Combination of interleukin-2 and irradiation in therapy of murine tumors.
Experiments were designed to investigate the therapeutic efficacy of interleukin-2 (IL-2) combined with radiotherapy. The effect of IL-2 and local thoracic irradiation (LTI) was determined on 4-day-old lung micrometastases, generated by i.v. injection of tumor cells into mice. IL-2 alone reduced the number of lung nodules more effectively when given from 1 to 4 than 4 to 7 days after tumor cell injection. The combination of IL-2 and LTI reduced the number of lung nodules more than did the individual treatments alone. When IL-2 therapy was combined with local irradiation of 8-mm leg tumors, there was no change in the TCD50 (radiation dose yielding 50% local tumor control). However, the combination of IL-2 treatment on days 1-4 with irradiation of tumor-bearing legs on day 1 after inoculation of tumor cells reduced the TCD50 by a factor of 1.3. These results show that IL-2 improves tumor radiotherapy, but that the improvement depends on anatomic localization and tumor size at the time of treatment.
Hunter
N
N
Department of Experimental Radiotherapy, University of Texas M. D. Anderson Cancer Center, Houston 77030.
Nakayama
T
T
Ito
H
H
Woo
S
S
Milas
L
L
D000818:Animals; D003131:Combined Modality Therapy; D005121:Extremities; D005260:Female; D005354:Fibrosarcoma / Q000532:radiotherapy / Q000556:secondary* / Q000628:therapy*; D007376:Interleukin-2 / Q000627:therapeutic use*; D008175:Lung Neoplasms / Q000532:radiotherapy / Q000556:secondary* / Q000628:therapy*; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D014183:Transplantation, Heterologous
D007376:Interleukin-2