MCL1 and small cell lung carcinoma: Based on these dependencies, we divided SCLC cell lines into different categories; 1) primarily dependent on BCL-XL (such as H1963), 2) mainly dependent on BCL-2 (such as H889), 3) mostly dependent on MCL-1 (such as H209), 4) BCL-XL and BCL-2 co-dependent (such as H1059), 5) BCL-XL and MCL-1 co-dependent (such as H378), and 6) BCL-XL, BCL-2, and MCL-1 dependent (such as H211) (Fig. 2a).