KYNU and melanoma: We determined whether the expression pattern of KYNU in melanocyte-derived heterotypic tumor cells is the same as that in epidermal keratinocytes, whether the effects of KYNU on proliferation, differentiation, and metabolism are involved in the process of malignant transformation in melanoma, such as the process of melanogenesis, and whether mutations in the active site of the KYNU enzyme can serve as screening targets in the pathogenesis of melanoma.