Can the centrosome be a marker for DNA ploidy in breast cancer?

The role of DNA ploidy in genomic instability of cancer cells and prognosis has been described in a number of studies. The role of the centrosome in cell cycle has also been reported.

In this study, we aimed to investigate the correlation between the centrosome and DNA ploidy in breast cancer in a search for a cytologic predictive and prognostic marker.

Cell prints were prepared from cell culture of mesothelial cells, fibroblast cell line MRC5 and breast cancer cell lines MCF7 and T47D. Indirect immunofluorescence was used with anti-γ-tubulin and centrosomes were quantified using a fluorescence microscope. DNA ploidy was scored with the DNA index analyzed by flow cytometry.

The normal mesothelial cells (94% of the cells with one detected centrosome) and MRC5 diploid cells (68% with two centrosomes) were used as quality controls. A correlation between the number of centrosomes and DNA ploidy was found in MCF7 cell lines (64% of the cells with a number of centrosomes ≥ 3). It was not observed in invasive breast cancer samples; however, the frequency of cells with centrosomes ≥ 3 was found to be slightly higher in DNA aneuploid samples than in DNA diploid samples (15% vs 13.3%).

Quantification of centrosome appears to be correlated to DNA ploidy in breast cancer cell lines and slightly associated to DNA aneuploidy in invasive breast cancer. Studies analyzing a larger number of samples as well as morphological abnormalities of the centrosome are needed.