Prostate cancer - genetic and other markers
In 2006, it is estimated that 234,460 men will be diagnosed with prostate cancer, and 27,350 will die from their disease. Prostate cancer is the most common malignancy in men and is the third leading cause of cancer-related death in men (behind lung cancer and colon cancer). In an effort to lower these numbers, researchers are investigating many possible markers for prostate cancer. These markers may one day help identify men at higher risk.
An example of one such marker is a gene called AMACR (x-methylacyl-CoA racemase). AMACR appears to trigger production of a specific protein found only in cancer cells. This gene has been identified as a potential prostate cancer marker by several groups of researchers. The findings suggest that AMACR could eventually help pinpoint early prostate cancer, and make its diagnosis more accurate. In theory, a blood test for the gene could reduce the need for needle biopsies of the prostate.
The protein produced by AMACR helps the body metabolize certain fatty acids, such as those found in dairy products and beef. Researchers caution that the link, if any, between AMACR and a man's diet requires further study.
Another area of active research is called proteomics. Proteomics identifies small amounts of proteins, peptides, and other small molecules in a patient's blood serum using a technique called mass spectrometry. Recent evidence shows that patterns of these molecules are highly specific. They are also sensitive for a variety of cancers including prostate and ovarian. One possible advantage of proteomics would be to identify patients with cancer without needing to do a biopsy, or better determine who should undergo a biopsy.
Interest in proteomics has risen partly due to the completion of the human genome project. Humans may have as few as 30,000 genes, far fewer than had been predicted. With this finding has come the realization that cancer largely involves protein abnormalities. Some of these abnormalities are abnormal structure, location in the cell, synthesis, and interactions with other proteins and molecules.
While proteomics is still in the investigational stage and not routinely used for diagnosis or treatment at this time, it is expected that advances in this field over the next several years might have relevant and important clinical uses.
In the meantime, the medical community is deeply divided over the issue of screening for prostate cancer. At this time, there is no evidence that detecting prostate cancer early saves lives, and it is possible that the harm caused by subsequent procedures such as surgery, radiation, hormonal therapy or chemotherapy may outweigh any possible benefit.
Reviewed By: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology, University of Chicago Medical Center, Chicago, IL. Review provided byVeriMed Healthcare Network.
Copyright 2013 A.D.A.M., Inc.