MiR-34a was epigenetically downregulated in MIBC. miR-34a expression was evaluated by qPCR in MIBC A) cell lines and B) patient tissues, U6 served as an internal control. Methylation analysis of miR-34a promoter region: C) profiling of the unit-specific methylation of CpG sites in the miR-34a promoter region was presented as an epigram. White circle means missing data at a given CpG unit; D) qRT-PCR demonstrated miR-34a expression in four MIBC cell lines after treatment with 5-aza-dC compared to mock-treated cells; Average methylation level of miR-34a promoter region in MIBC E) cell lines and F) patient tissues. Results are presented as mean + SEM of 3 independent experiments. *p < 0.05.