title: VEGFR-1 Expression Relates to Fuhrman Nuclear Grade of Clear Cell Renal Cell Carcinoma.
abstract: BACKGROUND
  Increasing evidence suggests that vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) 1 signaling may play an important role in the progression of pathological angiogenesis that occurs in many tumors, including renal cell carcinoma (RCC). Therapeutic targeting directed against VEGF and VEGFR-2 has been proven to be successful for metastatic clear cell RCC (CCRCC). However, the expression of VEGFR-1 and its association with prognostic parameters of CCRCC in the tumorigenesis of renal cancer remains unclear. Therefore, we examined the expression of VEGFR-1 and its prognostic significance in CCRCC.
  
  
  METHODS
  Immunohistochemical staining for VEGFR-1 was performed on 126 formalin-fixed paraffin-embedded CCRCC tissue samples. Six of these cases were available for Western blot analyses. The results were compared with various clinicopathologic parameters of CCRCC and patients' survival.
  
  
  RESULTS
  VEGFR-1 expression was detected in 59 cases (46.8%) of CCRCC. Higher VEGFR-1 expression was significantly correlated with a lower Fuhrman nuclear grade and the absence of renal pelvis invasion, although it was not related to patients' survival. Western blot analyses showed higher VEGFR-1 expression in low grade tumors.
  
  
  CONCLUSIONS
  VEGFR-1 expression may be associated with favorable prognostic factors, particularly a lower Fuhrman nuclear grade in CCRCC.
authors.affiliation: Departments of Pathology, Yonsei University Wonju College of Medicine, Wonju, Korea.
authors.forename: Sayamaa
authors.initials: S
authors.lastname: Lkhagvadorj
authors.affiliation: Occupational & Environmental Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.
authors.forename: Sung Soo
authors.initials: SS
authors.lastname: Oh
authors.affiliation: Departments of Pathology, Yonsei University Wonju College of Medicine, Wonju, Korea.
authors.forename: Mi-Ra
authors.initials: MR
authors.lastname: Lee
authors.affiliation: Urology, Yonsei University Wonju College of Medicine, Wonju, Korea.
authors.forename: Jae Hung
authors.initials: JH
authors.lastname: Jung
authors.affiliation: Urology, Yonsei University Wonju College of Medicine, Wonju, Korea.
authors.forename: Hyun Chul
authors.initials: HC
authors.lastname: Chung
authors.affiliation: Physiology, Yonsei University Wonju College of Medicine, Wonju, Korea ; Institute of Lifestyle Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.
authors.forename: Seung-Kuy
authors.initials: SK
authors.lastname: Cha
authors.affiliation: Departments of Pathology, Yonsei University Wonju College of Medicine, Wonju, Korea.
authors.forename: Minseob
authors.initials: M
authors.lastname: Eom
keywords: Clear Cell Renal Carcinoma; Immunohistochemistry; Prognosis; VEGFR-1; Western blotting