In this study we show that pharmacological inhibition of OC2 with CSRM617, a OC2 inhibitor developed by medicinal chemists in our group (Rotinen et al. 2018) effectively suppresses the growth of human and mouse cell lines representative of the ASCL1 and NEUROD1 SCLC subtypes. This evidence concerns the gene ONECUT2 and small cell lung carcinoma.