Expression of anionic glutathione s transferase (GSTπ) gene in carcinomas of the uterine cervix and in normal cervices

Abstract

The aim of the present study was to analyse in invasive carcinomas of the uterine cervix, the anionic glutathione S transferase (GSTπ) gene, possibly implicated in the drug resistance of human cancers. Total RNA preparations obtained from invasive cervical cancers (106 specimens), carcinomas in situ (CIS) (three specimens) and normal cervical epitheliums (24 specimens) were analysed by Northern and slot blot hybridisation. A 0.7 kb GSTtc transcript band was detected in all the cervical specimens. GSTπ mRNA levels were lower in normal cervix (mean: 0.7±0.1 arbitrary units) than in invasive carcinomas (mean: 2.5 ±1.5 units) (Student test P<10-4). However no significant difference was observed between invasive cancers of advanced stages (III and IV) and those of early stages (I and II). The presence of human papillomavirus in cancers and in normal cervices did not influence significantly the GSTtc mRNA level. Neither amplification nor gross rearrangement of GSTπ gene could be observed after Southern blot analysis of genomic DNA. In conclusion, our data indicate that the presence of high levels of GSTπ transcripts in invasive cancers may be a consequence of the multiple biochemical changes which accompany cervical carcinogenesis. © Macmillan Press Ltd., 1991.