title: Expressions and Clinical Significances of Angiopoietin-1, Angiopoietin-2, and Tie-2 Receptor in Patients With Colorectal Cancer.
abstract: OBJECTIVE
  Angiopoietin-1 (Ang-1) plays a crucial role in vascular and hematopoietic development, mainly through its cognate receptor, Tie-2. Increased levels of Ang-2 have been shown to be correlated with abnormal tumor angiogenesis in several malignancies. Hence, we estimated the increased expression of Ang-2 relative to Ang-1 in patients with colorectal cancer and correlated our finding with prognosis in order to investigate the relationships between the expressions of Ang-1/Ang-2/Tie-2 receptor and the clinical parameters or overall survival of such patients.
  
  
  METHODS
  We retrospectively analyzed 114 tissue samples from patients with colorectal cancer by using immunohistochemistry (IHC) to examine Ang-1, Ang-2, and Tie-2 expressions and to investigate the relationship between those expressions and clinical parameters or overall survival of such patients. A Western blot analysis was used for Ang-2 expression.
  
  
  RESULTS
  IHC staining showed a link between Ang-1 and Tie-2 (P = 0.018), as well as meaningful correlations between Ang-2 and Tie-2 receptor (P = 0.022) and between lymph-node metastasis and Ang-2 (P = 0.025). The stronger the IHC staining for Ang-2 expression was, the shorter the cumulative survival was (P = 0.016).
  
  
  CONCLUSIONS
  A relationship was found to exist between Ang-2 and Tie-2 expressions. The Ang-2 was correlated with lymph-node metastasis, and high expression of Ang-2 was indicative of poor overall survival. These findings suggest that Ang-2 is a useful prognostic marker in the management of patients with colorectal cancer. In addition, we suggest that Ang/Tie-2 signaling plays an important role in the progression of colorectal cancer.
authors.affiliation: Department of Surgery, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
authors.forename: Sunghoon
authors.initials: S
authors.lastname: Hong
authors.affiliation: Department of Surgery, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
authors.forename: Hae Il
authors.initials: HI
authors.lastname: Jung
authors.affiliation: Department of Surgery, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
authors.forename: Tae Sung
authors.initials: TS
authors.lastname: Ahn
authors.affiliation: Division of Hematology and Oncology, Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
authors.forename: Han-Jo
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Division of Hematology and Oncology, Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
authors.forename: Kyu-Taek
authors.initials: KT
authors.lastname: Lee
authors.affiliation: Department of Surgery, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
authors.forename: Moo-Jun
authors.initials: MJ
authors.lastname: Baek
authors.affiliation: Division of Hematology and Oncology, Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
authors.forename: Sang-Byung
authors.initials: SB
authors.lastname: Bae
keywords: Angiopoietins; Colorectal neoplasms; Prognosis; TIE-2 receptor