[Are centrosomal abnormalities correlated to DNA ploidy in breast cancer?]

ADN ploidy was shown to play a role in genomic instability of cancer cells and prognosis. The implication of the centrosome in the cell cycle was also described. Therefore, new prognostic factors could be suggested for a better-tailored therapy. The purpose of this study is to search for correlation between centrosomal abnormality and ADN ploidy in breast cancer. Cell prints were prepared from cell culture of mesothelial ascitis, fibroblast cell line MRC5 and breast cancer cell lines MCF7 and T47D. Fresh cell prints were also obtained from cases with invasive carcinoma. The centrosome was labelled by an indirect immunofluorescence assay using anti-γ-tubulin antibody and F(ab')(2) FITC before quantification with fluorescence microscopy. ADN ploidy was scored with DNA index obtained by means of flux cytometry. The normal mesothelial cells (94% of cells with only one centrosome) and the diploid cell line MRC5 (68% of cells with two centrosomes) were used as controls. DNA ploidy was found to be correlated with centrosomal abnormality in MCF7 cell line (64% of cells had more than three centrosomes) but not in the 10 cases of invasive ductal carcinoma analysed in this study. The absence of correlation between DNA ploidy and centrosomal abnormality in breast cancer samples may be due to the small numbers of cases, the cell prints or tumorigenesis. Correlation analysis of a larger number of cases and types of breast lesions to numerical and morphological abnormalities of the centrosome are ongoing.