In a paper being published in the Oct. 28 issue of Science, the research team indicates that these chromosomal rearrangements induce specific genes to merge, creating what scientists call a gene fusion. U-M researchers detected the unique molecular signature of these fused genes in the majority of prostate cancer tissue samples they analyzed, but found no evidence of gene fusion in benign prostate tissue or in prostate tissue with non-cancerous changes.
"The data in our study provides tantalizing evidence that gene fusion is the causative agent - the initiating event - in prostate cancer," says Arul M. Chinnaiyan, M.D., Ph.D., the S.P. Hicks Collegiate Professor of Pathology in the U-M Medical School, who directed the study. "It's what drives the aberrant over-expression of cancer-causing genes and is the first step in the progression of tissue changes leading to prostate cancer."
Because this particular gene fusion occurs only in prostate cancer, a diagnostic test to detect, in blood or urine, the fused genes or their protein products would be specific for prostate cancer and far more accurate than current screening tests, according to Chinnaiyan. And if scientists could find a way to block the gene, it could be the basis for a new, effective treatment for prostate cancer.
According to the American Cancer Society, more American men will be diagnosed with prostate cancer this year than with any other type of cancer. The American Cancer Society estimates that, in 2005, 232,000 men in the United States will be diagnosed with prostate cancer and 30,350 men will die from the disease. It is the second most common cause of cancer-related deaths in men.