Highlights the potential of Rosetta's Flexjet™ array technology for understanding the basis of molecular events recognized as important in cancer -- Such technologies may provide the basis for improved diagnosis, and therefore better treatment of malignant or immortalized cells that define cancer

KIRKLAND, Washington, June 30, 2000 -- Researchers at Rosetta Inpharmatics, Inc. (http://www.rii.com) today, in the July 3rd issue of Nature Genetics, reported findings illustrating the potential for gene expression analysis technologies in deciphering the molecular mechanisms of disease. A team of researchers used a model eukaryotic system to analyze the role of changes in chromosome number (aneuploidy) on gene expression. This study indicated that DNA expression analysis could assist researchers in understanding molecular processes underlying cellular changes known to be important in cancer. Historically, discernible changes in chromosomal size and number have long been recognized as a characteristic of cancer cells. Furthermore, these changes have been linked with the progression of cancer.

"I am very impressed with the power of this technology to pick up differences, in many cases differences as small as two-fold were reproducibly detected. Aneuploidy is fundamental to understanding cancer. Over 90% of cancer cells are aneuploid, making them strikingly different from all normal cells," explained Bert Vogelstein, M.D., Professor of Oncology and Pathology, and Investigator, Howard Hughes Medical Institute, at the Johns Hopkins University School of Medicine. "This represents a novel tool for evaluating and detecting aneuploidy, with potential applicability to human cancer cells."

"These findings provide a clearer way of thinking about aneuploidy in cancer as resulting from selection to compensate for other mutations in the cancer cell," explained Professor Leland Hartwell, Ph.D., President and Director, Fred Hutchinson Cancer Research Center. "That gene mutations may be driving the selection of compensating chromosome aneuploid is a useful paradigm for what is going on in cancer."

Using this technology, Rosetta Inpharmatics' scientists have shown large-scale biases in gene expression, which profoundly affect cellular processes, with the potential to lead to compensatory measures which in some instances confer a selective growth advantage analogous to that observed with cancer cells. These findings were made possible by the combination of Rosetta's FlexJet™ DNA microarray technology and the Rosetta Resolver™ gene expression data analysis system.

Rosetta Inpharmatics offers solutions to the emerging field of informational genomics. By combining the power of informatics and genomics, Rosetta has created a proprietary platform that accelerates and enhances the drug discovery process for pharmaceutical and biotechnology companies, and improves agricultural products. Rosetta Inpharmatics' approach converts the rapidly growing amount of gene expression data, or information about a gene's activity, into organized, statistically driven, information-based results. Rosetta Inpharmatics provides a proprietary gene expression profiling platform, consisting of hardware and software products, that uses gene expression profiles to provide seamless solutions for efficient, cost-effective and powerful discovery programs. Rosetta Inpharmatics' technology builds a critical mass of coherent gene expression data collected from DNA microarrays, which are comprised of DNA fragments attached to glass slides in a grid-like formation. This platform provides comprehensive, simultaneous descriptions of a compound's effect on all relevant targets within a cell.