Sputum Microbiome Composition in Patients with Squamous Cell Lung Carcinoma.

BACKGROUND: Recent findings indicate that the host microbiome can have a significant impact on the development of lung cancer by inducing an inflammatory response, causing dysbiosis, and generating genome damage. The aim of this study was to search for bacterial communities specifically associated with squamous cell carcinoma (LUSC). METHODS: In this study, the taxonomic composition of the sputum microbiome of 40 men with untreated LUSC was compared with that of 40 healthy controls. Next-Generation sequencing of bacterial 16S rRNA genes was used to determine the taxonomic composition of the respiratory microbiome. RESULTS: There were no differences in alpha diversity between the LUSC and control groups. Meanwhile, differences in the structure of bacterial communities (ß diversity) among patients and controls differed significantly in sputum samples (pseudo-F = 1.53; p = 0.005). Genera of Streptococcus, Bacillus, Gemella, and Haemophilus were found to be significantly enriched in patients with LUSC compared to the control subjects, while 19 bacterial genera were significantly reduced, indicating a decrease in beta diversity in the microbiome of patients with LUSC. CONCLUSIONS: Among other candidates, Streptococcus (Streptococcus agalactiae) emerges as the most likely LUSC biomarker, but more research is needed to confirm this assumption.

Chemical Composition and Toxicity of PM10 and PM0.1 Samples near Open-Pit Mines and Coal Power Stations.

Particulate matter (PM) <10 µm in size represents an extremely heterogeneous and variable group of objects that can penetrate the human respiratory tract. The present study aimed to isolate samples of coarse and ultrafine PM at some distance from polluting industries (1−1.5 km from the border of open-cast mines). PM was collected from snow samples which allowed the accumulation of a relatively large amount of ultrafine particles (UFPs) (50−60 mg) from five objects: three open-cast mines, coal power plants, and control territories. The chemical composition of PM was examined using absorption spectroscopy, luminescence spectroscopy, high-performance liquid chromatography, X-ray diffraction (XRD), and X-ray fluorescence (XRF) analyses of solid particle material samples. Toxicity was assessed in human MRC-5 lung fibroblasts after 6 h of in vitro exposure to PM samples. The absorption spectra of all the samples contained a wide non-elementary absorption band with a maximum of 270 nm. This band is usually associated with the absorption of dissolved organic matter (DOM). The X-ray fluorescence spectra of all the studied samples showed intense lines of calcium and potassium and less intense lines of silicon, sulfur, chlorine, and titanium. The proliferation of MRC-5 cells that were exposed to PM0.1 samples was significantly (p < 0.01) lower than that of MRC-5 cells exposed to PM10 at the same concentration, except for PM samples obtained from the control point. PM0.1 samples­even those that were collected from control territories­showed increased genotoxicity (micronucleus, ‱) compared to PM10. The study findings suggest that UFPs deserve special attention as a biological agent, distinct from larger PMs.

Sputum Microbiota in Coal Workers Diagnosed with Pneumoconiosis as Revealed by 16S rRNA Gene Sequencing.

Coal worker's pneumoconiosis (CWP) is an occupationally induced progressive fibrotic lung disease. This irreversible but preventable disease currently affects millions across the world, mainly in countries with developed coal mining industries. Here, we report a pilot study that explores the sputum microbiome as a potential non-invasive bacterial biomarker of CWP status. Sputum samples were collected from 35 former and active coal miners diagnosed with CWP and 35 healthy controls. Sequencing of bacterial 16S rRNA genes was used to study the taxonomic composition of the respiratory microbiome. There was no difference in alpha diversity between CWP and controls. The structure of bacterial communities in sputum samples (ß diversity) differed significantly between cases and controls (pseudo-F = 3.61; p = 0.004). A significant increase in the abundance of Streptococcus (25.12 ± 11.37 vs. 16.85 ± 11.35%; p = 0.0003) was detected in samples from CWP subjects as compared to controls. The increased representation of Streptococcus in sputum from CWP patients was associated only with the presence of occupational pulmonary fibrosis, but did not depend on age, and did not differ between former and current miners. The study shows, for the first time, that the sputum microbiota of CWP subjects differs from that of controls. The results of our present exploratory study warrant further investigations on a larger cohort.

Associations of polymorphisms in the cytokine genes IL1ß (rs16944), IL6 (rs1800795), IL12b (rs3212227) and growth factor VEGFA (rs2010963) with anthracosilicosis in coal miners in Russia and related genotoxic effects.

