PPP1R1B and breast cancer: Additionally, the downstream proteins of PPP1R1B have been reported to be overexpressed in numerous cancers, such as oesophageal, gastric, colon, prostate, and breast cancers.17 This gene has an alias called DARPP32, which is a dopamine and cyclic AMP‐regulated phosphoprotein.18 The phosphorylation or dephosphorylation of DARPP32 induced by cAMP signalling is still disputed.