Circulating autoantibodies against tumor-associated autoantigens (TAA) may serve as valuable biomarkers for a wide range of diagnostic purposes. Modern immunology offers a large variety of methods ...for in-depth comparative analysis of the repertoires of circulating antibodies’ antigenic specificities in health and disease. Nevertheless, this research field so far has met somewhat limited clinical success, while numerous data on the repertoires of circulating autoantibodies’ specificities in cancer patients are poorly integrated into the contemporary picture of the immunological and molecular landscapes of human tumors. This review is an attempt to identify and systematize the key and essentially universal conceptual and methodological limitations of analyses of the repertoires of circulating antibodies’ antigenic specificities in cancer (expression bias, redundancy of TAA repertoires, identification of natural IgG, the absence of the pathogenetically relevant context in the experimental systems used to detect TAA), as well as to discuss potential and already known methodological improvements that may significantly increase the detectability of the pathogenetically relevant and diagnostically significant
bona fide
TAA.
The Autoantibodies targeting Tumor-Associated Antigens (TAA-AAbs) emerge as a result of a variety of tumor-related immunogenic stimuli and may be regarded as the eyewitnesses to the anti-tumor immune ...response. TAA-AAbs may be readily detected in peripheral blood to unveil the presence of a particular TAA-expressing tumor, and a fair number of TAAs eliciting the tumor-associated autoantibody response have been identified. The potential of TAA-AAbs as tumor biomarkers has been extensively studied in many human malignancies with a major influence on public health; however, tumors of the endocrine system, and, in particular, the well-differentiated follicular cell-derived thyroid neoplasms, remain understudied in this context. This review provides a detailed perspective on and legitimate rationales for the potential use of TAA-AAbs in thyroid neoplasia, with particular reference to the already established diagnostic implications of the TAA-AAbs in human cancer, to the windows for improvement and diagnostic niches in the current workup strategies in nodular thyroid disease and differentiated thyroid cancer that TAA-AAbs may successfully occupy, as well as to the proof-of-concept studies demonstrating the usefulness of TAA-AAbs in thyroid oncology, particularly for the pre-surgical discrimination between tumors of different malignant potential in the context of the indeterminate results of the fine-needle aspiration cytology.
CD133 is an extensively studied marker of the most malignant tumor cell population, designated as cancer stem cells (CSCs). However, the function of this glycoprotein and its involvement in cell ...regulatory cascades are still poorly understood. Here we show a positive correlation between the level of CD133 plasma membrane expression and the proliferative activity of cells of the Caco-2, HT-29, and HUH7 cancer cell lines. Despite a substantial difference in the proliferative activities of cell populations with different levels of CD133 expression, transcriptomic and proteomic profiling revealed only minor distinctions between them. Nonetheless, a further in silico assessment of the differentially expressed transcripts and proteins revealed 16 proteins that could be involved in the regulation of CD133 expression; these were assigned ranks reflecting the apparent extent of their involvement. Among them, the TRIM28 transcription factor had the highest rank. The prominent role of TRIM28 in CD133 expression modulation was confirmed experimentally in the Caco2 cell line clones: the knockout, though not the knockdown, of the TRIM28 gene downregulated CD133. These results for the first time highlight an important role of the TRIM28 transcription factor in the regulation of CD133-associated cancer cell heterogeneity.
This work was aimed at quantitative determination of the absorbed doses under X-ray irradiation of cryogenic deposited films, particularly related to the matrix isolation experiment. The relative ...absorbed doses in the layers of solid noble gases of different thickness irradiated with an X-ray tube (46.6 kVp) in the specified cryostat geometry were calculated by Monte-Carlo simulation using a Geant4 code. In order to calibrate the obtained values, the relative absorbed dose in the ferrosulfate dosimeter irradiated in the same geometry was calculated in the same way. The effect of additional Al filter (420 μm) on the photon spectrum and relative absorbed dose in noble gas layers and dosimetric system was simulated. The experimental verification was based on the monitoring of the radiation-induced decay rate of ethane molecules isolated in different solid noble gas matrices (Ar, Kr, and Xe, 1:1000) irradiated in the cryostat at 6 K. It was shown that the simulation reproduces well the experimentally observed effect of the filter on relative absorbed dose rate in both dosimetric system and the layers of different solid noble gases (80–180 μm). Absolute absorbed dose rates were determined as a function of deposited layer thickness in different noble gases. The comparison of the simulation results with a crude estimation based on a single effective energy value is discussed.
•The relative absorbed doses for X-ray irradiation of solid noble gases were determined by MC simulations.•The effect of Al filter was used for comparison between simulation and experiment.•Good correlation between simulation and matrix isolation experiment was observed.•The reliability of absorbed dose estimation using effective energy approach is discussed.
