Bcl-2 Expression And Significance Of Vegf In Breast Cancer And Its Prognostic Relevance Of The Discussion

Tumor progression is regulated by the balance of proliferation and apoptosis in the tumor cell population. Bcl-2 plays an important role in apoptosis regulation of malignant tumors and its expression is associated with the prognosis of breast cancer. VEGF (vascular endothial growth factor) is a glycoprotein that has the capability of increasing vascular proliferation and permeability. VEGF plays an important role in the progression of invasiveness and metastases in malignat tumors and it has also been found to influence the biological behavior of breast cancer. The progression from normal tissue to invasive cancer is however little understood ,We compared some tumour markers trying to find steps in this progression.OBJECTIVES: To investigate the relationship between the expression of bcl-2, VEGF and other prognostic factors which significantly influence the disease free survival rate after surgical resection of primary breast cancer,(eg: tumor size, lymph node, TNM grades, estrogen and progesterone receptors et al.) Meanwhile, the expression of bcl-2,VEGF,ER,PR,and C-erbB-2 of atypical hyperplasia and normal breast tissues have also been studied.METHODS: Sixty-four woman with primary breast carcinoma were studiedfor the expression of bcl-2 and VEGF proteins. The exprission of ER,PR, C-erbB-2,bcl-2,and VEGF in ninteen benign breast tissiue and twelve atypical hyperplasia breast tissues were also examined by automated immunohistochemical assay.RESULTS: Forty- two(65.63%) and forty(62.5%) breast cancer cases were found positive for bcl-2 and VEGF ,respectively,as indicated by immuno-histochemistry. A statistically significant association was found between expression of bcl-2 and high grade(gradein)(P=0.009), positive lymph nodes (P=0. 014), positivity of ER(P=0.010), positive of PR(P=0.010). The expression of VEGF were not related to menopqusal status but were negatively related to the estrogen receptor and progesterone receptor(P<0.05), at same time, VEGF were positivly related to tumor size(P=0.012),lymph nodes((p=0.004),high grade(P=0. 005),TNM III(P=0.012),C-erbB-2(P=0.001) .In patients who died in five years showed high level of VEGF than the other group's.(p=0.033). Between bcl-2 and VEGF, they were positivly related.(r=0.4172,P=0.0001). And there was a trend that from benignl breast tissues to atypical hyperplasia breast tissues to breast , the expression of bcl-2 and VEGF became more higher. This trend was statistically significant.(p=0.001 ;0.002).CONCLUSION: 1. Bcl-2 plays a role as an inhibitor of apoptosis that may extend the viability of cells containing genetic alterations and facilitate tumor progression; 2.As a potent angiogenic factor, VEGF was associated with a poor prognosis in primary breast cancer. 3. Bcl-2 regulated the progession of cell apoptosis from benign breast tissues to atypical hyperplasia breast tissues to breast cancer and influenced the biological behavior of breast tumor cells. 4. VEGF upregulated bcl-2 expression.The mechanism is still however unknown, and there is a need for more research to test it.