Detection Of Cancer Antigen Research Articles

A label-free electrochemical immunosensor for CA125 detection based on CMK-3(Au/Fc@MgAl-LDH)n multilayer nanocomposites modification.

A label-free electrochemical immunosensor was constructed for cancer antigen 125 (CA125) detection based on multiple-enlargement means of layer-by-layer (LBL) assembly of ordered mesoporous carbon (CMK-3), gold nanoparticles (Au NPs) and MgAl layered double hydroxides containing ferrocenecarboxylic acid (Fc@MgAl-LDH). A CMK-3(Au/Fc@MgAl-LDH)n multilaminate nanocomposites was designed using technology of LBL self-assembly among negatively charged Au NPs, positively charged CMK-3 and Fc@MgAl-LDH nanosheets. The CMK-3(Au/Fc@MgAl-LDH)n multilaminate nanocomposites was used as carriers to increase the immobilization of antibody and the number of loading Fc, conductors to strengthen conductivity and enhancers to amplify signal of Fc step-by-step. Besides, this special and excellent way of LBL assembly can immensely amplify the signal of immunosensor and more immobilize the biomolecules, and label-free method is a more simple the measuring way and the procedure. The immunosensor displayed a wider linear range of 0.01 Uml-1-1000 Uml-1 and a lower detection limit of 0.004 Uml-1. Therefore, the sensor can stablely and accurately be applied for CA125 detection in clinical cancer diagnosis.

Smartphone-based electrochemical system with multi-walled carbon nanotubes/thionine/gold nanoparticles modified screen-printed immunosensor for cancer antigen 125 detection

In the paper, a smartphone-based electrochemical system with differential pulse voltammetry (DPV) measurement was developed for cancer antigen 125 (CA125) detection. The system was composed of screen-printed immunosensor, miniaturized electrochemical detector and Android smartphone. Combined with multi-walled carbon nanotubes (MWCNTs)/ thionine (Thi)/ gold nanoparticles (AuNPs) modified screen-printed immunosensor, miniaturized electrochemical detector realized high accuracy detection of CA125. The datum were transmitted to Android smartphone through Bluetooth. The detector was powered by audio jack of smartphone, which also used 3.3 V button cell and USB as additional power supply. Android application (APP) running on a smartphone served to control detection process and show detection results. The experimental results indicated that there had good linear relationship between DPV peak currents and the logarithm of CA125 concentrations in the range from 1.3 U mL−1 to 260 U mL−1. The limit of detection (LOD) was 2 mU mL−1. The smartphone-based electrochemical system was also evaluated for the analysis of human serum sample. The detection results showed good agreement with the Roche electrochemicalluminescenceimmunoassay (ECLIA) tests. The proposed system provided a new method for tumor marker detection in remote medicine centre or developing area.

Simultaneous detection of CA15-3 and PGRMC1 on a microfluidic chip for early diagnosis of breast cancer

Simultaneous, rapid, and quantitative detection of multiple tumor markers is extremely important for the prevention and early diagnosis of cancers. In this study, we established a microfluidic-based indirect competitive chemiluminescence enzyme immunoassay for simultaneous detection of cancer antigen 15-3 (CA15-3) and progesterone receptor membrane components 1 (PGRMC1) for diagnosis of breast cancer. CA15-3 and PGRMC1 could be simultaneously detected on the chip. On the chip, the linear ranges of CA15-3 and PGRMC1 were 10 pg/mL–100 ng/mL and 20 pg/mL–358 ng/mL, respectively, whereas the limits of detection (LOD) of CA15-3 and PGRMC1 were 3 pg/mL and 5 pg/mL, respectively. Compared with the enzyme-linked immunosorbent assay (ELISA, LOD = 20 pg/mL for CA15-3; LOD = 10 pg/mL for PGRMC1), our method could simultaneously detect multiple samples with higher sensitivity, which could greatly improve the detection efficiency and meet the requirement for early diagnosis of breast cancer.

