Effect of hyperthemia in combination with vitamin E and cyclic amp on neuroblastoma cells in culture

Abstract

The effect of heat in combination with DL-alpha-tocopheryl (vitamin E) succinate and adenosine 3′, 5′-cyclic monophosphate (cAMP) stimulating agents on mouse neuroblastoma cells (NBP 2) in culture on the criterion of growth inhibition (due to cell death and inhibition of cell division) was studied. Heat (41°−40°) alone inhibited growth; however, the extent of growth inhibition was dependent upon the temperature and the time of heat treatment. Heat (41°−40°) in combination with vitamin E succinate (5 μg/ml) produced an additive effect on the criterion of growth inhibition. Vitamin C (100 μg/ml) failed to modify the effect of heat. Prostaglandin A 2, a stimulator of adenylate cyclase, and 4 - (3-butoxy-4-methoxybenzyl)-2-imidazolindinone (R020-1724), an inhibitor of cyclic nucleotide phosphodiesterase, are known to induce irreversible differentiation in mouse neuroblastoma cells in culture. These agents, in combination with heat (40°) produced a synergistic effect on the criterion of growth inhibition. These data suggest that the addition of vitamin E and cAMP stimulating agents may increase the effectiveness of hyperthermia protocol.