Possible Prostate Cancer Marker Found - Who gets Prostate Cancer

Possible Prostate Cancer Marker Found

Elevated concentration of a compound detected in the tumor tissue, blood, and urine of men with prostate cancer could indicate the aggressiveness of the disease, new research suggests. Levels of the compound, a metabolite called sarcosine, were elevated in men who had localized prostate cancers compared with benign adjacent tissue, and were even higher in metastatic disease. In addition, experiments with cultured cells indicated that sarcosine may actually contribute to the aggressiveness of prostate cancer, making the associated biochemical machinery a possible therapeutic target, the researchers reported in the February 12 Nature.

If confirmed, the discovery could lead to potentially noninvasive tests for identifying aggressive prostate tumors, perhaps by combining a panel of metabolites with other biomarkers. Physicians currently cannot predict which of these tumors are life threatening.

Sarcosine was identified during a systematic analysis of more than 1,100 metabolites in 262 clinical samples, including tissue, urine, and plasma from men without prostate cancer and those who had various stages of the disease. Dr. Christopher Beecher of the University of Michigan Medical School and his colleagues identified 87 metabolites that could distinguish prostate cancer from benign prostate tissue. Six of these, including sarcosine, had even higher levels in metastatic disease.

Additional experiments led by Dr. Arul Chinnaiyan, an NCI Early Detection Research Network investigator at the University of Michigan, implicated sarcosine in prostate cancer progression. Adding sarcosine to benign prostate cells caused the cells to become more invasive, while reducing sarcosine levels in cancer cells reduced their invasive capability and made them behave more like normal cells.

At a press briefing, Dr. Beecher stressed the importance of the unbiased nature of the study, noting that sarcosine had not been associated with prostate cancer previously. Dr. Chinnaiyan added that profiling all of the metabolites in cells, collectively called the metabolome, could complement large-scale investigations of genes and proteins. “This should give us a more holistic picture of the molecular alterations that occur in cancer,” he said.