A recent study, published in the journal Clinical Cancer Research
, reviewed the surprising results of a new prostate cancer test. Carried out by the University of Surrey, this study identified a protein, Engrailed-2 (EN2), which could detect prostate cancer. EN2 is a protein produced strictly by prostate cancer cells, not normal prostate cells.
The study examined urine samples of 288 men with and without prostate cancer. Researchers found that elevated levels of this protein accurately detected cancer in 66% of men with prostate cancer and could rule out cancer in 90% of men without the disease. Researchers also found EN2 protein in 92% of prostate cancer tissue samples, and found none in the samples of normal prostate tissue. The protein levels in men with prostate cancer were, on average, 10.4 times higher than those without prostate cancer.
The current model used to detect prostate cancer measures levels of prostate specific antigen (PSA) in the blood. Though elevated levels of PSA may indicate prostate cancer, higher levels of PSA can also signify an enlarged prostate. While the PSA test can accurately detect prostate cancer in most cases, the test can also lead to false positives by interpreting raised PSA levels as an indicator of cancer. The other major drawback to the PSA test is the possibility of false negatives, where doctors misconstrue the patient’s elevated PSA levels for an enlarged prostate and conduct no further testing, ultimately failing to diagnose the cancer.
In assessing the diagnostic potential of the EN2 protein, the study found urinary EN2 to be a highly specific biomarker for prostate cancer. Although further research is needed, this study shows promising results of EN2 as a reliable, new diagnostic tool for prostate cancer.
Morgan R, Boxall A, Bhatt, et al. Engrailed-2 (EN2): a tumor specific urinary biomarker for the early diagnosis of prostate cancer. Clin Cancer Res. 2011;17(5):1090-1098.