Boron nitride nanosheet modified label-free electrochemical immunosensor for cancer antigen 125 detection

In this presented study, a new boron nitride nanosheets modified label-free electrochemical immunosensors were prepared for early detection of cancer antigen 125 (CA125). To aim for, boron nitride (BN) nanosheets were synthesized by conventional sonication-assisted method and then characterized. BN nanosheets were used for the surface modification of the working electrode of the screen-printed electrode (SPE). Anti CA125 antibody was then directly immobilized onto the electrode surface due to its natural affinity towards BN nanosheets. Modified electrodes were blocked with BSA and finally protected with Nafion. The newly synthesized label-free immunosensor demonstrated good detection properties to CA125 with a linear range of 5–100 U and a detection limit of 1.18 U/mL. The developed immunosensor also showed excellent reproducibility, selectivity, and stability profiles. Additionally, this immunosensor was successfully used for the detection of CA125 in artificial human serum samples along with the interfering agents. Also, it is expected that the prepared immunosensor should carry the good potential for point-of-care diagnosis in real cases.

An Ultrasensitive Biosensor for Detection of Femtogram Levels of the Cancer Antigen AGR2 Using Monoclonal Antibody Modified Screen-Printed Gold Electrodes.

The detection of cancer antigens is a major aim of cancer research in order to develop better patient management through early disease detection. Many cancers including prostate, lung, and ovarian secrete a protein disulfide isomerase protein named AGR2 that has been previously detected in urine and plasma using mass spectrometry. Here we determine whether a previously developed monoclonal antibody targeting AGR2 can be adapted from an indirect two-site ELISA format into a direct detector using solid-phase printed gold electrodes. The screen-printed gold electrode was surface functionalized with the anti-AGR2 specific monoclonal antibody. The interaction of the recombinant AGR2 protein and the anti-AGR2 monoclonal antibody functionalized electrode changed its electrochemical impedance spectra. Nyquist diagrams were obtained after incubation in an increasing concentration of purified AGR2 protein with a range of concentrations from 0.01 fg/mL to 10 fg/mL. In addition, detection of the AGR2 antigen can be achieved from cell lysates in medium or artificial buffer. These data highlight the utility of an AGR2-specific monoclonal antibody that can be functionalized onto a gold printed electrode for a one-step capture and quantitation of the target antigen. These platforms have the potential for supporting methodologies using more complex bodily fluids including plasma and urine for improved cancer diagnostics.

Gold-silver alloy film based surface plasmon resonance sensor for biomarker detection.

In this study, we developed a gold‑silver alloy film based surface plasmon resonance (AuAg-SPR) sensor with wavelength interrogation to detect cancer antigen 125 (CA125) using a sandwich immunoassay. We first theoretically simulated the sensitivity of conventional gold film based SPR (Au-SPR) sensor and AuAg-SPR sensor, and conducted a series of experiments to investigate the sensitive characteristics of AuAg-SPR sensor, including the angle and refractive index (RI) sensitivity. We then conducted CA125 detection experiments on these two types of sensors. The results demonstrated that the limit of detection (LOD) of CA125 on the AuAg-SPR sensor was 0.1U/mL (0.8ng/mL) based on its direct reaction with an immobilised antibody, which was two orders of magnitude lower than that of the Au-SPR sensor (10U/mL). The total changes in the resonance wavelength (∆λR) of the former were 1.7-fold those of the latter. The volume fractions of the adsorbates (fad) and effective RIs (nadlayer) in each adlayer were then calculated and the effect of the antibody size on the detection results was analysed. The AuAg-SPR sensors had a higher sensitivity than the conventional Au-SPR sensors for detecting CA125 due to their electric field characteristics. Therefore, these will have better application prospects.

