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PubMed · 3024721

Membrane ordering effects of the anticancer agent VM-26.

S E Wright·J C White
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Abstract

The effect of the anticancer agent VM-26 on acyl chain order of cellular and model membranes was examined by electron spin resonance techniques. The order parameter for the paramagnetic probe 5-doxyl stearate was increased when VM-26 was incorporated into the bilayer of fluid-phase dimyristoylphosphatidylcholine (DMPC) or gel-phase dipalmitoylphosphatidylcholine (DPPC) liposomes at concentrations up to 4.8 mol%. The ordering effect of VM-26 in DMPC was greater than that of cholesterol on an equimolar basis. The less cytotoxic congener of VM-26, VP-16, was only one-third as active as VM-26 in its ordering effects on DMPC. Higher order parameters for 5-doxyl stearate were also noted in asolectin liposomes, Ehrlich ascites tumor cells, and CCRF-CEM cells treated with VM-26. We conclude that VM-26 has significant membrane associated activity in addition to its previously recognized nuclear effects.

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1,2-DipalmitoylphosphatidylcholineAnimalsCarcinoma, Ehrlich TumorCell LineCell MembraneCholesterolCyclic N-OxidesDimyristoylphosphatidylcholineElectron Spin Resonance SpectroscopyEtoposideHumansLeukemiaLipid BilayersLiposomesMaleMembrane LipidsMicePodophyllotoxinSpin LabelsTeniposideComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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S E Wright, J C White. 1986-12-16. Membrane ordering effects of the anticancer agent VM-26.. https://doi.org/10.1016/0005-2736(86)90270-1

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