Down-regulation of circulating microRNA let-7a in Egyptian smokers

Abstract

Altered miRNAs were associated with cigarette smoking. The study aimed to examine the gene expression level of plasma let-7a among healthy smokers and compared it with the non-smokers. Forty subjects were recruited for the present study and classified into 21 smokers and 19 non-smokers, age, and sex were matched. The software that used to design functional primers was MIRprimer. Quantitative real-time PCR was employed to compare the relative expression of plasma let-7a. Results showed that the level of let-7a was down-regulated in smokers to 0.34fold (p = 0.006) that of the non-smokers. Plasma let-7a showed an area under curve (AUC) of 0.749 with sensitivity 43% and specificity 100%. In conclusion, plasma let-7a was significantly down-regulated in the smokers, and it might be considered a candidate biomarker to discriminate between smokers and non-smokers.

Keywords: Biomarker; Cigarette smoking; Plasma let7-a; Software MIRprimer.

Fig. 1

Relative plasma let-7a levels in smoker and non-smoker population. Expression levels of let-7a were normalized to Mir-16. Data was represent as median value and Mann-Whitney U test was used to define statistical significance.

Fig. 2

Receiver operating characteristics (ROC) curve analysis for investigated plasma let7a.