• mouse embryonic fibroblasts and neurospheres are more sensitive to camptothecin than wild-type cells
• mice treated with camptothecin-11 or topotecan exhibit weakness and diarrhea within 2 days of completion of administration unlike wild-type mice
• following treatment with camptothecin-11 or topotecan, mice exhibit extensive necrosis of the slowly proliferating intestinal, renal and hepatic tissues, and extensive apoptosis and loss of rapidly proliferating lymphoid and hematopoietic tissues compared to in similarly treated wild-type mice
• following treatment with camptothecin-11 or topotecan, mice exhibit electrophysiological changes, prolonged distal latencies and reduced compound muscle action potentials compared to in similarly treated wild-type mice
• mice and embryonic fibroblasts are hypersensitive to bleomycin but not etoposide
• however, mice treated with camptothecin-11 or topotecan fail to exhibit ataxia or neuropathy as in SCAN1 patients and non-proliferating neural cells are resistant to acute toxicity of Topo I DNA complexes