Meta-analysis of cancer triploidy : Rearrangements of genome complements in male human tumors are characterized by XXY karyotypes

Abstract

Triploidy in cancer is associated with poor prognosis, but its origins remain unclear. Here, we attempted to differentiate between random chromosomal and whole-genome origins of cancer triploidy. In silico meta-analysis was performed on 15 male malignant and five benign tumor cohorts (2928 karyotypes) extracted from the Mitelman Database, comparing their ploidy and combinations of sex chromosomes. A distinct near-triploid fraction was observed in all malignant tumor types, and was especially high in seminoma. For all tumor types, X-chromosome doubling, predominantly observed as XXY, correlated strongly with the near-triploid state (r ≈ 0.9, p < 0.001), negatively correlated with near-diploidy, and did not correlate with near-tetraploidy. A smaller near-triploid component with a doubled X-chromosome was also present in three of the five benign tumor types, especially notable in colon adenoma. Principal component analysis revealed a non-random correlation structure shaping the X-chromosome disomy distribution across all tumor types. We suggest that doubling of the maternal genome followed by pedogamic fusion with a paternal genome (a possible mimic of the fertilization aberration, 69, XXY digyny) associated with meiotic reprogramming may be responsible for the observed rearrangements of genome complements leading to cancer triploidy. The relatively frequent loss of the Y-chromosome results as a secondary factor from chromosome instability.

Description

Funding Information: Funding: This work has been supported by a grant of the European Regional Development Fund (ERDF) project No. 1.1.1.1/18/A/099 and Alfred Raisner memorial scholarship to N.M.V. Publisher Copyright: © 2019 by the authors.

Keywords

Cancer near-triploidy, Digyny, Karyotype meta-analysis, Male tumors, Whole-genome rearrangements, XXY, 3.1 Basic medicine, 3.2 Clinical medicine, 1.1. Scientific article indexed in Web of Science and/or Scopus database, Genetics, Genetics(clinical), SDG 3 - Good Health and Well-being

Citation

Vainshelbaum, N M, Zayakin, P, Kleina, R, Giuliani, A & Ērenpreisa, J 2019, 'Meta-analysis of cancer triploidy : Rearrangements of genome complements in male human tumors are characterized by XXY karyotypes', Genes, vol. 10, no. 8, 613. https://doi.org/10.3390/genes10080613