ABSTRACT
Objective EGFR targeted therapy mediated by adeno-associated virus is a promising way to treat pancreatic cancer.This study aimed to assess the feasibility and activity of combining rAAV-anti EGFR,gemcitabine,and radiation in pancreatic cancer cells.Methods Aspc-1 human pancreatic carcinoma cells were divided into several groups,in vitro and in vivo,which were respectively exposed to gemcitabine alone,radiation alone,rAAV-anti EGFR alone,the combination of rAAV-anti EGFR with gemcitabine,the combination of rAAV-anti EGFR with radiation,and the combination of all three agents.The pancreatic cancer tumor growth and apoptotic rate were measured.Results The apoptotic rate was higher in cells treated with a single or combination of agents compared to the negative control (P＜0.05).The combination of rAAV-EGFR,gemcitabine,and radiation produced the highest induction of apoptosis compared to a single agent alone (P ＜ 0.05).Treatment with rAAV-anti EGFR greatly inhibited growth in the tumor xenografts (P＜0.05),and a synergistic effect of rAAV-anti EGFR,gemcitabine,and radiation was found.The number of tissue cancer cells that expressed cleaved caspase-3 after treatment with rAAV EGFR was more than that of the control group (P＜0.05).The combined treatment of rAAV-anti EGFR,gemcitabine,and radiation induced the highest numbers of cells expressing cleaved caspase-3 compared to that with a single agent alone (P＜0.05).Conclusions The rAAV-anti EGFR therapy in combination with chemotherapy and radiation therapy demonstrated a greater efficacy over therapy with a single agent alone.rAAV-anti EGFR increased the efficacy of gemcitabine and radiation in the treatment of pancreatic cancer cells.
ABSTRACT
Objective To construct a recombinant adeno-associated virus(rAAV)vector containing a human anti-epidermal growth factor receptor(anti-EGFR)single-chain variable fragment antibody gene,and observe its inhibitory effects on pancreatic cancer cell lines.Methods Human anti-EGFR single-chain variable fragment antibody gene was inserted into the Kpn I and Bgl Ⅱ sites to construct a rAAV-anti EGFR vector,and then rAAV1-EGFP group and rAAV1-anti EGFR group were established.The expression of anti-EGFR antibody was observed.Antibody expression was detected by Western blot,and the inhibition and apoptosis rates of human pancreatic cancer cell lines(PCT-3,SW1990,Capan-1,ASPC-1,MiaPaCa-2 and PANC-1 cells)were detected by CCK-8 assay and flow cytometry,respectively.All data were analyzed using the t test.Results The results of Western blot assay demonstrated that anti-EGFR antibody was expressed in 6 pancreatic cancer cell lines.The inhibition rates of rAAV1-EGFP and rAAVl-anti EGFR on pancreatic ASPC-1 cells were 1.1%± 2.4% and 15.1%±3.5%,respectively,with a significant difference between the 2 groups(t =6.598,P ＜0.05).The apoptosis rates of PANC-1 cells were 7.0% ± 3.0% in the rAAV1-EGFP group and 1 1.4% ± 2.5% in the rAAV1-anti EGFR group,with no significant difference between the 2 grouvs(t = 1.952,P ＞0.05).The apoptosis rates of SW1990,ASPC-1,Capan-1,PCT-3,MiaPaCa-2 cells were 1.1% ± 0.8%,1.5% ± 0.7%,1.7% ± 1.2%,1.1%±0.7% and 2.2% ± 1.1% in the rAAV1-EGFP group,and 17.6% ± 2.2%,46.9% ± 3.9%,20.0% ±2.8%,12.1% ± 1.6% and 31.1% ±2.5% in the rAAV1-anti EGFR group,respectively,with significant differences between the 2 groups(t = 12.208,19.846,10.405,10.909,18.327,P ＜0.05).Conclusions A rAAV-anti EGFR vector with human anti-EGFR single-chain variable fragment antibody gene was constructed.Anti-EGFR antibody has obvious inhibition effects on pancreatic cancer cell lines.