Epidermal growth factor receptor blockade with C225 plus gemcitabine results in regression of human pancreatic carcinoma growing orthotopically in nude mice by antiangiogenic mechanisms. Clin Cancer Res 2000 May;6(5):1936-48
Date
05/18/2000Pubmed ID
10815919Scopus ID
2-s2.0-18844473781 (requires institutional sign-in at Scopus site) 425 CitationsAbstract
Both epidermal growth factor receptor (EGF-R) signaling mechanisms and angiogenesis have been evaluated as independent targets for therapy of human pancreatic carcinoma, but a link between the two processes has been identified only recently. This study evaluated whether EGF-R blockade therapy with anti-EGF-R antibody C225 inhibits pancreatic carcinoma growth and metastasis in an orthotopic nude mouse model via tumor-mediated angiogenesis and whether gemcitabine potentiates this effect. In vitro treatment of human pancreatic carcinoma L3.6pl cells with C225 inhibited EGF-R autophosphorylation, producing a maximum of 20% cytostasis. Treatment with C225 plus gemcitabine resulted in additive cytotoxic effects that increased with increasing gemcitabine concentrations. Dose-dependent decreases in expression of the angiogenic factors vascular endothelial growth factor and interleukin 8 (but not basic fibroblast growth factor) were observed in the C225-treated cells (mRNA and protein levels). In L3.6pl tumors established in the pancreas of nude mice, systemic therapy with C225 alone and C225 in combination with gemcitabine resulted in growth inhibition, tumor regression, and abrogation of metastasis; median tumor volume was reduced from 538 to 0.3 and to 0 mm3, respectively. Gemcitabine treatment alone reduced median tumor volume from 538 to 152 mm3. Liver metastases were present in 50% of the controls, 30% of the gemcitabine-treated animals, and 20% of C225-treated animals. No macroscopically visible liver metastases were observed in the combination treatment group. As early as 11 days after C225 treatment, the median percentage of proliferating cell nuclear antigen-positive cells was substantially reduced compared with gemcitabine treatment alone (26% versus 73%, respectively) versus controls (92%), correlating with in vivo blockade of EGF-R activation. Similarly after 11 days treatment, production of vascular endothelial growth factor and interleukin 8 was significantly lower in C225 and C225 plus gemcitabine-treated tumors versus gemcitabine-treated and control tumors. Significant differences in microvessel density were observed 18 days after C225 or combination treatments (but not gemcitabine alone) in direct correlation with the difference in percentage of apoptotic endothelial cells, as visualized by double immunofluorescence microscopy. These experiments indicate that therapeutic strategies targeting EGF-R have a significant antitumor effect on human L3.6pl pancreatic carcinoma growing in nude mice which is mediated in part by inhibition of tumor-induced angiogenesis, leading to tumor cell apoptosis and regression. Furthermore, this effect is potentiated in combination with gemcitabine.
Author List
Bruns CJ, Harbison MT, Davis DW, Portera CA, Tsan R, McConkey DJ, Evans DB, Abbruzzese JL, Hicklin DJ, Radinsky RAuthor
Douglas B. Evans MD Chair, Professor in the Surgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsAntibodies, Monoclonal
Antibodies, Monoclonal, Humanized
Antineoplastic Combined Chemotherapy Protocols
Apoptosis
Cell Division
Cetuximab
Deoxycytidine
Endothelial Growth Factors
Epidermal Growth Factor
ErbB Receptors
Fluorescent Antibody Technique
Humans
Immunohistochemistry
In Situ Nick-End Labeling
Interleukin-8
Lymphokines
Male
Mice
Mice, Nude
Neoplasm Metastasis
Neoplasm Transplantation
Neovascularization, Pathologic
Pancreas
Pancreatic Neoplasms
Phosphorylation
Platelet Endothelial Cell Adhesion Molecule-1
Proliferating Cell Nuclear Antigen
Transplantation, Heterologous
Tumor Cells, Cultured
Vascular Endothelial Growth Factor A
Vascular Endothelial Growth Factors
