Prostate-specific antigen in the serum of women with benign breast disease

Prostatic-specific antigen (PSA) levels in patients with polycystic ovary syndrome (PCOS): a meta-analysis

Purpose

The polycystic ovary syndrome (PCOS) is a reproductive endocrine disorder, clinically characterized by oligo-ovulation/chronic anovulation, menstrual irregularities, hyperandrogenism (such as hirsutism, acne), hyperinsulinemia, and obesity. Prostatic-specific antigen (PSA) has been identified as a potential new marker in PCOS women. Although the precise role of PSA in PCOS patients still remains undetermined, PSA might serve as a useful clinical marker and might even represent a new diagnostic criterion of hyperandrogenemia in females of PCOS.

Methods

A meta-analysis was performed in the study to identify the association between the polycystic ovary syndrome and prostatic-specific antigen. To identify eligible original articles, we searched a range of computerized databases, including Medline via PubMed, EMBASE, CNKI and Web of Science with a systematic searching strategy. The characteristics of each study and standard mean differences (SMD) with corresponding confidence intervals (CIs) were calculated and subgroup analysis was performed to analyze heterogeneity.

Results

A total of 532 patients from seven articles were included in the meta-analysis. We identified a significant relationship between polycystic ovary syndrome and prostatic-specific antigen, with a pooled SMD of 0.81 (95% CI: 0.58 to 1.04; P < 0.01). The pooled data were calculated with the random-effects model as a moderate significant heterogeneity was found among the studies.

Conclusions

The meta-analysis suggested that there was a significant association between the polycystic ovary syndrome and prostatic-specific antigen and we should not ignore the role of PSA in the PCOS patients in clinical.

Free/Total Serum Prostate-Specific Antigen Ratio in Women with Colorectal Cancer Has Prognostic Significance

PURPOSE

The presence of prostate-specific antigen (PSA) in colon cancer tissues has been shown, but its clinical significance has not been known yet in colorectal cancer patients. We investigated the prognostic significance of percent free PSA value (free PSA/total PSA × 100) in female patients with colorectal cancer.

METHODS

The serum concentrations of total and free PSA were measured by solid-phase two-site immunoradiometric assay in 184 patients.

RESULTS

The cancer-specific survival (CSS) of patients with percent free PSA value ≥35 was significantly better compared to that of patients with percent free PSA value <35 (CSS rate was 82.9 and 55.5 %, respectively; log-rank x² = 8135, p = 0.004). In multivariate Cox analysis, this percent free PSA threshold value had independent prognostic significance (relative risk 0.27, 95 % confidence interval 0.11-0.64, p = 0.003).

CONCLUSION

Percent free PSA value, calculated by serum total and free PSA levels, has prognostic significance in women with colorectal cancer. The studies with larger patient series, utilizing ultrasensitive PSA assays whose lowest detection limit is lower, are required for a clearer understanding of this issue.

Prostate specific antigen (PSA) in diagnosis of polycystic ovarian syndrome - a new insight

INTRODUCTION

Polycystic ovary syndrome (PCOS) is the commonest endocrine disorder and cause of androgen excess in women. Prostate specific antigen (PSA) could be a new marker of hyperandrogenism in PCOS.

OBJECTIVE

The aim of the study was to assess the concentration PSA (total PSA - TPSA and free PSA - fPSA) in 165 patients with PCOS and 40 healthy female controls, the relationship between PSA (TPSA and fPSA) and hormonal parameters and to determine the performance of PSA in diagnosis of PCOS.

RESULTS

Total PSA was higher in PCOS group versus controls. The fPSA was below the lower detection levels among all patients. The median value of FAI was 4.31 in PCOS patients versus 1.79 in controls, p < 0.001. There was a correlation of TPSA and tT (r= 0.173, p = 0.027) and TPSA and FAI (r = 0.2603, p = 0.001). AUC for FAI was 82.1%, threshold 2.56 nmol/l, for tT AUC 80.5%, threshold 0.54 ng/ml, for TPSA AUC 66.3%, threshold 0.005 ng/ml. The ROC analysis for A AUC 62.7%, threshold 3.95 ng/ml.

CONCLUSION

PCOS women have higher serum concentration of TPSA than controls. TPSA positively correlate with T and FAI, which is the best marker for hyperandrogenic states and has better accuracy for tT and total PSA serum levels in diagnostic of PCOS.

Highly sensitive nanoparticle-based immunoassays with elemental detection: Application to Prostate-Specific Antigen quantification

One of the major challenges in developing novel assay methods for the detection of biomolecules is achieving high sensitivity, because of the ultralow concentrations typically in clinical samples. Here, a Mn-doped ZnS quantum dots-based immunoassay platform is presented for highly sensitive detection of cancer biomarkers. Ultrahigh sensitivity is achieved through gold deposition on the surface of the nanoparticle tags acting as catalytic seeds, thus effectively amplifying the size of the metallic nanoparticles after the immunoassay and before the tag detection. Elemental mass spectrometry measurement of the gold content allowed detection of Prostate-Specific Antigen (PSA) at the low attog mL(-1) level. Moreover, the developed method showed not only an extremely high sensitivity for PSA detection but also a broad dynamic range, higher than 8 orders of magnitude, particularly useful for clinical studies involving quantitative detection of diverse biomarkers at their very different relevant concentration levels. Its applicability to discriminate small differences in PSA concentrations at low levels (few pgmL(-1)) in real serum samples was successfully evaluated.

