The researchers published their discoveries in independent papers in the June 9, 2005, issue of the journal Nature. Their findings show that distinctive patterns of activity of microRNAs (miRNAs) in cancer cells can be used to diagnose cancers, reported HHMI investigator Todd R. Golub, who is at the Dana-Farber Cancer Institute and the Broad Institute of MIT and Harvard.

Golub and co-authors H. Robert Horvitz and Tyler Jacks, both HHMI investigators at MIT, showed that miRNA expression profiles can be used to both classify human cancers and to distinguish normal cells from those that are cancerous. The new study shows that microRNA expression profiles can even distinguish cancerous cells that cannot otherwise be identified on the basis of their outward appearance.

In a second paper published in Nature, Gregory Hannon, Scott Lowe and their colleagues showed that a specific cluster of microRNAs can cause lymphomas in mice. Hannon and Lowe, who were recently appointed as HHMI investigators at Cold Spring Harbor Laboratory, say that given the new findings, they agree with a proposal calling for cancer-causing microRNAs to be dubbed "oncogenic micro RNAs," or "oncomiRs," just as cancer-causing genes are called oncogenes. Senior author Scott Hammond of the University of North Carolina at Chapel Hill and Carlos Cordon-Cardo at the Memorial Sloan-Kettering Cancer Center also contributed to the studies.

A third paper in Nature from Joshua Mendell and colleagues at The Johns Hopkins University School of Medicine reported that some microRNAs cooperate with a gene already known to cause human cancers.

"[T]hese three studies change the landscape of cancer genetics by establishing the
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Contact: Jim Keeley
keeleyj@hhmi.org
301-215-8858
Howard Hughes Medical Institute
8-Jun-2005