Human Serum Low Molecular Mass Prostate-specific Antigen As Biomarker.
ABSTRACT: Background:Prostate-specific antigen (PSA) is a glycoprotein tumor marker known to exist as numerous glycospecies. Investigations on its glycobiochemical properties aimed at their use in the preparation of adjuncts in determining PSA concentration for clinical purposes have accumulated a lot of data on its structural properties. In this study, we reconsidered unexplored ubiquitously present low molecular mass species of PSA regarding to molecular mass, origin and pathophysiological source specificity in order to evaluate them as biomarkers. Methods:Data on low molecular mass PSA-immunoreactive species from sera of subjects with prostate cancer (PCa), benign prostatic hyperplasia (BPH), breast cancer (BCa), and urine of healthy males obtained by on-chip immunoaffinity chromatography combined with mass spectrometry were analyzed. Results:The results obtained indicated PSA species common to BCa, PCa, and BPH at 12-13 kDa, 17-19 kDa and 21-24 kDa. The striking difference in predominant frequencies made the profile characteristic in each examined pathophysiological condition. On the other hand, paired groups of prostatic and extraprostatic PSA contained rare species with small differences among groups concerning individual species. Low molecular mass PSA also included rare species unique for each group of samples. Conclusion:The results obtained revealed that uniformity of low molecular mass PSA-immunoreactive species in sera prevails over diversity related to cancer and non-cancer conditions, but at the same time some of them are molecules with biomarker potential for BPH detection.
Project description:Current screening methods towards prostate cancer (PCa) are not without limitations. Research work has been on-going to assess if there are other better tests suitable for primary or secondary screening of PCa to supplement the serum prostate specific antigen (PSA) test, which fails to work accurately in a grey zone of 4-10ng/ml. In this pilot study, the potential roles of urinary polyamines as prostate cancer biomarkers were evaluated. PCa, benign prostatic hyperplasia (BPH) patients and healthy controls (HC) showing PSA>4.0ng/ml were enrolled in the study. Their urine samples were obtained, and the urinary levels of putrescine (Put), spermidine (Spd) and spermine (Spm) were determined by ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometer (UPLC-MS/MS). Receiver operating characteristics (ROC) curve and Student's t-test were used to evaluate their diagnostic accuracies. Among the three biogenic polyamines, Spm had demonstrated a good diagnostic performance when comparing their levels in PCa patients with BPH patients (1.47 in PCa vs 5.87 in BPH; p<0.0001). Results are in accordance with transrectal ultrasound prostatic biopsy (TRUSPB) results, with an area under curve (AUC) value of 0.83±0.03. Therefore urinary Spm shows potential to serve as a novel PCa diagnostic biomarker, which in turn can help to address the limited sensitivity and specificity problem of serum PSA test.
Project description:Prostate Specific Antigen (PSA) fails to discriminate between benign prostatic hyperplasia (BPH) and Prostate Cancer (PCa), resulting in large numbers of unnecessary biopsies and missed cancer diagnoses. Nanovesicles called exosomes are directly detectable in patient plasma and here we explore the potential use of plasmatic exosomes expressing PSA (Exo-PSA) in distinguishing healthy individuals, BPH, and PCa. Exosomes were obtained from plasma samples of 80 PCa, 80 BPH, and 80 healthy donors (CTR). Nanoparticle Tracking Analysis (NTA), immunocapture-based ELISA (IC-ELISA), and nanoscale flow-cytometry (NSFC), were exploited to detect and characterize plasmatic exosomes. Statistical analysis showed that plasmatic exosomes expressing both CD81 and PSA were significantly higher in PCa as compared to both BPH and CTR, reaching 100% specificity and sensitivity in distinguishing PCa patients from healthy individuals. IC-ELISA, NSFC, and Exo-PSA consensus score (EXOMIX) showed 98% to 100% specificity and sensitivity for BPH-PCa discrimination. This study outperforms the conventional PSA test with a minimally invasive widely exploitable approach.
