Large-Scale Plasma Proteome Epitome Profiling is an Efficient Tool for the Discovery of Cancer Biomarkers.

Current proteomic technologies focus on the quantification of protein levels, while little effort is dedicated to the development of system approaches to simultaneously monitor proteome variability and abundance. Protein variants may display different immunogenic epitopes detectable by monoclonal antibodies. Epitope variability results from alternative splicing, posttranslational modifications, processing, degradation, and complex formation and possesses dynamically changing availability of interacting surface structures that frequently serve as reachable epitopes and often carry different functions.

Is Response to Genotoxic Stress Similar in Populations of African and European Ancestry? A Study of Dose-Response After Irradiation.

Exposure to genotoxic stress such as radiation is an important public health issue affecting a large population. The necessity of analyzing cytogenetic effects of such exposure is related to the need to estimate the associated risk. Cytogenetic biological dosimetry is based on the relationship between the absorbed dose and the frequency of scored chromosomal aberrations.

Telomere aberrations, including telomere loss, doublets, and extreme shortening, are increased in patients with infertility.

Objective: To test the hypothesis that telomere shortening and/or loss are risk factors for infertility.

Design: Retrospective analysis of the telomere status in patients with infertility using conventional cytogenetic data collected prospectively.

Setting: Academic centers.

Telomere and Centromere Staining Followed by M-FISH Improves Diagnosis of Chromosomal Instability and Its Clinical Utility.

Dicentric chromosomes are a relevant marker of chromosomal instability. Their appearance is associated with telomere dysfunction, leading to cancer progression and a poor clinical outcome. Here, we present Telomere and Centromere staining followed by M-FISH (TC+M-FISH) for improved detection of telomere dysfunction and the identification of dicentric chromosomes in cancer patients and various genetic syndromes.

A new tool for genotoxic risk assessment: Reevaluation of the cytokinesis-block micronucleus assay using semi-automated scoring following telomere and centromere staining.

Background: The cytokinesis-block micronucleus (CBMN) assay is an internationally recognized method for measuring DNA damage after exposure to genotoxic agents, as well as a biomarker for DNA repair and chromosomal instability. The high baseline level of micronuclei (MN) in the healthy population has limited the sensitivity and application of the CBMN assay for the follow-up of exposed populations. We reevaluated the sensitivity of the CBNM assay using semi-automated MN scoring following telomere and centromere (TC) staining after in vitro exposure to genotoxic agents (mitomycin or radiation) or aneugenic agents (vinblastine).

Benefit of an association of an antioxidative substrate and a traditional chinese medicine on telomere elongation.

Telomere shortening is involved in age-related disorders, such as cancer and cardiovascular diseases. Recently, telomerase re-activation strategies have been proposed to counteract telomere shortening and its consequences. Here, we investigated the benefit of dietary supplementation with a mix of S-adenosyl-methionine (SAMe) and a polysaccharide extract of Astragalus (APS) on telomere length of circulating lymphocytes of healthy volunteers.

Biological Dosimetry Network in Africa: Establishment of a Dose-Response Curve Using Telomere and Centromere Staining.

Purpose: Biological dosimetry, based on the relationship between the absorbed dose after exposure to ionizing radiation and the frequency of scored aberrations, has been and continues to be an important tool for estimating the dose after exposure. Dicentric chromosomes are considered to be the most specific and sensitive aberration related to radiation exposure. Here, we established the dose-response curve following in vitro irradiation of circulating lymphocytes from healthy donors from three African countries after scoring unstable chromosomal aberrations.

Erratum: Cuceu, C., et al. Independent Mechanisms Lead to Genomic Instability in Hodgkin Lymphoma: Microsatellite or Chromosomal Instability. 2018, , 233.

The authors wish to make the following corrections to this paper [...

Establishment and Characterization of a Reliable Xenograft Model of Hodgkin Lymphoma Suitable for the Study of Tumor Origin and the Design of New Therapies.

To identify the cells responsible for the initiation and maintenance of Hodgkin lymphoma (HL) cells, we have characterized a subpopulation of HL cells grown in vitro and in vivo with the aim of establishing a reliable and robust animal model for HL. To validate our model, we challenged the tumor cells in vivo by injecting the alkylating histone-deacetylase inhibitor, EDO-S101, a salvage regimen for HL patients, into xenografted mice. Blood lymphocytes from 50 HL patients and seven HL cell lines were used.

