Observation Of Synergistic Effect Of Endostatin And Cisplatin On Calu-6 Cell

Objective: Recently, the incidence and mortality of lung cancer continue to increase and get highest in all of malignancy. About 80% of them are non- small cell lung cancer and 50% of patients given the diagnosis of NSCLC belong to advanced disease. Chemotherapy plays a key role in treatment of advanced NSCLC. But, efficacy of chemotherapy is very limited and the phenomenon of drug resistance in NSCLC is very common. 1971 the professor Folkman firstly proposed the theory of tumor depending on angiogenesis. He proposed that the angiogenesis was essential not only in tumor growth, but also in tumor invasion and metastasis. Antiangiogenesis become the first light of morning in tumor therapy. Endostatin is an endogenous inhibitor of angiogenesis, specifically acting on endothelial cells, inhibiting it's migration, inducing it's apoptosis, thus inhibiting the forming of new vessels and tumor growth. Recently some research indicated that Endostatin can directly inhibit tumor cell growth, but the mechanism of action and signal conduction pathway is not very clear. Endostar is the new recombinated human endostatin. Clinical trial results indicated that it had a good perspective on clinical application and synergetic effect with chemotherapy. But it is not clear about the synergetic mechanism, action characteristic and best regimen. We choosing Calu-6, the human lung adenocarcinoma cell, to observe the effects of Endostatin and Endostar on human lung cancer cells (Calu-6) proliferation and the apoptosis- induced effects and apoptosis associated mechanism. To observe the synergistic inhibiting effects of Endostatin, Endostar and Cisplatin on Calu-6 cells proliferation. If synergistic effect was defined, we further investigate the optimistic time or dose of the combination regimen and the possible mechanism. To assess whether or not the effects of two Endostatins (Endostar, Endostatin) are different.Methods:The inhibiting effects of Endostatin and Cisplatin on Calu-6 cells proliferation were studied by MTT assay. The cell apoptosis was measured by cell flow cytometry (FCM).The expression of apoptosis associated protein (Bcl-2/Bax,sFas/sFasL) was analyzed by enzyme linked immunosorbent assay (ELISA).Results: Endostatin can inhibit Calu-6 cell proliferation (P<0.05) on time-dependence; no any evidence for its effect on dosage-dependant has been proved, however, an optimistic dosage revealed. Also it can induce apoptosis by down-regulating the expression of Bcl-2 without obvious effect on Bax. The expression of sFas/sFasL hasn't been found. Among combinative protocol, simultaneous administration of Endostatin and Cisplatin represented more obvious effect on inducing apoptosis and down-regulating Bcl-2 than Cisplatin alone. Successive administration represented no obvious effect than Cisplatin. There was no significant difference on effect between Endostar and Endostatin.Conclusions:Cisplatin inhibit growth of Calu-6 cell on time-dependence and dose-dependence. Endostatin inhibit growth of Calu-6 cell on time-dependence and have an optimistic dosage .Both of them can induce cell apoptosis with the mechanism concerned with the down-regulation of Bcl-2 without obvious effect on Bax. The expression of sFas/sFasL hasn't been found. It still need more efforts to investigate. Among combinative protocol, simultaneous administration of Endostatin and Cisplatin represented more obvious effect on inducing apoptosis and down-regulating Bcl-2 than Cisplatin alone. Successive administration represented no obvious effect than Cisplatin. The mechanisms of Endostatins' effect are similar. It can point out to draw up the common principle of endostatin to guide clinical action.