Antitumor Treatment Efficiency By Targeting Epidermal Growth Factor Receptor And Vascular Endothelial Growth Factor Receptor-2 In An Orthotopic Human Glioblastoma Model

Partâ… Exploring the effect on tumor growth and angiogenesis after AG1478 combined with chemotherapy for treating the orthotopic xenografts of human glioblastoma in nude miceObjective To evaluate the efficacy of antitumor activity and influence on angiogenesis after AG1478 combined with Cisplatin for treating the orthotopic xenografts of human gliobastoma multiforme.Methords Establishing orthotopic xenograft model of human gliobastoma multiforme with stable EGFR expression as described previously.On day 3 postinnoculation,40 mice were divided into 4 groups randomly with 10 every group,then 4 groups of mice received i.p. injections of AG1478(25mg/kg every time),Cisplatin (3mg/kg every time),AG1478+ Cisplatin(25mg/kg every time +3mg/kg every time)and PBS(0.1ml/20g every time)respectively with every 2 days for 4 times,then survival time were observed until mice bearing xenografts were natural death.The experiment was repeated,in which the same types of treatment were initiated on day 3.On day 14 after innnoculation ,every group of mice were sacrificed. Mouse brains were removed from the cranial cavity, fixed in formalin, bisected coronally, and embedded in paraffin.Serial sections were stained with H&E,then tumor appearance and volume were observed and measured.The expression of EGFR,phosphorylated EGFR (P-EGFR) were detected by immunochemical or Western blot methods;VEGF,IL-8 or Ki-67 in the xenografts were detected by immunochemical methods,and apoptosis were detected by TUNEL method.Results The expression of P-EGFR were decreased because phosphorylation of EGFR were inhibited by AG1478,accordingly the expression of VEGF or IL-8 were decreased,and microvessel destiny was also declined.Compared with PBS group,the suvival were strikingly prolonged,and volume of xenografts were reduced by the combination of Cisplatin with AG1478;meanwhile, the combined application could significantly decrease proliferative activity and increase apoptotic rate,but no effect in drugs alone.Conclusion The combination of AG1478 with Cisplatin significantly increased the activities against tumor growth and inhibited the angiogenesis,which provided a rationale for its clinical evaluation in combination with both chemotherapy and other molecular target drugs for treating malignant gliomas.Partâ…¡Antitumor treatment efficiency by targeting epidermal growth factor receptor and vascular endothelial growth factor receptor-2 in an orthotopic human glioblastoma modelObjective: To explore the inhibitive effect on transplanted tumor of human glioblastoma multiforme in the brain of nude mice after t reatment of C225 and DC101 alone and combined application.Methods: Establishing the human GBM orthotopic models with high expression of EGFR and VEFR in the brain of nude according to the previous method.On day 3 postinnoculation,40 mice were divided into 4 groups randomly with 10 every group,then 4 groups of mice received i.p. injections of C225(50mg/kg),DC101(40mg/kg),CD225+DC101 (50 +40)mg/kg or PBS(0.1ml/20g)respectively with every 2 days for 4 times.On day 14 after innnoculation ,every group of mice were killed.Mouse brains were removed from the cranial cavity, fixed in formalin, bisected coronally, and embedded in paraffin. Serial sections were stained with H&E to observe tumor appearance and to measure the maximum or minimun diameter under light microscope so as to work out tumor volume.The expression of MMP1,MVD or Ki-67 were detected by immunochemical methods,and apoptosis were detected by TUNEL method.Results:When compared with controls(PBS) group,the xenograft volumes were decreased by 59.7% and 62.9% in the DC101 and the DC101+C225 group respectively(P<0.05),but no effect in the C225group(P>0.05);The invasion ability of xenograft was improved,and expression of MMP1 was increased to (++) in the DC101group. The invasion ability of xenograft was declined,and expression of MMP1 was decreased to (+) in the C225 group,which was also founded in the DC101+C225 group.MVD were reduced by 64% and 68% in the DC101 and the DC101+C225 group respectively(P<0.05), but no effect in the C225group(P>0.05);Ki-67 labelling index(LI) was decreased by 53.2% and 56.4% in the DC101 and the DC101+C225 group respectively(P<0.05), but no effect in the C225 group(P>0.05);Apoptotic index(AI) was increased by 66.7% and 75% in the DC101 and the DC101+C225 group respectively(P<0.05), but no effect in the C225 group(P>0.05).Results:The combined C225 and DC101 can inhibit the growth and invasion ability of transplanted tumor of human glioblastoma multiforme in nude mice. The effect of C225 + DC101 is better than that of C225 and DC101 alone,which provided a experimental foundation for treatmenting malignant glioma by the method of unifying drugs with different pharmacological features.