Detection and mapping of amplified DNA sequences in breast cancer by comparative genomic hybridization.

TLDR

Comparative genomic hybridization was applied to 5 breast cancer cell lines and 33 primary tumors to map genomic regions with increased DNA copy number. Two‑thirds of primary tumors and almost all cell lines exhibited increased copy number in 26 chromosomal subregions, many of which are distinct from known amplified genes and may harbor novel genes driving breast cancer progression.

Abstract

Comparative genomic hybridization was applied to 5 breast cancer cell lines and 33 primary tumors to discover and map regions of the genome with increased DNA-sequence copy-number. Two-thirds of primary tumors and almost all cell lines showed increased DNA-sequence copy-number affecting a total of 26 chromosomal subregions. Most of these loci were distinct from those of currently known amplified genes in breast cancer, with sequences originating from 17q22-q24 and 20q13 showing the highest frequency of amplification. The results indicate that these chromosomal regions may contain previously unknown genes whose increased expression contributes to breast cancer progression. Chromosomal regions with increased copy-number often spanned tens of Mb, suggesting involvement of more than one gene in each region.