Clinical significance of levels of serum endostatin and vascular endothelial growth factor in smokers

Objective To explore the changes and clinical significance of levels of serum vascular endothelial growth factor(VEGF)and endostatin in smokers. Methods In a case-control study,levels of serum VEGF and endostatin were determined in 82 smokers with lung cancer,82 pair-matched smokers without lung cancer and 20 healthy non-smokers by enzyme-linked immunoabsent assay(ELISA) or competitive enzyme immunoassay.Results The level of serum VEGF in smokers with lung anncer[(16.1±7.9)ng/ml]was markedly higher than that in the other two groups(both P＜0.01).The level of serum VEGF in smokers without lung cancer was significantly higher than that in healthy non-smokers(P＜0.05).The level of serum endostatin in smokers with lung cancer was significantly higher than that in healthy nonsmokers(P＜0.01),but was not significantly different from that in smokers without lung cancer(P＞0.05),and that in smokers without lung cancer was significantly higher than that in healthy non-smokers (P＜0.05).Notably,the ratio of endostatin to VEGF in smokers with lung cancer(1.3±0.5)was significantly lower than that in the other two groups(both P＜0.01).However.there was no significant difference in it between smokers without lung cancer and healthy non-smokers(P＞0.05).The level of serum VEGF correlated significantly to that of endostatin in smokers both with and without lung cancer(P＜0.01).Conclusions These findings suggest that smoking may result in imbalance of levels of serum endostatin and VEGF leading to tumorigenesis.The ratio of endostatin to VEGF can be used as an early diagnostic indicator for lung cancer in smokers.Periodic determination of levels of serum VEGF and endostatin as well as the ratio of endostatin to VEGF is of clinical importance. Key words: Endothelium,vascular;  Endothelial growth factors; Lung neoplasms