ATR and small cell lung carcinoma: We and others have shown that DDR components (CHK1, ATR, WEE1, PARP, ATM) are overexpressed in SCLC and that replication-stress-response inhibitors are active in preclinical models of SCLC (Byers and Rudin, 2015; Byers et al., 2012; Dammert et al., 2019; Sen et al., 2017a, 2017b, 2018; Taniguchi et al., 2020).