Tumor-derived Vascular Endothelial Growth Factor and Angiopoietin-2 in Non-small Cell Lung Cancer

Abstract

Lung cancer is a common disease with a dismal prognosis. Accurate staging is crucial for defining operability, selecting treatment regimens, and predicting survival. Methods of mediastinal lymph node staging include imaging and surgical sampling by different tools with many disadvantages. Angiogenesis is essential process in tumor growth, maintenance and metastasis. The tumor with high vessels density is related to metastasis and poor clinical outcome. Angiogenesis is regulated by balance between stimulatory and inhibitory regulators of endothelial cell activation. Vascular endothelial growth factor (VEGF) and Angiopoietin-2 (Ang-2) are two of the most potent angiogenic molecules. In this study we were evaluated the clinical effectiveness of serum level of Ang-2 and VEGF to aid management decision relating to diagnosis and staging of non-small cell lung cancer (NSCLC). The present work was conducted on 60 subjects. They were divided into 3 groups. Group 1 (15 healthy volunteers), Group 2 (15 patients with pulmonary diseases other than cancer) and Group 3 (30 patients with NSCLC).The latter were divided into two subgroups: Group 3a:15 patients with operable (NSCLC), and Group 3b:15 patients with non-operable NSCLC). Serum levels of Ang-2 and VEGF in different groups were measured using ELISA technique. The serum Ang-2 and VEGF were significantly higher in patients with NSCLC than patients with non-neoplastic lesions compared to healthy controls (p<0.001).There was a significant positive correlation between both levels in patients with NSCLC. With stage progression in NSCLC, the non-operable group (3b) had significantly higher levels than operable group (3a). Patients with distant metastasis had higher levels than those without (p< 0.001). But, no notable significant differences were found in either serum levels of VEGF or Ang-2 concerning the cell type .Among 30 NSCLC patients, stages of 7 patients (23.3%) were misdiagnosed because of they had normal sized lymph node on CT image . Five of them were Squamous carcinoma and the other two were adenocarcinoma on histopathological examination that need mediastioscopy. But, all NSCLC patients had high level of both markers according to their nodal staging. The operable group (3a)showed significant decrease in both levels after surgical resection (P<0.001). Conclusion:The present findings suggest that assessment of circulating levels of VEGF and Ang-2 may be simple noninvasive future tools for diagnosis, staging, treatment planning and monitoring of treatment in patients with NSCLC