Accordingly, we performed serial selection in immunodeficient NSG (NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ) mice using two SCLC cell lines (H1836 and H82) and a patient-derived xenograft model (PDX Lx773I) (Fig. 1b, Supplementary Fig. 1c). Here, CTSG is linked to small cell lung carcinoma.