microRNAs are key regulators in chronic lung disease: exploring the vital link between disease progression and lung cancer

microRNAs (miRNAs) bind to mRNAs and inhibit their expression through post-transcriptionally regulating gene expression. Here, we elaborate upon the concise summary of the role of miRNAs in carcinogenesis with specific attention to precursor respiratory pathogenesis caused by cigarette smoke modulation of these miRNAs. We review how miRNAs are implicated in cigarette-smoke-driven mechanisms, such as epithelial to mesenchymal transition, autophagy modulation, and lung ageing, which are important in the development of chronic obstructive pulmonary disease and potential progression to lung cancer. Extracellular vesicles are key to inter-cellular communication and sharing of miRNAs. A deeper understanding of the role of miRNAs in chronic respiratory disease and their use as clinical biomarkers has great potential. Therapeutic targeting of miRNAs may significantly benefit the prevention of cancer progression.