The malignancy index is a robust predictor of prostate cancer.

The objective of this study was to validate the results from our published work and to test the robustness of our unique malignancy index as a (non-invasive) predictor of prostate cancer in fresh blood samples obtained from patients diagnosed with prostate cancer (PCa), benign prostatic hyperplasia (BPH), and healthy volunteers (Controls). The malignancy index was obtained by dividing the product of three biomarker values, [urokinase plasminogen activator (uPA), plasminogen activator inhibitor type-1 (PAI-1), and prostate-specific antigen (PSA)], by the age of the patient/healthy volunteer, using enzyme-linked immunosorbent (ELISA) assay methodology. The results confirmed earlier findings that the malignancy index discriminates prostate cancer from non-prostate cancer. The index significantly separated the PCa group from the Control group with values of 0.0701 (n=54) and 0.0007 (n=47), respectively, by a factor of 100. The malignancy index of the small BPH cohort was found to be 0.0016 (n=20), differing by a factor of 44 from the Control group. When data from the earlier study and the current study data were collectively analyzed, the index again significantly separated the PCa group from the Control group by a factor of 15, with values of 0.0624 (n=125) and 0.0042 (n=110), respectively. However, the same could not be said of the BPH data since the sample size (n=20) was well below par, for comparison. In the initial blood study, the PCa group was significantly separated from the Control group by a factor of 8.5. The data presented here concur with findings in needle biopsies and transurethral resection tissue, reported elsewhere (Bohm et al., 2013; Akudugu et al., 2015). At this preliminary stage, the malignancy index has potential and merit as a prostate cancer biomarker.

The malignancy index in plasma samples as a prostate cancer biomarker.

No unambiguous role of the involvement of uroplasminogen activator (uPA) and plasminogen activator inhibitor type-1 (PAI-1) in prostate cancer has emerged, with current evidence suggesting that neither biomarker is likely of significant clinical value, save as an overall contributor. In this study, we attempt to discriminate prostate cancer from non-cancer in a cohort of plasma samples, using the Imubind ELISA assay. In this cohort, PAI-1 levels are higher in prostate cancer patients than healthy donors; uPA levels are higher in healthy donors than prostate cancer patients; and the uPA/PAI-1 ratio is higher in healthy donors than in prostate cancer patients. To date, and across three prostate sample types, i.e. transurethral resection tissue, needle biopsies, and blood plasma, data have been disparate. Given the inconsistency, a malignancy index was created by dividing the product of three biomarkers [uPA, PAI-1, and prostate specific antigen (PSA)] by the age of the patient/donor. The malignancy index clearly distinguishes prostate disease from non-disease in peripheral blood plasma samples (P=0.0127), concurring with findings in core needle biopsies and transurethral resection tissue, reported elsewhere. This is an important finding given the gravity of prostate cancer and the legions of over-diagnosed and over-treated men worldwide.