Comparison of radiolabeled bleomycins and gallium citrate in tumor-bearing mice.
Radioiodinated bleomycin is a chemically stable radiopharmaceutical that can be prepared with high specific activity using 123I. Its pharmacokinetics were compared with those of 99mTc,- 111In-, and 57Co-bleomycin, and 67Ga citrate in mice bearing a transplanted KHJJ tumor. The in vivo kinetics and stability of 123I- and 57Co-bleomycin were similar: both were acceptable, although not equivalent, tags for bleomycin and, along with 67Ga citrate, both had biologic properties suitable for tumor detection. Both 99mTc- and 111In-bleomycin dissociated rapidly in vivo and hence do not represent legitimate tags for bleomycin. However, 111In-bleomycin may have tumor-localizing properties related to its biochemical properties after the indium and chelate separate in vivo. Iodine-123 is superior to either 57Co or 55Co. Tumor-to-blood and tumor-to-liver ratios were higher for I-bleomycin than for 67Ga or Co-bleomycin. The nearly ideal nuclear properties of 123I should complement the biologic properties of bleomycin and lead to a useful tumor radiodiagnostic agent.
D000230:Adenocarcinoma / Q000175:diagnosis; D000818:Animals; D001761:Bleomycin / Q000378:metabolism; D002460:Cell Line; D003037:Cobalt Radioisotopes / Q000378:metabolism; D005710:Gallium Radioisotopes / Q000378:metabolism; D007204:Indium / Q000378:metabolism; D007457:Iodine Radioisotopes / Q000378:metabolism; D007553:Isotope Labeling; D007700:Kinetics; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000175:diagnosis*; D011868:Radioisotopes / Q000378:metabolism; D013667:Technetium / Q000378:metabolism; D014184:Transplantation, Homologous
D003037:Cobalt Radioisotopes; D005710:Gallium Radioisotopes; D007457:Iodine Radioisotopes; D011868:Radioisotopes; D007204:Indium; D001761:Bleomycin; D013667:Technetium