DENVER—Engrailed-2 (EN2) protein is a transcription factor secreted from tumors and present in the urine of men with prostate cancer. As a result, it shows promise as a possible biomarker for the malignancy.
Richard Morgan, PhD, Senior Lecturer in Molecular Oncology at the University of Surrey in Guildford, United Kingdom, and colleagues collected urine from 400 men with prostate cancer or noncancerous abnormalities after saturation biopsy.
The investigators detected EN2 in the untreated, unconcentrated urine of 40% of the men with prostate cancer but not in any of the men with benign prostatic hyperplasia, prostatitis, or no prostatic abnormalities. Dr. Morgan’s team reported its findings here at the 2009 annual meeting of the American Association for Cancer Research.
Although the test requires investigation in more patients, there’s a possibility that it could be used in U.S. clinics by 2011 if trials go well, Dr. Morgan told Renal & Urology News. The test could provide a better way to determine which men with elevated PSA levels have prostate cancer instead of other prostatic abnormalities.
EN2 is a homeodomain-containing transcription factor with a high degree of functional conservation during early development, according to the researchers. EN2 is unusual for a transcription factor in that it can be secreted from some cells and internalized by others.
In addition, it appears to have a second, independent function in translational regulation. EN2 also may be a potential oncogene in breast cancer.
“If [a man has] Engrailed 2 in [his] urine, then it would suggest that [he has] prostate cancer. So it could mean that treatment could begin and it would avoid the need for biopsy,” Dr. Morgan said. “The test is fairly straightforward so I would think the cost would be similar to [that of] PSA, which is a fairly cheap test.”