Although many factors may be associated with the pathogenesis and mechanisms of above diseases, some cytokines, including tumor necrosis factor-α (TNF-α), interleukin-17 (IL-17) cytokine family and interferon (IFN) are considerably involved in the occurrence and development of cystitis, bladder polyp and bladder cancer [6, 7]. Here, IL17A is linked to cystitis.