Value of ultrasound combined with serum CA125, CA199 and CEA in the differential diagnosis of ovarian benign and malignant tumors

Objective To investigate the diagnostic values of ultrasonography combined with serum cancer antigen 125 (CA125), serum carbohydrate antigen 199 (CA199), serum carcinoembryonic antigen (CEA) in ovarian malignant tumors. Methods From November 2015 to December 2017, 140 patients with ovarian cancer admitted to the hospital were selected as subjects, and ultrasound examination was carried out with IU22 ultrasound diagnostic instrument. The patients were divided into 92 cases of benign ovarian tumors and 48 cases of malignant ovarian tumors through pathological diagnosis. The serum CA125, CA199 and CEA of all patients were detected by automatic biochemical analyzer, and receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of four combined detection in ovarian malignancies. Results The coincidence rate of ultrasound diagnosis in ovarian benign tumor patients was significantly higher than that in ovarian cancer patients (P<0.05). The levels of serum CA125, CA199 and CEA in benign ovarian tumors were significantly lower than those in malignant ovarian tumors (P<0.05), and the levels of serum CA125, CA199 and CEA in patients with stage Ⅰ to Ⅱ were significantly lower than those in stage Ⅲ to Ⅳ (P<0.05). The area of serum CA125, CA199 and CEA under the ROC curve was 0.788, 0.750 and 0.708, respectively. The boundary points of diagnosis were 50.61 U/ml, 36.47 U/ml and 4.32 ng/ml, respectively. The area under the combined diagnosis curve of the serum CA125, CA199 and CEA was 0.832. The sensitivity, specificity and accuracy of the combined detection were higher than that of single index detection and serum combined detection. Conclusions Ultrasound combined with serum CA125, CA199 and CEA levels detection can improve the sensitivity, specificity and accuracy of diagnosis of ovarian benign and malignant tumors, which has certain clinical value. Key words: Ultrasonography; CA125; CA199; Carcinoembryonic antigen; Ovarian neoplasms

A novel electrochemical immunosensor for ultrasensitive detection of CA125 in ovarian cancer

In the current study, we report on the design and development of a novel electrochemical immunosensor for the detection of cancer antigen 125 (CA125) oncomarker. Polyamidoamine/gold nanoparticles (PAMAM/AuNPs) were used to increase the conductivity and enhance the number of antibodies (Abs) immobilized on the electrode surface. Three-dimensional reduced graphene oxide-multiwall carbon nanotubes (3DrGO-MWCNTs) were used to modify the glassy carbon electrode to improve the electrode conductivity and specific surface area. Ab and toluidine blue attached to O-succinyl-chitosan-magnetic nanoparticles (Suc-CS@MNPs) as a tracer. The poor solubility of chitosan (CS) was improved by succinic anhydride using a novel modification method. Under optimum condition, the developed immunosensor exhibited a wide linear range (0.0005–75 U/mL) and an excellent limit of detection around 6 μU/mL. The reliability of the engineered immunosensor in detecting CA125 was verified by standard addition recovery method, which was further compared to enzyme-linked immunosorbent assay (ELISA). The proposed immunosensor exhibited excellent stability, high selectivity and sensitivity, and good reproducibility. Based on the great performance of the engineered immunosensor, it is proposed as a robust and reliable diagnostic tool for the detection of CA125 in the clinic.

The clinical value of the combined detection of sEGFR, CA125 and HE4 for epithelial ovarian cancer diagnosis.

