Although both ASCL1 and NEUROD1 bind DNA sequences containing similar E-box motifs, these TFs preferentially bind distinct E-box motifs, and regulate mostly distinct genes in the SCLC cell lines driven by each TF, due, at least in part, to the cooperation of cell line- or cell lineage-specific co-factors29. The gene discussed is NEUROD1; the disease is small cell lung carcinoma.