Expression Of VEGF-C And VEGFR-3 In Esophageal Carcinoma And Their Significance

Matastasis is one of the important biological characteristics of malignant tumors,which often resulted in the aggravation of patients,and the lymphatic metastatic spread of tumor cells is responsible for the majority of cancer deaths,but the mechanism of lymphatic metastasis is not clear up to date.VEGF-C is a member of the VEGF family of growth factors,which are highly conserved secreted glycoproteins that regulate vasculogenesis,hematopoiesis,angiogenesis,lymphangiogenesis,and vascular permeability are implicated in many physiological and pathological processes.VEGF-C binds VEGFR-2 and –3.VEGFR-2 is expressed almost exclusively by vascular endotheliar cells and hematopoietic precursors,whereas VEGFR-3 is widely expressed in the early embryonic vasculature but expressed restrictly in the lymphatic endothelium at later stages of development and in postnatal life.VEGFR-3 is highly expressed in lymphatic endothelial cells of lymph node metastasis, lymphangiosarcoma, hemangioma, KS spindle cells. Because of the combination of VEGFR-3 with VEGF-C, VEGF-C might be closely related to the development of the lymphatic system.The results and conclusions of my study are as follows:First,73 samples of esophagal squamous carcinoma were collected from Southwest hospital and Xinqiao hospital. With RT-PCR,the expression of VEGF-C and VEGF-3 in the tumor tissue and the tissue around tumor was tested. Among 38 cases with positive expression of VEGF-C,25 cases expressed VEGFR-3 positively. However,among those with negative expression of VEGF-C,only 12 cases expressed VEGF-3 positively. Among the eight cases with positive expression of VEGF-C in the tissue around tumor, the rate of lymph node metastasis was 50%,and only 18.5% of the cases with negative expression of VEGF-C in the tissue around tumor were complicated with lymph node metastasis. Among all the cases,13 cases were classified into the I grade differentiation (7 cases with positive expression of VEGFR-3), 36 cases were classified into the II grade differentiation (21 cases with positive expression of VEGFR-3),and 24 cases were classified into the III grade differentiation (9 cases with positive expression of VEGFR-3). Simultaneously, one of the 14 I phase cases, 25 of the 45 II phase cases, and 11 of the 14 III phase cases expressed VEGFR-3 positively. Conclusions: The rate of VEGFR-3 positive expression was much higher in the esophagal carcinoma and the surrounding tissue with positive expression of VEGF-C than that in the esophagal carcinoma and the surrounding tissue with negative expression of VEGF-C. The expression of VEGF-C was higher in the carcinoma and the surrounding tissue complicated with lymph node metastasis than that in the carcinoma and the surrounding tissue without lymph node metastasis. The level of the VEGFR-3 expression was irrelevant to the degree of tumor differentiation, but was relevant to the clinical staging.Second,to investigate the expression of VEGF-C and VEGFR-3 at the level of protein, immunohistochemistry and Western blot were adopted. It was found that VEGF-C was expressed in the cytoplasm of the tumor cells and that VEGFR-3 appeared in the cytoplasm of the lymphatic endothelial cells. The rate of the VEGFR-3 positive expression in the lymphatic endothelial cells of the tumor tissue with positive expression of VEGF-C was 6.84±5.98,however, the rate in the lymphatic endothelial cells of the tumor tissue with negative expression of VEGF-C was 2.15±1.97.The difference was significant. Among the 57 cases with lymph node metastasis, the rate of VEGFR-3 positive expression in the lymphatic endothelial cells was 5.66±5.67, and the rate among the 16 cases without lymph node metastasis was 2.89±1.96. The rate of VEGFR-3 positive expression was 61.5%, 52.8% and 41.7% in the high-differentiation, moderate-differentiation and low-differentiation tumor tissue, respectively. The rate of VEGFR-3 positive expression was 14.3%, 53.3% and 78.6% in the I phase, the II phase and the III phase tumor tissue, respectively. Combined with the res...