We observed for the first time that DAC-induced DNA demethylation upregulated NOTCH1 mRNA in bladder cancer cells suggesting a functional role for DNA methylation in the transcriptional regulation of NOTCH1. We examined 4 and 7 CG dinucleotides in the promoter and enhancer regions, respectively, and detected significant DNA demethylation. Here, NOTCH1 is linked to urinary bladder cancer.