Expression of the glutathione S-transferase placental form in human lung carcinomas.

Expression of glutathione S-transferase placental form (GST-pi) in human lung carcinoma tissue taken at autopsy or biopsy was investigated immunohistochemically. All of 34 cases of squamous cell carcinomas, including poorly, moderately and well-differentiated examples were shown to stain positively for GST-pi. Poorly differentiated adenocarcinomas were, however, negatively stained (0/5 cases), while moderately and well differentiated adenocarcinomas were found to stain with GST-pi at rates of 69% (9/13 cases) and 71% (5/7 cases), respectively. Six cases of small cell carcinomas examined were all negative. The results indicate that GST-pi may be a useful marker for non-small cell type lung cancer, especially squamous cell carcinoma which is in agreement with findings for rat lung neoplastic lesions reported previously.