STAT3 and nonpapillary renal cell carcinoma: Specifically, we experimentally determined whether Wnt/β-catenin and IL6-JAK-STAT3 signal pathways were activated in ccRCC by examining the expression of TTC13, β-catenin, JAK2, p-STAT3, STAT3 and p-JAK2 in ccRCC tumor tissues as well as the adjacent normal tissues.