Anthracosilicosis (AS), a prevalent form of pneumoconiosis among coal miners, results from the accumulation of carbon and silica in the lungs from inhaled coal dust. This study investigated genotoxic effects and certain cytokine genes polymorphic variants in Russian coal miners with АS. Peripheral leukocytes were sampled from 129 patients with AS confirmed by X-ray and tissue biopsy and from 164 asymptomatic coal miners. Four single-nucleotide polymorphisms were genotyped in the extracted DNA samples: IL1ß T-511C (rs16944), IL6 C-174G (rs1800795), IL12b A1188C (rs3212227) and VEGFA C634G (rs2010963). Genotoxic effects were assessed by the analysis of chromosome aberrations in cultured peripheral lymphocytes. The mean frequency of chromatid-type aberrations and chromosome-type aberrations, namely, chromatid-type breaks and dicentric chromosomes, was found to be higher in AS patients [3.70 (95% confidence interval {CI}, 3.29-4.10) and 0.28 (95% CI, 0.17-0.38)] compared to the control group [2.41 (95% CI, 2.00-2.82) and 0.09 (95% CI, 0.03-0.15)], respectively. IL1ß gene T/T genotype (rs16944) was associated with AS [17.83% in AS patients against 4.35% in healthy donors, odds ratio = 4.77 (1.88-12.15), P < 0.01]. A significant increase in the level of certain chromosome interchanges among AS donors is of interest because such effects are typical for radiation damage and caused by acute oxidative stress. IL1ß T allele probably may be considered as an AS susceptibility factor among coal miners.

Chromosome aberrations in peripheral blood lymphocytes of lung cancer patients exposed to radon and air pollution.

Lung cancer is one of the most common forms of cancer. The aim of this study was to validate chromosome aberrations in peripheral blood lymphocytes of lung cancer patients living in a region with high air pollution and increased background radon levels as a biomarker of cancer risk. A total of 417 lung cancer patients and 468 control participants were analysed using a chromosome aberration assay in peripheral blood lymphocytes. The results showed that chromatid-type aberrations (2.26±1.58 vs. 1.60±1.58) and chromosome-type aberrations (CSAs) (0.96±1.36 vs. 0.42±0.70) in lung cancer patients were increased significantly in comparison with the controls. The most significant two-fold increase was detected for CSAs (nonsmoking patients: 0.84±1.54 vs. 0.41±0.73%, smoking patients: 0.99±1.31 vs. 0.44±0.67%). The frequency of dicentric and ring chromosomes, double minutes and rogue cells was significantly higher (P=0.002, 0.00002, 0.01, 0.0007) in the lung cancer patients. As both analysed groups lived in the same environment, our results show that increased radon levels were not the only source for the detected genome damage. Using binomial logistic regression, the estimated odds ratios and 95% confidence intervals adjusted for the main confounders (smoking, occupational exposure, age) were 1.31 (1.20-1.40) for chromatid-type aberrations, 1.28 (1.17-1.33), and 1.68 (1.49-1.88) for CSAs. It may be suggested that lung cancer patients show a significant increase in genome damage that may be caused by an interplay between exposure and individual low capacity of DNA repair, leading to genome instability.

Assessment of DNA damage in underground coal miners using the cytokinesis-block micronucleus assay in peripheral blood lymphocytes.

Coal miners are exposed to coal dust, containing mineral particles, inorganic compounds and polycyclic aromatic hydrocarbons, and to ionizing radiation. These factors can induce oxidative stress and promote inflammation that leads to DNA damage. The aim of this investigation is to analyse the degree of DNA damage in miners working in underground coal mines in Kemerovo Region (Russian Federation) using the cytokinesis-block micronucleus assay (CBMN) in peripheral blood lymphocytes. The exposed group included 143 coal miners (mean age = 50.11±7.36 years; mean length of service in coal mining conditions = 23.26±9.66 years). As a control group, we have used venous blood extracted from 127 healthy non-exposed men. The mean age in this group was 47.67±8.45 years. We have discovered that coal miners are characterized by a significant increase in the frequency of binucleated lymphocytes with micronuclei (MN), nucleoplasmic bridges (NPBs) and protrusions (NBUDs) compared to non-exposed donors. In addition, we report, for the first time, a reduction of cell proliferation in a cohort of coal miners. These data are evidence of the genotoxic and cytostatic effects of occupational harmful factors of the coal mining industry. No correlation between the level of chromosome damage and age, smoking status or length of service in coal mining conditions were discovered. We suggest that the CBMN assay would be useful in biomonitoring studies to monitor hygiene and prevention strategies in occupational settings in coal mining countries.

DNA excision repair and double-strand break repair gene polymorphisms and the level of chromosome aberration in children with long-term exposure to radon.

