title: Low differentiated microvascular density and low expression of platelet-derived growth factor-BB (PDGF-BB) predict distant metastasis and poor prognosis in clear cell renal cell carcinoma.
abstract: OBJECTIVE
  To examine the prognostic significance of the expression of platelet-derived growth factor-BB (PDGF-BB) and differentiated microvascular density (MVD) in patients with clear cell renal cell carcinoma (ccRCC).
  
  
  METHODS
  We used the vascular marker cluster of differentiation 34 (CD34) to identify tumour blood vessels. The expression of PDGF-BB and CD34 was detected by immunohistochemistry (IHC) in tissue microarrays (TMAs) from 100 ccRCCs. Prognostic effects of individual parameters were calculated using Cox regression models and Harrell's concordance index (c-index).
  
  
  RESULTS
  Higher grade and more advanced stage ccRCCs had significantly less PDGF-BB expression and differentiated MVD (P < 0.05). Higher PDGF-BB expression was an independent prognostic factor for longer survival, and moreover, the final model built by the addition of PDGF-BB expression improved the predictive accuracy for disease-free survival (c-index 0.707) compared with the clinicopathological-based model (c-index 0.695). PDGF-BB expression was positively associated with differentiated MVD assessed by Spearman correlation and factor analysis (r = 0.634, P < 0.001).
  
  
  CONCLUSIONS
  PDGF-BB is as a novel and promising prognostic marker and antiangiogenic therapeutic target for the treatment of ccRCC.
authors.affiliation: Department of Genitourinary Oncology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China.
authors.forename: Lifeng
authors.initials: L
authors.lastname: Qi
authors.forename: Jun
authors.initials: J
authors.lastname: Du
authors.forename: Zhenting
authors.initials: Z
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Diao
authors.forename: Xusheng
authors.initials: X
authors.lastname: Chen
authors.forename: Xin
authors.initials: X
authors.lastname: Yao
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077214:Becaplermin; D002292:Carcinoma, Renal Cell / Q000098:blood supply* / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000098:blood supply* / Q000378:metabolism* / Q000473:pathology; D008297:Male; D055806:Microvessels; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009389:Neovascularization, Pathologic; D011237:Predictive Value of Tests; D011379:Prognosis; D020574:Proto-Oncogene Proteins c-sis / Q000096:biosynthesis*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D020574:Proto-Oncogene Proteins c-sis; D000077214:Becaplermin
keywords: antiangiogenetic therapy; clear cell renal cell carcinoma; metastasis; microvascular density; platelet-derived growth factor-BB; prognosis