Enzyme-catalysed deposition of ultrathin silver shells on gold nanorods: a universal and highly efficient signal amplification strategy for translating immunoassay into a litmus-type test

A universal and highly efficient signal amplification strategy for use in protein assays is presented in this communication.

A 1024-sample serum analyzer chip for cancer diagnostics

We present a platform that combines microarrays and microfluidic techniques to measure four protein biomarkers in 1024 serum samples for a total of 4096 assays per device. Detection is based on a surface fluorescence sandwich immunoassay with a limit of detection of ~1 pM for most of the proteins measured: PSA, TNF-α, IL-1β, and IL-6. To validate the utility of our platform, we measured these four biomarkers in 20 clinical human serum samples, 10 from prostate cancer patients and 10 female and male controls. We compared the results of our platform to a conventional ELISA and found a good correlation between them. However, compared to a classical ELISA, our device reduces the total cost of reagents by 4 orders of magnitude while increasing throughput by 2 orders of magnitude. Overall, we demonstrate an integrated approach to perform low-cost and rapid quantification of protein biomarkers from over one thousand serum samples. This new high-throughput technology will have a significant impact on disease diagnosis and management.

Reconnoitring the status of prostate specific antigen and its role in women

Prostate specific antigen is considered to be a tumour marker having maximum utility and specificity for prostate cancer since decades. After the discovery of methods to quantify different molecular fractions of prostate specific antigen (PSA), its usefulness in diagnosing early prostate cancer cases has increased tremendously. The "specificity" of PSA, is now challenged by many studies which proved that PSA, once believed to be secreted exclusively by prostatic epithelium, is also present in females. The exact biological role of extraprostatic PSA is still debatable though many theories substantiated by in vitro evidence has been put forward. With the advent of ultrasensitive analytical techniques, PSA is now quantifiable in female serum in its various molecular forms and this has led to many assumptions of it being useful as a marker in female breast cancers. In a similar scenario to prostate cancer, the ratio of free to total PSA is shown to be useful in detecting early breast cancer cases. It is also shown to be a good prognostic indicator and a predictor of response to therapy and recurrence. Apart from its role in breast cancer, it has been advocated to be a marker of hyper androgenic states in women like hirsutism and polycystic ovarian syndrome. Conflicting reports regarding the role of extra prostatic PSA is accumulating but it has been proven beyond doubt that PSA is no longer specific and confined to prostate gland. Various studies have registered that PSA is an ubiquitous molecule, secreted by hormone responsive organs and its synthesis is stimulated by androgens and progesterone but not oestrogens. In this article, a review of various literatures is done about the presence of extra prostatic PSA, its probable role in those sites as well as its utility as a tumour marker in breast cancer.

Plasmon-Enhanced Fluorescence Biosensors: a Review

Surfaces of metallic films and metallic nanoparticles can strongly confine electromagnetic field through its coupling to propagating or localized surface plasmons. This interaction is associated with large enhancement of the field intensity and local optical density of states which provides means to increase excitation rate, raise quantum yield, and control far field angular distribution of fluorescence light emitted by organic dyes and quantum dots. Such emitters are commonly used as labels in assays for detection of chemical and biological species. Their interaction with surface plasmons allows amplifying fluorescence signal (brightness) that accompanies molecular binding events by several orders of magnitude. In conjunction with interfacial architectures for the specific capture of target analyte on a metallic surface, plasmon-enhanced fluorescence (PEF) that is also referred to as metal-enhanced fluorescence (MEF) represents an attractive method for shortening detection times and increasing sensitivity of various fluorescence-based analytical technologies. This review provides an introduction to fundamentals of PEF, illustrates current developments in design of metallic nanostructures for efficient fluorescence signal amplification that utilizes propagating and localized surface plasmons, and summarizes current implementations to biosensors for detection of trace amounts of biomarkers, toxins, and pathogens that are relevant to medical diagnostics and food control.

IGF binding proteins (IGFBPs) and regulation of breast cancer biology

The IGFBP family comprises six proteins with high affinity for the IGFs. Changes in the balance of the components of the IGF system may contribute to the progression of breast cancer. In tumours the abundance of IGFBPs relates to the estrogen receptor status and their production in the breast is controlled by hormones, principally estrogen and progesterone. Important interactions occur between IGFBPs and key growth regulators such as TGF-beta, PTEN and EGF which are reviewed. The conflicting observations between the effects of IGFBPs on the risk of breast cancer, in particular IGFBP-3, obtained from epidemiology studies in comparison to in vivo observations are highlighted and potential explanations provided. The functional activity of IGFBPs can also be affected by proteolysis, phosphorylation and glycosylation and the implications of these are described. The IGFs are generally present at levels far in excess of that required for maximal receptor stimulation, and the IGFBPs are critical regulators of their cellular actions. IGFBPs can affect cell function in an IGF-dependent or independent manner. The key mechanisms underlying the intrinsic actions of the IGFBPs are still in debate. IGF bioactivity locally in the breast is influenced not only by local tissue expression and regulation of IGFs, IGFBPs and IGFBP proteases, but also by these factors delivered from the circulation. Finally, the therapeutic potential of IGFBPs-2 and -3 are considered together with key questions that still need to be addressed.