Bead-based ELISA for validation of ovarian cancer early detection markers

Cooperative amplification of Prussian blue as a signal indicator and functionalized metal-organic framework-based electrochemical biosensor for an ultrasensitive HE4 assay

Human epididymis protein 4 (HE4), a diagnostic biomarker of ovarian cancer, is crucial for monitoring the early stage of the disease. Hence, it is highly important to develop simple, inexpensive, and user-friendly biosensors for sensitive and quantitative HE4 assays. Herein, a new sandwich-type electrochemical immunosensor based on Prussian blue (PB) as a signal indicator and functionalized metal-organic framework nanocompositesas efficient signal amplifiers was fabricated for quantitative analysis of HE4. In principle, ketjen black (KB) and AuNPs modified on TiMOF (TiMOF-KB@AuNPs) could accelerate electron transfer on the electrode surface and act as a matrix for the immobilization of antibodies via cross-linking to improve the determination sensitivity. The PB that covalently binds to labeled antibodies endows the biosensors with intense electrochemical signals. Furthermore, the concentration of HE4 could be indirectly detected by monitoring the electroactivity of PB. Benefiting from the high signal amplification ability of the PB and MOF nanocomposites, this strategy displayed a wide linear range (0.1-80 ng mL-1) and a lower detection limit (0.02 ng mL-1). Hence, this study demonstrated great promise for application in clinical ovarian cancer diagnosis and treatment, and provided a new platform for detecting other cancer biomarkers.

Advancements in protein glycosylation biomarkers for ovarian cancer through mass spectrometry-based approaches

INTRODUCTION

Ovarian cancer, characterized by metastasis and reduced 5-year survival rates, stands as a substantial factor in the mortality of gynecological malignancies worldwide. The challenge of delayed diagnosis originates from vague early symptoms and the absence of efficient screening and diagnostic biomarkers for early cancer detection. Recent studies have explored the intricate interplay between ovarian cancer and protein glycosylation, unveiling the potential significance of glycosylation-oriented biomarkers.

AREAS COVERED

This review examines the progress in glycosylation biomarker research, with particular emphasis on advances driven by mass spectrometry-based technologies. We document milestones achieved, discuss encountered limitations, and also highlight potential areas for future research and development of protein glycosylation biomarkers for ovarian cancer.

EXPERT OPINION

The association of glycosylation in ovarian cancer is well known, but current research lacks desired sensitivity and specificity for early detection. Notably, investigations into protein-specific and site-specific glycoproteomics have the potential to significantly enhance our understanding of ovarian cancer and facilitate the identification of glycosylation-based biomarkers. Furthermore, the integration of advanced mass spectrometry techniques with AI-driven analysis and glycome databases holds the promise for revolutionizing biomarker discovery for ovarian cancer, ultimately transforming diagnosis and improving patient outcomes.

Role of Defects of Carbon Nanomaterials in the Detection of Ovarian Cancer Cells in Label-Free Electrochemical Immunosensors

Developing label-free immunosensors to detect ovarian cancer (OC) by cancer antigen (CA125) is essential to improving diagnosis and protecting women from life-threatening diseases. Four types of carbon nanomaterials, such as multi-wall carbon nanotubes (MWCNTs), vapor-grown carbon fiber (VGCFs), graphite KS4, and carbon black super P (SP), have been treated with acids to prepare a carbon nanomaterial/gold (Au) nanocomposite. The AuNPs@carbon nanocomposite was electrochemically deposited on a glassy carbon electrode (GCE) to serve as a substrate to fabricate a label-free immunosensor for the detection of CA125. Among the four AuNPs@carbon composite, the AuNPs@MWCNTs-based sensor exhibited a high sensitivity of 0.001 µg/mL for the biomarker CA125 through the square wave voltammetry (SWV) technique. The high conductivity and surface area of MWCNTs supported the immobilization of AuNPs. Moreover, the carboxylic (COO-) functional groups in MWCNT improved to a higher quantity after the acid treatment, which served as an excellent support for the fabrication of electrochemical biosensors. The present method aims to explore an environmentally friendly synthesis of a layer-by-layer (LBL) assembly of AuNPs@carbon nanomaterials electrochemical immunoassay to CA125 in a clinical diagnosis at a low cost and proved feasible for point-of-care diagnosis.

Triple Amplification Ratiometric Electrochemical Aptasensor for CA125 Based on H-Gr/SH-β-CD@PdPtNFs

A triple-amplified and ratiometric electrochemical aptasensor for CA125 was designed based on hemin-graphene/SH-β-cyclodextrin@PdPt nanoflower (H-Gr/SH-β-CD@PdPtNF) composites and an exonuclease I (Exo I)-assisted strategy. In the nanocomposite, hemin acts as an internal reference signal owing to the reversible hemin_ox/hemin_red pair. PdPtNFs can significantly improve the electron transfer rate. SH-β-CD can efficiently enrich quercetin probes through host-guest recognition and increase the second indicator signal. In the presence of CA125, due to the specific binding between the aptamer and CA125, the conformational change of dsDNA (designed by the CA125 aptamer and its complementary DNA) results in the release of quercetin embedded in dsDNA. Subsequently, the free quercetin and DNA fragments are enriched on the H-Gr/SH-β-CD@PdPtNF-modified electrode. Thus, an enhanced oxidation peak from quercetin (I_Q) and a reduced peak from hemin (I_hemin) can indicate the same biological identification event. In addition, the recycling amplification of CA125 by Exo I can effectively assist the increase of the quercetin signal. The value of I_Q/I_hemin is linear with the concentration of CA125 in the range from 6.0 × 10^-4 to 1.0 × 10³ ng/mL, and the limit of detection is 1.4 × 10^-4 ng/mL. The recovery of CA125 in human blood serum samples was from 99.2 to 104.4%. The proposed sensor is sensitive and reliable, which provides an avenue for the development of triple amplification and ratiometric signal strategies for detecting tumor markers in clinical diagnostics.