This study aims to investigate the clinical value of combined detection of serum soluble epidermal growth factor receptor (sEGFR), cancer antigen 125 (CA125), and human epididymis protein 4 (HE4) in the diagnosis of epithelial ovarian cancer (EOC). From December 2017 to October 2018, the serum samples were obtained from the Affiliated Hospital of Xuzhou Medical University, with 30 patients as EOC group, 30 patients with benign ovarian neoplasms as benign group, and 17 healthy subjects as healthy group. Besides, among 30 EOC patients, 9 serum samples were obtained from pre-operative and post-operative EOC patients. The levels of serum sEGFR were detected by enzyme-linked immunosorbent assay (ELISA), while CA125 and HE4 were detected by enhanced chemiluminescence immunoassay (ECLIA). The diagnostic value was evaluated by receiver operating characteristic (ROC) curve analysis. The levels of serum sEGFR, CA125, and HE4 in EOC group were significantly higher than those in benign group (p<0.05) and healthy group (p<0.05). When using a single tumor marker, the CA125 shows the highest sensitivity (93.30%) and HE4 shows the highest specificity (97.87%). The specificity of combined detection of serum sEGFR, CA125, and HE4 was 100%, which was significantly higher than that using a single tumor marker. The area under the ROC curve (AUC) of combined detection of serum sEGFR, CA125, and HE4 (0.965) was much higher than that of the single detection and higher than that of combined detection of CA125 and HE4 (0.940). Moreover, the level of serum sEGFR in post-operative EOC group was significantly lower than that in the corresponding pre-operative EOC group (p<0.05). Our study shows that combined detection of serum sEGFR, CA125, and HE4 increases the specificity and efficiency in EOC diagnosis, indicating that sEGFR could be a potential biomarker for the diagnosis and prognosis of EOC.

A paper-based electrochemical immunosensor with reduced graphene oxide/thionine/gold nanoparticles nanocomposites modification for the detection of cancer antigen 125

A paper-based electrochemical immunosensor was developed for the detection of cancer antigen 125 (CA125) by screen-printing technique. The reduced graphene oxide/thionine/gold nanoparticles (rGO/Thi/AuNPs) nanocomposites were compounded and coated onto the working electrode of immunosensor for CA125 antibody (anti-CA125) immobilization and detection signal amplification. The detection principle was based on the fact that the immunocomplex formed by specify binding of CA125 antibody and antigen could reduce the current response of thionine, which was proportional to the corresponding concentration of CA125 antigen. The immunoassay results showed that the linear range of CA125 was from 0.1 U mL−1 to 200 U mL−1 with the limit of detection (LOD) of 0.01 U mL−1 at signal to noise of 3. Quality control serum samples measured by our proposed immunosensor showed acceptable agreement with traditional ELISA method with the relative error less than 8.05%. The immunosensor exhibited good electrochemical performance with high reproducibility, reliability, stability and accuracy. The proposed immunosensor could be used for the determination of CA125 and had the potential for point-of-care testing (POCT) of other tumor marker.

GDF15 predict platinum response during first-line chemotherapy and can act as a complementary diagnostic serum biomarker with CA125 in epithelial ovarian cancer

BackgroundGrowth differentiation factor 15 (GDF15) has attracted much interest as a novel biomarker for epithelial ovarian carcinoma (EOC). Research focus has been directed at GDF15 as a diagnostic detection, while the prognostic determination of GDF15 in EOC patients remains to be clearly elucidated. The present study aimed to investigate GDF15 level relative to clinicopathological characters, chemoresponse, and clinical outcome of EOC patients.MethodsSerum from 122 patients with primary diagnosed EOC were analyzed for GDF15 and serum cancer antigen 125 (CA125). All cases were treated with debulking surgery and first-line chemotherapy, and samples were obtained just before debulking surgical treatment and first-line chemotherapy. Subsequently, clinical characteristics, responses to chemotherapy and progression-free survival (PFS) were recorded.ResultsIncreasing levels of serum GDF15 was significantly associated with FIGO stage and lymphonodus metastasis. GDF15 and CA125 detection are complementary in the diagnosis of EOC and can be simultaneously profiled. The chemo-resistant EOC patients (median, 1225.0 pg/mL) showed significantly higher GDF15 than chemo-sensitive patients (median, 824.2 pg/mL; P = 0.013). Highly expressed GDF15 was an independent negative prognostic indicator in the PFS (P = 0.026) of the 122 EOC cases in the multivariate analysis. Additionally, patients with high level of serum CA125 significantly associated with suboptimal (P = 0.043) debulking surgery.ConclusionsOur results provide valuable evidence that GDF15 is related with first-line chemo-resistance, with highly expressed GDF15 being a strong and an independent indicator of shorter PFS in EOC patients.

