Ploidy and Gender in Cancer Survival.
Iver Petersen, Susanne Schulze. Jena University Hospital, Jena, Germany
Background: Ploidy is related to the chromosome complement or the DNA content of cells with aneuploidy being defined as numerical chromosome aberrations or DNA content deviations from the normal state. Ploidy and gender were both related to cancer survival. We aimed to characterize these phenomena in a wide spectrum of neoplasms and to look for potential correlations. In addition we were interested in the ploidy level of different tumor types, in particular the state of near-triploidy.
Design: To characterize the influence of gender a literature search was performed for 27 tumor types. All entities were categorized by the strength of evidence based on the number of studies reporting differences in survival between men and women. In addition, the Mitelman database of chromosomal alterations was evaluated for the major tumor types occurring in both women and men. Numerical gonosome alterations were documented and mean chromosome numbers were converted into histograms to provide insight into the ploidy level of 37 cancer types.
Results: In total, 36.859 karyograms from the Mitelman database were analyzed. Numerical gonosome alterations were more frequent in males than females suggesting a potential link with gender differences in survival. Near-triploidy was a common phenomenon in many, but not all tumor types suggesting that it represents a metastable condition of the cancer genome. It was not related to gender differences in survival. However, the extent of triploidy and aneuploidy was associated with poor prognosis in carcinomas. There was no single case in the Mitelman database with normal chromosome number (n=46) that did not carry at least one structural or numerical aberration.
Conclusions: The data highlights the importance of chromosomal changes in tumor formation and progression. Near-triploidy is a common phenomenon and potentially linked to poor prognosis. Published data indicate that tripolar mitoses are related to triploidy and may thus be used as a surrogate marker for this ploidy state. In addition, triploidy/tripolar mitosis may be useful for differential diagnosis since it is virtually absent in some tumor types while frequent in others. Genomic imbalance of the sex chromosomes is potentially related to gender differences in survival.
Wednesday, March 2, 2011 9:30 AM
Poster Session V # 234, Wednesday Morning