Multiple Biomarker Simultaneous Detection in Serum via a Nanomaterial-Functionalized Biosensor for Ovarian Tumor/Cancer Diagnosis

Ovarian tumors/cancers are threatening women's health worldwide, which demands high-performance detection methods and accurate strategies to effectively detect, diagnose and treat them. Here, we report a nanographene oxide particle-functionalized microfluidic fluorescence biosensor to simultaneously detect four biomarkers, CA125, HE4, CEA and APF, for ovarian tumor/cancer diagnosis. The developed biosensor exhibits good selectivity and a large biomarker detection range with a limit of detection of 0.01 U/mL for CA125 and ~1 pg/mL for HE4, CEA and APF. The current results indicate that (1) the proposed biosensor is a promising tool for the simultaneous detection of multiple biomarkers in ovarian tumors/cancer and (2) CA125 and HE4 are strong indicators, AFP may be helpful, and CEA is a weak biomarker for ovarian tumor/cancer diagnosis. The proposed biosensor would be a potential tool, and an analytical approach for the simultaneous detection of multiple biomarkers will provide a new strategy for the early screening, diagnosis and treatment of ovarian tumors/cancers, as well as other cancers.

Detection of cancer biomarkers CA125 and CA199 via terahertz metasurface immunosensor

The cancer biomarkers including AFP, CEA, CA199 and CA125, are of great importance in the diagnosis, prognostic prediction and recurrence monitoring of malignancies. However, in clinical practical applications, most tumor cancer biomarkers are lack of sensitivity and specificity. In this study, we propose a terahertz (THz) metasurface (MS) immunosensor coupled with gold nanoparticles (AuNPs), which have good biocompatibility and high specific surface area for biomarkers. Firstly, we added AuNPs to the surface of the sensor. And then, the surface is modified with Anti-CA125 or Anti-CA199 to improve the sensitivity and specificity to the target antigen. The biosensor was fabricated using a surface micromachining process and characterized by a THz-time-domain spectroscopy (TDS) system. The sensitivity of the resonance frequency of the sensor to the refractive index was 65 GHz/RIU (refractive index unit). The detection performance of the THz immunosensor was also verified with different concentrations of CA125 and CA199. The experimental results showed that the frequency shift of the resonance peak was linearly related to the concentration of CA125 and CA199. The detection limits for both CA125 and CA199 are 0.01 U/ml, which is better than that of other common methods. Finally, serum samples were collected and detected to explore whether this method is suitable for clinical detection. The results are consistent with the results of antigen recognition. This study proves that the practicability of the THz immunosensor, which potentially provides important techniques and equipment for improving the sensitivity and specificity of cancer biomarkers.

Tumor Biomarker In-Solution Quantification, Standard Production, and Multiplex Detection

The diagnosis and monitoring of cancer have been facilitated by discovering tumor "biomarkers" and methods to detect their presence. Yet, for certain cancers, we still lack sensitive and specific biomarkers or the means to quantify subtle concentration changes successfully. The identification of new biomarkers of disease and improving the sensitivity of detection will remain key to changing clinical outcomes. Patient liquid biopsies (serum and plasma) are the most easily obtained sources for noninvasive analysis of proteins that tumor cells release directly and via extracellular microvesicles and tumor shedding. Therefore, an emphasis on creating reliable assays using serum/plasma and "direct, in-solution" ELISA approaches has built an industry centered on patient protein biomarker analysis. A need for improved dynamic range and automation has resulted in the application of ELISA principles to paramagnetic beads with chemiluminescent or fluorescent detection. In the clinical testing lab, chemiluminescent paramagnetic assays are run on automated machines that test a single analyte, minimize technical variation, and are not limited by serum sample volumes. This differs slightly from the R&D setting, where serum samples are often limiting; therefore, multiplexing antibodies to test multiple biomarkers in low serum volumes may be preferred. This review summarizes the development of historical biomarker "standards", paramagnetic particle assay principles, chemiluminescent or fluorescent biomarker detection advancements, and multiplexing for sensitive detection of novel serum biomarkers.

Effects of Buffer Concentration on the Sensitivity of Silicon Nanobelt Field-Effect Transistor Sensors

In this work, a single-crystalline silicon nanobelt field-effect transistor (SiNB FET) device was developed and applied to pH and biomolecule sensing. The nanobelt was formed using a local oxidation of silicon technique, which is a self-aligned, self-shrinking process that reduces the cost of production. We demonstrated the effect of buffer concentration on the sensitivity and stability of the SiNB FET sensor by varying the buffer concentrations to detect solution pH and alpha fetoprotein (AFP). The SiNB FET sensor was used to detect a solution pH ranging from 6.4 to 7.4; the response current decreased stepwise as the pH value increased. The stability of the sensor was examined through cyclical detection under solutions with different pH; the results were stable and reliable. A buffer solution of varying concentrations was employed to inspect the sensing capability of the SiNB FET sensor device, with the results indicating that the sensitivity of the sensor was negatively dependent on the buffer concentration. For biomolecule sensing, AFP was sensed to test the sensitivity of the SiNB FET sensor. The effectiveness of surface functionalization affected the AFP sensing result, and the current shift was strongly dependent on the buffer concentration. The obtained results demonstrated that buffer concentration plays a crucial role in terms of the sensitivity and stability of the SiNB FET device in chemical and biomolecular sensing.

Active Ratio Test (ART) as a Novel Diagnostic for Ovarian Cancer

Background: Despite substantial effort, there remains a lack of biomarker-based, clinically relevant testing for the accurate, non-invasive diagnostic or prognostic profiling of epithelial ovarian cancers (EOC). Our previous work demonstrated that whilst the inflammatory marker C-X-C motif chemokine ligand 10 (CXCL10) has prognostic relevance in ovarian cancer, its use is complicated by the presence of multiple, N-terminally modified variants, mediated by several enzymes including Dipeptidyl Peptidase 4 (DPP4). Methods: In this study, we provide the first evidence for the “Active Ratio Test” (ART) as a novel method to measure biologically relevant CXCL10 proteoforms in clinical samples. Results: In a cohort of 275 patients, ART accurately differentiated patients with malignant EOCs from those with benign gynaecological conditions (AUC 0.8617) and significantly out-performed CA125 alone. Moreover, ART combined with the measurement of CA125 and DPP4 significantly increased prognostic performance (AUC 0.9511; sensitivity 90.0%; specificity 91.7%; Cohen’s d > 1) for EOC detection. Conclusion: Our data demonstrate that ART provides a useful method to accurately discriminate between patients with benign versus malignant EOC, and highlights their relevance to ovarian cancer diagnosis. This marker combination may also be applicable in broader screening applications, to identify or discriminate benign from malignant disease in asymptomatic women.

