Role of CD2-associated protein and nephrin expression in multilocular cystic renal cell carcinoma

Abstract

To investigate the role of CD2-associated protein (CD2AP) and nephrin expression in the multilocular cystic renal cell carcinoma (MCRCC) METHODS: Seventy four specimens of renal lesions, including 29 cases of MCRCC, 32 case of clear cell renal cell carcinoma (CCRCC), and 13 cases of simple renal cyst (SRC), were collected during operation. Immunohistochemistry was used to detect the CD2AP expression. Five wax lumps from each of the 3 groups of specimen, totally 15, were randomly selected to undergo re-sectioning and immunohistochemistry so as to compare the levels of staining intensity and location of expression of CD2AP and nephrin in the same sections. The expression of CD2AP in the MCRCC specimens was stronger than that in the CCRCC that was in turn stronger than that than that in the simple renal cyst (SRC) specimens. The epithelium lining the cysts in MCRCC was strongly positive in CD2AP compared to other parts. CCRCC showed a weak expression of CD2AP, while CD2AP was negative in the SRC specimens. The staining intensity and location of expression were completely identical for nephrin and CD2AP among the three types of tissue specimens. The CD2AP expression is much stronger in MCRCC than in CCRCC and SRC. CD2AP may be used as a biomarker in differential diagnosis of MCRCC, CCRCC, and SRC. The identical expression of CD2AP and nephrin in MCRCC and their specific expression in podocytes are important hints for the mechanism of MCRCC.