BACKGROUND & AIMS: Recent studies have shown that cyclooxygenase (COX)-2 and its products, prostaglandins (PGs), may be involved in colorectal carcinogenesis. The aim of this study was to determine whether COX-2 expression and PGE(2) production correlate with microvessel density, vascular endothelial growth factor (VEGF) expression, and tumor metastasis in human colorectal cancer. METHODS: Tumor samples and adjacent normal mucosa were obtained from 31 surgical specimens. Immunohistochemical expression of COX-2, VEGF, and CD31 was analyzed on paraffin-embedded tissue sections. COX-2 and COX-1 proteins were determined by Western blot analysis. COX-2 and VEGF messenger RNA expressions were evaluated using Northern blot analysis. PGE(2) production was determined by specific radioimmunoassay. RESULTS: The immunohistochemical expressions of both COX-2 and VEGF were significantly correlated with microvessel density (P = 0.02 and P = 0.002, respectively). A significant correlation was found between COX-2 and VEGF expression (P = 0.004). Western analysis confirmed the up-regulation of COX-2 protein expression. COX-2 and VEGF genes were overexpressed in tumor specimens as compared with normal mucosa. PGE(2) levels were significantly higher in metastatic tumors than in nonmetastatic ones (P = 0.03). CONCLUSIONS: COX-2 is related to tumor angiogenesis in colorectal cancer. It is likely that VEGF is one of the most important mediators of the COX-2 angiogenic pathway.
BACKGROUND & AIMS: Recent studies have shown that cyclooxygenase (COX)-2 and its products, prostaglandins (PGs), may be involved in colorectal carcinogenesis. The aim of this study was to determine whether COX-2 expression and PGE(2) production correlate with microvessel density, vascular endothelial growth factor (VEGF) expression, and tumor metastasis in humancolorectal cancer. METHODS:Tumor samples and adjacent normal mucosa were obtained from 31 surgical specimens. Immunohistochemical expression of COX-2, VEGF, and CD31 was analyzed on paraffin-embedded tissue sections. COX-2 and COX-1 proteins were determined by Western blot analysis. COX-2 and VEGF messenger RNA expressions were evaluated using Northern blot analysis. PGE(2) production was determined by specific radioimmunoassay. RESULTS: The immunohistochemical expressions of both COX-2 and VEGF were significantly correlated with microvessel density (P = 0.02 and P = 0.002, respectively). A significant correlation was found between COX-2 and VEGF expression (P = 0.004). Western analysis confirmed the up-regulation of COX-2 protein expression. COX-2 and VEGF genes were overexpressed in tumor specimens as compared with normal mucosa. PGE(2) levels were significantly higher in metastatic tumors than in nonmetastatic ones (P = 0.03). CONCLUSIONS:COX-2 is related to tumor angiogenesis in colorectal cancer. It is likely that VEGF is one of the most important mediators of the COX-2 angiogenic pathway.
Authors: Marian Grade; B Michael Ghadimi; Sudhir Varma; Richard Simon; Danny Wangsa; Linda Barenboim-Stapleton; Torsten Liersch; Heinz Becker; Thomas Ried; Michael J Difilippantonio Journal: Cancer Res Date: 2006-01-01 Impact factor: 12.701
Authors: Francesco Pepe; Pasquale Pisapia; Maria Laura Del Basso de Caro; Floriana Conticelli; Umberto Malapelle; Giancarlo Troncone; Juan Carlos Martinez Journal: Histol Histopathol Date: 2019-12-24 Impact factor: 2.303