Non-Coding RNAs in Pulmonary Diseases: Comparison of Different Airway-Derived Biosamples

Abstract

Due to their structural conservation and functional role in critical signalling pathways, non-coding RNA (ncRNA) is a promising biomarker and modulator of pathological conditions. Most research has focussed on the role of microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs). These molecules have been investigated both in a cellular and an extracellular context. Sources of ncRNAs may include organ-specific body fluids. Therefore, studies on ncRNAs in respiratory diseases include those on sputum, bronchoalveolar lavage fluid (BALF) and exhaled breath condensate (EBC). It is worth identifying the limitations of these biosamples in terms of ncRNA abundance, processing and diagnostic potential. This review describes the progress in the literature on the role of ncRNAs in the pathogenesis and progression of severe respiratory diseases, including cystic fibrosis, asthma and interstitial lung disease. We showed that there is a deficit of information on lncRNAs and circRNAs in selected diseases, despite attempts to functionally bind them to miRNAs. miRNAs remain the most well-studied, but only a few investigations have been conducted on the least invasive biosample material, i.e., EBC. To summarise the studies conducted to date, we also performed a preliminary in silico analysis of the reported miRNAs, demonstrating the complexity of their role and interactions in selected respiratory diseases.

Circular RNA MKLN1 promotes epithelial-mesenchymal transition in pulmonary fibrosis by regulating the miR-26a/b-5p/CDK8 axis in human alveolar epithelial cells and mice models

“…CircRNA has been a hot topic in RNA research in recent years and is a potential therapeutic target and diagnostic biomarker for certain diseases. In current studies, some circRNAs have been found to be associated with pulmonary fibrosis, but they are still in the preliminary stage of research, and their mechanisms have not been fully elucidated (Stachowiak et al 2023 ; Zhou et al 2022 ). In smoking-induced pulmonary fibrosis, circRNA_0026344 was shown to target exosomal miR-21 to activate SMAD7, which involves abnormal crosstalk between epithelial cells and fibroblasts (Bai et al 2021 ).…”

microRNAs in exhaled breath condensate for diagnosis of lung cancer in a resource-limited setting: a concise review

“…Currently, there is no standardised method to assess EBC dilution. Besides this, miRNA concentrations in EBC may be affected by several other confounding factors [85][86][87]. Due to these drawbacks, the methodologies and interpretation of EBC studies are still evolving.…”

Whole Blood Expression Levels of Long Noncoding RNAs: HOTAIRM1, GAS5, MZF1-AS1, and OIP5-AS1 as Biomarkers in Adolescents with Obesity-Related Asthma

“…Nevertheless, even though several authors have focused on accurately classifying and discriminating all the asthma endotypes and phenotypes, there is still a significant knowledge gap between those entities, and certainly, the discovery of new molecular biomarkers is needed [ 11 ]. In the search for new disease biomarkers, genomics and transcriptomics studies, in combination with the increased accessibility of new molecular biology technologies, have accelerated the study of noncoding RNAs (ncRNAs) [ 12 ]. ncRNAs can be classified based on their length in small and long noncoding RNAs [ 13 ].…”