Single Gene Links Cancers

Canadian researchers have discovered that a common gene links a number of rare reproductive cancers, a finding that could lead to new approaches for treatment.

Ovarian, uterine, and testicular cancer were all found to have the same mutation in a gene called DICER, according to the research published Wednesday in the New England Journal of Medicine.

Scientists have known about DICER for many years, but its exact role in sparking tumor cells to grow has been unclear.

When the gene mutates, DICER's function is changed "so that it participates directly in the initiation of cancer, but not in a typical 'on-off' fashion," said co-author Gregg Morin, a lead scientist from the Michael Smith Genome Sciences Centre at the British Columbia Cancer Agency.

"DICER can be viewed as the conductor for an orchestra of functions critical for the development and behavior of normal cells," he said.

"The mutations we discovered do not totally destroy the function of DICER, rather they warp it — the orchestra is still there but the conductor is drunk."

Researchers are examining whether DICER plays a role in other cancers, and will investigate if mutant DICER can be manipulated to treat the cancers it causes.

Ovarian cancer kills about 15,000 women in the United States each year, and about 22,000 new cases are diagnosed annually.

More than 46,000 cases of uterine cancer and 8,100 deaths from it occur each year in the United States. Testicular cancer is more rare, with 8,300 new cases per year and 350 U.S. deaths, according to the American Cancer Society.

"This breakthrough will be of interest to both the clinical and the fundamental science communities," said Phillip Sharp, Institute Professor at the Massachusetts Institute of Technology and co-winner of the 1993 Nobel Prize in Physiology and Medicine for the discovery of the structure of genes.

"Huntsman, Morin, and colleague's very exciting discovery of specific mutations in DICER, a factor essential for syntheses of small regulatory RNAs in ovarian and other human tumors, could lead to new approaches to treatment."