Sensitive on-chip detection of cancer antigen 125 using a DNA aptamer/carbon nanotube network platform

Despite the major role of cancer antigen 125 (CA125) in cancer progression, its structural diversity makes antibody-based immunoassay of this protein difficult. Here we report the selection of an anti-CA125 ssDNA aptamer and its application to sensitive detection of CA125 when used together with a CA125-specific antibody immobilized on a three-dimensional network of carbon nanotubes (3DN-CNTs). With exceptional stability and easy modifications over antibodies, the selected ssDNA aptamer (rCAA-8) showed high binding affinity (166nM) for recombinant CA125, which enabled CA125-specific imaging in ovarian cancer cells (OVCAR-3). Furthermore, when compared to other fluorescent assays based on graphene oxide or flat surface and traditional enzyme-linked immunosorbent assay, a chip-based assay using a 3DN-CNT surface and anti-CA125 antibody-aptamer pair resulted in higher sensitivity and broader dynamic range as a function of CA125 concentration, due to high target specificity and high surface loading density. Our on-chip aptamer-based assay will facilitate sensitive and specific monitoring of CA125 in the biological and clinical fields.

Serum CA125, CA199 and CEA Combined Detection for Epithelial Ovarian Cancer Diagnosis: A Meta-analysis.

ObjectiveTo evaluate the diagnostic value of combination detection of serum cancer antigen 125 (CA125), carbohydrate antigen 19-9 (CA199) and carci noembryonic antigen(CEA) in patients with epithelial ovarian cancer by pooling the open published studies according to meta-analysis method.MethodsDiagnostic studies related to combination detection of serum CA125, CA199 and CEA in patients with epithelial ovarian cancer were electronic searched in the databases of PubMed, Cochrane, Google scholar, EMBASE, ISI Web of Knowledge and CNKI by two independent reviewers. The combined diagnostic sensitivity, specificity, positive likely hood ratio (+LR), negative likely hood ratio (-LR), diagnostic odds ratio (DOR), and area under the receiver operating characteristic curve (AUC) were pooled by Med DiSc1.4 software.ResultsTwelve prospective diagnostic publications were finally fulfilled the inclusion criteria and were included in this meta-analysis. The pooled diagnostic sensitivity specificity, positive likely hood ratio, negative likely hood ratio, diagnostic odds ratio, and AUC were 0.90 (95%CI: 0.80 to 0.92), 0.83 (95%CI: 0.80 to 0.86), 5.35(95%CI:3.90 to 7.33), 0.13 (95%CI: 0.10 to 0.16), 48.53 (95%CI: 29.91 to 78.72) and 0.92 (95%C: 0.89 to 0.94) respectively by fixed or random effect model. No publication bias was found according to the funnel plot and line regression test (t=-1.34, P=0.21).ConclusionCombination detection serum CA125, CA199 and CEA was a promising biomarker forepithelial ovarian cancer diagnosis with relative high sensitivity and specificity.

Respective and simultaneous detection tumor markers CA125 and STIP1 using aptamer-based fluorescent and RLS sensors

