Inverse correlation between apoptotic (Fas ligand, caspase-3) and angiogenic factors (VEGF, microvessel density) in squamous cell lung carcinomas.

In order to explore whether apoptosis is associated with angiogenesis in lung cancer, immunohistochemistry was employed to determine the pro-apoptotic factors Fas ligand (FasL) and caspase-3 (Cas-3) in 70 squamous cell lung carcinomas. Furthermore, the vascular endothelial growth factor (VEGF) and the microvessel density (MVD) were analyzed. The comparison between MVD and the pro-apoptotic factors demonstrated that the apoptotic factors are inversely related to MVD (Cas-3: p = 0.011, FasL: not significant). In order to confirm this result, FasL and Cas-3 were also compared with the expression of VEGF. Again, an inverse correlation between VEGF and the pro-apoptotic factors was found (Cas-3: p = 0.019, FasL: p = 0.008). The inverse correlation between angiogenesis and apoptosis may be explained by the activation of pro-apoptotic and anti-angiogenic factors caused by hypoxia.