Nanoparticles (NPs) with a high atomic number (Z) are promising radiosensitizers for cancer therapy. However, the dependence of their efficacy on irradiation conditions is still unclear. In the ...present work, 11 different metal and metal oxide NPs (from Cu (ZCu = 29) to Bi2O3 (ZBi = 83)) were studied in terms of their ability to enhance the absorbed dose in combination with 237 X-ray spectra generated at a 30–300 kVp voltage using various filtration systems and anode materials. Among the studied high-Z NP materials, gold was the absolute leader by a dose enhancement factor (DEF; up to 2.51), while HfO2 and Ta2O5 were the most versatile because of the largest high-DEF region in coordinates U (voltage) and Eeff (effective energy). Several impacts of the X-ray spectral composition have been noted, as follows: (1) there are radiation sources that correspond to extremely low DEFs for all of the studied NPs, (2) NPs with a lower Z in some cases can equal or overcome by the DEF value the high-Z NPs, and (3) the change in the X-ray spectrum caused by a beam passing through the matter can significantly affect the DEF. All of these findings indicate the important role of carefully planning radiation exposure in the presence of high-Z NPs.
The development of the physicochemical basis for applications of nanoradiosensitizers for targeted treatment of tumors is one of the crucial issues of modern radiotherapy. Ceramic nanoparticles (NPs) ...composed of heavy metal oxides are considered as prospective sensitizers, particularly for X-ray treatment. This study reports a novel approach for experimental simulations of the radiosensitizing effect of NPs in biomimetic systems based on the quantification of radicals produced from organic components in concentrated aqueous organic solutions using the spin-trapping technique with electron paramagnetic resonance detection. This approach was first applied to X-ray irradiation (45 kVp) of aqueous methanol solutions systems containing different concentrations of hafnium oxide nanoparticles with an average diameter of ca. 84 nm (up to 1.8 wp). It was found that the amount of radicals produced from methanol at the same exposition time increased linearly with the increasing content of HfO2 NPs. The effect can be reasonably explained by the physical enhancement mechanism associated with efficient transfer of absorbed energy from the NPs to aqueous organic medium. The Monte Carlo simulations were applied to calculate the absorbed dose in the studied systems as a function of NP concentration. The experimental enhancement factor in the formation of radicals (0.71 wp–1) was found to be slightly lower than the calculated coefficient of the absorbed dose enhancement (0.80 wp–1), which can be explained by partial self-absorption of generated secondary electrons inside rather bulky HfO2 nanoparticles. The proposed model approach may provide a rational ground for comparative studies of different nanoradiosensitizers and the optimization of the NP size, photon energy, and other factors.
We report a method for edge enhancement in the images of transparent samples using analog image processing in coherent light. The experimental technique is based on adaptive spatial filtering with an ...acousto-optic tunable filter in a telecentric optical system. We demonstrate processing of microscopic images of unstained and stained histological sections of human thyroid tumor with improved contrast.
Introduction: The plants of genus Empetrum, which are used in the traditional medicine to cure seizures and neurodegenerative diseases, can be considered as potent antiepileptic drugs. This paper ...focuses on a comparative analysis of an anticonvulsive activity of lipophilic fractions from Empetrum nigrum L.
Materials and methods: The experiments were conducted using mature outbred CD-1 male mice. The lipophilic fractions from aerial parts of Empetrum nigrum L. were administered through a catheter into the stomach at a dose of 150 mg/kg for 5 days. The anticonvulsive effects were studied using the acute seizure tests: strychnine-, pentylenetetrazole – and maximal electroshock (MES) induced tests. Carbamazepine was used as a positive control drug at a dose of 100 mg/kg.
Results and discussion: The acetone-soluble fraction (ASF) of the chloroform extract from Empetrum nigrum L. showed a pronounced anticonvulsive effect on seizures induced by strychnine (1.5 mg/kg) and pentylenetetrazole (150 mg/kg). In comparison to the control group, the time from seizures to death increased by 1.5 for the strychnine-induced seizures, and 1.9 times in case of pentylenetetrazole model. The survival rate of the animals was 22.2% and 20%, correspondingly. The survival rate in the MES test was 77.8%. Overall, ASF demonstrates a remarkable anticonvulsive activity in all the tests, especially in the MES test.
Conclusion: Our study for the first time shows a potent antiepileptic effect of ASF from Empetrum nigrum L., containing triterpene compounds and chalcones. The future studies will be focused on investigating the exact mechanisms of anticonvulsive and neuroprotective effects of ASF.