PURPOSE: To study polymorphic variants of repair genes in people affected by long-term exposure to radon. The chromosome aberration frequency in peripheral blood lymphocytes was used as the biological marker of genotoxicity. MATERIALS AND METHODS: Genotyping of 12 single nucleotide polymorphisms in DNA repair genes (APE, XRCC1, OGG1, ADPRT, XpC, XpD, XpG, Lig4 and NBS1) was performed in children with long-term resident exposure to radon. Quantification of the aberrations was performed using light microscopy. RESULTS: The total frequency of aberrations was increased in carriers of the G/G genotype for the XpD gene (rs13181) polymorphism in recessive model confirmed by the results of ROC-analysis ('satisfactory predictor', AUC = 0.609). Single chromosome fragments frequency was increased in carriers of the G/G genotype in comparison with the T/T genotype. In respect to the total frequency of aberrations, the G/G genotype for the XpG gene (rs17655) polymorphism was also identified as a 'satisfactory predictor' (AUC = 0.605). Carriers of the T/C genotype for the ADPRT gene (rs1136410) polymorphism were characterized by an increased level of single fragments relative to the T/T genotype. CONCLUSION: The relationships with several types of cytogenetic damage suggest these three SNP (rs13181, rs17655 and rs1136410) may be considered radiosensitivity markers.

Lymphocytes with multiple chromosomal damages in a large cohort of West Siberia residents: Results of long-term monitoring.

Cells with specific multiple chromosome aberrations, defined as rogue cells (RC) have been described in different populations, predominantly those exposed to radiation. The frequency, etiology and related health risks have still not been elucidated due to their low frequency of occurrences and rarely performed studies. This study reports RC frequency using chromosome aberration (CA) assay in peripheral lymphocytes in the group of 3242 subjects, during a 30-year long follow-up study in a general rural and urban population, children environmentally exposed to radon, occupationally exposed population and lung cancer patients from the Kemerovo region (Siberia, Russian Federation). Results show that the highest RC frequency was present in children environmentally exposed to radon and the lowest in the general urban population. Total frequency of CA did not correlate with frequency of RC. Genotoxic analysis of air and water samples excluded anthropogenic pollution as a possible cause of genome damage and RC frequency. In 85% of RCs, double minutes, observed in a large number of human tumors, were present. Results of CA analysis suggested that radon and its decay products (alpha-emitters) were the leading factors causing RC in subjects exposed to high LET radiation. Thus, RC may be a candidate biomarker for exposure to this type of radiation.

Modifying influence of occupational inflammatory diseases on the level of chromosome aberrations in coal miners.

Coal miners are exposed to a wide range of genotoxic agents that can induce genome damage. In addition, miners are characterised by a high risk of the initiation of different occupational inflammatory as well as non-inflammatory diseases. The aim of this investigation is to analyse the modifying influence of occupational pulmonary inflammatory diseases on the level of chromosome aberrations (CAs) in miners working in underground coal mines in Kemerovo Region (Russian Federation). The study group included 90 coal miners with the following pulmonary diseases: chronic dust-induced bronchitis (CDB) and coal-workers' pneumoconiosis (CWP) (mean age = 53.52±2.95 years; mean work experience in coal-mining conditions = 27.70±3.61 years). As a population control (control 1), we have used venous blood extracted from 124 healthy unexposed men. The mean age in this group was 50.92±4.56 years. Control 2 was the venous blood extracted from 42 healthy coal miners (mean age = 51.56±6.38 years; mean work experience in coal-mining conditions = 25.43±8.14 years). We have discovered that coal miners are characterised by an increased general level of CAs as well as an increased frequency of several types of CAs. The significant increase in the frequency of aberration per 100 cells and aberration of chromosome type was discovered in the group of pulmonary disease patients (study group). No correlations of the level of chromosome damage with age, smoking status and work experience in coal-mining conditions were discovered.

Assessing the level of chromosome aberrations in peripheral blood lymphocytes in long-term resident children under conditions of high exposure to radon and its decay products.

In this study, the frequency and spectrum of chromosomal aberrations were analysed in samples of peripheral blood from 372 (mean age = 12.24 ± 2.60 years old) long-term resident children in a boarding school (Tashtagol city, Kemerovo Region, Russian Federation) under conditions of high exposure to radon and its decay products. As a control group, we used blood samples from people living in Zarubino village (Kemerovo Region, Russian Federation). We discovered that the average frequencies of single and double fragments, chromosomal exchanges, total number of aberrations, chromatid type, chromosome type and all types of aberrations were significantly increased in the exposed group. This is evidence of considerable genotoxicity to children living under conditions of high exposure to radon compared to children living under ecological conditions without increased radon radiation.