TYR and melanoma: Indeed, diethylstilbestrol, which is a diphenolic component, is able to enhance melanin synthesis in B16 mouse melanoma cells by activation of the cyclic AMP-protein kinase A pathway and upregulation of expression and activity of the melanogenesis-related enzyme tyrosinase − + and microphthalmia-associated transcription factor, a trans-acting factor that regulates the gene transcription of tyrosinase [30].