Beyond the Cell Cycle: Enhancing the Immune Surveillance of Tumors Via CDK4/6 Inhibition

Inhibitors of the cyclin-dependent kinases 4 and 6 (CDK4/6) were originally designed to block proliferation and cell cycle progression of cancer cells in which the activity of these kinases is dysregulated. CDK4/6 inhibitors have already been FDA approved for the treatment of estrogen receptor (ER)-positive breast cancer and are being tested in numerous other cancer types. However, several recent studies have identified novel effects of CDK4/6 inhibitors on tumor growth, most notably an indirect effect resulting fromthe activation of immune surveillance. This Perspective discusses these recent observations, including the effects that CDK4/6 inhibitors may have on immune cells themselves. It is likely that CDK4/6 inhibitors will have a broader impact than their expected induction of cell cycle arrest in the treatment of human cancers. . (C) 2018 AACR.