PIK3R1 and urinary bladder cancer: Four binding sites of hsa-miR-127-3p including SNP-56, −2236, −2611 and −3496 were identified in the 3′ untranslated region of PIK3R1 mRNA, suggesting that single SNPs located at miRNA-binding sites are likely to affect the expression of their targets and might contribute to the pathogenesis of bladder cancer.