Summary Quantitative microspectrophotometric studies have been made on sections of human cervix after staining for reactive protein thiol-groups (PSHr), and the sum of protein thiols with so-called reactive protein disulphides (together abbreviated as TRPS). Measurements were made on normal epithelium, apparently normal epithelium adjacent to a pathological lesion, dysplastic epithelium, carcinoma-in-situ, and adjoining stroma. The numbers of cases studied were: normal healthy controls (53); patients with dysplasias (34) and patients with carcinoma-in-situ (29). In the normal control sections the ratio of PSH, in epithelium:stroma was 2.7 and this ratio was strongly decreased in dysplasias (1.6) and carcinoma-in-situ (1.5); the 3 populations of values had sufficient overlap to prevent this measurement being an effective discriminator. No significant variations were observed with TRPS-values except with changes in the stroma adjacent to apparently normal epithelium. However, the ratio of PSHr:TRPS was effectively discriminatory when this double-staining ratio was calculated for epithelial values:stromal values. These results are discussed in relation to the importance of thiol-groups in cell division and cancer, and the biological implications of similar changes observed in neighbouring apparently normal epithelium.Free thiols and protein-bound thiol groups are very important in many aspects of metabolic control including cell division (Rapkine, 1930;Barron, 1951;Jocelyn, 1972;Friedman, 1973;Kosower & Kosower, 1978;Mannervik & Axelsson, 1980;Ziegler et al., 1980;Scovassi et al., 1983). Moreover, disturbances of the cellular thiol:disulphide balance have been associated with the multifarious changes that occur in cancer compared with the normal situation: [for reviews of the older literature see Harington (1967) (Nohammer, 1982;Schauenstein et al., 1983) that enabled the measurements of reactive protein thiol groups (PSHr), and the sum of all protein-thiol groups with the so-called reactive protein disulphides (together abbreviated as TRPS) in single cells and in tissue sections.In this paper we give results obtained by applying these techniques to some important and common pathological conditions of the human uterine cervix. Our objective was to evaluate the differences that occur in such pathological conditions compared with normal cervix. The background to this microspectrophotometric approach has been reported previously (Nohammer et al., 1984); a summary of results for reactive protein thiols has also been published (Slater et al., 1985); results for reactive protein thiols and reactive protein disulphides in invasive cancer will be published separately (Benedetto et al., 1986).
Materials and methodsCytospectrophotometric measurements were made on fresh-frozen, fixed and stained serial sections prepared from samples of human cervix obtained at operation. The procedures used for the preparation, staining and measurement of reactive protein-thiols (PSH,) and total reactive protein-sulphur (TRPS) have been d...