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Erschienen in: Surgical Endoscopy 10/2010

01.10.2010

Minimally invasive colorectal resection for cancer is associated with a short-lived decrease in soluble Tie-2 receptor levels, which may transiently inhibit VEGF-mediated angiogenesis (via altered blood levels of free Ang-1 and Ang-2)

verfasst von: H. M. C. Shantha Kumara, Michael J. Grieco, Xiaohong Yan, Matthew F. Kalady, Vincent DiMaggio, Donald G. Kim, Neil Hyman, Daniel L. Feingold, Richard L. Whelan

Erschienen in: Surgical Endoscopy | Ausgabe 10/2010

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Abstract

Background

Angiopoetin- (Ang-) 1 inhibits and Ang-2 promotes VEGF-mediated angiogenesis via binding to endothelial cell-bound Tie-2 receptor (Tie-2). After minimally invasive colorectal resection (MICR), Ang-1 levels decrease and Ang-2 levels increase, which may stimulate angiogenesis in wounds and residual tumor foci. Soluble Tie-2 (sTie-2) modulates the effects of free Ang-1 and Ang-2 by binding to them. This study assessed perioperative MICR plasma sTie-2 levels.

Methods

Blood samples were taken preoperatively (PreOp) and on postoperative days (POD) 1 and 3 from 50 cancer and 53 benign disease MICR patients. In a subgroup, a fourth sample was taken between POD7 and POD13 and bundled as a single time point. sTie-2 levels (ng/ml) were determined via ELISA. The mean and SD were determined at each time point. The t test used for analysis.

Results

PreOp plasma sTie-2 levels were significantly higher in the benign group (27.6 ± 10.2) than in the cancer group (22.9 ± 7.9). A significant drop from PreOp occurred in sTie-2 levels in the cancer group on POD1 (20.0 ± 7.4) and POD3 (21.0 ± 6.6) and in the benign group on POD1 (24.8 ± 9.1). The benign group’s POD3 and the cancer group’s POD7-13 sTie-2 levels were statistically similar to the PreOp levels while the benign group’s POD7-13 level was significantly higher.

Conclusion

PreOp sTie-2 levels were significantly lower in cancer patients. MICR is associated with a significant short-lived decrease in plasma sTie-2 levels in cancer patients on POD1 and 3, which may briefly inhibit VEGF-mediated angiogenesis. The benign group’s early results were similar.
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Metadaten
Titel
Minimally invasive colorectal resection for cancer is associated with a short-lived decrease in soluble Tie-2 receptor levels, which may transiently inhibit VEGF-mediated angiogenesis (via altered blood levels of free Ang-1 and Ang-2)
verfasst von
H. M. C. Shantha Kumara
Michael J. Grieco
Xiaohong Yan
Matthew F. Kalady
Vincent DiMaggio
Donald G. Kim
Neil Hyman
Daniel L. Feingold
Richard L. Whelan
Publikationsdatum
01.10.2010
Verlag
Springer-Verlag
Erschienen in
Surgical Endoscopy / Ausgabe 10/2010
Print ISSN: 0930-2794
Elektronische ISSN: 1432-2218
DOI
https://doi.org/10.1007/s00464-010-1008-z

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