NOTCH1 and small cell lung carcinoma: Given our data indicating a specific association between NOTCH1 expression, but not NOTCH2 expression, and ICB survival in SCLC, we next sought to elucidate potential differences between NOTCH1 and NOTCH2, as these Notch paralogs have been previously reported to have similar functions in SCLC as tumor suppressors (23) and drivers of NE to non-NE transdifferentiation (24, 25).