In small cell lung cancer, NOTCH inactivation leads to ASCL1-mediated upregulation of DARPP-32 and activation of AKT/ERK signaling [29] that is likely independent of the EGFR-ERBB3 axis, suggesting that DARPP-32 may promote tumor cell survival through multiple mechanisms. This evidence concerns the gene PPP1R1B and small cell lung carcinoma.