Moreover, while caspase 8 protein levels were almost undetectable in human SCLC cell lines as compared to human NSCLC cell lines (Supplementary Fig. 1d), caspase 8 protein was expressed at comparable levels between murine NSCLC and SCLC cell lines (Supplementary Fig. 1e), indicating that the RP mouse model retains high expression levels of caspase 8. This evidence concerns the gene CASP8 and non-small cell lung carcinoma.