However, an inverse association was found between duration of smoking cessation and methylation levels of two CpGs in RUNX3 and MIR196A1 genes in the control group (Spearman’s correlation analysis; Fig. 4a), but not in NSCLC patients (Fig. 4b), suggesting that a decrease in methylation level by smoking cessation might not occur after cancer has formed. The gene discussed is RUNX3; the disease is cancer.