1. ¹Department of Internal Medicine III, University of Ulm, Ulm, Germany
2. ²Department of Physiological Chemistry, University of Ulm, Ulm, Germany
3. ³Department of Pathology, Stanford University, Stanford, CA, USA

Correspondence: Dr L Bullinger, Department of Internal Medicine III, University of Ulm, Robert-Koch-Str. 8, 89081 Ulm, Germany. E-mail: lars.bullinger@uniklinik-ulm.de

Received 3 February 2006; Revised 13 March 2006; Accepted 15 March 2006.

Abstract

To model and investigate different facets of leukemia pathogenesis, a widely accepted approach is to use immortalized leukemia cell lines. Although these provide powerful tools to our knowledge, few studies have addressed the question whether hematopoietic cell lines represent accurate and reliable model systems. To improve the molecular characterization of these model systems, we analyzed 17 myeloid leukemia cell lines using DNA microarray technology. By array-based comparative genomic hybridization, we identified recurrent genomic DNA gains and losses, as well as high-level amplifications. Parallel analysis of gene expression helped delineate potential candidate genes, and unsupervised analysis of gene expression data revealed cell lines to cluster in part based on underlying cytogenetic abnormalities. Comparison with clinical leukemia specimens showed that key signatures were retained, as myeloid cell lines with characteristic cytogenetic aberrations co-clustered with leukemia samples carrying the respective abnormality. Signatures were also quite robust, as expression data from cell lines correlated highly with published data. Thus, our analyses demonstrate myeloid cell lines to exhibit conserved and stable signatures reflecting the underlying primary cytogenetic aberrations. Our refined molecular characterization of myeloid cell lines supports the utility of cell lines as faithful and powerful model systems and provides additional insights into the molecular mechanisms of leukemogenesis.