ヒト肺癌におけるGlutathione S-transferase π formの発現に関する免疫組織化学的研究

Abstract

Expression of glutathione S-transferase π form (GST-π) and μ form (GST-μ) in human lung squamous metaplasia, carcinomas, and non-cancerous fetal and adult tissues was immunohistochemically investigated, and the usefulness of GST-π expression as a lung cancer marker was evaluated by cytology. The following results were obtained. 1. In fetal lungs, both bronchial and alveolar epithelial cells were positively stained with GST-π. In adult lungs, bronchial epithelial cells were positively stained with GST-π, but alveolar epithelial cells were negatively stained. The staining attitude of GST-μ in fetal and adult lungs was varied. 2. Squamous metaplasias were stained 100% with GST-π but not with GST-μ. 3. Squamous carcinomas were stained 100% with GST-π without relation to cancer cell differentiation. In adenocarcinoma, poorly differentiated cancer cells were negatively stained and the majority of moderately and well differentiated cancer cells were positively stained. The staining attitudes of GST-μ in squamous cell carcinomas and adenocarcinomas were varied. 4. Small cell carcinomas were negatively stained 100% with GST-π and the staining attitude of GST-μ in those carcinomas was varied. 5. The expression of GST-π in cytology as well as histology revealed that this enzyme is a useful marker for the differential diagnosis of small and non-small cell carcinomas of human lung carcinomas.