A better test for prostate cancer
High concentrations of the compound sarcosine in urine signal an aggressive cancer
By Nathan Seppa
A compound called sarcosine may distinguish slow-growing prostate cancers from those likely to spread and become lethal, a new study shows. And in an unexpected finding, benign prostate cells take on cancerous characteristics in lab dishes when exposed to sarcosine, suggesting that the compound is less of a bystander and more of a perpetrator in the malignancy, researchers report in the Feb. 12 Nature.
“It’s not only a biomarker for aggressive prostate cancer, but it might be involved in the biology of the cancer,” says study coauthor Arul Chinnaiyan, a Howard Hughes Medical Institute investigator and pathologist at the University of Michigan in Ann Arbor.
Tests for elevated sarcosine also outperformed the most widely used clinical test for detecting prostate cancer. Conveniently, sarcosine can be identified in urine, a less invasive test than the blood analysis needed for the standard prostate-specific antigen, or PSA, test routinely given to men to check for signs of cancer.
To arrive at these findings, Chinnaiyan and his team analyzed 1,126 metabolites in samples of prostate tissue, blood and urine obtained from men with various stages of prostate cancer and from a group of men without the cancer. Sarcosine was undetectable in healthy tissue but turned up in large amounts in prostate cancer confined to the gland and in even greater levels in metastatic cancer.