Growth index is independent of microvessel density in non-small-cell lung carcinomas

Abstract

Induction of angiogenesis is essential for carcinogenesis and facilitates the processes of tumor development and metastasis. Vascular endothelial growth factor (VEGF) is an important angiogenic regulator under physiologic and pathologic conditions. To elucidate the role of angiogenesis in malignant growth, we evaluated angiogenesis and VEGF expression in a panel of 68 non-small-cell lung carcinomas (NSCLCs) and examined their relation with the kinetic parameters, ploidy, and p53 protein status, which have been analyzed previously. Angiogenesis was estimated as microvascular density (MVD) of the tumor area by CD31 immunodetection. Expression of VEGF was also immunohistochemically evaluated. All possible associations were assessed through a series of statistical methods. The mean MVD value was 39 microvessels/mm(2), and high VEGF immunoreactivity was observed in all specimens, with a mean percentage of positive cells of 73%. The relation between MVD and VEGF expression was not statistically significant (P = 0.065). No association was observed between MVD or VEGF levels with the proliferation index, apoptotic index, tumor ploidy status, p53 expression, and overall survival. We conclude that in a subset of NSCLCs, angiogenesis may be associated with VEGF, but other factors also participate in this process. Angiogenesis and growth (proliferation and apoptosis) are independent and probably differentially operated procedures, with only growth partially controlled by p53 protein expression.