Abstract
Angiogenesis is a rare event that is tightly controlled under normal physiological conditions, because normal cells secrete only low levels of positive regulators and high levels of negative regulators of angiogenesis.
Angiogenesis plays an important role not only in wound healing but also in cancer development. Recently, the mechanism of cancer progression or metastasis has been shown to be associated with angiogenesis. Vascular endothelial growth factor (VEGF) has been identified as one of the factors that increases permeability and endothelial cell proliferation. We previously reported VEGF expresstion was high in 43% of head and neck squamous cell carcinomas (HNSCCs), and high VEGF expression was significantly correlated with lymph node spread. Furthermore, prognosis was significantly worse in patients with high expression compared to that in those with low expression. Endostatin which is isolated as an endogenous angiogenic inhibitor was overexpressed in 37%. Endostatin expression correlated with tumor size, p53 expression and Ki-67 expression. Such angiogenic inhibitors may be available for cancer treatment.
