Development of an ELISA for sPSP94 and utility of the sPSP94/sPSA ratio as a diagnostic indicator to differentiate between benign prostatic hyperplasia and prostate cancer

Clin Chim Acta. 2014 Sep 25;436:256-62. doi: 10.1016/j.cca.2014.06.006. Epub 2014 Jun 18.


Background: The serum PSA (sPSA) test has low specificity for prostate cancer (PCa), since sPSA also rises in benign prostatic hyperplasia (BPH). Serum PSP94 (sPSP94), a major secreted prostate protein, is indicated as a PCa marker. The potential of sPSP94 and sPSA in conjunction with each other to improve specificity of diagnostic test for PCa needs to be evaluated.

Methods: PCa patients (n=33), BPH patients (n=44) and healthy controls (n=50) were recruited. A serum-based sandwich ELISA was developed to measure sPSP94 concentrations. Utility of sPSP94 in improving specificity of sPSA test was evaluated by studying sPSP94/sPSA ratios of study participants.

Results: Considerable decrease in overlap among sPSP94/sPSA ratio values of BPH and PCa patients was observed, as compared to sPSP94 or sPSA alone. For differentiating between BPH and PCa patients, this ratio had a maximum area under the curve (AUC) of 0.859 (P=0.0132) and had a comparable sensitivity (90.91%) to sPSA with an increased specificity of 70.45%. Further, decision curve analysis (DCA) showed that sPSP94/sPSA ratio had a superior net benefit in identifying PCa, in patients opting for biopsy.

Conclusion: The sPSP94/sPSA ratio can be a better differentiating marker between BPH and PCa, than sPSP94 or sPSA alone.

Keywords: BPH; ELISA; PCa; sPSP94; sPSP94/sPSA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Biomarkers / blood
  • Blood Chemical Analysis
  • Case-Control Studies
  • Cohort Studies
  • Diagnosis, Differential
  • Enzyme-Linked Immunosorbent Assay / methods*
  • Humans
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Prostate-Specific Antigen / blood*
  • Prostatic Hyperplasia / blood*
  • Prostatic Hyperplasia / diagnosis*
  • Prostatic Neoplasms / blood*
  • Prostatic Neoplasms / diagnosis*
  • Prostatic Secretory Proteins / blood*


  • Biomarkers
  • Prostatic Secretory Proteins
  • beta-microseminoprotein
  • Prostate-Specific Antigen