Dynamic light scattering and fluorescence dual-signal sensing of cancer antigen-125 via recognition of the polymerase chain reaction product with gold nanoparticle probe

Cancer antigen 125 (CA - 125) is an important biomarker for the diagnosis of ovarian cancer. In this paper, oligonucleotide 5'-GACAGGCCCGAAGGAATAGATAATACGACTCACTATAGGGAGACAAGAATAAACGCTCAA-3' (oligo 1) contains an aptamer of CA - 125, and was designed partly complementary to oligonucleotide 5'-CTCTCTCTCCACCTTCTTCTTTGAGCGTTTATTCTTGTCT-3' (oligo 2). Oligo 1 · oligo 2 was extended with the Klenow fragment (exo^-) polymerase for further polymerase chain reaction (PCR) processes in the presence of two primers: deoxyribose nucleoside triphosphate and Taq polymerase. Single-stranded DNA was produced at two sides of the PCR product by introducing a C₁₈ spacer into the two primers, which could hybridize with AuNPs-DNA probes, investigated by dynamic light scattering and fluorescence. The addition of CA - 125 can interrupt the hybridization between oligo 1 and oligo 2, causing the average diameter of AuNPs-DNA probes to decrease with the increase of CA-125 within the range of 5 fg mL^-1 - 50 ng mL^-1. The linear regression equation of this relationship was D = 430.48-49.60 log₁₀C, with a detection limit of 1.1 fg mL^-1. Fluorescein molecules were modified at the end of the forward primer. The fluorescence intensity of the PCR product can be measured simultaneously, with the fluorescence intensity increasing linearly with the logarithm of CA-125 concentration within a linear range from 10 fg mL^-1 to 50 ng mL^-1, with a detection limit of 1.5 fg mL^-1.

Label-Free Electrochemical Immunosensor for Ultrasensitive Detection of Carbohydrate Antigen 125 Based on Antibody-Immobilized Biocompatible MOF-808/CNT

In this work, a nanocomposite of Zr-trimesic acid MOF (MOF-808) with carbon nanotube (CNT) was synthesized through an in situ formation of MOF-808 on the activated CNT. The synthesized materials were characterized by powder X-ray diffraction, transmission electron microscopy, X-ray photoluminescence spectroscopy, Brunauer-Emmett-Teller, Fourier transform infrared spectroscopy, and Raman spectroscopy. The protein compatible nature with high surface area and electrocatalytic ability of MOF-808 was utilized to construct an immunosensor for ultra low-level detection of the ovarian cancer biomarker, carbohydrate antigen 125 (CA 125). The mutual benefit of each constituent of the MOF-808/CNT composite was capable of producing highly enhanced electrochemical properties. A glassy carbon electrode modified with MOF-808/CNT was used as a platform to fabricate a label-free electrochemical immunosensor. The antibody binding sites of MOF-808/CNT were enriched by functionalization with streptavidin. The immunosensor exhibited two linear determination ranges of 0.001-0.1 and 0.1-30 ng·mL^-1, and the calculated limit of detection was 0.5 pg·mL^-1 (S/N 3). The immunosensor showed excellent reproducibility and selectivity. The patient serum sample analysis was cross-verified with the electrochemiluminescence method with a relative error of 105-110%.

A high-performance microfluidic detection platform to conduct a novel multiple-biomarker panel for ovarian cancer screening

Ovarian cancer is an important leading cause of cancer-related deaths among females, and a single biomarker does not have the sensitivity and specificity required for an effective ovarian cancer screening. Herein, we investigate a high-performance microfluidic detection platform to conduct a novel panel of multiple biomarkers for the early detection of ovarian carcinoma, which include CA125, HE4, OPN, MSLN, Hsp70, CA153, AFP, IL-6, and IL-8 using a microfluidic chip. High-throughput microfluidic chips and graphene oxide-assembled substrate are used to microprint repeatable capture antibody arrays and conduct multiple biomarkers in microscale volume samples. The proposed microfluidic platform achieves an ultralow detection limit of ∼1 pg mL⁻¹ and 0.01 U mL⁻¹ with excellent detection selectivity and a short detection time of 30 min. The analysis of serum biomarkers in 18 ovarian cancer patients and 4 healthy persons indicates a clear subgroup sorting between the high-grade serous ovarian carcinoma, borderline, and benign tumor patients, and healthy persons. The proposed detection platform and the biomarker panel are promising to conduct an early detection of ovarian cancer.

A high-performance microfluidic detection platform is developed to conduct a novel panel of multiple biomarkers for the early detection of ovarian carcinoma, which is promising for the early detection of ovarian cancer.

Recent advancements in fabrication of nanomaterial based biosensors for diagnosis of ovarian cancer: a comprehensive review

Ovarian cancer is commonly diagnosed via determination of biomarkers like CA125, Mucin 1, HE4, and prostasin that can be present in the blood. However, there is a substantial need for less expensive, simpler, and portable diagnostic tools, both for timely diagnosis and management of ovarian cancer. This review (with 101 refs.) discusses various kinds of nanomaterial-based biosensors for tumor markers. Following an introduction into the field, a first section covers different kinds of biomarkers for ovarian cancer including CA125 (MUC16), mucin 1 (MUC1), human epididymis protein 4 (HE4), and prostasin. This is followed by a short overview on conventional diagnostic approaches. A large section is then presented on biosensors for determination of ovarian cancer, with subsections on optical biosensors (fluorimetric, colorimetric, surface plasmon resonance, chemiluminescence, electrochemiluminescence), on electrochemical sensors, molecularly imprinted sensors, paper-based biosensors, microfluidic (lab-on-a-chip) assays, chemiresistive and field effect transistor-based sensors, and giant magnetoresistive sensors. Tables are presented that give an overview on the wealth of methods and materials. A concluding section summarizes the current status, addresses current challenges, and gives an outlook on potential future trends. Graphical abstract Schematic representation of the review covering the advancements in the fabrication of various nanomaterial based biosensors for diagnosis of ovarian cancer.

