Expression Of Survivin In Colorectal Carcinoma Tissue And Its Relationship With VEGF And MVD

Background and objectives: The building of the blood vessel plays a very important role in the growth and metastasis of the tumor. The blood vessels not only offer oxygen and nourishment for the growth of the tumor, but also offer route for the invasion and metatasis of the tumor. To the contrary, the tumor excretes some kinds of vascular factors for the growth of the blood vessels of tumor. The growth of the blood vessels is a complex process. It is dominated by both the advanced vascular factors and restrained vascular factors. Once lose control, the blood vessels will excess multiplication or excess atrophy.Survivin is a novel member of apoptosis protein family. Its structure and character are very different from other members of inhibitor of apoptosis proteins (IAP). Survivin only has a BIR structure ,not ring structure. It has recently been found in many common human cancers but not in normal tissues. Survivin, a molecule for the the interface between apoptosis and cell cycle, is expressed in the G2/M phase of the cell cycle in a cycle-regulated manner. Survivin binds the terminal effector proteases, caspase-3 and caspase-7 to inhibit cell apoptosis. Formation of three-dimensional vascular tubes in vitro is associated with strong induction of survivin in endothelial cells.The endothelial cell-specific mitogen vascular endothelial growth factor(VEGF) has been found to be expressed by tumor cells through autocrine and paracrine pathwaies. It is the most important advanced vascular factor. VEGF can act on the vascular endothelial and stimulate cell proliferation resulting in the formation ofnewly blood vessels and the tumor growth. There is a close correlation between the process, character, density of microvessel and the ability of tumor growth, invasion and metastasis. The specificity of CD34 antigen is higher than that of other vascular endothelial cell makers.The mechanism of the survivin to promote the growth of the blood vessels is not clear. In order to evaluate the effect of the survivin in occurring, developing of the tumor and formation of the blood vessels, immunohistochemical Streptavidin-Peroxidse (SP) method was used to examine the expression of survivin, VEGF and and the microvessel density(MVD) labeled by anti-CD34 monoclonal antibody, which will offer a approach for the diagnosis and treatment of the tumor.Materials and methods: (1) Tissue specimens used for this study were obtained from 64 colorectal carcinomas and 10 adjacent normal mucosa samples from the resection margins, which were resected surgically or endoscopically from 1999 to 2002 and all confirmed pathologically. All the tissues were fixed in 10% neutral formalin and embedden in paraffin. (2) SP Immunohistochemical staining technique was used to exmine the expression of survivin, VEGF and MVD in normal mucosa and colorectal carcinoma. (3) The data were analyzed by software SPSS 10.0. x2-test or t-test was used to analyze the difference between different groups. P value<0.05 was considered as statistically significant.Results: 1. There was no expression of survivin in para-carcinomatous normal mucosa .The positive expression rate of the survivin in colorectal carcinoma is 50%. There was significant difference between normal mucosa group and colorectal carcinoma group (p<0.01). There was no expression of VEGF in para-carcinomatous normal mucosa .The positive expression rate of the VEGF in colorectal carcinoma is 80%. There was significant difference between normal mucosa group and colorectal carcinoma group (p<0.01).2. According to the degree of differentiation of colorectal carcinoma, 64 cases were divided into high/moderate differentiation group and poor differentiation group. In the two groups, the positive rates of survivin were 45% and 59% respectively, and there was no significant difference between the two groups(p>0.05). The positive rates ofVEGF were 76% and 86% respectively, and there was no significant difference between the two groups(p>0.05).3. According to the Dukes stage, 64 cases were divided...