Early Diagnosis Of Cancer Patients Research Articles

Biocompatible epoxysilane substituted polymer-based nano biosensing platform for label-free detection of cancer biomarker SP17 in patient serum samples

Herein, we report the results of the studies relating to developing a simple, sensitive, cost-effective, and disposable electrochemical-based label-free immunosensor for real-time detection of a new cancer biomarker, sperm protein-17 (SP17), in complex serum samples. An indium tin oxide (ITO) coated glass substrate modified with self-assembled monolayers (SAMs) of 3-glycidoxypropyltrimethoxysilane (GPTMS) was functionalized via covalent immobilization of monoclonal anti-SP17 antibodies using EDC(1-(3-(dimethylamine)-propyl)-3-ethylcarbodiimide hydrochloride) - NHS (N-hydroxy succinimide) chemistry. The developed immunosensor platform (BSA/anti-SP17/GPTMS@SAMs/ITO) was characterized via scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle (CA), Fourier transform infrared (FT-IR) spectroscopic, and electrochemical techniques such as cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) techniques. The fabricated BSA/anti-SP17/GPTMS@SAMs/ITO immunoelectrode platform was used to measure changes in the magnitude of the current of the electrodes through an electrochemical CV and DPV technique. A calibration curve between current and SP17 concentrations exhibited a broad linear detection range of (100–6000 & 50–5500 pg mL−1), with enhanced sensitivity (0.047 & 0.024 μA pg mL−1 cm−2), limit of detection (LOD) and limit of quantification (LOQ) of 47.57 & 142.9 pg mL−1 and 158.58 & 476.3 pg mL−1, by CV and DPV technique, respectively with a rapid response time of 15 min. It possessed exceptional repeatability, outstanding reproducibility, five-time reusability, and high stability. The biosensor's performance was evaluated in human serum samples, giving satisfactory findings obtained via the commercially available enzyme-linked immunosorbent assay (ELISA) technique, proving the clinical applicability for early diagnosis of cancer patients. Moreover, various in vitro studies in murine fibroblast cell line L929 have been performed to assess the cytotoxicity of GPTMS. The results demonstrated that GPTMS has excellent biocompatibility and can be used for biosensor fabrication.

Highly sensitive SERS detection of IL-6 in serum by Au@Fe3O4 nanoring-based sandwich immunoassay

Detection of tumor markers is a key to realize the early diagnosis of cancer patients and improve the survival rate of patients. However, there are still great challenges in developing a highly sensitive and selective method to detect the tumor marker interleukin-6 (IL-6) of primary liver cancer, because the concentration of IL-6 in biological samples is limited and various interfering substances exist. Herein, a magnetic SERS immunoassay based on Fe3O4 nanoring (R-Fe3O4) was developed. The method could realize quantitative detection in 0.1–1000 pg/mL according to the sandwich principle and the detection limit of IL-6 reached 0.028 pg/mL. The excellent detection capability was mainly attributed to the characteristics of R-Fe3O4. Strong magnetism of R-Fe3O4 can enrich target molecules at low concentration, and the ring structure can facilitate the deposition of precious metal particles due to the high specific surface area, so as to promote the generation of hot spots and form electromagnetic enhancement. The method exhibited high selectivity for the identification of IL-6 and showed favorable detection results for IL-6 in serum samples. The ultra-sensitivity and high selectivity of the magnetic SERS immunoassay based on R-Fe3O4 would exhibit great development prospects in medical detection.

DNA walking system integrated with enzymatic cleavage reaction for sensitive surface plasmon resonance detection of miRNA

Abnormal expression levels of miRNA are associated with various tumor diseases, for example, glioma tumors are characterized by the up-regulation of miRNA-182. Surface plasmon resonance (SPR) assay for miRNA-182 from glioma patients was performed via DNA walking amplification strategy. The duplex between aminated swing arm DNA (swDNA) and block DNA (blDNA), and aminated track DNA (trDNA) with a biotin tag were tethered on the poly(ethylene glycol) (PEG)-modified chips. Upon formation of miRNA/blDNA duplex, the SPR signal decreased with the walking process of swDNA, as the biotinylated fragment of trDNA (biotin-TTGGAGT) was detached from the sensor surface caused by the nicking endonuclease Nb.BbvCI. Such a repeated hybridization and cleavage cycle occurred continuously and the detachment of more biotinylated fragments of trDNA from the chips led to the attachment of fewer streptavidin (SA) molecules and then smaller SPR signals. MiRNA-182 with concentrations ranging from 5.0 fM to 1.0 pM could be readily determined and a detection limit of 0.62 fM was achieved. The proposed method was highly selective and possessed remarkable capability for evaluating the expression levels of miRNA-182 in serum samples from healthy donors and glioma patients. The sensing protocol holds great promise for early diagnosis of cancer patients.

