The examples include cisplatin, which can impair the enzymatic functions of PTP1B [157]; vemurafenib, which was licensed for the treatment of non-resectable metastasized melanoma in humans [158], and based on a study with colorectal cancer lines HT29 and HCT116 it was also found to down-modulate the phosphatases (including PTP1B) serving as aggressiveness mediators in this type of cancer [159]; as well as ethacrynic acid, which restrained the growth of DU145 prostate carcinoma cells in xenografted mice by modulation of the PTP1B, leading to the inhibition of STAT3 activity [160]. This evidence concerns the gene PTPN1 and melanoma.