In conclusion, the loss of AATK via epigenetic silencing in various cancers drives uncontrolled cell growth by interfering with a hypothesized signaling cascade including TP53 phosphorylation and subsequent reduction in expression of the key cell cycle regulators CCND1 and WEE1. Loss of AATK expression is observed in multiple tumor entities and correlates with reduced patient survival. This evidence concerns the gene CCND1 and cancer.