Amperometric detection of tumor suppressor protein p53 via pencil graphite electrode for fast cancer diagnosis

Cancer occupies the second place in terms of worldwide mortality. Early and fast diagnosis of cancer helps clinicians to expand therapeutic approaches ultimately leading towards early diagnosis of cancer patients. In the present work, we delineated an amperometric immunosensor to diagnose cancer to detect p53, a biomarker for cancer. The immunosensor was fabricated by immobilizing anti-p53 antibodies onto the pencil graphite electrode (PGE). The immobilization of probe was studied by scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The immunosensor was optimized for pH, incubation temperature, antibody concentration, incubation time and antigen concentration. The developed immunosensor, showed a linear range between 10 pgmL−1 to 10 ngmL−1 with a detection limit (LOD) of 10 pgmL−1. p53 antigen was analyzed by measuring current under optimal conditions. The occurrence of p53 was determined in sera of prostate, breast, colon and lung cancer patients by the present immunosensor. The lower incubation time i.e., fast response and lower LOD demonstrated an improved p53 immunosensor for early diagnosis of cancer.

Classification of histopathological gastric images using a new method

The number of patients who die from stomach cancer is still very excessive. Early diagnosis of cancer patients is necessary to reduce the death rate. In this case, a molecular structure classification system can help carry out early diagnosis of cancer. The existing system has some problems. These problems are high cost, low accuracy rate and waste of time. To tackle this problem, this article presents a new method. This method consists of a new size reduction algorithm called as extending extract histogram of oriented gradients (EEHOG). A multimodality size reduction method is obtained by combining the new EEHOG method and other dimension reduction methods (ODRM). Other dimension reduction methods are multidimensional scaling (MDS), Sammon mapping, Isomap, local linear embedding (LLE), Laplacian eigenmaps, stochastic neighbor embedding (SNE) and t-distributed stochastic neighbor embedding (t-SNE). As well, extract histogram of oriented gradients (EHOG) features have been calculated in this article. Then, EEHOG + MDS, EEHOG + Sammon mapping, EEHOG + Isomap, EEHOG + LLE, EEHOG + Laplacian Eigenmaps, EEHOG + SNE and EEHOG + t-SNE methods have been used for the dimensional reduction of the EHOG features. Thus, the high dimension of these features has been reduced to lower dimensions with a multimodality size reduction method. These new nominal feature sizes have been given to multilayer perceptron neural networks (MLP) and random forest (RF) classifier entries for classification of the histopathological stomach images. The accuracy results established by using the EEHOG + ODRM size reduction method are higher than the accuracy results obtained by using only ODRM. The accuracy result obtained with the MLP classifier is found to be higher from the accuracy results obtained with the RF classifier, when the performance of the MLP classifier is compared with the performance of the RF classifier. The stomach cancer images used this article were obtained from Firat University Medical Faculty Pathology Department. It has been found that the highest accuracy results are obtained as 98.14% with EHOG_EEHOG + LLE_MLP method. The average of the accuracy results obtained with the MLP classifier has been found as 89.57%. However, the average of the accuracy results obtained with the RF classifier has been found as 84.49%. These results have been compared with previous studies. It has been proven that more high accuracy results than single solutions of the multimodality solutions are given.

Monitoring Therapy Efficiency in Cancer through Extracellular Vesicles.

Extracellular vesicles (EVs) are a heterogeneous group of membrane-enclosed vesicles made of a phospholipid bilayer and are secreted by all cell types. EVs are present in a variety of body fluids containing proteins, DNA, RNA species, and lipids, and play an important role in cell- to-cell communication and are worth being considered as biomarkers for both early diagnosis of cancer patients and real-time monitoring of treatment response. Recently, emerging evidence verified EVs to have crucial roles in cancer progression and metastasis and a great potential in therapeutic applications. In this review, we discuss the potential of EVs in monitoring the efficacy of cancer therapies.

