The heatmap of the Nrf2 pathway-related genes across 18 cancer types showed the significant overexpressions of some genes, including FOSL1 in COAD, ESCA, and READ, MAFG in CHOL, MAPK3 in BRCA, and RIT1 in CHOL (Log2foldchange > 1.5) and the significant downregulations of some genes, including FOS in BLCA, BRCA, HNSC, KIRC, KIRP, LIHC, LUAD, LUSC, THCA, and UCEC, MAF in UCEC, MAPK9 in GBM, PRRT2 in GBM, and JUN in BLCA, BRCA, KICH, THCA, and UCEC (Log2foldchange < −1.5). The gene discussed is MAPK9; the disease is bladder transitional cell carcinoma.