Background
Ovarian cancer (OC) is a great public health issue, and the relationship between OC and air pollution (AP) continues to be uncertain. Consequently, we implemented a TSMR analysis to assess the correlation between AP and the risk of OC.
Methods
From the UKB, we selected five risk factors related to AP (PM2.5, PM2.5-10, PM10, NO2, and NOx). The SNPs of OC from individuals of European and East Asian descent via the OCAC. Our main analytical technique was the IVW method, utilizing for calculating OR and 95% Cl. We implemented the weighted median, MR-Egger, simple, and weighted models for quality control, using Cochran's Q test for heterogeneity and MR-Egger regression and the MR-PRESSO test for pleiotropy detection. A leave-one-out strategy and the scatter plots were conducted to do sensitivity analyses. BMI, alcohol, and smoking were considered as potential mediators/confounders in MVMRs.
Results
Through TSMR analysis, we discovered a causal link between genetically inferred NOx commencement and OC risk in the European population (OR: 2.64, 95%CI: 1.152–6.087, P = 0.021). Some SNPs associated with the initiation of NOx production are linked toendometrioid OC(EnOC)risk (OR: 7.39, 95%CI: 1.209–45.171, P = 0.03). No statistical association was found between AP and OC levels in European (PM2.5: p = 0.993; PM2.5-10: p = 0.833; PM10: p = 0.257; NO2: p = 0.215; NOx: p = 0.614) or East Asian populations (PM2.5: p = 0.468; PM2.5-10: p = 0.814; PM10:p = 0.652; NO2: p = 0.392; NOx: p = 0.910). Even after adjusting for smoking and drinking through MVMR, a direct positive link between nitrogen oxide and OC risk was observed, which did not persist when BMI was accounted for (OR [95%CI] = 1.29 [0.76–2.19], p = 0.351), suggesting BMI may mediate the effect of nitrogen oxide on OC risk.
Conclusion
The results demonstrate a cause-and-effect relationship between exposure to NOx and OC risk, specifically for EnOC, within the European population.