Claudin-7 is Highly Expressed in Chromophobe Renal Cell Carcinoma and Renal Oncocytoma.
10.3346/jkms.2007.22.2.305
- Author:
Yoo Duk CHOI
1
;
Ki Seung KIM
;
Sunhyo RYU
;
Youngkyu PARK
;
Nam Hoon CHO
;
Seo Hee RHA
;
Ja June JANG
;
Jae Y RO
;
Sang Woo JUHNG
;
Chan CHOI
Author Information
1. Department of Pathology, Chonnam National University Medical School, 5 Hak-dong, Dong-gu, Gwangju, Korea. cchoi@chonnam.ac.kr
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
Chromophobe Renal Cell Carcinoma;
Oncocytoma;
Claudin-7
- MeSH:
Tumor Markers, Biological/metabolism;
Tumor Cells, Cultured;
Tissue Distribution;
Sensitivity and Specificity;
Reproducibility of Results;
Nephrons/metabolism;
Neoplasm Proteins/metabolism;
Membrane Proteins/analysis/*metabolism;
Kidney Neoplasms/*diagnosis/*metabolism;
Humans;
Carcinoma, Renal Cell/*diagnosis/*metabolism;
Adenoma, Oxyphilic/*diagnosis/*metabolism
- From:Journal of Korean Medical Science
2007;22(2):305-310
- CountryRepublic of Korea
- Language:English
-
Abstract:
Claudin-7 has recently been suggested to be a distal nephron marker. We tested the possibility that expression of claudin-7 could be used as a marker of renal tumors originating from the distal nephron. We examined the immunohistochemical expression of claudin-7 and parvalbumin in 239 renal tumors, including 179 clear cell renal cell carcinoma (RCC)s, 29 papillary RCCs, 20 chromophobe RCCs, and 11 renal oncocytomas. In addition, the methylation specific-PCR (MSP) of claudin-7 was performed. Claudin-7 and parvalbumin immunostains were positive in 3.4%, 7.8% of clear cell RCCs, 34.5%, 31.0% of papillary RCCs, 95.0%, 80.0% of chromophobe RCCs, and 72.7%, 81.8% of renal oncocytomas, respectively. The sensitivity and specificity of claudin-7 in diagnosing chromophobe RCC among subtypes of RCC were 95.0% and 92.3%. Those of parvalbumin were 80.0% and 88.9%. The expression pattern of claudin-7 was mostly diffuse in chromophobe RCC and was either focal or diffuse in oncocytoma. All of the cases examined in the MSP revealed the presence of unmethylated promoter of claudin-7 without regard to claudin-7 immunoreactivity. Hypermethylation of the promoter might not be the underlying mechanism for loss of its expression in RCC. Claudin-7 can be used as a useful diagnostic marker in diagnosing chromophobe RCC and oncocytoma.
