Killing of Human Lung Cancer Cells Using a New [111In]Bleomycin Complex [111In]BLMC

The ability of a ¹¹¹In]bleomycin complex (¹¹¹In]BLMC) to kill five cell lines of human lung cancer (small cell lung cancer) was investigated. Cells were exposed to either 0.9% NaC1, ¹¹¹In]C1₃, BLM, ¹¹¹In]BLMC, nonradioactive InC1₃, or In-BLMC for 60 minutes, plated in soft agarose, and assessed for colony formation. ¹¹¹In]BLMC (40-200 μ;C) carried by 15-25 μ;g BLM/ml) was more cytotoxic than BLM (15-25 μ;g BLM/ml) by a factor of 1.6-5.3 for five cell lines. The percent survival of N417 cells was 28.4 for ¹¹¹In]BLMC (40 μ;Ci/15 μ;g BLM/ml) and 54.3 for BLM (15 μ;g/ml); 1.9 for ¹¹¹In]BLMC (200 μ;Ci/25 μ;g BLM/ml), and 10.0 for BLM (25 μ;g/ml). ¹¹¹InC1₃ (200 μ;Ci/ml) and nonradioactive InC1₃ failed to inhibit colony formation. The new ¹¹¹In]BLMC may be useful for therapy of some lung cancer patients.