Other studies showed that the over-expression of circHIPK3 induced efficiently interaction with miR-558 and then down-regulated the expression of HPSE and its downstream targeted MMP-9 and VEGF to attenuate the promoting effect of miR-558 on bladder cancer cell migration, invasion, and angiogenesis (Li et al., 2017). This evidence concerns the gene MMP9 and urinary bladder cancer.