CYTOTOXICITY OF ETHER PHOSPHOLIPID BM-41.440 ON NEUROBLASTOMA-CELLS

The thioether lysophospholipid BM 41.440 proved to be toxic against ce lls of two neuroblastoma cell lines in a dose- and time-dependent mann er. The ID50 estimated in three different in vitro test systems declin ed from about 10 mu g/ml after 24 h to 1 mu g/ml after a 1-week treatm ent of the neuroblastoma cells. These values are comparable to the ID5 0 found for neoplastic cells derived from other tissues. In comparison , hematopoietic progenitor cells (granulocyte/monocyte-colony-forming units) proved to be less sensitive to shortterm treatment with BM 41.4 40. After long exposure to this drug the selectivity towards neuroblas toma cells decreased. This observation makes it unlikely that BM 41.44 0 can be used for treatment of neoplasia such as neuroblastoma, becaus e only short-term treatment is acceptable considering the high bone ma rrow toxicity.