Ganglioside changes induced by tumor promoters in promotable JB6 mouse epidermal cells: antagonism by an antipromoter.

Since cell surface gangliosides have been implicated in the regulation of cell growth and differentiation and since tumor-promoting phorbol esters produce a number of membrane changes, the possibility was investigated that ganglioside changes may play a role in promotion of transformation in JB6 mouse epidermal cells. The studies showed that tumor-promoting but not non-promoting phorbol esters produced decreased precursor incorporation into disialoganglioside GD1b and an unknown ganglioside, Gx. These ganglioside responses to promoters were antagonized by the antipromoter retinoic acid, thus suggesting that alterations in ganglioside levels may be involved in promotion of transformation.