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USU’s Center for Prostate Disease Research Reports New Prognostic Utility of PCA3 Molecular Urine Test
October 6, 2008
BETHESDA, Md. — In a recent report, the collaborative research team from the Center for Prostate Disease Research at the Uniformed Services Universit of the Health Sciences (USU) and Walter Reed Army Medical Center (WRAMC) and Gen-Probe Inc., San Diego, Calif., showed a new promising prognostic utility of the urine PCA3 test.
The study was co-led by Drs. David G. McLeod and Shiv Srivastava from CPDR and Drs. Jack Groskopf and Harry Rittenhouse from Gen-Probe. PCA3 is a prostate specific mRNA that is over-expressed in most prostate cancers and has very high tumor cell specificity. PCA3 does not code for a protein, but can be amplified and quantified from whole urine after digital rectal exam (DRE). While urine based PCA3 assays show promise in predicting biopsy results, limited data are available to address its prognostic value. The research shows that the PCA3 score in the post-DRE urine of prostate cancer patients is a strong independent predictor of extracapsular extension (ECE), and functions synergistically with other clinical information. Remarkably, when PCA3 score was combined with pre-operative PSA and biopsy Gleason score, the area under the ROC curve for prediction of ECE approximated 90 percent. This study confirms and expands on findings from a recent report in the Journal of Urology showing that PCA3 score correlates with tumor volume and pathologic Gleason score. The PCA3 urine test therefore has potential to provide valuable prognostic information, and may help to determine which patients are candidates for active surveillance versus more aggressive treatment. Further studies addressing the value of this assay in various populations are presently underway.
A collaborative partnership between CPDR in the Department of Surgery at USU, Gen-Probe, and representatives of The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. was launched in early 2006 to develop a new diagnostic test for prostate cancer. Gen-Probe has been leading the development and use of urine PCA3 assay to improve prostate cancer diagnosis. The CPDR team has been credited with the discovery of novel prostate cancer specific gene expression alterations such as PCGEM1, PSGR and ERG and evaluation of these genes in diagnosis or prognosis. The CPDR group had earlier defined a prostate cancer gene panel of three genes (ERG, PCA3 and AMACR) with potential in prostate cancer diagnosis.
The CPDR mission is fulfilled primarily through its three principal programs – the Clinical Research Center, the Basic Science Research Program and the National Multicenter Prostate Cancer Database– and through a robust education and training program that operates out of its Headquarters location, the Clinical Research Center, and the original laboratories at USUHS. CPDR is also committed to patient outreach, primarily through its affiliation with the WRAMC US TOO! organization and through a heavy schedule of health fairs in which it participates.
