PTPRZ1 and hereditary clear cell renal cell carcinoma: In renal cell carcinoma cell lines, β-catenin has been found to co-immunoprecipitate with PTPRZ1, and downregulation of PTPRZ1 by siRNA led to increased tyrosine phosphorylation of β-catenin and a significant decrease of nuclear β-catenin, leading to decreased cell proliferation [16].