Hypomethylation of smoking-related genes is associated with future lung cancer in four prospective cohorts

• Published in: Nature communications 2015-12, Vol.6 (1), p.10192-10192, Article 10192
• Main Authors: Fasanelli, Francesca, Baglietto, Laura, Ponzi, Erica, Guida, Florence, Campanella, Gianluca, Johansson, Mattias, Grankvist, Kjell, Johansson, Mikael, Assumma, Manuela Bianca, Naccarati, Alessio, Chadeau-Hyam, Marc, Ala, Ugo, Faltus, Christian, Kaaks, Rudolf, Risch, Angela, De Stavola, Bianca, Hodge, Allison, Giles, Graham G., Southey, Melissa C., Relton, Caroline L., Haycock, Philip C., Lund, Eiliv, Polidoro, Silvia, Sandanger, Torkjel M., Severi, Gianluca, Vineis, Paolo
• Format: Article
• Language: English
• Subjects: 631/208/176/1988; 692/699/67/1612; 692/699/67/2324; 692/699/67/68; Adult; Aged; Cancer; Cohort Studies; Community medicine, Social medicine: 801; CpG Islands; Deoxyribonucleic acid; Diagnostic systems; DNA; Female; Gene Expression Regulation - physiology; Genes; Genetic Predisposition to Disease; Health risk assessment; Health risks; Health sciences: 800; Helsefag: 800; Humanities and Social Sciences; Humans; Lung cancer; Lung Neoplasms - genetics; Male; Medical disciplines: 700; Medisinske Fag: 700; Methylation; Middle Aged; multidisciplinary; Odds Ratio; Risk; Samfunnsmedisin, sosialmedisin: 801; Science; Science (multidisciplinary); Smoking; Smoking - genetics; Tobacco; VDP
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms10192

DNA hypomethylation in certain genes is associated with tobacco exposure but it is unknown whether these methylation changes translate into increased lung cancer risk. In an epigenome-wide study of DNA from pre-diagnostic blood samples from 132 case–control pairs in the NOWAC cohort, we observe that the most significant associations with lung cancer risk are for cg05575921 in AHRR (OR for 1 s.d.=0.37, 95% CI: 0.31–0.54, P -value=3.3 × 10 −11 ) and cg03636183 in F2RL3 (OR for 1 s.d.=0.40, 95% CI: 0.31–0.56, P -value=3.9 × 10 −10 ), previously shown to be strongly hypomethylated in smokers. These associations remain significant after adjustment for smoking and are confirmed in additional 664 case–control pairs tightly matched for smoking from the MCCS, NSHDS and EPIC HD cohorts. The replication and mediation analyses suggest that residual confounding is unlikely to explain the observed associations and that hypomethylation of these CpG sites may mediate the effect of tobacco on lung cancer risk. Smoking tobacco is known to alter DNA methylation. Here, the authors show that hypomethylation of smoke-related genes is associated with future increase in lung cancer risk.