GSK3B and colorectal cancer: Of note, in the Netrin‐1 conditional knockout mouse model, we observed significant dopaminergic neuronal loss, accompanied by increased α‐synuclein hyperphosphorylation at Ser129 and elevated levels of the truncated form of deleted in colorectal cancer (DCC) generated by activated caspase‐3, a marked depletion of DRD2 expression, and hyperphosphorylation of GSK3β at Tyr216.