Radiosensitization of the RIF-1 murine flank tumor by desmethylmisonidazole (Ro 05 9963) during interstitial brachytherapy.
We have investigated the interaction of the nitroimidazole radiosensitizer desmethylmisonidazole (Ro 05 9963) with interstitial radiation using a clonogenic cell assay as the endpoint. Removable I-125 sources were implanted at right angles to the outer surface of globular RIF-1 tumors grown in the flanks of C3H/He mice. Desmethylmisonidazole was administered by continuous intraperitoneal infusion at a rate of 2.7 mg/gm body weight /24 hr. Tumor and serum drug levels were measured by high performance liquid chromatography. Tumor drug levels of 40--100 mugm/gm tumor tissue were achieved consistently. No appreciable cytotoxicity was produced by desmethylmisonidazole alone, but a radiosensitization effect with a dose modifying factor of 1.6 was found.
D000818:Animals; D001918:Brachytherapy; D002470:Cell Survival / Q000187:drug effects; D003114:Colony-Forming Units Assay; D005260:Female; D051379:Mice; D008920:Misonidazole / Q000031:analogs & derivatives / Q000494:pharmacology*; D009374:Neoplasms, Experimental / Q000532:radiotherapy*; D009593:Nitroimidazoles / Q000494:pharmacology*; D011838:Radiation-Sensitizing Agents; D011879:Radiotherapy Dosage
D009593:Nitroimidazoles; D011838:Radiation-Sensitizing Agents; D008920:Misonidazole; C009997:desmethylmisonidazole