Characterization of cellular lipids in doxorubicin-sensitive and -resistant P388 mouse leukemia cells.

The purpose of this study was to determine whether changes in cellular lipid composition accompanied the selection of cells that are resistant to the anthracycline doxorubicin. Total cellular lipid extracts from doxorubicin-sensitive and doxorubicin-resistant P388 murine leukemia cells were prepared and separated into neutral glycosphingolipids, gangliosides, phospholipids, and neutral lipid families. No significant quantitative differences in total cholesterol, lipid-bound sialic acid, neutral hexose, and lipid-bound phosphate were found between the two cell lines. Gas-liquid chromatographic analysis of the fatty acids derived from each lipid class demonstrated that sensitive and resistant cells had essentially identical fatty acid compositions. Qualitative evaluation of the four lipid classes by high-performance thin-layer chromatography revealed only minor differences in lipid composition between the resistant and the sensitive cells. Results from this study indicate that although minor differences between the two cell lines are present, no major cellular lipid differences are evident to account for the marked differences in the cellular pharmacokinetics and cytotoxic effects of doxorubicin between doxorubicin-sensitive and doxorubicin-resistant P388 murine leukemia a cells.