MAP2K1 and melanoma: It has been shown that silymarin induces cell cycle arrest and inhibits the growth of human melanoma SK-MEL-5 and SK-MEL-28 cells in the G1 phase by blocking MEK1/2-RSK2 signaling, leading to a decrease in the activation of various transcriptional regulators of proliferation genes in melanoma, such as nuclear factor-kappaB, activator protein-1, and signal transduction and transcriptional activator 3.