The potential of exosomes derived from colorectal cancer as a biomarker

Colorectal cancer (CRC) is one of the most frequent causes of cancer death. The diagnosis and treatment for metastatic CRC and patients with drug resistance remains poor. Cancer cells characteristically produce and release exosomes, which act as a new signal pattern in the occurrence and development of tumors. Circulating exosomes constitute promising biomarkers for early diagnosis of cancer patients. However, the potential of exosomes for clinical biomarker is hampered by their variousness and multi-sources. To this aim, we set out to solve the problem of discrimination and classification of exosomes. The cell culture supernatants of CRC cells, renal cell carcinoma cells and breast cancer cells were used for isolating exosomes. Then characteristic exosomal tumor markers were explored by Roche Cobas E601 fully automated electrochemiluminescence immunoassay systems, western blot and flow cytometry analysis. The results showed that CK19 was commonly expressed in exosomes derived from colorectal cells, TAG72 was mainly expressed in exosomes of 5-FU-resistant CRC cells and CA125 in those of high metastatic CRC cells. In addition, tumor interstitial fluid derived exosomes and patients' plasma derived exosomes showed different levels of CK19, TAG72 and CA125. Collectively, these data indicated that exosomes derived CK19 is correlated with colorectal tissue. TAG72-rich exosomes indicate that CRC patients might be resistant to 5-Fluorouraci. CA125-rich exosomes might be as metastatic CRC markers. These provide a good prospect for cell exosomes as novel, non-invasive clinical tool for diagnosing CRC and predicting its progression.

High Uric Acid (UA) Negatively Affects Serum Tartrate-Resistant Acid Phosphatase 5b (TRACP 5b) Immunoassay.

BackgroundBone metastases often occur in the majority of patients with advanced cancer, such as prostate cancer, lung cancer and breast cancer. Serum tartrate-resistant acid phosphatase 5b (TRACP 5b), a novel bone resorption marker, has been used gradually in the clinics as a specific and sensitive marker of bone resorption for the early diagnosis of cancer patients with bone metastasis. Here, we reported that high concentrations of uric acid (UA) lead to decrease of TRACP 5b levels and determined whether TRACP 5b level was associated with UA in interference experiment.MethodsA total of 77 patients with high concentrations of UA and 77 healthy subjects were tested to evaluate the differences in their TRACP 5b levels. Serial dilutions of UA were respectively spiked with a known concentration of TRACP 5b standard sample, then Serum TRACP 5b was detected by using bone TRAP® Assay. A correction equation was set to eliminate UA-derived TRACP 5b false-decrease. The effect of this correction was evaluated in high-UA individuals.ResultsThe average TRACP level of the high-UA individuals (1.47± 0.62 U/L) was significantly lower than that of the healthy subjects (2.62 ± 0.63 U/L) (t-test, p<0.0001). The UA correction equation derived: ΔTRACP 5b = -1.9751lgΔUA + 3.7365 with an R2 = 0.98899. Application of the UA correction equation resulted in a statistically non-significant difference in TRACP 5b values between the healthy subjects and high-UA individuals (p = 0.24).ConclusionsHigh UA concentrations can falsely decrease TRACP 5b levels due to a method-related systematic error. To avoid misdiagnoses or inappropriate therapeutic decisions, increased attention should be paid to UA interference, when TRACP 5b is used for early diagnosis of cancer patients with bone metastasis, evaluation of the aggressiveness of osteosarcoma or prediction of survival in prostate cancer and breast cancer with bone metastases.

Highly sensitive determination of the methylated p16 gene in cancer patients by microchip electrophoresis

The p16 tumor suppressor gene is inactivated by promoter region hypermethylation in many types of tumor. Recent studies showed that aberrant methylation of the p16 gene is an early event in many tumors, especially in lung cancer, and may constitute a new biomarker for early detection and monitoring of prevention trials. We detected tumor-associated aberrant hypermethylation of the p16 gene in plasma and tissue DNA from 153 specimens using a modified semi-nested methylation-specific PCR (MSP) combining plastic microchip electrophoresis or slab gel electrophoresis, respectively. Specimens were from 79 lung cancer patients, 15 abdominal tumor patients, 30 positive controls and 30 negative controls. The results showed that the positive rate obtained by microchip electrophoresis was more than 26.6% higher and the same specificity was kept when compared with slab gel electrophoresis. The microchip electrophoresis can rapidly and accurately analyze the PCR products of methylated DNA and obviously improve the positive rate of diagnosis of cancer patients when compared with gel electrophoresis. This method with the high assay sensitivity might be used for detection of methylation of p16 gene and even to facilitate early diagnosis of cancer patients.