Introducing graphitic carbon nitride nanosheets as supersandwich-type assembly on porous electrode for ultrasensitive electrochemiluminescence immunosensing

Biomarkers in blood or tissue provide essential information for clinical screening and early disease diagnosis. However, increasing the sensitivity of detecting biomarkers remains a major challenge in a wide variety of electrochemical immunoassays. Herein, we present an electrochemiluminescence (ECL) immunosensing strategy with 1: Nⁿ amplification ratio (target-to-signal probe) for biomarkers detection on a porous gold electrode. The high porosity of the electrode surface provides enough bonding sites for capturing the target biomolecules and thus many DNA labels can be introduced. On the basis of this concept, a great number of graphitic carbon nitride (g-C₃N₄) nanosheets are employed to create a supersandwich-type assembly on a porous electrode via the DNA hybridization process. Furthermore, compared with the traditional sandwich immunoassay (the ratio of target-to-signal probe is 1 : 1), the supersandwich construction can introduce a large number of signal probes, thus resulting in a highly improved sensitivity. The proposed ECL immunosensor exhibits an excellent performance in a concentration range from 0.01 fg mL^-1 to 1 μg mL^-1 with an ultralow detection limit of 0.001 fg mL^-1 (S/N = 3) and excellent selectivity. This sensing strategy could be developed into a real-time assay for the disease-related molecular targets, with many practical applications in biotechnology and life science.

Profiling of Cytokine and Chemokine Responses Using Multiplex Bead Array Technology

Multiplex bead array technology expands upon the principles of the enzyme-linked immunosorbent assay by allowing the simultaneous quantification of a large number of cytokines and chemokines within a single sample. This allows researchers more freedom and opportunities to investigate complex immune responses both in vivo and in vitro. Here we describe and update the detailed assay protocol and technical tips for simultaneous quantification of multiple cytokines and chemokines in mouse biological fluids such as sera, bronchoalveolar lavage fluid, tissue homogenate supernatant, and tissue culture supernatant, using a multiplex bead array assay.

Liquid Crystals: A Novel Approach for Cancer Detection and Treatment

Liquid crystals are defined as the fourth state of matter forming between solid and liquid states. Earlier the applications of liquid crystals were confined to electronic instruments, but recent research findings suggest multiple applications of liquid crystals in biology and medicine. Here, the purpose of this review article is to discuss the potential biological impacts of liquid crystals in the diagnosis and prognosis of cancer along with the risk assessment. In this review, we also discussed the recent advances of liquid crystals in cancer biomarker detection and treatment in multiple cell line models. Cases reviewed here will demonstrate that cancer diagnostics based on the multidisciplinary technology and intriguingly utilization of liquid crystals may become an alternative to regular cancer detection methodologies. Additionally, we discussed the formidable challenges and problems in applying liquid crystal technologies. Solving these problems will require great effort and the way forward is through the multidisciplinary collaboration of physicists, biologists, chemists, material-scientists, clinicians, and engineers. The triumphant outcome of these liquid crystals and their applications in cancer research would be convenient testing for the detection of cancer and may result in treating the cancer patients non-invasively.

Nano-plasmonics and electronics co-integration in CMOS enabling a pill-sized multiplexed fluorescence microarray system

The ultra-miniaturization of massively multiplexed fluorescence-based bio-molecular sensing systems for proteins and nucleic acids into a chip-scale form, small enough to fit inside a pill (∼ 0.1cm3), can revolutionize sensing modalities in-vitro and in-vivo. Prior miniaturization techniques have been limited to focusing on traditional optical components (multiple filter sets, lenses, photo-detectors, etc.) arranged in new packaging systems. Here, we report a method that eliminates all external optics and miniaturizes an entire multiplexed fluorescence system into a 2 × 1 mm2 chip through co-integration for the first time of massively scalable nano-plasmonic multi-functional optical elements and electronic processing circuitry realized in an industry standard complementary-metal-oxide semiconductor (CMOS) foundry process with absolutely 'no change' in fabrication or processing. The implemented nano-waveguide based filters operating in the visible and near-IR realized with the embedded sub-wavelength multi-layer copper-based electronic interconnects inside the chip show for the first time a sub-wavelength surface plasmon polariton mode inside CMOS. This is the principle behind the angle-insensitive nature of the filtering that operates in the presence of uncollimated and scattering environments, enabling the first optics-free 96-sensor CMOS fluorescence sensing system. The chip demonstrates the surface sensitivity of zeptomoles of quantum dot-based labels, and volume sensitivities of ∼ 100 fM for nucleic acids and ∼ 5 pM for proteins that are comparable to, if not better, than commercial fluorescence readers. The ability to integrate multi-functional nano-optical structures in a commercial CMOS process, along with all the complex electronics, can have a transformative impact and enable a new class of miniaturized and scalable chip-sized optical sensors.

A novel algorithm to improve specificity in ovarian cancer detection

BACKGROUND

Measurement of autoantibodies (AAbs) to tumor associated antigens has been proposed to aid in the early detection of ovarian cancer with high specificity. Here we describe a multiplex approach to evaluate selected peptide epitopes of p53 protein, and propose a novel approach to increase specificity and potentially sensitivity for discrimination between healthy women and women with cancerous masses.

MATERIALS AND METHODS

20-mer overlapping peptide epitopes of p53, generated by mapping the complete p53 sequence, were evaluated in a multiplex immunoassay for their detection of serum AAbs in patients with ovarian cancer, using Luminex technology. AAbs to the selected peptides and to p53 full length protein were then detected in a multiplex immunoassay evaluating 359 sera from healthy women and 285 sera from patients with early and late stage ovarian cancer. CA-125 levels were measured in all p53 AAb-positive sera.

RESULTS

We considered the AAb results together to identify sera where both the full length protein and at least one selected peptide epitope were positive and chose cutoffs that reduced false positives from these AAbs to 1/359 samples, improving specificity. Using this combined approach, we could identify 7 AAb-positive patients that were negative for CA-125 (concentrations below 35 IU/mL); this represents 26% of the p53 positive patients in the total population.

CONCLUSION

By detecting p53 AAbs in CA-125-negative sera, we demonstrated that combining measurement of AAbs to the full length p53 protein and one or more selected epitopes can potentially improve sensitivity and specificity for ovarian cancer detection.

