Investigation of a plasmid containing a novel immunotoxin VEGF165-PE38 gene for antiangiogenic therapy in a malignant glioma model.
Inhibition of tumor neovascularization has profound effects on the growth of solid tumors. Our previous studies have shown the effect of VEGF165-PE38 recombinant immunotoxin on proliferation and apoptosis in human umbilical vein endothelial cells in vitro. In this study, we explored the direct inhibition of angiogenesis in chick chorioallantoic membrane and antiangiogenic therapy in a malignant glioma model. HEK293 cells were transfected with the pVEGF165PE38-IRES2-EGFP plasmid. ELISA was used to confirm the expression of VEGF165-PE38 in the transfected cells. These cells released 1396 + or - 131.9 pg VEGF165-PE38/1x10(4) cells/48 h into the culture medium and the supernatant was capable of inhibiting the growth of capillary-like structures in chick chorioallantoic membrane assay. In a murine malignant glioma model, plasmid was directly administered via multiple local intratumoral delivery. After day 16 the tumor volume in mice treated with pVEGF165PE38-IRES2-EGFP was significantly lower than that in mice in the control groups. Immunohistochemistry studies showed that the treated group had decreased expression of CD31. Quantitative analysis of microvessel density in the treated group was 1.99 + or - 0.69/0.74 mm(2), and was significantly lower than that in the control groups (9.33 + or - 1.99/0.74 mm(2), 8.09 + or - 1.39/0.74 mm(2) and 8.49 + or - 1.69/0.74 mm(2)). Immunohistochemistry analysis indicated that immunotoxin VEGF165-PE38 was distributed in the treated group in malignant glioma tissue. Our findings provide evidence that the in vivo production of VEGF165-PE38 through gene therapy using a eukaryotic expression plasmid had potential antiangiogenic activity in malignant glioma in vivo.
Hu
Chang-chen
CC
Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China.
Ji
Hong-ming
HM
Chen
Sheng-li
SL
Zhang
Han-wei
HW
Wang
Bin-quan
BQ
Zhou
Li-yuan
LY
Zhang
Zi-ping
ZP
Sun
Xin-lin
XL
Chen
Zhen-zhou
ZZ
Cai
Ying-qian
YQ
Qin
Ling-sha
LS
Lu
Li
L
Jiang
Xiao-dan
XD
Xu
Ru-xiang
RX
Ke
Yi-quan
YQ
D036002:ADP Ribose Transferases / Q000627:therapeutic use; D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D000818:Animals; D001427:Bacterial Toxins / Q000627:therapeutic use; D045744:Cell Line, Tumor; D005098:Exotoxins / Q000627:therapeutic use; D005240:Feasibility Studies; D015316:Genetic Therapy; D005910:Glioma / Q000098:blood supply / Q000628:therapy*; D006801:Humans; D000922:Immunotoxins / Q000627:therapeutic use*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D010957:Plasmids; D011549:Pseudomonas / Q000378:metabolism; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics*; D037521:Virulence Factors / Q000627:therapeutic use; D023041:Xenograft Model Antitumor Assays; D000097668:Pseudomonas aeruginosa Exotoxin A
D036002:ADP Ribose Transferases; D020533:Angiogenesis Inhibitors; D001427:Bacterial Toxins; D005098:Exotoxins; D000922:Immunotoxins; D042461:Vascular Endothelial Growth Factor A; D037521:Virulence Factors; D000097668:Pseudomonas aeruginosa Exotoxin A; C467484:VEGFA protein, human