The BCL-2, BCL-XL inhibitor, ABT-263, is one of the few therapies to date to exhibit marked efficacy against SCLC in laboratory studies21, and although recent results from clinical trials with single-agent ABT-263 demonstrated responses in only a minority of SCLC patients22, combinations with this agent are being explored23. This evidence concerns the gene BCL2L1 and small cell lung carcinoma.