Crosstalk of miRNAs with signaling networks in bladder cancer progression: Therapeutic, diagnostic and prognostic functions

Urological cancers are considered as life-threatening diseases around the world. Bladder cancer is one of the most malignant urological tumors with high mortality and morbidity. Bladder cancer is a heterogenous disease and genetic alterations have shown to be key players in regulating its progression. Although conventional therapies are somewhat beneficial in improving prognosis and survival, bladder cancer patients suffer from recurrence. MicroRNAs (miRNAs) are endogenous short RNA molecules that do not encode proteins and show dysregulated expression in human cancers. miRNAs are regulators of vital biological processes in cells such as proliferation, migration, differentiation and apoptosis. Dysregulation of miRNAs is observed in bladder cancer and they are used as biomarkers for diagnosis and prognosis of patients. LncRNAs and circRNAs are modulators of bladder cancer progression via miRNA expression regulation. Overexpression of onco-suppressor miRNAs impairs bladder cancer progression, while oncogenic miRNAs drive tumor progression. Glycolysis and EMT mechanisms are two important factors for proliferation and migration of bladder cancer that are modulated by miRNAs. Furthermore, miRNAs can affect STAT3 and Wnt/β-catenin as instances of molecular factors in regulating bladder tumor progression. Bladder tumor response to drug therapy and radiotherapy is regulated by miRNAs. Hence, aim of current review is to provide function of miRNAs in bladder cancer based on their crosstalk with other molecular pathways and interaction with biological processes.