Control of differentiation of a mammary cell line by lipids.

Abstract

A rat mammary neoplastic cell line (LA7) undergoes spontaneous differentiation into domes due to production of specific inducers by the cells. Some of these inducers may be lipids. Lipids regulate this differentiation as inducers and inhibitors. One inhibitor is the tumor promoter tetradecanoyl-13 phorbol 12-acetate. The inducers are saturated fatty acids of 2 groups: butyric acid and acids with chain lengths from C13 to C16, especially myristic acid (C14). Other inducers are myristoyl and palmitoyl lysolecithins, myristic acid methyl ester and 2 cationic detergents with a tetradecenyl chain. The lipids with a C14-C16 alkyl chain may affect differentiation by recognizing specific receptors through their alkyl chains, the effects obtained depending on the head groups. These lipids may be physiological regulators in the mammary gland.