INFLUENCE OF THE ANTITUMORAL HEXADECYLPHOSPHOCHOLINE UPON GLYCEROLIPID METABOLISM IN HepG2 CELLS

Abstract
Alkylphosphocholines, derived from naturally occurring phospholipids, are a new class of antineoplastic agents which exerts their cytostatic effect by interacting with lipid membranes and membrane-dependent processes. One of the most characterized compounds in this group is hexadecylphosphocholine (HePC), which exerts antitumoral activity against a broad spectrum of established tumour cell lines. It is currently used for the topical palliative treatment of cutaneous metastases of mammary carcinomas. In our laboratory, we have recently reported that HePC interferes with phosphatidylcholine synthesis via both CDP-choline and phosphatidylethanolamine methylation in HepG2 human hepatoma cell line, frequently used as a model for studies of hepatic lipid metabolism. Interestingly, HePC also interferes with sphingolipid metabolism by reducing the formation of sphingomyelin. This reduction is accompanied by a substantial increase in the production of ceramides. All these metabolic alterations could be associated with morphological changes in the cell, which can induce the apoptotic process. These results confirm the potential of HePC as antineoplastic agent.

Key words
Hexadecylphosphocholine, phosphatidylcholine synthesis, apoptotic, HepG2 cells

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