Comparative genomic hybridization reveals extensive variation among different MCF-7 cell stocks

Comparative genomic hybridization (CGH) allows the detection of DNA sequenc e copy number changes on a genome-wide scale in ct single hybridization rea ction. The ability of CGH to be applied to formalin;fixed, paraffin-embedde d tumor samples has lead to its widespread application in the cytogenetic a nalysis of archival material. When setting up CGH in the laboratory, rigoro us control experiments must be carried out to ensure that the losses and ga ins are scored correctly. Groups interested in breast cancer frequently use the MCF-7 cell line as a positive control in these experiments, comparing the results to previously described genetic alterations. Here we present th e results of CGH carried out with three stocks of MCF-7 cells. The cells di ffer widely in their proliferative response to 17-beta estradiol and show e xtensive variation in copy number changes affecting specific chromosomal re gions. We suggest that care must be taken, therefore, when choosing a cell line as a positive control for CGH experiments. (C) Elsevier Science Inc., 2000. All rights reserved.