Nuclear localisation of glutathione S-transferase π is an evaluation factor for drug resistance in gynaecological cancers

Aims: Nuclear glutathione S-transferase pi (GST pi) has been reported to protect cancer cells against anticancer drugs. The aim of the present study was to evaluate the clinical significance of nuclear GST pi in gynaecological cancer. Materials and methods: We carried out an immunohistochemical analysis of GST pi, and examined the correlation between nuclear GST pi expression and prognosis in 43 epithelial ovarian cancers. We compared expression levels before and after chemotherapy in uterine cervical cancers and endometrial cancers. Results: The 5-year progression-free survival rate of the nuclear GST pi-positive group was lower than that of the cytoplasmic GST pi-positive group, and was significantly lower than that of the negative group (14.3% vs 34.8% vs 66.7%; P = 0.041). The expression of nuclear GST pi was compared before and after chemotherapy in uterine cervical and endometrial cancers. In eight out of 12 cases (66.7%), the expression turned positive after the chemotherapy. Conclusions: We suggest that nuclear localisation of GST pi is associated with drug resistance. The nuclear localisation of GST pi in tumour cells is a useful prognosticator, and may contribute to the selection of anticancer drugs for gynaccological cancers. (c) 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.