USP39 and neoplasm: In the A375 and M14 cell lines constructed by knocking down USP39, the researchers observed that melanoma cell proliferation was suppressed, and cell cycle progression was arrested at the G0/G1 phase, while the growth of tumors in the nude mice transplantation tumor model was also inhibited in vivo, suggesting that the inhibition of USP39 expression can alleviate the malignant progression of melanoma to some extent.