Appraising the causal relevance of DNA methylation for risk of lung cancer - Université Paris Cité Access content directly
Journal Articles International Journal of Epidemiology Year : 2019

Appraising the causal relevance of DNA methylation for risk of lung cancer

Silvia Polidoro
Kjell Grankvist
  • Function : Author
George Davey Smith
  • Function : Author
  • PersonId : 899170


Background: DNA methylation changes in peripheral blood have recently been identified in relation to lung cancer risk. Some of these changes have been suggested to mediate part of the effect of smoking on lung cancer. However, limitations with conventional mediation analyses mean that the causal nature of these methylation changes has yet to be fully elucidated. Methods: We first performed a meta-analysis of four epigenome-wide association studies (EWAS) of lung cancer (918 cases, 918 controls). Next, we conducted a two-sample Mendelian randomization analysis, using genetic instruments for methylation at CpG sites identified in the EWAS meta-analysis, and 29 863 cases and 55 586 controls from the TRICL-ILCCO lung cancer consortium, to appraise the possible causal role of methylation at these sites on lung cancer. Results: Sixteen CpG sites were identified from the EWAS meta-analysis [false discovery rate (FDR) < 0.05], for 14 of which we could identify genetic instruments. Mendelian randomization provided little evidence that DNA methylation in peripheral blood at the 14 CpG sites plays a causal role in lung cancer development (FDR > 0.05), including for cg05575921-AHRR where methylation is strongly associated with both smoke exposure and lung cancer risk. Conclusions: The results contrast with previous observational and mediation analysis, which have made strong claims regarding the causal role of DNA methylation. Thus, previous suggestions of a mediating role of methylation at sites identified in peripheral blood, such as cg05575921-AHRR, could be unfounded. However, this study does not preclude the possibility that differential DNA methylation at other sites is causally involved in lung cancer development, especially within lung tissue.
Fichier principal
Vignette du fichier
dyz190.pdf (873.71 Ko) Télécharger le fichier
Origin : Publisher files allowed on an open archive
Licence : CC BY - Attribution

Dates and versions

hal-02872348 , version 1 (07-06-2023)



Thomas Battram, Rebecca Richmond, Laura Baglietto, Philip Haycock, Vittorio Perduca, et al.. Appraising the causal relevance of DNA methylation for risk of lung cancer. International Journal of Epidemiology, 2019, 48 (5), pp.1493-1504. ⟨10.1093/ije/dyz190⟩. ⟨hal-02872348⟩
42 View
13 Download



Gmail Facebook X LinkedIn More