Antiangiogenic and antitumor activity of anti-epidermal growth factor receptor C225 monoclonal antibody in combination with vascular endothelial growth factor antisense oligonucleotide in human GEO colon cancer cells.
Angiogenesis plays a key role in tumor growth and metastasis. The transforming growth factor alpha (TGF-alpha)-epidermal growth factor receptor (EGFR) autocrine pathway controls in part the production of angiogenic factors such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in cancer cells. In this study, we have evaluated the antiangiogenic and antitumor activity of monoclonal antibody (MAb) C225, an anti-EGFR chimeric human-mouse MAb, alone and in combination with a human VEGF antisense (AS) 21-mer phosphorothioate oligonucleotide (VEGF-AS) in human GEO colon cancer cells. MAb C225 treatment determined a dose-dependent inhibition of VEGF, bFGF, and TGF-alpha production by GEO cells in vitro. Treatment with VEGF-AS caused a selective inhibition in VEGF expression by GEO cells in vitro. Treatment of immunodeficient mice bearing established, palpable GEO xenografts for 3 weeks with VEGF-AS or with MAb C225 determined a cytostatic reversible inhibition of tumor growth. In contrast, a prolonged inhibition of tumor growth was observed in all mice treated with the two agents, in combination with a significant improvement in mice survival compared with controls (P < .001), to MAb C225 (P < .001), or to VEGF-AS (P < .001) treated mice. All mice died within 4, 6, and 8 weeks after tumor cell injection in the control, VEGF-AS and MAb C225 groups, respectively. In contrast, 50% of mice treated with the combination of VEGF-AS and MAb C225 were alive at 13 weeks. Ten % of mice treated with VEGF-AS plus MAb C225 were alive at 20 weeks and had no histological evidence of GEO tumors. Immunohistochemical analysis of GEO tumor xenografts demonstrated a significant reduction of VEGF expression after treatment with VEGF-AS with a parallel reduction in microvessel count. MAb C225 treatment determined a reduction in the expression of VEGF, bFGF, and TGF-alpha with a reduction in microvessel count. Finally, a significant potentiation in inhibition of VEGF expression and little or no microvessels were observed in GEO tumors after the combined treatment with the two agents.
Ciardiello
F
F
Cattedra di Oncologia Medica, Dipartimento di Endocrinologia e Oncologia Molecolare e Clinica, Facoltà di Medicina e Chirurgia, Università degli Studi di Napoli Federico II, Naples, Italy. fortunatociardiello@yahoo.com
Bianco
R
R
Damiano
V
V
Fontanini
G
G
Caputo
R
R
Pomatico
G
G
De Placido
S
S
Bianco
A R
AR
Mendelsohn
J
J
Tortora
G
G
D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D015153:Blotting, Western; D003110:Colonic Neoplasms / Q000098:blood supply / Q000378:metabolism / Q000628:therapy*; D004305:Dose-Response Relationship, Drug; D016228:Endothelial Growth Factors / Q000096:biosynthesis / Q000235:genetics*; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000276:immunology; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000096:biosynthesis; D006801:Humans; D007150:Immunohistochemistry; D008222:Lymphokines / Q000096:biosynthesis / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000628:therapy*; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D013873:Thionucleotides / Q000494:pharmacology*; D016211:Transforming Growth Factor alpha / Q000096:biosynthesis; D014407:Tumor Cells, Cultured; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D023041:Xenograft Model Antitumor Assays
D000911:Antibodies, Monoclonal; D016228:Endothelial Growth Factors; D008222:Lymphokines; D016376:Oligonucleotides, Antisense; D013873:Thionucleotides; D016211:Transforming Growth Factor alpha; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D016222:Fibroblast Growth Factor 2; D066246:ErbB Receptors