RB1 and small cell lung carcinoma: These two cell populations clustered separately by RNA-seq analysis and in a manner similar to the Hes1low/GFPneg and Hes1high/GFPhigh SCLC cell lines, respectively, with complete deletion of p53, Rb and p130 alleles confirmed by PCR on genomic DNA, further validating the isolation protocol (Supplementary Fig. 6c–e).