Uptake of low-density lipoprotein by malignant cells--possible therapeutic applications.

Cells acquire cholesterol via de novo synthesis and receptor-mediated uptake of low-density lipoprotein (LDL), the major cholesterol-carrying lipoprotein in blood. Human leukemic cells and certain tumor tissues display elevated receptor-mediated uptake of LDL as compared with the corresponding normal cells or tissues. LDL has therefore been proposed as a potential carrier for chemotherapeutic agents. Various methods have been employed to incorporate antineoplastic lipophilic drugs into LDL, and the resultant drug-LDL complexes have been shown to be cytotoxic toward tumor cells in vitro. Initial experiments with tumor-bearing animals suggest that LDL may be a promising carrier for drugs in the treatment of malignant diseases.