Research On Angiopoietin-2 And VEGF In Colorectal Carcinoma

Angiopoietin-2 (Ang-2) and VEGF are critical regulators of embryonic and postnatal neovascularization.To explore the rule of their expression in colorectal carcinoma and their influence on tumor development,RT-PCR analyses and immunohistochemical assay were performed to examine 60 human colon carcinoma specimens for the expression of Ang-2 and VEGF.lt turned out that:(1) The expression of ANG-2 or VEGF in CRC was significantly higher than those in tissues surrounding original tumor.(2) Though there was significant positive correlation between ANG-2 and the degree of tumor differentiation,no correlation between Ang-2 expression and different clinico-pathological factors including invasion, lymph nodemetastasis,Dukes' stage or histological type was detected.(3) There was no correlation between VEGF expression and different histological type or differentiation. There was correlation between VEGF expression level and different clinico-pathological factors including invasion,lymph node metastasis,liver metastasis and Dukes' stage.(4) The correlation between mRNA expression and protein expression of Ang-2 or VEGF in CRC was statistically significant. But there was no correlation between the expression of VEGF and ANG-2. Author concludes that:(1) The high expression of Ang-2 in poor differentiation subgroups suggests that it may increase the potency of colorectal carcinoma invasion and metastasis.(2) The expression of VEGF turns high in the later period of tumor development.lt is an index for poor prognosis.(3) The high expression of Angiopoietin-2 and VEGF in CRC indicates that both of them play important roles in tumor growth and invasion.(4) To inhibit the function of ANG-2 and VEGF might result in the regression of tumor vasculogenisis on which invasion and metastasis depend.