Graphical abstract:
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Tumor-associated antigen (TAA)-specific autoantibodies have been widely implicated in cancer diagnosis. However, cancer cell lines that are typically exploited as candidate TAA sources in ...immunoproteomic studies may fail to accurately represent the autoantigen-ome of lower-grade neoplasms. Here, we established an integrated strategy for the identification of disease-relevant TAAs in thyroid neoplasia, which combined NRASQ61R oncogene expression in non-tumorous thyroid Nthy-ori 3–1 cells with a multi-dimensional proteomic technique DISER that consisted of profiling NRASQ61R-induced proteins using 2-dimensional difference gel electrophoresis (2D-DIGE) coupled with serological proteome analysis (SERPA) of the TAA repertoire of patients with thyroid encapsulated follicular-patterned/RAS-like phenotype (EFP/RLP) tumors. We identified several candidate cell-based (nicotinamide phosphoribosyltransferase NAMPT, glutamate dehydrogenase GLUD1, and glutathione S-transferase omega-1 GSTO1) and autoantibody (fumarate hydratase FH, calponin-3 CNN3, and pyruvate kinase PKM autoantibodies) biomarkers, including NRASQ61R-induced TAA phosphoglycerate kinase 1 PGK1. Meta-profiling of the reactivity of the identified autoantibodies across an independent SERPA series implicated the PKM autoantibody as a histological phenotype-independent biomarker of thyroid malignancy (11/38 (29%) patients with overtly malignant and uncertain malignant potential (UMP) tumors vs 0/22 (p = 0.0046) and 0/20 (p = 0.011) patients with non-invasive EFP/RLP tumors and healthy controls, respectively). PGK1 and CNN3 autoantibodies were identified as EFP/RLP-specific biomarkers, potentially suitable for further discriminating tumors with different malignant potential (PGK1: 7/22 (32%) patients with non-invasive EFP/RLP tumors vs 0/38 (p = 0.00044) and 0/20 (p = 0.0092) patients with other tumors and healthy controls, respectively; СNN3: 9/29 (31%) patients with malignant and borderline EFP/RLP tumors vs 0/31 (p = 0.00068) and 0/20 (p = 0.0067) patients with other tumors and healthy controls, respectively). The combined use of PKM, CNN3, and PGK1 autoantibodies allowed the reclassification of malignant/UMP tumor risk in 19/41 (46%) of EFP/RLP tumor patients. Taken together, we established an experimental pipeline DISER for the concurrent identification of cell-based and TAA biomarkers. The combination of DISER with in vitro oncogene expression allows further targeted identification of oncogene-induced TAAs. Using this integrated approach, we identified candidate autoantibody biomarkers that might be of value for differential diagnostic purposes in thyroid neoplasia.
•The DISER(2D-DIGE + SERPA) is an integrated proteomic pipeline for identification of cell-based and autoantibody biomarkers.•In vitro expression of a specific oncogene focuses DISER on identification of oncogene-induced tumor-associated antigens.•NRASQ61R expression in human thyroid Nthy-ori 3–1 cells results in upregulation of NAMPT, GLUD1, GSTO1, and PGK1 proteins.•FH, PKM, CNN3, and PGK1 proteins elicit frequent autoantibody responses in human thyroid tumors.•Autoantibodies against PKM, CNN3, and PGK1 may be potentially used for differential diagnostic purposes in thyroid neoplasia.
Context:
Current methods of preoperative diagnostics frequently fail to discriminate between benign and malignant thyroid neoplasms. In encapsulated follicular-patterned tumors (EnFPT), this ...discrimination is challenging even using histopathological analysis. Autoantibody response against tumor-associated antigens is a well-documented phenomenon with prominent diagnostic potential; however, autoantigenicity of thyroid tumors remains poorly explored.
Objectives:
Objectives were exploration of tumor-associated antigen repertoire of thyroid tumors and identification of candidate autoantibody biomarkers capable of discrimination between benign and malignant thyroid neoplasms.
Design, Setting, and Patients:
Proteins isolated from FTC-133 cells were subjected to two-dimensional Western blotting using pooled serum samples of patients originally diagnosed with either papillary thyroid carcinoma (PTC) or EnFPT represented by apparently benign follicular thyroid adenomas, as well as healthy individuals. Immunoreactive proteins were identified using liquid chromatography-tandem mass-spectrometry. Pathological reassessment of EnFPT was performed applying nonconservative criteria for capsular invasion and significance of focal PTC nuclear changes (PTC-NCs). Recombinant T-complex protein 1 subunitζ (TCP-1ζ) was used to examine an expanded serum sample set of patients with various thyroid neoplasms (n = 89) for TCP-1ζ autoantibodies. All patients were included in tertiary referral centers.
Results:
A protein demonstrating a distinct pattern of EnFPT-specific seroreactivity was identified as TCP-1ζ protein. A subsequent search for clinicopathological correlates of TCP-1ζ seroreactivity revealed nonclassical capsular invasion or focal PTC-NC in all TCP-1ζ antibody-positive cases. Further studies in an expanded sample set confirmed the specificity of TCP-1ζ autoantibodies to malignant EnFPT.
Conclusions:
We identified TCP-1ζ autoantibodies as a potential biomarker for presurgical discrimination between benign and malignant encapsulated follicular-patterned thyroid tumors. Our results suggest the use of nonconservative morphological criteria for diagnosis of malignant EnFPT in biomarker identification studies and provide a peculiar example of uncovering the diagnostic potential of a candidate biomarker using incorporation of pathological reassessment in the pipeline of immunoproteomic research.
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