The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Åke Borg

Åke Borg

Principal investigator

Åke Borg

Genetic aberrations in hypodiploid breast cancer: frequent loss of chromosome 4 and amplification of cyclin D1 oncogene

Author

  • M M Tanner
  • R A Karhu
  • N N Nupponen
  • Åke Borg
  • Bo Baldetorp
  • Tanja Pejovic
  • Mårten Fernö
  • Dick Killander
  • Jorma Isola

Summary, in English

The evolution of somatic genetic aberrations in breast cancer has remained poorly understood. The most common chromosomal abnormality is hyperdiploidy, which is thought to arise via a transient hypodiploid state. However, hypodiploidy persists in 1 to 2% of breast tumors, which are characterized by a poor prognosis. We studied the genetic aberrations in 15 flow cytometrically hypodiploid breast cancers by comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). Surprisingly, numerous copy number gains were detected in addition to the copy number losses. The number of gains per tumor was 4.3 +/- 3.2 and that of losses was 4.5 +/- 3.3 (mean +/- SD), which is similar to that previously observed in hyperdiploid breast cancers. Gains at chromosomes or chromosomal regions at 11q13, 1q, 19, and 16p and losses of 2q, 4, 6q, 9p, 13, and 18 were most commonly observed. Compared with unselected breast carcinomas, hypodiploid tumors showed certain differences. Loss of chromosome 4 (53%) and gain of 11q13 (60%) were significantly more common in hypodiploid tumors. The gain at 11q13 was found by FISH to harbor amplification of the Cyclin D1 oncogene, which is therefore three to four times more common in hypodiploid than in unselected breast cancers (15 to 20%). Structural chromosomal aberrations (such as Cyclin D1 amplification) were present both in diploid and hypodiploid tumor cell populations, as assessed by FISH and CGH after flow cytometric sorting. Together these results indicate that hypodiploid tumors form a distinct genetic entity of invasive breast cancer, although they probably share a common genetic evolution pathway where structural chromosomal aberrations precede gross DNA ploidy changes.

Department/s

  • Breastcancer-genetics

Publishing year

1998

Language

English

Pages

191-199

Publication/Series

American Journal of Pathology

Volume

153

Issue

1

Document type

Journal article

Publisher

American Society for Investigative Pathology

Topic

  • Cell and Molecular Biology

Status

Published

ISBN/ISSN/Other

  • ISSN: 1525-2191