In conclusion, the abnormal miRNA biogenesis in bladder cancer development might be a key mechanism in the aberrance of miRNA expressions and functions in BCa, and the dysregulated miRNAs will target the downstream signalling pathways such as ZEB1/2 and Survivin; they will eventually have a profound impact on the development of bladder cancer [84, 107-109] (Figure 4). This evidence concerns the gene ZEB1 and urinary bladder cancer.