The Clinical Significance Of Activated Circulating Endothelial Cells In The Peripheral Blood Of NSCLC Patients Treated With Chemotherapy

Backgroud Angiogenesis not only provides the nutrients of metabolism for the tumor growth, also plays a critical role in progression and metastasis of various solid tumors. Anti-angiogenic drugs, alone or in combination with chemotherapeutics, are increasingly used by medical oncologists, including NSCLC. The evaluation of microvessel density (MVD) in cancer biopsy samples, the levels of angiogenic growth factors such as VEGF, b-FGF or HGF, and functional imaging such as dynamic contrast magnetic resonance imaging (DCE-MRI), don't well to identify tumor angiogenesis condition and anti-angiogenic therapies effect,and not fully validated for clinical studies. The concept of angiogenesis has evolved from a simple model of the formation of new blood vessels from the preexisting vasculature into a multifaceted process in which, beyond CECs, bone marrow-derived EPCs contribute to neovascularization. Moreover, various cytokines contribute to tumor neovascularization, including VEGF. CECs play a critical role in supporting tumor angiogenesis and growth. CECs are increased in cancer patients,and more numerous and viable compared with healthy subjects, and the CECs numbers are reduced to normal values in patients achieving CR. CECs represent a surrogate biomarkers with angiogenesis and antiangiogenic drug activity. About the method of CECs examination, Hladovec'method, PVP-silica and Percoll density gradients method to the CECs research have a huge promotion effect in early. The immunology methods including imMunomagnetic bead separation(IMS) and flow cytometry are the most widely and effective method to separates and appraises CECs at present. Flow cytometry has become principal method widely to apply the CECs examination to substitute IMS, through endothelial cell antibodys having different fluorescein marks. In recent studies, CECs are divided into resting CECs, apoptotic CECs and aCECs, most of CECs are resting and apoptotic CECs, little of them are aCECs. The aCECs may well reflect angiogenic activity.At present, the studies of CECs in NSCLC to reflect the tumor angiogenesis and anti-angiogenic therapies effect are not too much, the influence of angiogenesis and CECs, aCECs in NSCLC by chemotherapy are particularly less. Therefore, it has very important meaning to measure the change of CECs and aCECs in NSCLC by chemotherapy.Objective:1. To establish the flow cytometric method for CECs and aCECs.2. Find out the quantitative difference of CECs and aCECs between NSCLC patients and healthy controls.3. Find out the clinical significance of the counts of peripheral CECs and aCECs in patients with NSCLC by chemotherapy.Methods:Adopted the method of Lymphocyte separation to prepare mononuclear cell sample, CECs and aCECs were enumerated in 64 NSCLC patients and 30 healthy controls by flow cytometry using PC5-labelled anti-CD45, FITC-labelled anti-CD106 and PE-labelled anti-CD146. CECs are difined as CD45-/dim and CD146+ cells, aCECs are difined as CD45-/dim, CD 146+ and CD 106+ cells.Results:1. Adopting this method could successfully detect the number of CECs and aCECs.2. The counts of CECs and aCECs were significantly higher in NSCLC patients than in healthy controls(P=0.000). CECs in little cases were aCECs, the aCECs percentage was higher in NSCLC patients than in healthy volunteers(P=0.000).3. There was no difference in the counts of CECs and aCECs to pathology type in NSCLC patients, and we did not detect the correlation between the CECs, aCECs counts and tumor sizes, blood CEA, as well as the serum level of VEGF in NSCLC patients (P=0.938,0.829; 0.150,0.124; 0.697,0.631).4. The aCECs counts were significantly increased by chemotherapy as compared with pretreatment in NSCLC patients(P=0.031).5. In different chemotherapeutics, the CECs and aCECs counts were significantly increased as compared with pretreatment by AP scheme(P=0.006,0.034).6. CECs and aCECs were increased as compared with pretreatment in SD and PD patients(SD:P=0.030,0.021; PD:P=0.036,0.028). The aCECs count were significantly higher in SD and PD patients than in patients with CR+PR(P=0.032,0.012).Conclusion:1. Adopting this method can rapidly and conveniently detect the number of CECs and aCECs.2. The CECs and aCECs significantly increase in NSCLC patients.3. The pure chemotherapeutics caused CECs and aCECs to elevate particularly in NSCLC patient, concerned with the different chemotherapeutics schemes and effect.4. CECs and aCECs may be suggested as surrogate biomarkers of angiogenesis and prognosis in NSCLC.