Project description:BACKGROUND:Proteomics may help us better understand the changes of multiple proteins involved in oncogenesis and progression of prostate cancer(PCa) and identify more diagnostic and prognostic biomarkers. The aim of this study was to screen biomarkers of PCa by the proteomics analysis using isobaric tags for relative and absolute quantification(iTRAQ). METHODS:The patients undergoing prostate biopsies were classified into 3 groups according to pathological results: benign prostate hyperplasia (BPH, n = 20), PCa(n = 20) and BPH with local prostatic intraepithelial neoplasm(PIN, n = 10). Then, all the specimens from these patients were analyzed by iTRAQ and two-dimensional liquid chromatography-tandem mass spectrometry (2DLC-MS/MS). The Gene Ontology(GO) function and the transcription regulation networks of the differentially expressed were analyzed by MetaCore software. Western blotting and Immunohistochemical staining were used to analyze the interesting proteins. RESULT:A total of 760 proteins were identified from 13787 distinct peptides, including two common proteins that enjoy clinical application: prostate specific antigen (PSA) and prostatic acid phosphatase(PAP). Proteins that expressed differentially between PCa and BPH group were further analyzed. Compared with BPH, 20 proteins were significantly differentially up-regulated (>1.5-fold) while 26 were significantly down-regulated in PCa(<0.66-fold). In term of GO database, the differentially expressed proteins were divided into 3 categories: cellular component(CC), molecular function (MF) and biological process(BP). The top 5 transcription regulation networks of the differentially expressed proteins were initiated through activation of SP1, p53, YY1, androgen receptor(AR) and c-Myc The overexpression of periostin in PCa was verified by western blotting and immunohistochemical staining. CONCLUSION:Our study indicates that the iTRAQ technology is a new strategy for global proteomics analysis of the tissues of PCa. A significant up-regulation of periostin in PCa compared to BPH may provide clues for not only a promising biomarker for the prognosis of PCa but also a potential target for therapeutical intervention.
Project description:Prostate cancer (PCa) is one of the most common malignancies in men worldwide. Serum prostate specific antigen (PSA) level has been extensively used as a biomarker to detect PCa. However, PSA is not cancer-specific and various non-malignant conditions, including benign prostatic hyperplasia (BPH), can cause a rise in PSA blood levels, thus leading to many false positive results.In this study, we evaluated the potential of urinary metabolomic profiling for discriminating PCa from BPH.Urine samples from 64 PCa patients and 51 individuals diagnosed with BPH were analysed using 1H nuclear magnetic resonance (1H-NMR). Comparative analysis of urinary metabolomic profiles was carried out using multivariate and univariate statistical approaches.The urine metabolomic profile of PCa patients is characterised by increased concentrations of branched-chain amino acids (BCAA), glutamate and pseudouridine, and decreased concentrations of glycine, dimethylglycine, fumarate and 4-imidazole-acetate compared with individuals diagnosed with BPH.PCa patients have a specific urinary metabolomic profile. The results of our study underscore the clinical potential of metabolomic profiling to uncover metabolic changes that could be useful to discriminate PCa from BPH in a clinical context.
Project description:Background: Although the prostate-specific antigen (PSA) testing was widely used for early detection of prostate cancer (PCa), it is difficult for PSA to distinguish the PCa from benign prostatic hyperplasia (BPH) patients. Emerging evidence has shown that microRNA (miRNA) was a promising biomarker for PCa screening. Methods: We applied miRNA profiling from microarray or high-throughput sequencing in Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases to identify the differentially expressed miRNAs in PCa patients (n = 1,017) and controls (n = 413). Then, qRT-PCR analysis was used to validate the expression of candidate miRNAs in our independent cohort, include 66 PCa cases and 63 BPH patients diagnosed by biopsy. The area under the receiver operating characteristic curve (AUC) was conducted to evaluate the diagnostic efficacy of miRNAs and PSA. Results: In the microarray analysis, we identified two consistently differently expressed miRNAs (miR-103a-3p and let-7f-5p) between PCa patients and controls. In the subsequent qRT-PCR analysis, the let-7f-5p was upregulated in PCa compared with BPH patients (P=2.17E-07), but no statistically difference of miR-103a-3p expression was observed (P=0.456). The AUC was 0.904 for combination of lef-7f-5p and PSA, which was significantly higher than that of let-7f-5p (0.782) or PSA (0.795) alone (P=7.55E-04 and P=2.09E-03, respectively). Besides, the results of decision curve analysis and nomogram prediction indicated that combination of let-7f-5p and PSA had superior predictive accuracy of PCa. Conclusions: Our study suggests that plasma let-7f-5p combining PSA could serve as potentially diagnostic biomarkers for PCa.
