RRBP1 methylation in RT4 (low-metastatic cancer cell line), T24 and J82 (advanced bladder cancer cell lines), and BFTC909 (advanced urothelial cancer cell line) were lower than that in the normal cell line (methylation intensity: 36.42 unit for SV-HUC-1 and 28.32, 12.78, 11.56, and 17.65 for RT4, T24, J82, and BFTC909, respectively) (Supplementary Figure S2). Here, RRBP1 is linked to cancer.