Notch signaling plays a key role in embryonic vascular development and angiogenesis. The authors aimed to study the prognostic role of the angiogenesis‐related Notch ligands and receptors and investigate the prognostic impact of the coexpression of vascular endothelial growth factor‐A (VEGF‐A) and Notch signaling.

Tumor tissue samples from 335 resected patients with stage I to IIIA nonsmall cell lung cancer (NSCLC) were obtained, and tissue microarrays were constructed from duplicate cores of tumor cells and tumor‐related stroma from each specimen. Immunohistochemistry was used to evaluate the expression of the molecular markers Notch‐1, Notch‐4, Delta‐like ligand 4 (DLL4), and Jagged‐1.

There were 191 squamous cell carcinomas (SCCs), 113 adenocarcinomas (ACs), and 31 large cell carcinomas. In AC, low tumor cell Delta‐like ligand 4 expression was an independent negative prognostic factor (hazard ratio [HR], 2.9; 95% confidence interval [CI], 1.4‐6.3 [P = .006]), whereas high tumor cell Notch‐1 expression was an independent negative prognostic factor (HR, 2.2; 95% CI, 1.2‐4.1 [P<.001]). In SCC, low stromal Delta‐like ligand 4 expression was an independent indicator of poor prognosis (HR, 3.3; 95% CI, 1.8‐6.1 [P<.001]). The coexpression of Notch‐1 and VEGF‐A had a significant prognostic impact (P<.001). For Notch‐1 and VEGF‐A, low/low (n = 142) versus high/high (n = 35) expression resulted in 5‐year survival rates of 69% and 32%, respectively.

Delta‐like ligand 4 and Notch‐1 are independent prognostic factors in NSCLC, but have diverse impacts in SCC and AC. The coexpression of tumor cell Notch‐1/VEGF‐A has a major impact on survival. Cancer 2010. © 2010 American Cancer Society.