Effect of peplomycin or camptothecin-11 on X-ray skin injuries of ICR hairless mice.
In interdisciplinary oncotherapy by radiation and chemical substances, the injurious effects of radiation on the normal skin are occasionally modified by combined chemical substances. In the present experiment, the possible modifying effects of Peplomycin (PEP, 30 mg/kg body weight) and Camptothecin-11, an inhibitor of DNA topoisomerase I (CPT-11, 15 and 50 mg/kg body weight), on radiation skin injury were studied. Macroscopic changes on the thigh skin of male ICR hairless mice (at 8 weeks of age) induced by 10 Gy X-ray irradiation alone and the combined treatment with the anticancer substances were estimated by a modified scoring first reported by Lowy and Baker. Intraperitoneal administration of PEP significantly enhanced radiation skin injury; while CPT-11 (15 mg/kg), within the clinical dose range and in the similar molarities to that of PEP, did not show any appreciable modification effect. Treatment with CPT-11 (50 mg/kg) showed a radiation enhancement without significant difference. The chemotherapeutic radioenhancement ratios of the combined treatments of X-ray and PEP or CPT-11 (15 or 50 mg/kg) were 1.49, 1.17 or 1.34, respectively. Treatment with PEP at the accepted dose showed a radiation enhancement, while CPT-11 did not show any radiation enhancement within the clinical dose.
Kawahara
K
K
Department of Dermatology, Fukui Medical School, Japan.
Kano
E
E
Ueda
K
K
D000818:Animals; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D004264:DNA Topoisomerases, Type I / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D000077146:Irinotecan; D008297:Male; D051379:Mice; D008812:Mice, Hairless; D008813:Mice, Inbred ICR; D017663:Peplomycin / Q000008:administration & dosage / Q000494:pharmacology*; D011829:Radiation Dosage; D011833:Radiation Injuries, Experimental / Q000209:etiology* / Q000503:physiopathology; D011838:Radiation-Sensitizing Agents / Q000008:administration & dosage / Q000494:pharmacology; D012867:Skin / Q000187:drug effects* / Q000528:radiation effects*; D012871:Skin Diseases / Q000209:etiology* / Q000503:physiopathology; D013848:Thigh; D059004:Topoisomerase I Inhibitors; D014965:X-Rays
D011838:Radiation-Sensitizing Agents; D059004:Topoisomerase I Inhibitors; D017663:Peplomycin; D000077146:Irinotecan; D004264:DNA Topoisomerases, Type I; D002166:Camptothecin