phs002448
Inhibition of CDK4/6 Promotes CD8 T cell memory
Inhibitors of Cyclin-Dependent Kinase 4 and 6 (CDK4/6) have been recently deployed for the treatment of advanced breast cancer. Despite their success, the mechanism of action of these drugs is unclear. In mice, treatment with a CDK4/6 inhibitor improve T cell memory responses and protect mice against tumor rechallenge. We aimed to identify the correlates of this finding in human subjects. In this study, blood was collected from 5 breast cancer patients before and during treatment with the CDK4/6 inhibitors abemaciclib or palbociclib. Blood was also collected from 2 breast cancer patients who did not receive a CDK4/6 inhibitor. Recently activated CD8 T cells (CD45RO+ CD45RA+) were sorted and subjected to single-cell RNA sequencing.