CARCINOGENICITY OF MALATHION AND ESTROGEN IN AN EXPERIMENTAL RAT MAMMARY GLAND MODEL

Breast cancer is considered a major and common health problem in both developing and developed countries. The etiology of breast cancer, the most frequent malignancy diagnosed  in women in the western world, has remained unidentified. Chemicals as the  organophosphorous pesticide malathion have been used to control a wide range of sucking  and chewing pests of field crops, and are involved in the etiology of breast cancers. The  association between breast cancer initiation and prolonged exposure to estrogen suggests  that this hormone may also have an etiologic role in such a process. However, the key  factors behind the initiation of breast cancer remain to be elucidated. The effect of  environmental substances, such as malathion and estrogen was analyzed in an experimental rat mammary gland model. Different cytoplasmic proteins are key in the transformation of a  normal cell to a malignant tumor cell and among these are the Ras super family and Ras  homologous A (Rho-A). Both types of proteins were greater in animals treated with  malathion than those with estrogens. E-Cadherins constitute a large family of cell surface  proteins. Results showed greater expression of E-Cadherin and vimentin than c-Ha-ras and Rho-A in  rats treated by estrogens. In breast cancer, analysis using immunohistochemical markers is  an essential component of routine pathological examinations, and plays an important role in  the management of the disease by providing diagnostic and prognostic strategies. The aim of the present study was to identify markers that can be used as a prognostic tool for breast cancer patients.