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Updated: Jul 16, 2026

A Simple Bioassay for the Evaluation of Vascular Endothelial Growth Factors
Published on: March 15, 2016
Levels of soluble vascular endothelial growth factor receptor 1 are elevated in the exudative pleural effusions
Hideki Tomimoto1, Seiji Yano, Hiroaki Muguruma
1Department of Internal Medicine and Molecular Therapeutics, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan.
Purpose:
Vascular endothelial growth factor (VEGF) plays a critical role in the production of malignant pleural effusions. In the present study, we examined the levels of soluble VEGF receptor-1 (sVEGFR-1) and angiopoietin-2 (Ang-2), as possible regulators of VEGF activity, in transudative and exudative pleural effusions.
Methods:
Forty-two patients were included in this study: 4 with transudative pleural effusions due to heart failure (HF), 38 with exudative pleural effusions (lung cancer [LC], 22; other malignant diseases [MD], 10; tuberculosis [TB], 6). The levels of VEGF, Ang-2, and sVEGFR-1 in the pleural effusions were measured by an enzyme-linked immunosorbent assay.
Results:
The levels of VEGF, Ang-2, and sVEGFR-1 in exudative effusions were higher than those in transudative effusions. Interestingly, the levels of VEGF and Ang-2 in bloody effusions were significantly higher than those in non-bloody effusions (p < 0.05), but the level of sVEGFR-1 in bloody effusions was lower than that in non-bloody effusions. The levels of VEGF and Ang-2 were significantly higher in the malignant effusions, compared with effusion from HF and TB (p < 0.05). In addition, sVEGFR-1 was significantly higher in the effusion from LC, MD, and TB compared with effusion from HF (p < 0.05). In the malignant effusions, direct correlations were observed among VEGF, sVEGFR-1, and Ang-2.
Conclusions:
The sVEGFR-1 levels were elevated in exudative pleural effusions, and were lower in bloody effusions than in non-bloody effusions, thus suggesting the regulatory role of sVEGFR-1 in the exudative pleural effusions.
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