Distribution of alpha glutathione S-transferase in ovarian neoplasms: an immunohistochemical study.
OBJECTIVE
Alpha glutathione S-transferase (alpha-GST) has been shown to be an immunohistochemical marker for delta(4-5) isomerase, an enzyme active in steroidogenesis. The purpose of this study was to document the distribution of alpha-GST in ovarian neoplasms in order to evaluate its usefulness as a diagnostic tool.


RESULTS
A total of 92 tumours (25 sex cord/stromal, 53 epithelial and 14 germ cell) were subjected to immunohistochemistry using a commercially available polyclonal antibody to alpha-GST. The avidin-biotin complex was used as a detection system. Positive staining was found in luteinized stromal cells of all tumour types (58/92). This included the Leydig cells of Sertoli-Leydig cell tumours (7/7) and was particularly prominent in the stromal cells of both benign and malignant mucinous tumours (24/25). Granulosa and Sertoli cells showed weak or no intracytoplasmic staining, which is expected because they do not normally produce androstenedione. They did show some intranuclear staining. Malignant mucinous (12/25) and occasional other epithelial tumours showed focal intracytoplasmic positive staining. Yolk sac tumours showed focal positivity (7/8).


CONCLUSIONS
Intracytoplasmic staining of stromal cells is considered to indicate steroidogenesis and intranuclear staining the intracytoplasmic transport function of alpha-GST. The intracytoplasmic staining of mucinous carcinomas might represent an up-regulation of some detoxification function. The findings suggest that antibody to alpha-GST has some value in the investigation of ovarian pathology and could readily be included in any panel of antibodies used to investigate ovarian neoplasms of uncertain histogenesis.
Tiltman
A J
AJ
Department of Anatomical Pathology, School of Pathology, University of Witwatersrand & South African Institute for Medical Research, South Africa.
Ali
H
H
D005260:Female; D005982:Glutathione Transferase / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism*; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000473:pathology
D007527:Isoenzymes; D005982:Glutathione Transferase; C119995:glutathione S-transferase alpha