title: BLEDTA: tumor localization by a bleomycin analogue containing a metal-chelating group.
abstract: Two different Co(III) complexes of the antitumor antibiotic bleomycin have been prepared, and their in vivo distribution in mice has been investigated. The more thermodynamically stable of the Co(III)-bleomycin complexes has been modified by reaction with the bifunctional chelating agent 1-(p-bromoacetamidophenyl)ethylenedinitrilotetraacetic acid, to give a bleomycin derivative (BLEDTA) containing a powerful metal-chelating group. BLEDTA was radiolabeled with 111In(III) and its in vivo distribution in mice was examined. The potential of 111In-labeled BLEDTA as a tumor-visualizing agent was also investigated in humans with biopsy-proven cancers, predominantly (70%) squamous carcinoma of the head and neck. All of the 29 patients studied had at least one clinically proven site of the disease visualized with 111In-BLEDTA. These clinical results are significantly better than results we obtained in a comparable group of patients using directly labeled 111In-bleomycin and are similar to those reported by Nouel for 57Co-bleomycin [GANN Monogr. Cancer Res., 19, 301 (1976)].
mesh_terms: D000328:Adult; D000818:Animals; D001761:Bleomycin / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging; D002614:Chelating Agents; D003037:Cobalt Radioisotopes; D004492:Edetic Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009369:Neoplasms / Q000000981:diagnostic imaging*; D009374:Neoplasms, Experimental / Q000000981:diagnostic imaging; D011877:Radionuclide Imaging; D014018:Tissue Distribution
chemical_list: D002614:Chelating Agents; D003037:Cobalt Radioisotopes; D001761:Bleomycin; D004492:Edetic Acid