Project description:Metalloproteinases (MMPs) are involved in metastatic tumor processes, with changes in circulating levels detected in several cancer types. Here, we compare serum concentrations of metalloproteinase-1 (MMP-1) across individuals clinically diagnosed with prostate cancer (PCa) or benign prostatic hyperplasia (BPH), correcting results for the rs495366 single nucleotide polymorphism (SNP) that predisposes to differential MMP-1 levels. 196 men aged ?50 years were followed at a university hospital urology outpatient clinic, with clinical, anthropometric, and rectal examinations performed by one urologist. Blood samples obtained prior to any clinical intervention provided baseline MMP-1 and total/free PSA levels as well as metabolic, hormonal, and inflammatory markers. The SNP was genotyped by real-time PCR. Participants with medical and/or laboratory profile compatible with malignancy composed the PCa group when confirmed by the Gleason scale. As expected, A-allele homozygotes showed reduced levels of MMP-1. Genotype-adjusted analyses revealed the mean MMP-1 level as 2-fold higher in PCa carriers compared to BPH patients. No other differences were found according to the prostatic condition or genotypic distribution, except for the expected raise in total and free PSA levels in PCa. In conclusion, increased serum levels of MMP-1 were observed in this context of prostatic malignancy compared to a benign phenotype, regardless of a genetic influence.
Project description:Prostate cancer (PCa) is a common cancer and remains the second-leading cause of cancer-associated mortality in men, but diagnosis of PCa remains a main clinical challenge. To investigate the involvement of differentially expressing genes in PCa with deregulated pathways to allow earlier diagnosis of the disease, transcriptomic analyses of differential expression genes in fine-needle aspiration (FNA) biopsies helped to discriminate PCa from benign prostatic hyperplasia (BPH). We identified 255 genes that were deregulated in prostate tumors compared with BPH tissues. qRT-PCR was conducted to examine the expression levels of the four genes in FNA biopsies and confirmed that ITGBL1 was significantly up-regulated and HOXA7, KRT15 and TGM4 were down-regulated in the PCa compared to the BPH, with a sensitivity of 87.1% and a specificity of 87.8%; the area under the receiver operating characteristic curve was estimated at 0.94, which was significantly improved compared with PSA alone (AUC = 0.82). Moreover, the increased expression of ITGBL1 correlated with total cholesterol, triglyceride and PSA. Our results demonstrated that transcriptomic analyses in FNA biopsies could facilitate rapid identification of potential targets for therapy and diagnosis of PCa.
Project description:Prostate cancer (PCa) screening currently relies on prostate-specific antigen (PSA) testing and digital rectal examination. However, recent large-scale studies have questioned the long-term efficacy of these tests, and biomarkers that accurately identify PCa are needed.We analysed the levels of circulating microRNAs (miRNAs) in patients with elevated PSA who were diagnosed with either localised PCa (n=36) or benign prostatic hyperplasia (BPH, n=31) upon biopsy. Real-time RT-PCR with Taqman probes was used to measure plasma levels of miRNAs. To circumvent problems associated with circulating miRNA quantitation, we computed the expression ratios of upregulated and downregulated miRNAs.The miR-106a/miR-130b and miR-106a/miR-223 ratios were significantly different between the biopsy-positive and BPH groups (P<0.0001), and yielded statistical power values that were >0.99. Both miRNA ratios were highly sensitive and more specific than PSA in discriminating localised PCa from BPH. Receiver operating characteristic curve analysis revealed area under curve values of 0.81 (miR-106a/miR-130b) and 0.77 (miR-106a/miR-223).Testing for circulating miR-106a/miR-130b and miR-106a/miR-223 ratios may reduce the costs and morbidity of unnecessary biopsies and is feasible for large-scale screening, as it requires measuring only three miRNAs.
