Simultaneous application of the vascular endothelial growth factor (VEGF) receptor inhibitor PTK787/ZK 222584 and ionizing radiation does not further reduce the growth of canine oral melanoma xenografts in nude mice.
PTK787/ZK 222584 is an inhibitor of the vascular endothelial growth factor (VEGF) receptor tyrosine kinases. In this study, the effectiveness of PTK787/ZK 222584 and radiation on canine oral melanoma xenografts was assessed. Xenografts were treated with radiotherapy (4x6Gy), or with PTK787/ZK 222584, or with a combination of both. Treatment efficacy was assessed using a tumour growth delay assay, serial power Doppler and pO(2) measurements during and after therapy. There was a significant growth delay for the group treated with radiation alone and for the combined treatment group. However, tumour growth delay was similar in both groups. Tumours were hypoxic before irradiation and no significant re-oxygenation occurred during therapy. In all tumours, vascularity and perfusion were significantly lower at the end of the study but no significant differences in perfusion, vascularity and oxygenation status were observed between and within treatment groups. The combination of PTK787/ZK 222584 and radiotherapy did not perform better than radiotherapy alone in this model.
Inteeworn
Natalie
N
Section of Diagnostic Imaging and Radio-Oncology, Vetsuisse Faculty, University of Zürich, Switzerland. inteewor@vt.edu
Ohlerth
Stefanie
S
Höpfl
Gisele
G
Guscetti
Franco
F
Bley
Carla Rohrer
CR
Wergin
Melanie C
MC
Roos
Malgorzata
M
Gassmann
Max
M
Kaser-Hotz
Barbara
B
D000818:Animals; D003131:Combined Modality Therapy; D004285:Dogs; D004791:Enzyme Inhibitors / Q000627:therapeutic use*; D005260:Female; D008545:Melanoma / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000532:radiotherapy / Q000662:veterinary*; D051379:Mice; D008819:Mice, Nude; D009062:Mouth Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000532:radiotherapy / Q000662:veterinary*; D018714:Radiotherapy, Adjuvant; D051381:Rats; D040262:Receptors, Vascular Endothelial Growth Factor / Q000037:antagonists & inhibitors*; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler / Q000379:methods / Q000662:veterinary; D042442:Vascular Endothelial Growth Factors / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays / Q000662:veterinary
D004791:Enzyme Inhibitors; D042442:Vascular Endothelial Growth Factors; D040262:Receptors, Vascular Endothelial Growth Factor