ObjectiveTo identify causal effects and potential mechanisms of oxidative stress (OS) genes in lung cancer. MethodsOS-related genes were extracted from the GeneCards database. Integration analysis of genome-wide association study (GWAS) data for lung cancer with gene expression and DNA methylation quantitative trait loci (eQTL and mQTL) in blood was performed using the summary data-based Mendelian randomization (SMR) approach to determine the causal relationship between OS genes and lung cancer risk. Colocalization analysis of OS gene QTLs and lung cancer risk loci was performed to gain insight into the potential regulatory mechanisms of lung cancer risk. ResultsA potential causal relationship between OS-related genes and lung cancer was identified by SMR analysis. AGER expression level was found to be associated with lung cancer risk [OR=1.944, 95%CI (1.431, 2.640), P<0.001], and ATF6B expression level was associated with lung cancer risk [OR=1.508, 95%CI (1.287, 1.767), P<0.001]. Meanwhile, ATF6B methylation level was associated with lung cancer risk. ConclusionOS-related genes are associated with lung cancer, which may be a potential site of action for anti-cancer drugs.
Objective To explore the causal relationship between the Collagen VI (COL6) family proteins COL6A1, A2, and A3 and bronchiectasis using the Mendelian randomization (MR) method.MethodsThe primary analysis was conducted using MR combined with summary-data-based Mendelian randomization (SMR) analysis. COL6 family proteins were used as exposure data, and bronchiectasis was used as outcome data. Cis-protein quantitative trait locus (cis-pQTL) data were extracted for analysis, and the results were meta-analyzed. Subsequently, COL6A3-cis-pQTL data from the UK Biobank plasma proteome study were used for further validation. Colocalization analysis was also performed to further explore the association between COL6 proteins and bronchiectasis.Results MR and SMR results revealed a negative causal relationship between COL6A3 and bronchiectasis (p-MRmeta = 0.005, OR = 0.30; p-SMRmeta = 0.004, OR = 0.26). The validation phase also confirmed the negative causal relationship between COL6A3 and bronchiectasis (p-MRmeta = 0.000007, OR = 0.27; p-SMRmeta = 0.0003, OR = 0.29). Colocalization analysis supported the presence of a shared causal variant (rs972974) between COL6A3 and bronchiectasis (PP.H4 = 0.967/0.876).Conclusion There is an inverse causal relationship between COL6A3 and bronchiectasis. Low expression of COL6A3 increases the risk of developing bronchiectasis, making COL6A3 a potential biomarker and therapeutic target for drug development in bronchiectasis.