Anne-Marie Mandard

Expression of p53 in oesophageal squamous epithelium from surgical specimens resected for squamous cell carcinoma of the oesophagus, with special reference to uninvolved mucosa.

Accumulation of p53 protein has been considered an intermediate biomarker in multistage oesophageal carcinogenesis. The aim of the present study was to investigate p53 expression by immunohistochemistry in 13 thoroughly sampled oesophagectomy specimens from a geographical area with a high oesophageal cancer incidence (Basse Normandie, France). Expression of p53 was looked for in tissue samples of cancer, intraepithelial neoplasia, and uninvolved mucosa. The streptavidin biotin peroxidase complex method was used for p53 immunostaining. p53 expression was found in invasive squamous cell carcinoma in 8 out of 11 cases and in intraepithelial neoplasia in 10 out of 11 cases. In all 13 cases, in uninvolved oesophageal mucosa, expression of p53 was focally present in areas of chronic oesophagitis. Chronic oesophagitis has been regarded by epidemiologists as a precursor lesion for squamous cell carcinoma of the oesophagus. Since oesophageal carcinogenesis is a multistage process, the study of precursor lesions could provide information on the timing of p53 gene abnormalities during oesophageal carcinogenesis. These preliminary data require to be confirmed by molecular analysis of the p53 gene.

IMAGE ANALYSIS SOFTWARE FOR AUTOMATIC DNA PLOIDY ASSESSMENT OF ARCHIVAL SOLID TUMOURS

BACKGROUND Image cytometry has proved to provide a good alternative to flow cytometry for DNA ploidy measurement of archival tumors. However, when interactively done this technique is unable to give statistically valuable results within an acceptable time for clinical oncology. METHODS An image cytometer was developed for fully automatic DNA ploidy quantitation, focusing efforts on speed and accuracy. Software functionalities include systematic acquisition of fields on a microscopic slide, detection, localization and sorting of nuclei, computation of the DNA content together with post-processing tools, for a deeper analysis of the DNA ploidy diagram. RESULTS DNA ploidy analysis of archival breast carcinoma samples illustrates the accuracy of DNA ploidy measurements and the sensitivity in the detection of DNA ploidy abnormalities as a result of cell sorting. CONCLUSIONS Fully automatic image cytometry is able to combine qualities of flow cytometry (automatic analysis of a statistically significant collection of cell nuclei) with additional advantages: sorting of unwanted events (debris, stromal and inflammatory cell nuclei) and facilities for an a posteriori control of the quality of cell selection. This method is well suited to DNA ploidy analysis of archival cancer samples.

Pararosaniline Or Acriflavine-Schiff Staining of Epoxy Embedded Tissue After Periodic Acid Oxidation in Ethanol: A Method Suitable for Morphometric and Fluorometric Analysis of Glycogen

A method for preparing tissue sections for automatic image analysis of glycogen is described. Large semithin sections of epoxy embedded tissue fixed in glutaraldehyde-osmium were stained with Schiff reagent and acriflavine (fluorescent staining) after resin removal and periodic acid oxidation in ethanol. We found it essential to avoid tissue rehydration before final staining. The Schiff stain permits an assessment of the cellular volume of glycogen, and the acriflavine allows a fluorometric evaluation of glycogen density.