Air pollution and breast cancer risk: a Mendelian randomization study

Previous research yields inconsistent findings on the association between air pollution and breast cancer risk, with no definitive causal relationship established. To address this, we conducted a two-sample Mendelian randomization study on data from the IEU open GWAS databases and the Breast Cancer Association Consortium to explore the potential link between air pollution (including PM_2.5, PM_2.5 absorbance, PM_2.5–10, PM₁₀, NO₂, and NO_x) and breast cancer risk. We found that PM₁₀ (odds ratio (OR) = 1.39, 95% CI: 1.07–1.80, <i>p</i> = 0.013) and NO_x (OR = 1.67, 95% CI: 1.16–2.41, <i>p</i> = 0.006) were significantly associated with elevated breast cancer risk. Furthermore, PM_2.5 (OR = 2.10, 95% CI: 1.09–4.03, <i>p</i> = 0.027) and NO_x (OR = 3.08, 95% CI: 1.24–7.64, <i>p</i> = 0.015) were significantly associated with an elevated risk of luminal B/HER2-negative-like cancer. Results were stable in sensitivity analyses. This suggested that controlling air pollution could potentially reduce breast cancer risk.

既往研究关于空气污染与乳腺癌风险的关联结论并不一致，尚未确立明确的因果关系。为解决这一研究局限，我们基于IEU开放全基因组关联研究（open GWAS）数据库与乳腺癌协会联盟（Breast Cancer Association Consortium）的数据，开展了两样本孟德尔随机化（two-sample Mendelian randomization）研究，以探讨空气污染（包括细颗粒物PM₂.₅、PM₂.₅吸光度、PM₂.₅–₁₀、可吸入颗粒物PM₁₀、二氧化氮NO₂以及氮氧化物NOₓ）与乳腺癌风险的潜在关联。本研究发现，PM₁₀（比值比（OR）=1.39，95%置信区间（CI）：1.07–1.80，p=0.013）与NOₓ（OR=1.67，95%CI：1.16–2.41，p=0.006）与乳腺癌风险升高存在显著关联。进一步分析显示，PM₂.₅（OR=2.10，95%CI：1.09–4.03，p=0.027）与NOₓ（OR=3.08，95%CI：1.24–7.64，p=0.015）与腔面B型/HER2阴性样乳腺癌的风险升高显著相关。敏感性分析结果显示上述结论具有稳定性。本研究提示，管控空气污染或可降低乳腺癌发病风险。