Here we reported a method for the early diagnosis of ovarian cancer that is respective and simultaneous detection of tumour marker cancer antigen 125 (CA125) and stress-induced phosphoprotein 1 (STIP1) using aptamer-based fluorescent and RLS sensors. The fluorescent sensor was fabricated by Carboxyfluorescein (FAM)-labelled CA125 aptamer and cyanine-5-modified STIP1 aptamer onto the surface of RGO, thereby quenching the fluorescence of fluorophores. When STIP1 was introduced, the fluorescence recovered. When CA125 was added, the specific binding of aptamer and CA125 triggered the release of the FAM-labeled CA125 aptamer under the effect of formaldehyde, and adsorbed on the surface of RGO which lead to fluorescence quenching of FAM. This fluorescence signals change could be used to detect CA125 and STIP1 with the lowest detectable concentration down to 0.05UmL−1 and 1ngmL−1 respectively. The RLS sensor was fabricated by methyl violet interact with dsDNA which is obtained by CA125 aptamer hybridized to STIP1 aptamer. The dependence of RLS intensity on targets amount was successfully utilized for simultaneous detection of CA125 and STIP1, which provide robust evidences for the presence of ovarian cancer in the early stage. This strategy is reliable, sensitive, and may form the basis for rapid screening of ovarian cancer.

Smartphone-based immunosensor for CA125 detection

In this work, we report the design, the development and the characterization of the analytical performances of a colorimetric smartphone-based immunosensor for the detection of cancer antigen 125 (CA125). The immunosensor was based on a sandwich strategy in which the primary antibody was immobilized by spotting onto the 3D nitrocellulose membrane. The immunospots were subsequently incubated with CA125 solutions, followed by the affinity reaction with a secondary antibody labeled with gold nanoparticles (AuNPs). The antibody-AuNPs captured onto immunospots induced the silver deposition from a silver enhancer solution leading to the formation of gold-silver nanoparticles of different grey color spots depending on CA125 concentration. The 8 megapixels smartphone camera was integrated in a home-made dark box and used as transducer of color image acquisition and data handling. The pixel intensity of the captured images was determined by an image processing algorithm. The experimental parameters involved in each step of the immunosensor design were studied and optimized, obtaining a limit of detection of 30U/mL CA125. The selectivity of the immunoassay was proven against different concentration solutions of Vascular Endothelial Growth Factor (VEGF) antigen as an unspecific protein when a blank signal was obtained for all tested solutions. Finally, preliminary experiments in human serum samples spiked with CA125 protein were also performed. Therefore, the proposed system could represent a powerful point-of-care tool for the next generation technology for detecting and monitoring cancer biomarkers at early stages by taking advantage of nowadays gadgets with enhanced features such as smartphones.

Abstract 1373: IHC and RT-PCR assays for detection of cancer antigen NY-ESO-1 in human tissues

