PPP1R1B and small cell lung carcinoma: In line with the previous study,48 we observed that overexpression of DARPP-32 and t-DARPP proteins protects SCLC cells from TRAIL-induced apoptosis based on our immunoblotting results showing reduced caspase-3 and PARP-I cleavage in TRAIL-treated DMS-53 cells overexpressing DARPP-32 or t-DARPP relative to LacZ control cells (Supplementary Fig. 4).