Improving cancer detection through combinations of cancer and immune biomarkers: a modelling approach

Background

Early cancer diagnosis is one of the most important challenges of cancer research, since in many cancers it can lead to cure for patients with early stage diseases. For epithelial ovarian cancer (which is the leading cause of death among gynaecologic malignancies) the classical detection approach is based on measurements of CA-125 biomarker. However, the poor sensitivity and specificity of this biomarker impacts the detection of early-stage cancers.

Methods

Here we use a computational approach to investigate the effect of combining multiple biomarkers for ovarian cancer (e.g., CA-125 and IL-7), to improve early cancer detection.

Results

We show that this combined biomarkers approach could lead indeed to earlier cancer detection. However, the immune response (which influences the level of secreted IL-7 biomarker) plays an important role in improving and/or delaying cancer detection. Moreover, the detection level of IL-7 immune biomarker could be in a range that would not allow to distinguish between a healthy state and a cancerous state. In this case, the construction of solution diagrams in the space generated by the IL-7 and CA-125 biomarkers could allow us predict the long-term evolution of cancer biomarkers, thus allowing us to make predictions on cancer detection times.

Conclusions

Combining cancer and immune biomarkers could improve cancer detection times, and any predictions that could be made (at least through the use of CA-125/IL-7 biomarkers) are patient specific.

Highly Sensitive Detection of Protein Biomarkers with Organic Electrochemical Transistors

The analysis of protein biomarkers is of great importance in the diagnosis of diseases. Although many convenient and low-cost electrochemical approaches have been extensively investigated, they are not sensitive enough in the detection of protein biomarkers with low concentrations in physiological environments. Here, this study reports a novel organic-electrochemical-transistor-based biosensor that can successfully detect cancer protein biomarkers with ultrahigh sensitivity. The devices are operated by detecting electrochemical activity on gate electrodes, which is dependent on the concentrations of proteins labeled with catalytic nanoprobes. The protein sensors can specifically detect a cancer biomarker, human epidermal growth factor receptor 2, down to the concentration of 10^-14 g mL^-1 , which is several orders of magnitude lower than the detection limits of previously reported electrochemical approaches. Moreover, the devices can successfully differentiate breast cancer cells from normal cells at various concentrations. The ultrahigh sensitivity of the protein sensors is attributed to the inherent amplification function of the organic electrochemical transistors. This work paves a way for developing highly sensitive and low-cost biosensors for the detection of various protein biomarkers in clinical analysis in the future.

An amplified comparative fluorescence resonance energy transfer immunosensing of CA125 tumor marker and ovarian cancer cells using green and economic carbon dots for bio-applications in labeling, imaging and sensing

CA125, is a marker in the clinical diagnosis of several cancers and currently is the best serum-based tumor marker for ovarian cancer. Here, we developed an ultrasensitive antibody-ssDNA aptamer sandwich-type fluorescence immunosensor for CA125 detection. Based on a novel signal amplification strategy the carbon dots (CDs) functionalized with aptamer (CD-aptamer) used as detection probe and PAMAM-Dendrimers/AuNPs was used for covalent attachment of CA125-antibody and completing the sandwich assay method. By measuring of fluorescence resonance energy transfer (FRET) signals between CDs and AuNPs as nanoquenchers, the fluorescence signal quenched during sandwich complex formed between anti-CA125, CA125 and CDs-Aptamer and decreasing of fluorescence response signal is related to CA125 concentrations. Under optimal conditions, the immunosensor exhibited an extremely low calculated detection limit of 0.5fg/mL with wide linear range 1.0fg/mL to 1.0ng/mL of CA 125. The application of the immunosensor for CA125 detection in serum samples and measuring of ovarian-cancer cells was also investigated. The immunosensor revealed good sensitivity and specificity with ovarian cell concentrations from 2.5×10³ to 2×10⁴cells/mL with correlation coefficient of 0.9937 and detection limit of 400cells/mL (4 cell in 10μL), indicating potential application of immunosensor in clinical monitoring of tumor biomarkers. Furthermore, the cell viability was not changed upon treatment with CDs probe during 24h, showing the low cytotoxicity of the probe. More importantly, CDs-antibody hybrid was achieved in selective imaging of the cancer cells over the OVCAR-3 line cells, implying its potential applications in biosensing, as well as in cancer diagnosis.

Selenium-Binding Protein 1 (SBP1) autoantibodies in ovarian disorders and ovarian cancer

Infertility is a risk factor for ovarian cancer (OvCa). The goal was to determine if antibodies to selenium-binding protein 1 (SBP1), an autoantibody we identified in patients with premature ovarian failure (POF), occurs in both infertility and OvCa patients, and thus could be associated with preneoplasia. Anti-SBP1 was measured by immunoassay against recombinant SBP1, in sera from OvCa (n = 41), infertility (n = 92) and control (n = 87) patients. Infertility causes were POF, unexplained, irregular ovulation or endometriosis. The percent of anti-SBP1-positive sera was higher in POF (P = 0.02), irregular ovulation (P = 0.001), unexplained causes (P = 0.02), late (III-IV)-stage OvCa (P = 0.02) but was not significant in endometriosis, benign ovarian tumors/cysts, early stage (I-II) OvCa or uterine cancer compared to healthy controls. Anti-SBP1 was significantly higher in women with serous (P = 0.04) but not non-serous (P = 0.33) OvCa compared to controls. Also, we determined if anti-SBP1 was associated with CA125 or anti-TP53, markers often studied in OvCa. Anti-TP53 and CA125 were measured by established immunoassays. The ability of anti-SBP1 alone to discriminate infertility or OvCa from controls or when combined with anti-TP53 and CA125, to identify OvCa was evaluated by comparing the area under the curve (AUC) in ROC analysis. Anti-SBP1 alone discriminated infertility (AUC = 0.7; P = 0.001) or OvCa (AUC = 0.67; P = 0.03) from controls. The sensitivity and specificity of OvCa identification was increased by combining CA125, anti-TP53 and anti-SBP1 (AUC = 0.96). Therefore, anti-SBP1 occurs in infertile women with POF, ovulatory disturbances or unexplained infertility and in serous OvCa. This suggests an autoimmune process is associated with the development of serous OvCa.

