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Introduction: There is still a debate for the link between obstructive sleep apnoea (OSA) and cancer. The mechanisms underlying this causality are poorly understood. Several miRNAs are involved in cancer development and progression with expression being influenced by hypoxia. The aims of this work were (i) to compare miRNAs expression in controls versus patients affected by OSA without or with cancer (ONCO-OSA) and (ii) in colorectal cancer cells exposed to intermittent hypoxia (IH), to evaluate miRNAs impact on tumor progression in vitro., Methods: We detected miRNAs by qRT-PCR in patients' sera and in CaCo2 cells exposed to 2-32h of IH with or without acriflavine (ACF), a HIF-1 inhibitor. Viability and transwell invasion test were applied to investigate the proliferation and migration of CaCo2 exposed to IH and treated with miRNA inhibitors or acriflavine. HIF-1α activity was evaluated in CaCo2 cells after IH., Results: The levels of miR-21, miR-26a and miR-210 increased in OSA and ONCO-OSA patients compared to controls. MiR-23b increased in ONCO-OSA patients, and miR-27b and miR-145 increased in OSA but not ONCO-OSA patients. MiR-21, miR-26a, miR-23b and miR-210 increased in cells after IH. IH stimulated cell proliferation and migration. This effect was reduced after either miRNA inhibition or acriflavine treatment. MiRNA inhibition reduces HIF-1α gene expression. Conversely, acriflavine reduced the expression of these miRNAs., Conclusions: We identified a signature of miRNAs, induced by the IH environment. They could be implicated in cancer development and progression through a regulatory loop involving HIF-1., (Copyright © 2023 The Author(s). Published by Elsevier España, S.L.U. All rights reserved.)

Objective: Asthma inflammation may feature an imbalance between oxidative stress and antioxidant defenses. Oxidative stress induces propagation of airways inflammation and corticosteroid insensitivity contributing to poor asthma control, and frequent severe acute exacerbations. This study assessed inflammation and oxidative stress in severe asthmatic subjects and evaluated the possible correlations between inflammatory and oxidative stress markers investigated and asthma severity., Material and Method: Fifty-three patients with severe asthma, 11 patients with mild-moderate asthma and 12 healthy subjects were enrolled and underwent fractional exhaled nitric oxide (FENO) analysis and blood and sputum count cell collection. The content of mitochondrial DNA (MtDNA) and nuclear DNA (nDNA) was measured in exhaled breath condensate (EBC) by Real Time PCR and the ratio between MtDNA/nDNA was calculated. We detected MtDNA/nDNA in the EBC of severe asthmatics., Results: We found higher exhaled MtDNA/nDNA in severe asthmatics respectively compared to mild-moderate ones and to healthy controls (10.4±2.2 vs 7.9±2.5, p<0.05 and 10.4±2.2 vs 6.51±0.21, p<0.05). The level of exhaled MtDNA/nDNA was significantly higher in Non-T2 endotype severe asthmatics than T2 (14.07±10. 8 vs 6.5±5.5, p<0.05)., Conclusion: Oxidative stress marker (MtDNA/nDNA) is increased significantly with asthma severity and may be useful for endotyping severe asthma., (Copyright © 2020 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.)

Introduction: Several studies have previously demonstrated that long-term exposure to outdoor pollution present airway inflammation in term of an increase of sputum neutrophils., Aim and Methods: The aim of our study was to evaluate the level of airway inflammation by induced sputum in a group of 15 non-professionally exposed population of well-characterized COPD patients, residing in urban areas with high rate of outdoor pollution, compared to a control group of 13 individuals with COPD, living in rural areas with a low pollution rate. All participants underwent spirometry and sputum induction., Results: A statistically significant increase in the percentage of neutrophil cell count was found among the residents in urban areas compared to those living in rural regions (89.1 vs 79.0, p<0.05) CONCLUSIONS: In conclusion, we showed that non-professionally exposed patients with COPD residing in highly-polluted urban areas had greater airway inflammation in terms of sputum neutrophils compared to a population with very similar characteristics, living in rural areas with lower outdoor pollution. The results of this pilot study may be relevant for the long term effect of environmental outdoor pollution in vulnerable patients like those with COPD., (Copyright © 2019 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.)