体外研究
At a concentration of 1.0 μg/mL, hepsulfam is active in eight of 37 tumors (22%) in the clonogenic assay. Hepsulfam demonstrates a clear in vitro toxicity to human bone marrow cells (CFU-GM) from healthy donors. Evaluation of equitoxic concentrations in vitro reveals a higher activity of hepsulfam, especially in non-small cell lung cancer. Hepsulfam is more toxic to L1210 leukemia cells than is busulfan, its structural homologue . Consistent with the difference in toxicity, hepsulfam induces DNA interstrand cross-links in L1210 mouse leukemia cells, whereas busulfan does not. Hepsulfam is more cytotoxic to two human leukemia cell lines (111-60 and K562) and to two human colon carcinoma cell lines (BE and HT-29) than is busulfan. As in 11210 cells, hepsulfam induces a higher level of DNA interstrand cross-links than busulfan. Hepsulfam is also more cytotoxic to the human leukemia cell lines when the concentrations are reduced 10-fold and the duration of drug exposure is increased to 12 h.