés C and collaborators, an alternative testosterone pathway has been identified for the first time: studying 98 human melanocytic lesions (nevus, primary, and metastatic melanoma from both males and females) they reported that testosterone promoted melanoma proliferation through activation of ZIP9 (SLC39A9), a zinc transporter that is widely expressed in human melanoma, but not yet targeted by available therapeutics [47] (Figure 1). This evidence concerns the gene SLC39A9 and metastatic melanoma.