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 (β 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 samples—even those that were collected from control territories—showed increased genotoxicity (micronucleus, ‱) compared to PM10. The study findings suggest that UFPs deserve special attention as a biological agent, distinct from larger PMs.

Short/long-term cryopreservation prior to comet assay of whole-blood leukocytes and in vitro-cultured lung fibroblasts

Single-cell gel electrophoresis (comet assay) is a valuable test that can be used in ecotoxicological, epidemiological, and biomonitoring contexts. We assessed the effects of short- (without cryopreservation) and long-term (with cryopreservation) storage of DMEM-cultivated human peripheral blood leukocytes (HPBLs) and a human lung fibroblast cell line (FLECH-104) on comet assay results. Samples were stored for 6 or 24 h at room temperature (23°С) or 4 °C and frozen at -80 °C or -196 °C for 1, 2, or 4 weeks. Short-term storage led to significant increases in the comet tail intensity (TI) and Olive tail moment (OTM) in HPBL and FLECH-104 samples. Freezing FLECH-104 samples at -80°С and -196°С resulted in TI mean increases, with no differences in OTM. All frozen HPBL samples did not exhibit significant increases in TI or OTM, and instead exhibited a slight decrease in TI versus the control at both -80 °C and -196 °C. Increased frequency of highly damaged cells was observed in FLECH-104 and HPBL cultures during both short-term storage and after freezing, which may indicate a significant destructive effect. Therefore, freezing of cell cultures and whole blood according to our protocol is not recommended.

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.