Project description:Background: Early detection of prostate cancer (PCa) is limited by the lack of accurate non-invasive biomarkers easily evaluable in men within a screening context. Prostate-specific antigene (PSA) measurement leads to high percentages of both false positives and false negatives. In the era of liquid biopsies, we propose to combine PSA dosage with the evaluation of circulating microRNAs (miRs), to discriminate between men harbouring or not PCa. Methods: miR profiling of plasma samples from 60 men with PCa, 51 with benign prostatic hyperplasia (BPH) and 27 healthy donors (HD) was performed using microarrays. Univariate analysis (linear models with an empirical Bayes approach) and multivariate penalized logistic regression models were applied to highlight miRs and clinical variables associated with the presence of malignant disease, and were combined in a classification score. Finally, the developed score was tested on an independent dataset of 242 plasma samples (68 PCa, 8 premalignant lesions, 93 BPH, 73 HD), where miR expression was evaluated by RT-qPCR. Results: Out of 2006 miRs analyzed, a linear combination of miR-103a-3p and let-7a-5p with PSA defined our score. A classification rule based on this score allowed reclassification of samples with accuracy (0.61), sensitivity (0.87), specificity (0.35) and AUC (0.68) higher than those obtained by PSA alone. On the validation set, the same classification rule still performed better than PSA alone in terms of specificity (0.57 versus 0.55) and AUC (0.76 versus 0.74), allowing correct reclassification of all but one tumors not detected by PSA and 33% of BPH with PSA in the 4-16 ng/ml range. Conclusion: The combination of two circulating miRs with PSA could be an interesting biomarker to detect the presence of PCa (even when PSA levels are below the standard cut-off of 4 ng/ml) and the absence of PCa in an important fraction of men with high PSA, who may avoid unnecessary biopsies. Overall design: miR profiling of plasma samples from 60 men with PCa, 51 with benign prostatic hyperplasia (BPH) and 27 healthy donors (HD) was performed using microarrays. Univariate analysis (linear models with an empirical Bayes approach) and multivariate penalized logistic regression models were applied to highlight miRs and clinical variables associated with the presence of malignant disease, and were combined in a classification score. Finally, the developed score was tested on an independent dataset of 242 plasma samples (68 PCa, 8 premalignant lesions, 93 BPH, 73 HD), where miR expression was evaluated by RT-qPCR.
Project description:Autoantibodies against intracellular tumor-associated antigens (TAAs) are commonly found in human cancers. In this study, we characterized the serum autoantibody response to the RalA, Ras-like GTPase, in patients with prostate cancer (PCa). The autoantibodies were detected by immunofluorescence assay in PCa cell lines, ELISA, and immunoblotting in 339 serum samples from patients with PCa and benign prostatic hyperplasia (BPH), and in normal human sera (NHS). The expression of RalA in prostate tumor tissues was evaluated by immunohistochemistry (IHC) in tumor microarrays. The autoantibody level to RalA (median) in NHS was significantly lower than in PCa (0.053 vs 0.138; P < 0.001) and BPH (0.053 vs 0.132; P < 0.005) groups. The circulating anti-RalA autoantibody could distinguish PCa patients from normal individuals with the area under the receiver operating characteristic (ROC) curve (AUC) performing at 0.861, with sensitivity of 52.9% and specificity of 91.0%. Elevation in serum immunoreactivity was observed in PCa patients after radical prostatectomy. The combined use of both anti-RalA autoantibody and PSA showed a significantly higher discriminatory ability compared with either of those markers alone. RalA protein expression was detected by IHC in 85.3% of tumor tissues from PCa patients, but without significant difference compared to BPH or normal control tissues. Together, our study shows the additional benefits of anti-RalA autoantibody as a potential serological biomarker for PCa, particularly in patients with normal PSA, and further demonstrate the utility of biomarker combinations in the immunodiagnosis of PCa.