DIFFERENTIAL DNA METHYLATION
ACTIVATED RECEPTOR 4
Smoking accounts for a large share of lung cancer. F2RL3 methylation was recently identified as a biomarker closely reflecting both current and past smoking exposure. We aimed to assess the associations of F2RL3 methylation with lung cancer incidence and mortality. In a large population-based cohort study, F2RL3 methylation was measured in baseline blood samples of 4,987 participants by MassARRAY. Associations of F2RL3 methylation and smoking with lung cancer incidence/mortality during a median follow-up of 10.9 years were assessed by Cox regression, controlling for potential confounders. The ability of F2RL3 methylation to predict lung cancer was examined by Harrell's C statistics. Hypomethylation at F2RL3 was strongly associated with both lung cancer incidence and mortality, with age- and sex-adjusted hazard ratios (HR; 95% CI) of 9.99 (5.61-17.79) and 16.86 (8.53-33.34), respectively, for participants whose methylation intensity were 0.54 compared with whose methylation intensity were 0.75. Strongly elevated HRs of 2.88 (1.42-5.84) and 5.17 (2.28-11.70) persisted even after controlling for multiple covariates including smoking status and pack-years. With fully adjusted HRs of 9.92 (2.88-34.12) and 16.48 (4.10-66.15), the associations between methylation and the two outcomes were particularly strong among participants65 years. Combination of F2RL3 methylation and pack-years predicted lung cancer incidence with high accuracy (optimism-corrected Harrell's C statistics=0.86 for participants65 years). These findings suggested that F2RL3 methylation is a very strong predictor of lung cancer risk and mortality, particularly at older age. The potential implications of F2RL3 methylation for early detection, risk stratification and prevention of lung cancer warrant further exploration.
What's new? Methylation of F2RL3 is linked to both current and lifetime smoking exposure, making it a potentially valuable marker for the assessment of lung cancer risk. This population-based prospective cohort study strengthens that potential, showing that F2RL3 hypomethylation, as measured in blood samples, is strongly predictive of lung cancer incidence and mortality. The association was significant regardless of whether F2RL3 methylation was considered alone or in combination with smoking status or pack-years. It was particularly strong in individuals aged 65 or older.
Type of Publication:
Journal article published