Tumor-induced angiogenesis. Lack of inhibition by irradiation.

The effect of irradiation of tumors on their ability to induce vascular responses (angiogenesis) was studied. Rat Walker carcino-sarcoma 256, rabbit V2 carcinoma, mouse (C57Bl) melanoma and mouse (129) teratoma (OTT 6050, 100K) were irradiated with up to 5000R, then grafted either to the chicken chorioallantoic membrane or intracorneally into adult rabbits to assess competence to provoke angiogenesis. For all tumors and both assay systems the results were similar: irradiation did not interfere with tumor-induced vascular responses.