CMOS biosensors for in vitro diagnosis - transducing mechanisms and applications

Complementary metal oxide semiconductor (CMOS) technology enables low-cost and large-scale integration of transistors and physical sensing materials on tiny chips (e.g., <1 cm²), seamlessly combining the two key functions of biosensors: transducing and signal processing. Recent CMOS biosensors unified different transducing mechanisms (impedance, fluorescence, and nuclear spin) and readout electronics have demonstrated competitive sensitivity for in vitro diagnosis, such as detection of DNA (down to 10 aM), protein (down to 10 fM), or bacteria/cells (single cell). Herein, we detail the recent advances in CMOS biosensors, centering on their key principles, requisites, and applications. Together, these may contribute to the advancement of our healthcare system, which should be decentralized by broadly utilizing point-of-care diagnostic tools.

N-glycan MALDI Imaging Mass Spectrometry on Formalin-Fixed Paraffin-Embedded Tissue Enables the Delineation of Ovarian Cancer Tissues

Ovarian cancer is a fatal gynaecological malignancy in adult women with a five-year overall survival rate of only 30%. Glycomic and glycoproteomic profiling studies have reported extensive protein glycosylation pattern alterations in ovarian cancer. Therefore, spatio-temporal investigation of these glycosylation changes may unearth tissue-specific changes that occur in the development and progression of ovarian cancer. A novel method for investigating tissue-specific N-linked glycans is using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) on formalin-fixed paraffin-embedded (FFPE) tissue sections that can spatially profile N-glycan compositions released from proteins in tissue-specific regions. In this study, tissue regions of interest (e.g. tumor, stroma, adipose tissue and necrotic areas) were isolated from FFPE tissue sections of advanced serous ovarian cancers (n = 3). PGC-LC-ESI-MS/MS and MALDI-MSI were used as complementary techniques to firstly generate structural information on the tissue-specific glycans in order to then obtain high resolution images of the glycan structure distribution in ovarian cancer tissue. The N-linked glycan repertoires carried by the proteins in these tissue regions were structurally characterized for the first time in FFPE ovarian cancer tissue regions, using enzymatic peptide-N-glycosidase F (PNGase F) release of N-glycans. The released glycans were analyzed by porous graphitized carbon liquid chromatography (PGC-LC) and collision induced electrospray negative mode MS fragmentation analysis. The N-glycan profiles identified by this analysis were then used to determine the location and distribution of each N-glycan on FFPE ovarian cancer sections that were treated with PNGase F using high resolution MALDI-MSI. A tissue-specific distribution of N-glycan structures identified particular regions of the ovarian cancer sections. For example, high mannose glycans were predominantly expressed in the tumor tissue region whereas complex/hybrid N-glycans were significantly abundant in the intervening stroma. Therefore, tumor and non-tumor tissue regions were clearly demarcated solely on their N-glycan structure distributions.

The Use of Breast Magnetic Resonance Imaging Parameters to Identify Possible Signaling Pathways of a Serum Biomarker, HE4

OBJECTIVES

This study aimed to investigate the relationship between breast magnetic resonance imaging (MRI) parameters; clinical features such as age, tumor diameter, N, T, and TNM stages; and serum human epididymis protein 4 (HE4) levels in patients with breast carcinoma and use this as a means of estimating possible signaling pathways of the biomarker, HE4.

METHODS

Thirty-seven patients with breast cancer were evaluated by breast MRI and serum HE4 levels before therapy. Correlations between parameters including age, tumor diameter T and N, dynamic curve type, enhancement ratio (ER), slope washin (S-WI), time to peak (TTP), slope washout (S-WO), and the serum level of HE4 were investigated statistically. Human epididymis protein 4 levels of early and advanced stage of disease were also compared statistically.

RESULTS

Breast MRI parameters showed correlation to serum HE4 levels and correlations were statistically significant. Of these MRI parameters, S-WI had higher correlation coefficient than the others. Human epididymis protein 4 levels were not statistically different in early and advanced stage of disease.

CONCLUSIONS

High correlation with MRI parameters related to neoangiogenesis may indicate signaling pathway of HE4.

Human epididymis protein 4 expression positively correlated with miR-21 and served as a prognostic indicator in ovarian cancer

Ovarian cancer is the most common cause of gynecological malignancy-related mortality. Human epididymis protein 4 (HE4) is a useful biomarker for ovarian cancer when either used alone or in combination with carbohydrate antigen 125 (CA125). What is more, aberrant expression of microRNA-21 (miR-21) has been shown to be involved in oncogenesis, but the relationship between miR-21 and HE4 in ovarian cancer is not clear. Tumor and adjacent tumor tissues from 43 patients with ovarian cancer were examined. Real-time polymerase chain reaction (RT-PCR) was used to detect the expression of HE4 in the carcinoma and adjacent tissues. The associations between HE4 and tumor biological characters were discussed. TaqMan(®) MicroRNA (miRNA) assays were employed to detect the expression of miR-21 in the ovarian carcinoma. In ovarian cancer, the expression of HE4 messenger RNA (mRNA) in cancer tissues was higher than adjacent tumor tissues (P < 0.0001), which was 1.299-fold of adjacent tumor tissues. And, the expression of miR-21 was also up-regulated which was significantly different in the ovarian cancer (the positive rate was 76.74 %). There was a significantly positive correlation between miR-21 and HE4 expression (r = 0.283 and P = 0.066 for HE4 mRNA, r = 0.663 and P < 0.0001 for serum HE4). There was also a significant correlation between miR-21 and tumor grade (r = 0.608, P < 0.0001). Significantly, patients with recent recurrence (less than 6 months, n = 17) have a higher miR-21 expression than those with no recent recurrence. Therefore, HE4 and miR-21 may play an important role in the development and progression of ovarian cancer and they may serve as prognostic indicators in ovarian cancer.

Functional characterizations of interactive recombinant PTEN–silica nanoparticles for potential biomedical applications

Nanosystem mediated successful stabilization and delivery of functional recombinant PTEN.

Evaluating Serum Markers for Hormone Receptor-Negative Breast Cancer

INTRODUCTION

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death in females worldwide. Death rates have been declining, largely as a result of early detection through mammography and improved treatment, but mammographic screening is controversial because of over-diagnosis of breast disease that might not require treatment, and under-diagnosis of cancer in women with dense breasts. Breast cancer screening could be improved by pairing mammography with a tumor circulating marker, of which there are currently none. Given genomic similarities between the basal breast cancer subtype and serous ovarian cancer, and given our success in identifying circulating markers for ovarian cancer, we investigated the performance in hormone receptor-negative breast cancer detection of both previously identified ovarian serum markers and circulating markers associated with transcripts that were differentially expressed in breast cancer tissue compared to healthy breast tissue from reduction mammaplasties.

