title: Indoleamine-pyrrole 2,3-dioxygenase might be a prognostic biomarker for patients with renal cell carcinoma.
abstract: OBJECTIVE
  To explore the role of indoleamine-pyrrole 2,3-dioxygenase (IDO), an immunomodulatory enzyme, in renal cell carcinoma (RCC).
  
  
  METHODS
  A total of 40 patients diagnosed as RCC in the Second Xiangya Hospital were included in this study. All patients received nephrectomy. The histopathological features of samples were assessed semi-quantitatively. IDO mRNA level in RCC and non-RCC renal tissues was determined by real-time quantitative PCR (RT-qPCR). And the expression of IDO protein in endothelial cells was examined by immunohistochemistry; a Kaplan-Meier survival curves was calculated on the basis of IDO mRNA level.
  
  
  RESULTS
  Level of IDO mRNA in RCC samples was significantly higher than that in tumor-free samples with P<0.001. Patients with high IDO expression had an significantly longer survival time than those with low IDO expression (P=0.01). There was a statistically significant inverse correlation between IDO and proliferation marker Ki67. Patients with high IDO level were of low Ki67 level, and vice versa (P<0.01).
  
  
  CONCLUSIONS
  IDO might be a prognostic biomarker for patients with RCC.
authors.affiliation: Department of Nephrology, Central South University, Changsha , China.
authors.forename: Fang
authors.initials: F
authors.lastname: Yuan
authors.forename: Yinghong
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiao
authors.initials: X
authors.lastname: Fu
authors.forename: Junxiang
authors.initials: J
authors.lastname: Chen
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D002292:Carcinoma, Renal Cell / Q000175:diagnosis / Q000201:enzymology* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000235:genetics / Q000378:metabolism*; D007680:Kidney Neoplasms / Q000175:diagnosis / Q000201:enzymology* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D012333:RNA, Messenger