To identify the miRNAs affecting SOX9 expression, we transfected urothelial carcinoma cell lines with various miRNA precursors (hsa-miR-138-5p, 675, 26a, 23b, 331-3p, 145, 27a, 345, 139, 197, and 367) that are important in different types of cancer and searched for miRNAs that significantly affected SOX9 mRNA expression. Here, SOX9 is linked to urothelial carcinoma.