Cell growth, ganglioside effect

Bremer EG, Schlessinger J, Hakomori S Ganglioside-mediated modulation of cell growth Specific effects of GM3 on tyrosine phosphorylation of the epidermal growth factor receptor. J. Biol. Chem. 1986 261 2434-2440. 

Butyrate appears to have its most profound effects on neoplastic cells such as HeLa in addition to morphological and biochemical differentiation, the fatty acid inhibits cell growth (2). Previous studies have established a correlation between decreased ganglioside synthesis and malignant transformation (43-46). Transformed baby hamster kidney and newborn rat kidney cells exhibited a loss of GM3 and sialyl transferase activity (43,44). 

We have shown that the inhibitory effect of GM3 on EGF receptor Tyr kinase of A431 cells is greatly enhanced in the presence of lyso-phosphatidylcho-line (lyso-PC), but not lyso-phosphatidylethanolamine, lyso-phosphatidylserine, or lyso-phosphatidylinositol (Igarashi et ai, 1990). In an in vitro assay system, lyso-PC (but not the other compounds listed above) greatly stimulated EGF-dependent Tyr phosphorylation of EGF receptor. It is therefore assumed that lyso-PC promotes the inhibitory effect of GM3 in modulation of EGF receptor kinase (RK). Figure 1 illustrates the possible cooperative effect between lyso-PC and GM3, and specificities of ganglioside effects on various growth factor and hormone receptors. 

Song, W., Vacca, M. F., Welti, R., and Rintoul, D. A., 1991, Effects of gangliosides and de-N-acetyl G 3 on epidermal growth factor receptor kinase activity and cell growth, J. Biol. Chem. 266 10174-10181. 

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