Identification and Validation of Potential New Biomarkers for Prostate Cancer Diagnosis and Prognosis Using 2D-DIGE and MS

Abstract

This study was designed to identify and validate potential new biomarkers for prostate cancer and to distinguish patients with and without biochemical relapse. Prostate tissue samples analyzed by 2D-DIGE (two-dimensional difference in gel electrophoresis) and mass spectrometry (MS) revealed downregulation of secernin-1 (P < 0.044) in prostate cancer, while vinculin showed significant upregulation (P < 0.001). Secernin-1 overexpression in prostate tissue was validated using Western blot and immunohistochemistry while vinculin expression was validated using immunohistochemistry. These findings indicate that secernin-1 and vinculin are potential new tissue biomarkers for prostate cancer diagnosis and prognosis, respectively. For validation, protein levels in urine were also examined by Western blot analysis. Urinary vinculin levels in prostate cancer patients were significantly higher than in urine from nontumor patients (P = 0.006). Using multiple reaction monitoring-MS (MRM-MS) analysis, prostatic acid phosphatase (PAP) showed significant higher levels in the urine of prostate cancer patients compared to controls (P = 0.012), while galectin-3 showed significant lower levels in the urine of prostate cancer patients with biochemical relapse, compared to those without relapse (P = 0.017). Three proteins were successfully differentiated between patients with and without prostate cancer and patients with and without relapse by using MRM. Thus, this technique shows promise for implementation as a noninvasive clinical diagnostic technique.

Prostate tumor DNA methylation is associated with cigarette smoking and adverse prostate cancer outcomes

“…Differences in the methylation and/or expression of smoking‐associated DMR genes LGALS3 and CLDN5 have also been associated with PCa. In particular, LGALS3 (galectin 3) has known roles in cell adhesion, tumor progression, bone metastasis, and apoptosis .…”

Urinary biomarkers of prostate cancer

“…Only a few urinary markers were reported to be associated with prognosis (Table ). Prostatic acid phosphatase and galectin‐3 were significantly decreased in urine without manipulations from patients with biochemical relapse after prostatectomy ( n = 16) compared with patients without relapse ( n = 52) . PCA3 test at the first follow‐up biopsy was a significant predictor of upgrading to Gleason score ≥7 among 90 men with 5α‐reductase inhibitor during active surveillance.…”

Integrin β4 and vinculin contained in exosomes are potential markers for progression of prostate cancer associated with taxane-resistance

“…The authors performed immunohistochemical analysis of 443 specimens from across all stages of prostate cancer progression and demonstrated that VCL expression was highest in CRPC, but negative or very low in benign prostatic hyperplasia, suggesting that VCL overexpression might contribute to prostate cancer progression by enhancing tumor cell proliferation. Geisler et al (21) recently reported that VCL expression was significantly upregulated in prostate cancer based on the analysis of prostate tissue samples by 2D-DIGE (two-dimensional difference in gel electrophoresis) and mass spectrometry (MS). Intriguingly, the authors showed that urinary VCL levels in prostate cancer patients were significantly higher than in urine from non-tumor patients.…”

“…Although previous studies demonstrated that ITGB4 and VCL play critical roles in various types of cancer including prostate cancer (19)(20)(21)(22)(23)(24)(25)(26), their roles in taxane-resistant prostate cancer have not been clarified. we therefore knocked down ITGB4 and VCL expression by siRNA transfection and examined the effect of silencing on proliferation and taxane-resistance.…”