Researchers at the University of Michigan may have taken us one step closer to a simple urine test that indicates how aggressive a prostate cancer might be, meaning that the prognosis for prostate cancer has just improved.
One of the challenges of this type of cancer is differentiating the aggressive form of the disease from the more relaxed version. Not being able to tell them apart causes treatment (not to mention side effects and stress) that may not even be necessary. Using a powerful new science known as metabolomics, the team found an unknown amino acid derivative, known as sarcosine, that can indicate whether a patient has an aggressive or benign form of the disease.
The groundbreaking work shows the value of metabolomics, a new technology that uses computer-controlled robots, which can quickly identify all the chemicals that accumulate in the body’s cells. This accumulation consists of metabolites, end products of a large number of biochemical reactions that take place in the cells of the body. Sarcosine is one of them.
What the team did was compare the metabolites of normal cells with those of aggressive and non-aggressive prostate cancer cells, finding ten (out of 1,126) metabolites that distinguish normal cells from cancer cells. Even more intriguing, metabolites tend to rise or fall as prostate cancer cells become more aggressive. Cancer-free cells have no signs of sarcosine.
But that is not all …
When benign prostate cancer cells are exposed to sarcosine, they become unsightly, aggressive, and invasive. When aggressive cancer cells are deprived of sarcosine, they become much less aggressive. If the work were confirmed and validated by larger studies, these findings have amazing applications for the diagnosis and treatment of dangerous prostate cancer.
Study leader Arul M. Chinnaiyan, MD, PhD, professor of pathology and urology at the University of Michigan, Ann Arbor, explains: “We have tantalizing evidence that this sarcosine pathway may be involved in the pathogenesis of cancer of the prostate. “The study found that sarcosine levels were elevated in 79% of the aggressive prostate cancer samples, 42% of the early-stage cancer samples, and none of the cancer-free samples.
According to the work, published in a February issue of Nature, sarcosine was better at detecting advanced cancers than the test now used, the traditional PSA test. The study also found that sarcosine may be involved with the same pathways that are introduced in cancer invasiveness, making the substance a potential cancer treatment.
Still, more work is needed. Large numbers of men must be sampled, at all different stages of the disease, before markers can be accurately developed. Estimates from the American Cancer Society have more than 186,000 American men diagnosed with prostate cancer in 2008; the disease will claim more than 28,000 lives. Four out of five cases are diagnosed in men over 65, and only rarely in men under 50. No one knows what causes it, but experts generally agree that what you eat (large amounts of fat from red meat) likely increases your risk.
Another theory suggests that fats activate hormones like testosterone that accelerate the growth of prostate cancer or cause dormant cells to kick in.
Today, there are a variety of different treatments for this disease in older men: new techniques, surgeries, and emerging medications are all available options to help control the prognosis of prostate cancer. Finding the right doctor and treatment is key while you wait for more work to be done.
