title: Positive expression of HIF-2alpha/EPAS1 in invasive bladder cancer.
abstract: OBJECTIVE
  To investigate the expression of hypoxia-inducible factor (HIF)-2alpha/endothelial PAS domain protein 1 (EPAS1) in bladder cancer.
  
  
  METHODS
  Two bladder cancer cell lines (T24, EJ-1) were examined for the expression of HIF-2alpha/EPAS1 mRNA by reverse transcriptase-polymerase chain reaction and HIF-2alpha/EPAS1 protein by Western blot analysis, respectively. Expression of HIF-2alpha/EPAS1 protein was also investigated immunohistochemically on paraffin-embedded sections from 24 patients with bladder cancer.
  
  
  RESULTS
  HIF-2alpha/EPAS1 mRNA and protein could be detected in the two bladder cell lines under normoxia. The normal urothelium and all 7 superficial cases (pTis-pTa) were negative for HIF-2alpha/EPAS1. Five of the 8 pT1 cases (62.5%) and all 9 muscle-invasive cases were positive. The invasive compartment showed stronger HIF-2alpha/EPAS1 immunoreactivity compared with the superficial compartment. All the tumor clusters infiltrating to the interstitial tissue among muscle fibers showed moderate to strong positive staining.
  
  
  CONCLUSIONS
  HIF-2alpha/EPAS1 is mostly expressed in invasive bladder cancer, which indicates a possible role for HIF-2alpha/EPAS1 in the invasion of bladder cancer.
authors: Department of Urology and Reproductive Medicine, Graduate School Tokyo Medical and Dental University, Tokyo, Japan.
authors: Guangbin
authors: G
authors: Xia
authors: Yukio
authors: Y
authors: Kageyama
authors: Tetsuo
authors: T
authors: Hayashi
authors: Nobuhiko
authors: N
authors: Hyochi
authors: Satoru
authors: S
authors: Kawakami
authors: Kazunori
authors: K
authors: Kihara
mesh_terms: D000368:Aged; D051792:Basic Helix-Loop-Helix Proteins; D002295:Carcinoma, Transitional Cell / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D009363:Neoplasm Proteins / Q000032:analysis*; D012333:RNA, Messenger / Q000032:analysis; D015534:Trans-Activators / Q000032:analysis*; D014407:Tumor Cells, Cultured / Q000737:chemistry; D001749:Urinary Bladder Neoplasms / Q000737:chemistry* / Q000473:pathology; D000099162:Endothelial PAS Domain-Containing Protein 1
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D015534:Trans-Activators; D000099162:Endothelial PAS Domain-Containing Protein 1