CDK4 and cancer: Agents shown to increase cancer cell antigen presentation include hydroxychloroquine (by autophagy inhibition) (Yamamoto et al., 2020), poly(I:C) (by NF-κB activation downstream of dsRNA sensing) (Kalbasi et al., 2020), SMAC mimetics (by NF-κB activation) (Gu et al., 2021), CDK4/6 inhibitors (by activation of endogenous genomic retroviral elements) (Goel et al., 2017), and others.