Factors influencing tissue concentration of vascular endothelial growth factor in colorectal carcinoma

OBJECTIVE: Vascular endothelial growth factor (VEGF) promotes proliferation of various tumor cells by stimulating angiogenesis. Experimentally, hypoxi a and energy depletion are known to induce angiogenesis by increasing VEGF expression. We investigated whether factors reflecting the general conditio n of the patients influence the tissue concentration of VEGF in colorectal carcinoma. METHODS: Tissue concentrations of VEGF in 81 colorectal carcinomas, 81 norm al mucosas, and 30 colonic adenomas were determined. The expressions of VEG F and its receptor in cancer tissue were evaluated immunohistochemically. F or the assessment of the general preoperative condition of the patients, th e nutritional status was evaluated and arterial blood gas was analyzed. RESULTS: The mean concentration of VEGF in the cancer tissue was significan tly higher than that in the normal colonic mucosa and colonic adenoma. Tumo r size, histological grade, serum cholinesterase, and arterial level of PO, were the independent factors that influenced the tissue concentration of V EGF in colorectal cancer. Immunohistochemically, the VEGF-positive cancer t ended to have an increased expression of VEGF receptor, kinase insert domai n-containing receptor (KDR). In patients with positive KDR in the tumor, th e arterial levels of PO2 and O-2 saturation were significantly lower than t hose in patients without its expression. CONCLUSION: Tissue content of VEGF or expression of KDR in colorectal carci noma may be associated with disease status, including nutritional status, s ystemic oxygenation, and tumor progression. The systemic-local regulating m echanism of VEGF or KDR may play an important role in the constant growth o f tumor cells, especially in wasted colorectal cancer patients. (C) 2000 by Am. Cell. of Gastroenterology.