However, a statistically significant association between protachykinin-1 (trait: prot-a-2920) and the risk of lung squamous cell carcinoma was established (OR, 1.298; 95% CI, 1.049–1.548; p = 0.040; SNPs = 18) (Supplementary Figure S2). Here, TAC1 is linked to squamous cell lung carcinoma.