CDK4 and Familial prostate cancer: We anticipate that a better understanding of the mechanisms of intrinsic and acquired resistance to CDK4/6 inhibitors will lead to the development of improved therapeutic strategies that will ultimately benefit patients with prostate cancer, either by refining the role of the CDK4/6 inhibitors in this patient population or by informing the development of new cell cycle inhibitors and novel combination therapies with inhibitors of other interconnected pathways.