Ambient air pollution and the risk of cancer: evidence from global cohort studies and epigenetic-related causal inference

Abstract

The correlation between air pollution and cancer incidence has been a longstanding concern, understanding the need to elucidate the specifics of this relationship. Thus, this study aimed to assess the association between exposure to air pollution and cancer incidence, and to identify the possible biological links between the two. We examined global cohort studies investigating the association between air pollution and cancer and performed a univariate Mendelian randomization (MR) analysis. Our analysis revealed that the presence of particulate matter (PM)_2.5, PM₁₀, NO₂, and NO_x substantially impacted the risk of developing cancer. MR analysis identified 130 CpGs sites associated with three ambient air pollutants that have significant casual effects on the risk of 14 cancer sites (false discovery rate<0.05). Gene annotation was conducted using g-Profiler by screening for single nucleotide polymorphisms significantly associated with outcome, followed by analysis of the gene interaction network using GeneMANIA, and visualization using igraph. In conclusion, this study demonstrates that air pollution has a significant impact on cancer incidence, provides strong evidence for an epigenetic causal link between the two, and provides new insights into the molecular mechanisms by which air pollution affects cancer development.