Manipulation of cholesterol metabolism open several possibilities of i
nterfering with the growth of malignant cells. Deprivation of choleste
rol decreases the velocity of growth and alters the composition of the
cell membrane. The high requirement for LDL of malignant cells can be
utilized for drug targeting Proliferation assays were performed with
neuroblastoma cells and cell lines of acute myeloid leukemia deprived
of cholesterol by inhibition of HMG-CoA-reductase or culture in LDL-de
ficient medium. The cholesterol content of the cell membrane when I ed
uced to 50 % had no effect on the toxicity of LAK-cells but the toxici
ty of the fluorescent dye merocyanine MC 540 was enhanced two-fold. LD
L-mediated drug targeting to AML cells was performed with oxidized LDL
and showed toxic reactions. These results proved that cholesterol dep
rivation could be used to support some therapeutic approaches.