Independent Mechanisms Lead to Genomic Instability in Hodgkin Lymphoma: Microsatellite or Chromosomal Instability .

: Microsatellite and chromosomal instability have been investigated in Hodgkin lymphoma (HL). : We studied seven HL cell lines (five Nodular Sclerosis (NS) and two Mixed Cellularity (MC)) and patient peripheral blood lymphocytes (100 NS-HL and 23 MC-HL). Microsatellite instability (MSI) was assessed by PCR.

The Transition between Telomerase and ALT Mechanisms in Hodgkin Lymphoma and Its Predictive Value in Clinical Outcomes.

: We analyzed telomere maintenance mechanisms (TMMs) in lymph node samples from HL patients treated with standard therapy. The TMMs correlated with clinical outcomes of patients. : Lymph node biopsies obtained from 38 HL patients and 24 patients with lymphadenitis were included in this study.

Chromosomal Instability in Hodgkin Lymphoma: An In-Depth Review and Perspectives.

The study of Hodgkin lymphoma (HL), with its unique microenvironment and long-term follow-up, has provided exceptional insights into several areas of tumor biology. Findings in HL have not only improved our understanding of human carcinogenesis, but have also pioneered its translation into the clinics. HL is a successful paradigm of modern treatment strategies.

Transmission of Induced Chromosomal Aberrations through Successive Mitotic Divisions in Human Lymphocytes after In Vitro and In Vivo Radiation.

The mechanisms behind the transmission of chromosomal aberrations (CA) remain unclear, despite a large body of work and major technological advances in chromosome identification. We reevaluated the transmission of CA to second- and third-division cells by telomere and centromere (TC) staining followed by M-FISH. We scored CA in lymphocytes of healthy donors after in vitro irradiation and those of cancer patients treated by radiation therapy more than 12 years before.

Replication Timing of Human Telomeres is Conserved during Immortalization and Influenced by Respective Subtelomeres.

Telomeres are specific structures that protect chromosome ends and act as a biological clock, preventing normal cells from replicating indefinitely. Mammalian telomeres are replicated throughout S-phase in a predetermined order. However, the mechanism of this regulation is still unknown.

Comparison of Individual Radiosensitivity to γ-Rays and Carbon Ions.

Carbon ions are an up-and-coming ion species, currently being used in charged particle radiotherapy. As it is well established that there are considerable interindividual differences in radiosensitivity in the general population that can significantly influence clinical outcomes of radiotherapy, we evaluate the degree of these differences in the context of carbon ion therapy compared with conventional radiotherapy. In this study, we evaluate individual radiosensitivity following exposure to carbon-13 ions or γ-rays in peripheral blood lymphocytes of healthy individuals based on the frequency of ionizing radiation (IR)-induced DNA double strand breaks (DSBs) that was either misrepaired or left unrepaired to form chromosomal aberrations (CAs) (simply referred to here as DSBs for brevity).

Global quantification of γH2AX as a triage tool for the rapid estimation of received dose in the event of accidental radiation exposure.

The phosphorylation of the H2AX histone to form γH2AX foci has been shown to be an accurate biomarker of ionizing radiation exposure. It is well established that there is a one-to-one correlation between the number of γH2AX foci and radiation-induced double strand breaks in cellular DNA, which can be translated to the received dose. However, manual counting of foci is time-consuming, and cannot accommodate high throughput analysis required to obtain rapid results for medical triage purposes in the case of large-scale accidental exposure.

New tool for biological dosimetry: reevaluation and automation of the gold standard method following telomere and centromere staining.

Purpose: The dicentric chromosome (dicentric) assay is the international gold-standard method for biological dosimetry and classification of genotoxic agents. The introduction of telomere and centromere (TC) staining offers the potential to render dicentric scoring more efficient and robust. In this study, we improved the detection of dicentrics and all unstable chromosomal aberrations (CA) leading to a significant reevaluation of the dose-effect curve and developed an automated approach following TC staining.

Detection and automated scoring of dicentric chromosomes in nonstimulated lymphocyte prematurely condensed chromosomes after telomere and centromere staining.

