Identification of Longitudinal miRNA Expression Changes Associated with Smoking Cessation in the Extra-thoracic Airway

Abstract

Cigarette smoking leads to cause premature deaths and preventable pulmonary diseases such as lung cancer and chronic obstructive pulmonary disease. Tobacco exposure elicits "Field of injury" and evokes similar molecular response throughout the airway epithelium. Smoking cessation increases life expectancy by reducing the risk of premature deaths from smoking related diseases. In this study, samples from the nasal epithelium were collected from active smokers enrolled in smoking cessation program. Using HiSeq illumina platform 2000, longitudinal miRNA expression profiling was performed to measure the individual level temporal transcriptomics changes in nasal epithelium upon smoking cessation. We have identified differential expressed miRNAs (n=49 at ANOVAp-val<0.05) and investigated their kinetics in individuals who have recently quit smoking. We also determined that miRNAs revert back towards their normal expression levels within 8 weeks of tobacco abstinence, with majority up-regulated. This study has also identified the putative target mRNAs of miRNAs related to smoking cessation and elucidated the regulatory mechanism involve in airway epithelium recovery from smoke induced injury. Smoking associated miRNAs determined in this study can be used to discover non-invasive biomarkers to capture smoking cessation effects. Our findings set a platform to evaluate the exposure of other environmental inhaled insults.