Effect of vitamin E succinate and a cAMP-stimulating agent on the expression of c-myc and N-myc and H-ras in murine neuroblastoma cells.

D-Alpha-tocopheryl succinate (vitamin E succinate) at a concentration of 11.3 microM inhibited growth and reduced the expression of c-myc, N-myc and H-ras specific mRNAs in murine neuroblastoma cells (NBP2) in culture. R020-1724 [4-(3-butoxy-4-methoxybenzyl)-2- imidazolidinone], an inhibitor of cyclic AMP phosphodiesterase, also inhibited growth and reduced the expression of these oncogenes. Vitamin E succinate treatment caused the formation of two c-myc related transcript of 1.9 and 3.7 kb; however, R020-1724 treatment did not. These results suggest that the inhibition of growth is sufficient to reduce the expression of c-myc, N-myc and H-ras in NB cells in culture, but it is not sufficient to produce two c-myc related transcripts.