Cytotoxic activity of the thioether phospholipid analogue BM 41.440 in primary human tumor cultures.

The inhibitory effect of the new thioether alkyl lysophospholipid analogue 1-hexadecylmercapto-2-methoxy-methyl-rac-glycero-3-phosphocholine (BM 41.440, Ilmofosine) on colony formation of different spontaneous human tumors was studied in vitro using a methyl cellulose monolayer assay. The most sensitive tumors were lung (small cell, squamous cell and adenocarcinomas), gastrointestinal and ovarian cancers and hyernephromas. On the basis of the current definition of sensitivity by the National Cancer Institute, Bethesda, MD, i.e. more than 70% inhibition of colony formation at an arbitrary concentration of 10 micrograms/ml, 34 out of 64 malignancies tested were susceptible to BM 41.440.