CDKN1A and melanoma: Won et al. (2012) discovered that tanshinone IIA induced G1 stagnation by activating p53/p21 signaling and inhibiting androgen receptors in LNCaP cells. Furthermore, tanshinone IIA induced the cell cycle in prostate cancer to stall at the G1 phase by lowering cyclin D1, CDK2, and CDK4. Another research found that treatment with cryptotanshinone could potentially enhance P21 and P53 expression in melanoma (A375 cells), and reduce Rb phosphorylation, CDK2 activation, and cyclin A2 expression (Zanre et al., 2022).