Expression of S100 protein family members in the pathogenesis of bladder tumors

The S100 proteins act as multifactional signaling factors that are involved in the regulation of diverse cellular processes. To explore the involvement of S100 genes in bladder cancers, S100 gene expressions were systematically evaluated at the RNA level by microarray and real-time PCR. Total RNAs were obtained from 4-hydroxybutyl(butyl)nitrosamine (OH-BBN)-induced mouse and rat bladder cancers, human bladder cancers and matched normal bladder urothelium. Microarray analysis was performed on mouse and rat bladder cancers; real-time PCR was performed in mouse, rat and human bladder cancers and their matched normal urothelium for confirmation. Microarray analysis revealed that 9 and 6 members of the S100 gene family were differentially expressed in mouse and rat bladder cancers, respectively. Thirteen members of the S100 gene family were confirmed by real-time PCR to be differentially expressed in human bladder cancers, with overexpression of S100A2, S100A3, S100A5, S100A7, S100A8, S100A9, S100A14, S100A15, S100A16 and S100P, and underexpression of S100A1, S100A4 and S100B. S100A1, S10OA3, S100A8, S10A9, S100A14, S100A15 and S100A16 showed similar patterns of differential expression in bladder cancers from mouse, rat and human. To our knowledge this is the first report of systematic evaluation of S100 gene expressions in bladder cancers. Our results indicate that differential expression of S100 gene family members is characteristic of bladder cancers and these genes may play important roles in bladder tumorigenesis and progression

Renal Cell Neoplasms of Oncocytosis Have Distinct Morphologic, Immunohistochemical, and Cytogenetic Profiles

This study was undertaken to elucidate the genetic patterns of the renal cell neoplasms of oncocytosis and to compare them with those found in cases with multiple oncocytomas. Three cases of renal oncocytosis and 6 cases of multiple oncocytomas were analyzed. Fluorescence in situ hybridization analysis was performed with centromeric probes for chromosomes 1, 2, 6, 10, and 17 that are typically lost in chromophobe renal cell carcinoma but not in oncocytoma. Immunohistochemistry for cytokeratin 7, parvalbumin, and S100A1 was performed in all cases. Eleven tumors were present in the 3 kidneys with oncocytosis. One of these was a classic chromophobe renal cell carcinoma. In the other 10, none showed any chromosomal losses, whereas 3 showed gains of all 5 chromosomes and 1 had gains of chromosomes 2 and 10. The chromophobe renal cell carcinoma showed losses of chromosome 1, 6, 10, and 17. Twelve of 14 tumors from the patients with multiple oncocytomas showed no loss of any of the chromosomes 1, 2, 6, 10, or 17 and 2 had loss of chromosome 1. All the tumors from kidneys with renal oncocytosis showed strong parvalbumin immunoreactivity, whereas cytokeratin 7 and S100A1 expression were variable. In summary, the renal cell neoplasms of oncocytosis seem to have distinct morphologic, immunohistochemical, and cytogenetic profiles and likely are a distinct entity, not closely related to oncocytoma or chromophobe renal cell carcinoma