Purpose: To combine telomere and centromere (TC) staining of premature chromosome condensation (PCC) fusions to identify dicentrics, centric rings, and acentric chromosomes, making possible the realization of a dose-response curve and automation of the process.

Methods And Materials: Blood samples from healthy donors were exposed to (60)Co irradiation at varying doses up to 8 Gy, followed by a repair period of 8 hours. Premature chromosome condensation fusions were carried out, and TC staining using peptide nucleic acid probes was performed.

Crosstalk between telomere maintenance and radiation effects: A key player in the process of radiation-induced carcinogenesis.

It is well established that ionizing radiation induces chromosomal damage, both following direct radiation exposure and via non-targeted (bystander) effects, activating DNA damage repair pathways, of which the proteins are closely linked to telomeric proteins and telomere maintenance. Long-term propagation of this radiation-induced chromosomal damage during cell proliferation results in chromosomal instability. Many studies have shown the link between radiation exposure and radiation-induced changes in oxidative stress and DNA damage repair in both targeted and non-targeted cells.

Lead Exposure Induces Telomere Instability in Human Cells.

Lead (Pb) is an important environmental contaminant due to its widespread use over many centuries. While it affects primarily every organ system of the body, the most pernicious effects of Pb are on the central nervous system leading to cognitive and behavioral modification. Despite decades of research, the mechanisms responsible for Pb toxicity remain poorly understood.

Discovery of lung cancer biomarkers by profiling the plasma proteome with monoclonal antibody libraries.

A challenge in the treatment of lung cancer is the lack of early diagnostics. Here, we describe the application of monoclonal antibody proteomics for discovery of a panel of biomarkers for early detection (stage I) of non-small cell lung cancer (NSCLC). We produced large monoclonal antibody libraries directed against the natural form of protein antigens present in the plasma of NSCLC patients.

Lipid metabolite levels of prostaglandin D2 and eicosapentaenoic acid recovered from bronchoalveolar lavage fluid correlate with lung function of chronic obstructive pulmonary disease patients and controls.

One-step global profiling of analyte (mRNA, protein, metabolite) biomarkers may soon replace conventional blood and histological/biopsy diagnostics technologies. It is important to establish whether the numerous blood and other body fluid-derived potential novel diagnostics will be sufficiently efficacious and precise to replace, for example, imaging and functional diagnostic tests. Currently, imaging technologies and spirometry are indispensable for the diagnosis and management of chronic obstructive pulmonary disease (COPD).

Monoclonal antibody proteomics: discovery and prevalidation of chronic obstructive pulmonary disease biomarkers in a single step.

We define mAb proteomics as the global generation of disease specific antibodies that permit mass screening of biomarkers. An integrated, high-throughput, disease-specific mAb-based biomarker discovery platform has been developed. The approach readily provided new biomarker leads with the focus on large-scale discovery and production of mAb-based, disease-specific clinical assay candidates.

Restriction endonuclease accessibility as a determinant of altered chromatin structure.

Active genes in eukaryotic genomes are typically found in open, nuclease-sensitive regions of chromatin. This chapter presents an overview of the techniques used to assay restriction endonuclease cleavage of chromosomal DNA as an approach to assess general accessibility at a genomic region of interest. We describe protocols to (1) prepare nuclei templates, (2) treat chromosomal DNA with a restriction enzyme(s), and (3) visualize and quantify chromosomal cleavage(s), with an emphasis on ligation-mediated (LM) PCR techniques.

Assessing the role of the T cell receptor beta gene enhancer in regulating coding joint formation during V(D)J recombination.

To assess the role of the T cell receptor (TCR) beta gene enhancer (Ebeta) in regulating the processing of VDJ recombinase-generated coding ends, we assayed TCRbeta rearrangement of Ebeta-deleted (DeltaEbeta) thymocytes in which cell death is inhibited via expression of a Bcl-2 transgene. Compared with DeltaEbeta, DeltaEbeta Bcl-2 thymocytes show a small accumulation of TCRbeta standard recombination products, including coding ends, that involves the proximal Dbeta-Jbeta and Vbeta14 loci but not the distal 5' Vbeta genes. These effects are detectable in double negative pro-T cells, predominate in double positive pre-T cells, and correlate with regional changes in chromosomal structure during double negative-to-double positive differentiation.