Comparison of GST Isoenzyme Expression in Normal and Neoplastic Breast Tissue: Correlation with Clinical and Prognostic Factors

İşcan, Mesude
Sak, Serpil Dizbay
Glutathione S-transferases in breast tissue play an important role in the susceptibility to the mutagenic effects of chemical carcinogens and in the response of breast tumors to chemotherapy. In this study the immunohistochemical staining characteristics of glutathione S-transferase isoenzymes (alpha, mu, pi, and theta) were investigated in invasive duct carcinomas and in normal breast tissue of 43 patients. The relationships between the expression of the GST isoenzymes and some clinicopathological features were also examined. Diffuse cytoplasmic staining of varying intensity was observed for GST alpha, theta, and pi in normal and tumorous breast tissue in 100% of the samples. In normal epithelium there was a stronger intensity of staining for GST alpha, mu. and pi expression than in invasive tumor tissues (P 0.05). In this study significant relationships were observed between microcalcification status and GST mu, between menopause status and GST alpha, and between tumor grade and GST mu expression (P 0.05).


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Citation Formats
S. OĞUZTÜZÜN, M. İşcan, M. ÖZHAVZALI, and S. D. Sak, “Comparison of GST Isoenzyme Expression in Normal and Neoplastic Breast Tissue: Correlation with Clinical and Prognostic Factors,” TURKISH JOURNAL OF BIOLOGY, pp. 89–100, 2009, Accessed: 00, 2020. [Online]. Available: