The Study On Relationship Between PIGF And Angiogenesis In Colon Cancer

The colon cancer is a common malignant tumors with a high death rate about 3.54/100,000. which is 5.29 percent of the total death rate of cancer.The main death causes of patients are invasiveness and metastasis of tumors. Angiogenesis is a hot spot of the cancer research because of the significant effect on invasiveness proliferation and malignant of tumor. The previous study showed that VEGF (Vascular endothelial growth factor) plays a key role during the growth of the tumor. While the PIGF(placenta growth factor), as a new member of the VEGFs, was expressed in many tumors. Few researches on PIGF in colon cancer were reported although the functions of the VEGF have been studied many years. In this paper, the study focuses on the expression of the VEGF and PIGF in tissues of colon cancer and para-tumor. The results show that PIGF has an important significance in directing the anti-angiogenesis therapy and raising the survival rates.Materials and methods1.Materials97 samples of the colon cancer come from the general hospital of Shenyang Military Command during 2002 to 2005 with the age from 25 to 69, are 63 male 63 and 34 female . The section are recut for 4μm section and stained with routine HE .2.MethodsImmunohistochemistry: polyclonal anti PIGF was purchased from SantaCruz,monoclonal anti-CD34,VEGF were purchased from Shanghai changdao Company. Streptavidin/Peroxidase(SP) perform according to standard protocol except that the primary antibody were anti-CD34,VEGF,P1GF. Immunohistochemistry was performed according to protocol of ABC Kit.3. Evolution3.1 Evolution of the MVD: The microvessel was labeled by CD34. The stained capillary vessel and microvessel were accounted according to the standard of the Weidner [1]. Any individual brown endothelial cell and cell cluster were account as one while the area of the hemocoele higher than 8 times of diameter of the red cells should be ignored. The methods of count: Count the CD34 positive microvessels under 200×. Four different views were selected random for counting the microvessels. The mean value is the MVD ( number/x200)3.2 Evaluation of VEGF and PIGF : Positive VEGF expression defined as brown particles existed in cytoplasm and membrane.3.3 Statistical analysisStatistical analysis:All statistical analyses were performed using the Statistical Package for SPSS ll.5. The association of variables was evaluated using theχ2 test,t-test and Spearman analysis.ResultsVEGF was expressed in 68.04%(67/96) of the colon cancer. The MVD of VEGF positive colon cancer was 38.2±1.4/oil lens, and 22.1±2.2/ oil lens in VEGF negative tissues. It has significant difference (P<0.01). The MVD of PIGF positive colon carcinoma was 34.1±1.4/ oil lens and 30.8±2.6/ oil lens in PIGF negative tissues. It has significant difference (P<0.01). The MVD of PIGF,VEGF in colon cancer is significantly higher than normal mucous (P<0.05). The MVD of PIGF,VEGF is significant association with colon cancer Duke's stages and the metastasis of lymph. (P<0.05). The immunohistochemistry results showed that the expression level of the VEGF,PIGF in colon cancer have non significant difference with the level of cancer differentiation.The expression of VEGF in colon cancer was significant difference with para-tumor (P<0.05). The MVD in pooly differentiated colon cancer was significant higher than middle differentiated and highly differentiated (P<0 . 05), but there is no significant difference between middle differentiated and highly differentiated colon cancer (P>0 . 05). Theassociation of variables analysis showed that VEGF expression and the MVD value was significantly positive correlation (r=0.541,P<0.01),while PIGF expression and MVD value was also significantly positive correlation(r=0.392,P<0.01).Conclusion:1. The expression of VEGF in three type colon cancer and para-tumor was significant difference. The expression of VEGF in pooly differentiated adenocarcinoma and middly, highly differentiated adenocarcinoma was different.2. The expression of PIGF in three type colon cancer and para-tumor was significant difference. The expression of PIGF in pooy differentiated adenocarcinoma and middle, highly differentiated adenocarcinoma was different.3. VEGF and PIGF play coordinated reaction to angiogenesis in colon cancer, especially in pooly differentiated colon cancer. This provides a new methods using vascular endothelial growth inhibitor to therat colon cancer and raised the survival rate.