Abstract Introduction: NY-ESO-1 is a cancer testis antigen frequently expressed in a broad range of tumors: lung, breast, ovarian, bladder, liver cancer, melanoma, sarcoma and myeloma. CDX-1401, a fully human monoclonal antibody linked to full length NY-ESO-1, binds to dendritic cell (DC) receptor DEC-205 to stimulate NY-ESO-1 specific CD4 and CD8 responses. Immunohistochemistry (IHC) and quantitative RT-PCR (qRT-PCR) assays were developed to determine NY-ESO-1 expression in human tumors and normal adjacent tissues (NAT). A qRT-PCR assay for the detection of LAGE-1, a cancer testis antigen with significant DNA homology to NY-ESO-1, was also developed but no commercially specific antibody was available for IHC. Methods: Formalin fixed, paraffin embedded tumors and NAT were procured from a commercial source or obtained from Mosaic Laboratories; split anonymized samples were analyzed for NY-ESO-1 by IHC at Mosaic and for NY-ESO-1 and LAGE-1 by qRT-PCR at MolecularMD (OR) under IRB-approved protocols allowing in vitro analysis of remnant human samples. The study included: 18 each melanoma and ovarian cancers; 13 each colorectal (CRC), head &amp; neck (H&amp;N), and non-small cell lung cancers (NSCLC); and 38 NAT. HT1080 fibrosarcoma and SKOV3 ovarian cancer cell lines (ATCC, VA) and normal testis were used as controls. The qRT-PCR assays were validated using in vitro transcribed RNA on NY-ESO-1 and LAGE-1 kits provided by Life Technologies and the NY-ESO-1 IHC was developed using a mouse monoclonal antibody (Sigma, MO). Results: The NY-ESO-1 and LAGE-1 qRT-PCR assays had a linear range of 100-1,000,000 copies/reaction with limit of detection between 1-10 copies. An excess of LAGE-1 copies did not impact the specificity of the NY-ESO-1 assay and vice-versa. NY-ESO-1 protein was detected by IHC and NY-ESO-1 transcripts and LAGE-1 transcripts were detected in 9 (12%), 12 (16%) and 16 (21.3%), respectively, of the 75 tumor tissues while only 2 of the 38 normal samples were positive for LAGE-1. When stromal staining was considered in addition to epithelial staining, 16 (21.3%) tumor samples were positive by IHC. NY-ESO-1 protein was more prevalent in NSCLC (38%), ovarian cancer (11%) and melanoma (11%) vs. other tumor types. Positive staining by IHC was achieved in tumor tissues shown positive for NY-ESO-1 and negative for LAGE-1 transcripts. In general, tumor tissues obtained from Mosaic were of better quality, as assessed by the pathologist, and more positive than commercially procured samples. Conclusions: Two qRT-PCR assays were developed to specifically quantify NY-ESO-1 or LAGE-1 mRNA without cross reaction. The antibody used in IHC assay seemed specific to NY-ESO-1. Inadequate sample quality impacted target prevalence. Implementing these assays in clinical trials may aid in prospectively identifying patients with NY-ESO-1 positive malignancies who could derive benefit from investigational NY-ESO-1 vaccines designed to induce anti-tumor immunity, such as CDX-1401. Citation Format: Abdel Halim, Rebecca G. Bagley, Lisa Dauffenbach, Eric P. Olsen, Tibor Keler. IHC and RT-PCR assays for detection of cancer antigen NY-ESO-1 in human tissues. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1373.

Total internal reflection plasmonic scattering-based fluorescence-free nanoimmunosensor probe for ultra-sensitive detection of cancer antigen 125

Highly sensitive detection of cancer antigen 125 (CA125) on nanoarray chips was carried out by means of total internal reflection (TIR) microscopy based on fluorescent labeling (i.e., TIR fluorescence microscopy; TIRFM) and fluorescent-free labeling (TIR scattering microscopy; TIRSM). TIR plasmonic scattering of nanoparticles (NPs) as a fluorescence-free immunosensor probe potentially superior to fluorescent probes was applied to quantify CA125 on a nanoarray chip. NP-labeled CA125 (NP-CA125) was immunoreacted on chips, and the TIR scattering illumination of NP-CA125 allowed quantitative TIRSM measurement of wavelength-dependent plasmonic scattering detection of CA125. In addition, Alexafluor 488–labeled CA125 was immunoreacted on the same chips for comparison of detection sensitivity. TIRSM showed less photobleaching and higher photostability and detection sensitivity than TIRFM, as well as a lower limit of detection (LOD), 0.0018U/mL. This LOD was ~144 times lower than that of previously reported detection methods. These results demonstrated that the wavelength-dependent TIR plasmon NPs can be used as an enhanced nanoimmunosensor probe, providing ultra-sensitive fluorescence-free biomolecule detection to enable earliest-stage disease diagnosis.

In vitro selection of RNA aptamers against CA125 tumor marker in ovarian cancer and its study by optical biosensing

Early identification of neoplastic diseases is essential to achieve timely therapeutic interventions and significantly reduce the mortality of patients. A well-known biomarker is the Cancer Antigen 125 (CA125) or 16 mucin (MUC 16), a glycoprotein of the human family of mucins, already used for the diagnostic and prognostic evaluation of ovarian cancer. Therefore, the detection of CA125 to now remains a promising tool in the early diagnosis of this tumor. In this paper, we describe the development of RNA aptamers that bind with high affinity the tumor antigen CA125. We performed eight cycles of selection against CA125 purified protein. The selected aptamers were cloned and sequenced and the binding properties of the most promising sequences were studied by Real Time PCR and Surface Plasmon Resonance (SPR) to evaluate their ability in targeting CA125 protein with perspective applications in aptamer-based bioassays.

