PPP1R1B and small cell lung carcinoma: Given that DARPP-32 isoforms (Figs. 4 and 5a) and ASCL1 (Fig. 5d) are both overexpressed in SCLC and ChIP-seq studies suggest ASCL1 may interact with the PPP1R1B promoter,32 we investigated whether ASCL1 regulates DARPP-32.