CDK4 and posterior cortical atrophy: In this setting, a study on CRPC and neuroendocrine PCa models has demonstrated that combination therapy with PARP inhibitors and CDK4/6 inhibitors resulted in synergistic suppression of the p-Rb1-E2F1 axis and induced apoptosis and suppressed neuroendocrine differentiation in PCa, paving the way for new trials testing this combination [22].