Prognostic value of prostate secretory protein of 94 amino acids and its binding protein after radical prostatectomy.
OBJECTIVE
To establish the prognostic value of total and free prostate secretory protein of 94 amino acids (PSP94) and the PSP94-binding protein (PSPBP) following radical prostatectomy.


METHODS
One hundred and eighty-five serum samples were obtained from patients with localized prostate cancer prior to treatment with radical prostatectomy at Virginia Urology (Richmond, VA). Patients were followed up for a median of 48 months (range, 1-66 months) and biochemical relapse was indicated as total prostate-specific antigen (tPSA) levels increasing to > 0.1 ng/mL. The available clinical variables included initial tPSA, Gleason score, surgical margin status, and clinical stage. Total PSP94, free PSP94, and the PSPBP were quantified in the pretreatment serum using new ELISA tests (Medicorp, Inc. and Ambrilia Biopharma, Inc., Montreal, Quebec, Canada). Univariate and multivariate Cox proportional hazards models were used to assess the ability of PSP94 and PSPBP to predict time to recurrence.


RESULTS
Thirty-one patients had biochemical recurrence. Gleason score, margin status, clinical stage, and initial tPSA significantly predicted recurrence risk (all P < 0.001). In addition, PSPBP was negatively associated with recurrence risk (P = 0.005), and, consistent with previous studies, the bound/free PSP94 ratio was positively associated with recurrence risk (P = 0.008). Multivariate analysis showed that PSPBP, as well as the bound/free PSP94 ratio, were independent predictors of biochemical relapse risk adjusting for tPSA, Gleason score, and margin status.


CONCLUSIONS
Bound/free PSP94 and PSPBP are novel and independent prognostic markers following radical prostatectomy for prostate cancer.
Reeves
Jonathan R
JR
Ambrilia Biopharma Inc., Chemin du Golf, Verdun, Quebec, Canada. jonathan.reeves@sympatico.ca
Dulude
Hélène
H
Panchal
Chandra
C
Daigneault
Luc
L
Ramnani
Dharam M
DM
D014408:Biomarkers, Tumor / Q000097:blood; D002352:Carrier Proteins / Q000097:blood*; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D008297:Male; D009367:Neoplasm Staging; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000601:surgery*; D029584:Prostatic Secretory Proteins / Q000097:blood*; D012008:Recurrence; D015203:Reproducibility of Results; D000509:alpha-Fetoproteins / Q000032:analysis
D014408:Biomarkers, Tumor; D002352:Carrier Proteins; D006023:Glycoproteins; C501293:PI16 protein, human; D029584:Prostatic Secretory Proteins; D000509:alpha-Fetoproteins; C043076:beta-microseminoprotein; D017430:Prostate-Specific Antigen