Enhancement of the antitumor effect of gamma-ray irradiation in combination with camptothecin against human colorectal adenocarcinoma.
The effect of gamma-ray irradiation and camptothecin (CAM) on human colorectal adenocarcinoma (LS 174T) growth was examined. On inhibition of DNA synthesis of LS 174T cells, almost all combined treatments presented a synergistic effect, excepting that the additive effects were shown at the lowest or the highest doses of CAM prior to the gamma-ray (137Cs) irradiation. The in vivo antitumor activity of 131I-NCC-CO-411 monoclonal antibody against carcinoembryonic antigen in combination with CAM was assessed by a tumor growth rate in LS 174T tumor-bearing nude mice. The tumor growth of the combined group was supra-additively suppressed in comparison with that of the individual group. The results suggest that the efficacy of radioimmunotherapy may be enhanced by combination treatment with CAM. A clinical protocol involving a combination treatment with CAM is underway.
Wang
D S
DS
Research Institute for Biosciences, Science University of Tokyo, Chiba, Japan.
Ueno
Y
Y
Oyamada
H
H
Kojima
S
S
D000230:Adenocarcinoma / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D000972:Antineoplastic Agents, Phytogenic / Q000627:therapeutic use*; D002166:Camptothecin / Q000627:therapeutic use*; D002272:Carcinoembryonic Antigen / Q000276:immunology; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy*; D003131:Combined Modality Therapy; D005720:Gamma Rays; D006801:Humans; D007457:Iodine Radioisotopes; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D016499:Radioimmunotherapy; D014183:Transplantation, Heterologous
D000911:Antibodies, Monoclonal; D000972:Antineoplastic Agents, Phytogenic; D002272:Carcinoembryonic Antigen; D007457:Iodine Radioisotopes; D002166:Camptothecin