In the KEGG pathway analysis, both tobacco-flavored and menthol-flavored e-liquid exposure was associated with genes that are related to bladder cancer: CXCL8, HBEGF, CDKN2A, FGFR3, THBS1, CDK4, MYC, TYMP, MMP9, and MMP1. The gene discussed is MMP1; the disease is urinary bladder carcinoma.