Abstract
Cyclin-dependent kinase -4 and -6 (CDK4/6) inhibitors are currently being assessed in clinical trials for the treatment of many cancers including melanoma. While investigating the mechanisms of CDK4/6 inhibitor resistance in melanoma, we uncovered a mechanism of action of these inhibitors in regulating the expression of both the mouse double minute 4 (MDM4) oncogene and tumor protein p53 (TP53).