Tumor markers in serum and ascites in the diagnosis of benign and malignant ascites.

To evaluate the values of 4 tumor markers in serum and ascites and their ascites/serum ratios in the identification and diagnosis of benign and malignant ascites. A total of 76 patients were selected as subjects and divided into malignant ascites group (45 cases) and benign ascites group (31 cases). Samples of ascites and serum of all hospitalized patients were collected before treatment. The levels of carcinoembryonic antigen (CEA), alpha fetoprotein (AFP), cancer antigen 125 (CA125) and carbohydrate antigen 19-9 (CA19-9) were detected by chemiluminescence (CLIA) . CEA, AFP and CA19-9 in both serum and ascites as well as CA125 in ascites were evidently higher in the malignant ascites group than in the benign ascites group (P<0.01). Malignant ascites was associated with elevated ascites/serum ratios for AFP and CA125 (P<0.01). The areas under receiver operating characteristic (AUROCs) of CEA and CA125 in ascites and the ratios of ascites/serum of AFP, CEA, CA125 and CA19-9 were all >0.7, suggesting certain values, while those of ascites CA19-9 and serum CEA were 0.697 and 0.629 respectively, indicating low accuracy in the identification and diagnosis of benign and malignant ascites. However, the AUROCs of the remaining indexes were <0.5, with no value for identification and diagnosis. Compared with single index, the sensitivity of combined detection increased significantly (P<0.05), in which the combined detection of CEA, CA19-9 and CA125 in ascites as well as the ratio of ascites/serum of CEA, CA19-9, CA125 and AFP had the highest sensitivity (98.4%) but with relevantly low specificity. Both sensitivity and specificity of combined detection should be comprehensively considered so as to choose the most appropriate index. Compared with single index, combined detection of tumor markers in serum and ascites can significantly improve the diagnostic sensitivity and specificity.

Anticancer effects ofCarica papayain experimental induced mammary tumors in rats

Objective: To evaluate the anticancer effect of Carica papaya in DMBA induced mammary tumors in rats. Methods: Wistar rats were divided in to five groups (n=6), Group-I (Normal control) administered vehicle olive oil, Group-II, Group-III ,Group-IV and V induced mammary tumors by administering single dose of DMBA (7,12 Dimethyl benz(A)anthracene) orally 65 mg/kg. Group-III was administered aqueous leaf extract of Carica papaya (ALQECP) in a dose of 200 mg/kg body wt for a period of 3 months, group-IV has given ALQECP 200 mg/kg body wt for a period of 21 days post 3 months of tumor induction, group-V rats were administered a small dose of Carica papaya extract intra tumor locally in the region of tumor. Results: Values of CA15-3 were increased in group-II rats (tumor control) significantly, whereas in group-III (prevention group) the levels of CA15-3 were found to be reduced substantially and the P value < 0.001. Similarly, CA-15-3 levels were reduced significantly in group-IV (treatment group)and P<0.005. The levels of LDH were seen to be increased in group-II, where as in group-III LDH levels were decreased and P<0.001.similarly group-IV LDH levels also reduced significantly but not to the level of group-III. Conclusion: Among the various markers for the detection of cancer antigen- 15(CA15-3) and lactate dehydrogenase (LDH) are important biochemical parameters that give a clear understanding of the progression and proliferation of cancer cells. In this study it was found that there is increase in the levels of markers such as CA15-3 and LDH and also the tumor volume in tumor control, these marker levels were decreased by the administration of aqueous leaf extract of Carica papaya in a dose of 200 mg/kg body wt. ALQECP not only prevented the progression of cancer growth but also has significant effect in reducing the both CA15-3 and LDH levels in treatment group.