Glutathione‐S‐Transferase π Expression in Transitional Cell Carcinoma of the Bladder
THOMAS DJ., BIRCH PJ., VICKERS J., ROBINSON M., CLIFFORD S., HALL A., NEAL DE.
Summary Glutathione‐S‐transferase π (GSTπ) is a multifunctional protein that acts as an enzyme, involved in the detoxification of drugs and carcinogens. It has been implicated both in drug resistance and malignant transformation of epithelium. Using an indirect immunohistochemical technique, we have evaluated cytoplasmic and nuclear staining in normal urothelium, 23 superficial bladder tumours and 26 invasive tumours. All 26 invasive tumours had been treated with platinum‐based chemotherapy. Cytoplasmic staining was seen in normal urothelium and all bladder tumours. Nuclear staining was seen in 1 superficial tumour and in 13 invasive tumours. There was no association between nuclear staining and response to chemotherapy. Nuclear staining was seen in 1 area of dysplasia and in 2 of 3 areas of carcinoma in situ. GSTπ expression is not a predictor of response to chemotherapy. Increased intra‐nuclear expression of GSTπ may be associated with progression of transitional cell carcinoma of the bladder. © 1993 British Journal of Urology