At present, no commercially available biomarkers have been identified to differentiate between men with and without prostate cancer (CaP), or to differentiate high risk CaP from indolent CaP better than the PSA test. The widespread use of PSA testing has resulted in 1.3 million additional men diagnosed and 1 million men treated for CaP unnecessarily. In addition, the PSA test has been reported to be of limited value in differentiating benign prostatic disease from CaP and this has resulted in 700,000 unnecessary prostate biopsies annually in the U.S.
Progression of CaP is accompanied by modulation of several key regulatory molecules, including vascular endothelial growth factor, interleukin-8 (IL-8), basic fibroblast growth factor (FGF), tumor necrosis factor-α, and IGF-1 and their receptors. These changes may take the form of up or down-regulation of growth factors or their receptors as well as changes in paracrine or autocrine mediation of growth. Scientists at Roswell Park Comprehensive Cancer Center have done a pilot study involving concurrent serum measurements of IL-8, TNF-α, and sTNFR1 in normal healthy individuals (controls), men with elevated PSA with a negative prostate biopsy (e1PSA_negBx), patients diagnosed with localized CaP, and patients with castrate resistant prostate cancer (CRPC).