Pathological characterization of Kank in renal cell carcinoma.

The Kank gene was found as a candidate tumor suppressor gene at 9p24 by loss-of-heterozygosity search in renal cell carcinoma (RCC) and seems to have a role in controlling the formation of the cytoskeleton through the polymerization of actin. Here, we characterized the Kank protein in renal tubular cells as well as other glandular cells in the colon, stomach, prostate, testis, pancreas, thyroid, uterus, submandibular gland, adrenal, duodenum, and esophagus, and specific cells such as hepatic, alveolar myocardial, and glial cells by using a monoclonal antibody against Kank. Loss of expression of Kank in one RCC sample was detected by immunohistochemical and Western blot analyses while expression of CDKN2A (p16/Ink4A) was retained in the sample. The expression of Kank in the cytoplasm and at the sites of membrane ruffling in HEK293 and VMRC-RCW cells and in a primary culture of renal tubular cells was also detected by fluorescence-based immunostaining.