METHODS

We evaluated a total of 15 analytes (13 proteins, 1 miRNA, 1 autoantibody) in sera drawn at or before breast cancer surgery from 43 breast cancer cases (28 triple-negative-TN-and 15 hormone receptor-negative-HRN-/ HER2-positive) and 87 matched controls.

RESULTS

In the analysis of our whole cohort of breast cancer cases, autoantibodies to TP53 performed significantly better than the other selected 14 analytes showing 25.6% and 34.9% sensitivity at 95% and 90% specificity respectively with AUC: 0.7 (p<0.001). The subset of 28 TN cancers showed very similar results. We observed no correlation between anti-TP53 and the 14 other markers; however, anti-TP53 expression correlated with Body-Mass-Index. It did not correlate with tumor size, positive lymph nodes, tumor stage, the presence of metastases or recurrence.

CONCLUSION

None of the 13 serum proteins nor miRNA 135b identified women with HRN or TN breast cancer. TP53 autoantibodies identified women with HRN breast cancer and may have potential for early detection, confirming earlier reports. TP53 autoantibodies are long lasting in serum but may be affected by storage duration. Autoantibodies to TP53 might correlate with Body-Mass-Index.

Identification of novel candidate plasma metabolite biomarkers for distinguishing serous ovarian carcinoma and benign serous ovarian tumors

OBJECTIVE

Serous ovarian carcinoma (OC) represents a leading cause of cancer-related death among U.S. women. Non-invasive tools have recently emerged for discriminating benign from malignant ovarian masses, but evaluation remains ongoing, without widespread implementation. In the last decade, metabolomics has matured into a new avenue for cancer biomarker development. Here, we sought to identify novel plasma metabolite biomarkers to distinguish serous ovarian carcinoma and benign serous ovarian tumor.

METHODS

Using liquid chromatography-mass spectrometry, we conducted global and targeted metabolite profiling of plasma isolated at the time of surgery from 50 serous OC cases and 50 serous benign controls.

RESULTS

Global lipidomics analysis identified 34 metabolites (of 372 assessed) differing significantly (P<0.05) between cases and controls in both training and testing sets, with 17 candidates satisfying FDR q<0.05, and two reaching Bonferroni significance. Targeted profiling of ~150 aqueous metabolites identified a single amino acid, alanine, as differentially abundant (P<0.05). A multivariate classification model built using the top four lipid metabolites achieved an estimated AUC of 0.85 (SD=0.07) based on Monte Carlo cross validation. Evaluation of a hybrid model incorporating both CA125 and lipid metabolites was suggestive of increased classification accuracy (AUC=0.91, SD=0.05) relative to CA125 alone (AUC=0.87, SD=0.07), particularly at high fixed levels of sensitivity, without reaching significance.

CONCLUSIONS

Our results provide insight into metabolic changes potentially correlated with the presence of serous OC versus benign ovarian tumor and suggest that plasma metabolites may help differentiate these two conditions.

Accuracy of serum human epididymis protein 4 in ovarian cancer diagnosis: a systematic review and meta-analysis

OBJECTIVE

A systematic review was performed to estimate the accuracy of human epididymis protein 4 (HE4) assay in the diagnosis of ovarian tumors.

METHODS

A comprehensive search of the MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials, IBECS, BIOSIS, Web of Science, SCOPUS, congress abstracts, and Grey literature (Google scholar; British Library) from January 1990 to April 2013 was conducted. Studies that evaluated HE4 levels for the diagnosis of ovarian tumors and compared them with paraffin-embedded sections as the diagnostic standard were included.

RESULTS

Forty-five studies were analyzed, which included 10,671 women and 3946 ovarian cancer cases. The pooled sensitivity for the diagnosis of borderline tumors or ovarian cancer was 78% (95% confidence interval, 77%-79%), and the specificity was 86% (95% confidence interval, 85%-87%). Summary receiver operating characteristic curves were constructed. For malignant and borderline ovarian tumors versus benign lesions, the area under the curve was 0.916. Besides the overall analysis, stratification was performed in premenopause and postmenopause, early and late stages, and for accuracy by enzyme-linked immunosorbent assay and chemiluminescence microparticle immuno assay.

CONCLUSIONS

A HE4 level is a useful preoperative test for predicting the benign or malignant nature of pelvic masses.

Surface modification of alignment layer by ultraviolet irradiation to dramatically improve the detection limit of liquid-crystal-based immunoassay for the cancer biomarker CA125

Liquid crystal (LC)-based biosensing has attracted much attention in recent years. We focus on improving the detection limit of LC-based immunoassay techniques by surface modification of the surfactant alignment layer consisting of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DMOAP). The cancer biomarker CA125 was detected with an array of anti-CA125 antibodies immobilized on the ultraviolet (UV)-modified DMOAP monolayer. Compared with a pristine counterpart, UV irradiation enhanced the binding affinity of the CA125 antibody and reproducibility of immunodetection in which a detection limit of 0.01 ng∕ml for the cancer biomarker CA125 was achieved. Additionally, the optical texture observed under a crossed polarized microscope was correlated with the analyte concentration. In a proof-of-concept experiment using CA125-spiked human serum as the analyte, specific binding between the CA125 antigen and the anti-CA125 antibody resulted in a distinct and concentration-dependent optical response despite the high background caused by nonspecific binding of other biomolecules in the human serum. Results from this study indicate that UVmodification of the alignment layer, as well as detection with LCs of large birefringence, contributes to the enhanced performance of the label-free LC-based immunodetection, which may be considered a promising alternative to conventional label-based methods.

