Efeitos do raloxifeno sobre a angiogênese do carcinoma de mama de mulheres menopausadas

Abstract

PURPOSE: to evaluate the effect of raloxifene on breast cancer angiogenesis of menopausal women. METHODS: sixteen menopausal women with stage II (>3 cm) estrogen receptor positive operable breast cancer were enrolled in this study. Following confirmation of the diagnosis by incisional biopsy, the patients received 60 mg raloxifene daily for 28 days prior to the definitive surgery. Immunohistochemical study was performed on the sample tumors obtained during the biopsy for the diagnosis and evaluation of the status of estrogen receptor and during the definitive surgery. The anti-CD34 monoclonal antibody was used as a marker for endothelial cells. The vascular unit was considered as any endothelial cell or group of cells of a brownish color, clearly separated from adjacent microvessels, tumor cells or other connective tissue, forming or not lumen. Microvessel count was performed in ten fields of each slide using a 40X objective lens (400X magnification). A microscope coupled to a system of capture and analysis of image was used (Imagelab®). Statistical analysis of data was carried out using the paired Student t-test and significance level was established at p<0.05. RESULTS: mean numbers of anti-CD34 antibody-stained microvessels before and after raloxifene treatment were 44.4±3.5 and 22.6±1.6, respectively. A significant reduction in the number of microvessels following raloxifene therapy was observed (p<0.001). CONCLUSIONS: when administered as primary therapy for menopausal women with breast carcinoma, raloxifene significantly reduced tumoral angiogenesis.