Vascular endothelial growth factor level correlates with transforming growth factor-beta isoform levels in pleural effusions.
BACKGROUND
Recent studies have demonstrated high levels of vascular endothelial growth factor (VEGF) in exudative pleural effusions and a possible etiologic role. The factors regulating VEGF accumulation in the pleural space are unknown. Transforming growth factor (TGF)-beta is a potent stimulator of VEGF expression in vitro. We hypothesized that TGF-beta induces VEGF production in pleural tissues, and, hence, the pleural fluid VEGF levels should correlate with the levels of TGF-beta in pleural fluid of different etiologies.


METHODS
Seventy pleural fluid samples were analyzed. These included 20 malignant, 13 post-coronary artery bypass grafting (CABG), 8 parapneumonic, 11 miscellaneous exudative, and 18 congestive heart failure (CHF) pleural effusions.


RESULTS
Pleural fluid VEGF levels showed good correlation with those of TGF-beta(1) (r = 0.58; p < 0. 0001), TGF-beta(2) (r = 0.43; p < 0.001), and lactate dehydrogenase (r = 0.65; p < 0.001). The levels of TGF-beta(1) and TGF-beta(2) also were correlated (r = 0.60; p < 0.0001). The median levels of TGF-beta(1) (2,480 pg/mL) and TGF-beta(2) (266 pg/mL) in the CHF group were significantly lower than those in the malignant (TGF-beta(1), 4,902 pg/mL; TGF-beta(2), 428 pg/mL), post-CABG (TGF-beta(1), 5,456 pg/mL; TGF-beta(2), 377 pg/mL), parapneumonic (TGF-beta(1), 5,024 pg/mL; TGF-beta(2), 464 pg/mL), and miscellaneous exudate groups (TGF-beta(1), 7,690 pg/mL; TGF-beta(2), 369 pg/mL). There was no significant difference in TGF-beta(1) and TGF-beta(2) levels among the four exudate groups.


CONCLUSIONS
VEGF levels in pleural effusions are significantly correlated with the levels of TGF-beta(1) and beta(2) isoforms. VEGF, TGF-beta(1), and TGF-beta(2) levels were all higher in exudative effusions than in effusions secondary to CHF.
Cheng
D
D
Department of Pulmonary Medicine, St. Thomas Hospital, Vanderbilt University, Nashville, TN 37202, USA.
Lee
Y C
YC
Rogers
J T
JT
Perkett
E A
EA
Moyers
J P
JP
Rodriguez
R M
RM
Light
R W
RW
D016228:Endothelial Growth Factors / Q000032:analysis*; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D008222:Lymphokines / Q000032:analysis*; D010996:Pleural Effusion / Q000737:chemistry*; D016066:Pleural Effusion, Malignant / Q000737:chemistry; D020033:Protein Isoforms; D016212:Transforming Growth Factor beta / Q000032:analysis*; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D008222:Lymphokines; D020033:Protein Isoforms; D016212:Transforming Growth Factor beta; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D007770:L-Lactate Dehydrogenase