HE4 in the differential diagnosis of ovarian masses

Ovarian masses, a common finding among pre- and post-menopausal women, can be benign or malignant. Ovarian cancer is the leading cause of death from gynecologic malignancy among women living in industrialized countries. According to the current guidelines, measurement of CA125 tumor marker remains the gold standard in the management of ovarian cancer. Recently, HE4 has been proposed as emerging biomarker in the differential diagnosis of adnexal masses and in the early diagnosis of ovarian cancer. Discrimination of benign and malignant ovarian tumors is very important for correct patient referral to institutions specialized in care and management of ovarian cancer. Tumor markers CA125 and HE4 are currently incorporated into the "Risk of Ovarian Malignancy Algorithm" (ROMA) with menopausal status for discerning malignant from benign pelvic masses. The availability of a good biomarker such as HE4, closely associated with the differential and early diagnosis of ovarian cancer, could reduce medical costs related to more expensive diagnostic procedures. Finally, it is important to note that HE4 identifies platinum non-responders thus enabling a switch to second line chemotherapy and improved survival.

Human epididymis protein 4 inhibits proliferation of human ovarian cancer cells via the mitogen-activated protein kinase and phosphoinositide 3-kinase/AKT pathways

OBJECTIVES

Human epididymis protein 4 (HE4) is a promising novel biomarker for the detection of epithelial ovarian cancer (EOC). The role of HE4 in EOC tumorigenesis is unclear. This study investigated the cellular and molecular mechanisms of HE4 in ovarian cancer cell proliferation.

METHODS

We generated HE4-overexpressing SKOV3 cells and silenced HE4 gene expression in SKOV3.ip1 cells. We used the cell counting kit 8 assay to evaluate cell proliferation and Western blotting to analyze the expression of proliferation- and apoptosis-associated proteins such as Bax, Bcl-2, and caspase 3.

RESULTS

Overexpression of HE4 in SKOV3, an ovarian carcinoma cell line, inhibited cell proliferation, In contrast, HE4 silencing in SKOV3.ip1 cells promoted cell proliferation; however, conditioned medium containing HE4 and human recombinant HE4 protein had no effect on proliferation in both SKOV3 and SKOV3.ip1 cells. Human epididymis protein 4 inhibited MEK, extracellular signal-regulating kinase 1/2, and AKT phosphorylation but promoted c-Jun N-terminal protein kinase 1/2/3 and c-JUN phosphorylation; however, p38 phosphorylation was impaired in HE4-overexpressing and silenced cells. Human epididymis protein 4 had no effect on epidermal growth factor receptor phosphorylation or on the apoptosis-associated proteins Bax, Bcl-2, and caspase 3.

CONCLUSIONS

Human epididymis protein 4 might play a protective role in the progression of EOC by inhibiting cell proliferation. Antiproliferative activity was mediated by intracellular HE4 and not the secreted protein. Human epididymis protein 4 might inhibit cell proliferation by regulating the mitogen-activated protein kinase and phosphoinositide 3-kinase/AKT signal transduction pathways in vitro.

Profiling of cytokine and chemokine responses using multiplex bead array technology

Multiplex bead array technology expands upon the principles of the enzyme-linked immunosorbent assay by allowing the simultaneous quantification of a large number of cytokines and chemokines within a single sample. This allows for the researcher more freedom to investigate complex immune responses both in vivo and in vitro. Here we describe the detailed assay protocol and technical tips for simultaneous quantification of multiple cytokines and chemokines in mouse biological fluids such as sera, bronchoalveolar lavage fluid, tissue homogenate supernatant, and tissue culture supernatant, using a multiplex bead array assay.

Recent technical strategies to identify diagnostic biomarkers for ovarian cancer

Ovarian cancer is the fifth leading cause of cancer deaths among North American women. Regrettably, there is currently no reliable circulating biomarker that can detect ovarian cancer in its early stages. The CA125 biomarker is very useful for treatment response monitoring, but its sensitivity is very low for early detection. Thus, there is an urgent need for the identification of new circulating biomarkers/panel of biomarkers that could be used to diagnose ovarian cancer before it becomes clinically detectable and advanced. Unfortunately, the strategies used in the past years to identify such biomarkers have not led to any outstanding candidate. This review summarizes the different approaches used in the last decade and suggests which strategies should be adopted in the near future in order to lead to the successful identification of new ovarian cancer diagnostic biomarkers.

Detection of the ovarian cancer biomarker CA-125 using chemiluminescence resonance energy transfer to graphene quantum dots

A cancer biomarker immuno-sensor has been developed by utilizing the chemiluminescence resonance energy transfer to graphene quantum dots.

Label-free immunodetection of the cancer biomarker CA125 using high-Δn liquid crystals

A label-free and array-based optical liquid-crystal (LC) immunodetection technique for the detection of CA125 antigen, a protein biomarker most frequently used for ovarian cancer detection, was demonstrated with a nematic LC with larger birefringence (Δn) to promote sensitivity in detecting biomolecules. The LC-based immunodetection offers an alternative and sensitive approach for the detection of biomarker proteins, with the potential of replacing conventional immunoassays used in biochemical studies and clinical laboratories.

Serum soluble mesothelin-related peptide (SMRP): a potential diagnostic and monitoring marker for epithelial ovarian cancer

PURPOSE

To explore the potential and diagnostic performance of soluble mesothelin-related peptide (SMRP) as a tumor marker for epithelial ovarian cancer (EOC).

METHODS

Sera were obtained from 78 EOC patients, 84 benign ovarian tumor patients, 58 healthy volunteers, and 22/78 EOC patients 1 week after surgery. SMRP levels and diagnostic performance were assessed by ELISA using the MESOMARK kit. The combination of SMRP and CA125 in the diagnosis of EOC was assessed.

RESULTS

SMRP concentrations were higher in EOC patients than in benign tumor patients and healthy volunteers, and SMRP levels were shown to decrease in EOC patients after surgery. Histological EOC subtypes showed significant differences in SMRP levels. Stage III-IV patients had a higher level of SMRP than stage I-II patients (P < 0.001). Elevated SMRP levels were also found in higher grade tumors (P < 0.001). The receiver operating characteristic curve for SMRP was 0.891. The best statistical cut-off for SMRP was 1.3109 nM, with 0.821 sensitivity and 0.979 specificity. When compared with CA125, SMRP performed better in specificity, omission diagnostic rate, positive predictive value, and correction rate, but worse for sensitivity and negative predictive value. The combination of SMRP and CA125 gave a sensitivity of 98.4 % and a specificity of 88.9 %.

CONCLUSION

Serum SMRP is a promising marker for the diagnosis and monitoring of EOC, especially in combination with CA125.