Similarly, shRNA-mediated DARPP-32 protein knockdown in H1048 cells (Fig. 1f and Supplementary Fig. 1b: right panel) resulted in a reduced cellular growth rate (Supplementary Fig. 2d) and fewer viable cells (Supplementary Fig. 3d) relative to corresponding LacZ shRNA transduced control SCLC cells. Here, PPP1R1B is linked to small cell lung carcinoma.