Integrating apaQTL and eQTL analysis identifies a potential causal variant associated with lung adenocarcinoma risk in the Chinese population

Alternative polyadenylation (APA) plays a crucial role in cancer biology. Here, we used data from the 3′aQTL-atlas, GTEx, and the China Nanjing Lung Cancer GWAS database to explore the association between apaQTL/eQTL-SNPs and the risk of lung adenocarcinoma (LUAD). The variant T allele of rs277646 in NIT2 is associated with an increased risk of LUAD (OR = 1.12, P = 0.015), lower PDUI values, and higher NIT2 expression. The 3′RACE experiment showed multiple poly (A) sites in NIT2 , with the rs277646-T allele causing preferential use of the proximal poly (A) site, resulting in a shorter 3′UTR transcript. This leads to the loss of the hsa-miR-650 binding site, thereby affecting LUAD malignant phenotypes by regulating the expression level of NIT2 . Our findings may provide new insights into understanding and exploring APA events in LUAD carcinogenesis.