Inactive free : total prostate specific antigen ratios in ejaculate from men with suspected and known prostate cancer, compared with young control men

Elevated levels of Dickkopf-related protein 3 in seminal plasma of prostate cancer patients

BACKGROUND

Expression of Dkk-3, a secreted putative tumor suppressor, is altered in age-related proliferative disorders of the human prostate. We now investigated the suitability of Dkk-3 as a diagnostic biomarker for prostate cancer (PCa) in seminal plasma (SP).

METHODS

SP samples were obtained from 81 patients prior to TRUS-guided prostate biopsies on the basis of elevated serum prostate-specific antigen (PSA; > 4 ng/mL) levels and/or abnormal digital rectal examination. A sensitive indirect immunoenzymometric assay for Dkk-3 was developed and characterized in detail. SP Dkk-3 and PSA levels were determined and normalized to total SP protein. The diagnostic accuracies of single markers including serum PSA and multivariate models to discriminate patients with positive (N = 40) and negative (N = 41) biopsy findings were investigated.

RESULTS

Biopsy-confirmed PCa showed significantly higher SP Dkk-3 levels (100.9 ± 12.3 vs. 69.2 ± 9.4 fmol/mg; p = 0.026). Diagnostic accuracy (AUC) of SP Dkk-3 levels (0.633) was enhanced in multivariate models by including serum PSA (model A; AUC 0.658) or both, serum and SP PSA levels (model B; AUC 0.710). In a subpopulation with clinical follow-up > 3 years post-biopsy to ensure veracity of negative biopsy status (positive biopsy N = 21; negative biopsy N = 25) AUCs for SP Dkk-3, model A and B increased to 0.667, 0.724 and 0.777, respectively.

CONCLUSIONS

In multivariate models to detect PCa, inclusion of SP Dkk-3 levels, which were significantly elevated in biopsy-confirmed PCa patients, improved the diagnostic performance compared with serum PSA only.

Urinary prostate specific antigen: is the clinical use likely?

Prostate specific antigen (PSA) blood test represents the standard procedure in prostate cancer (CaP) diagnosis and follow-up. However, determination of PSA in the urine, where PSA is present in much higher concentrations than in the blood, still remains in the field of research.

OBJECTIVES

To determine urinary concentrations of PSA (uPSA) in different groups of patients (pts.), and to estimate is it possible to differentiate benign and malignant prostate diseases and to follow-up the results of treatment.

METHODS

Between January 2001. and November 2003., urinary concentrations of PSA were determined at 142 pts. divided in seven groups: 1. young and healthy volunteers, 2. "BPH-24": pts. with benign prostatic hyperplasia (BPH) who collected the sample of 24-hour voided urine, 3. "BPH-I": pts. with BPH who collected the first portion of first urinary voiding, 4. "TRUS-CaP": pts. with CaP which gave the first portion of urine just prior to transrectal ultrasound-guided prostate biopsy (TRUS- biopsy), 5. "TRUS-non-CaP": pts. who gave first portion of urine prior to TRUS-biopsy, but biopsy did not prove the presence of CaP, 6. "RRP": pts. who underwent radical retropubic prostatectomy (RRP), 7. "AAT": pts. who underwent androgen deprivation therapy.

RESULTS

Average uPSA value in the group of young and healthy volunteers, was 13.8 +/- 19.6 ng/ml, in "BPH-24": 38.0 +/- 44.4 ng/ml, in "BPH-I": 140.8 +/- 140.9 ng/ml, in "TRUS-CaP": 234.8 +/- 277.7 ng/ml, in TRUS-non-CaP: 113.1 +/- 148.5 ng/ml, and in the group "RRP": 4.4 +/- 4.7 ng/ml. There was no statistically significant difference of average uPSA values between "BPH-I" and "TRUS-CaP" groups. The significant difference was found between the group of young volunteers and "BPH-I". In "TRUS-CaP" group, there was strong correlation between tumour size and aggressivenes and uPSA concentration. Finally, PSA and uPSA decline during androgen deprivation therapy, strongly correlated (up to r = 0.95).

CONCLUSIONS

Determination of uPSA cannot differentiate BPH and CaP. However, in the group of pts. with proven localized CaP, uPSA can provide additional information concerning T-staging. Moreover, simultaneous monitoring of PSA and uPSA response on hormonal therapy, can provide an early recognition of androgen-indiferent CaP (AIPCA) and hormone-resistent CaP (HRPCA).

Androgen receptor CAG repeat length correlates with semen PSA levels in adolescence

BACKGROUND

Androgens exert their action through the androgen receptor (AR). The length of the AR CAG repeat is inversely correlated to receptor function and short CAG length might be a risk factor for development of prostate cancer. Our aim was to investigate whether CAG repeat number might have an impact on prostate function in adolescence.

METHODS

AR genotyping was performed by direct sequencing of leukocyte DNA from 274 military conscripts. All men underwent endocrine evaluation and semen analysis.

RESULTS

PSA in seminal plasma, total sperm count and motility all are inversely correlated with CAG numbers (rho = -0.128, P = 0.038; rho = -0.156, P = 0.010; rho = -0.158, P = 0.011), whereas serum levels of free testosterone (rho = 0.132; P = 0.029) and luteinizing hormone (rho = 0.126; P = 0.037) are positively correlated to CAG length. No correlation between seminal PSA and serum testosterone, neither free nor total, was found.

CONCLUSIONS

In adolescence, AR genotype, but not serum testosterone, is associated with the level of seminal PSA.