CACYBP and renal cell carcinoma: Considering the important role of the Wnt/ß-catenin pathway in carcinogenesis and the close relationship between WNT/β-catenin signaling, CacyBP/SIP and proteasomal activity, it seemed worthwhile to undertake research aimed at comparing the WNT/β-catenin pathway, CacyBP/SIP and LMP7 immunoproteasome in human samples of different RCC histological types.