Effects of dibutyryl cyclic AMP and prostaglandin E 1 on cultured human glioma cells

Abstract Dibutyryl cyclic AMP (db-cAMP) and prostaglandin E 1 (PGE 1 ) induced morphological alterations in cultured human glioma cells (138 MG). Cells in serum-free medium, treated with db-cAMP (1 mM) or PGE 1 (10μg/ml), within 1–3 h showed multiple thin processes resembling those of normal glial cells. These processes increased in size during a 24 h incubation. In serum-containing medium the appearance of cells with multiple processes was delayed. The induced morphological alterations were reversible upon exchange with fresh serum-containing but not with serum-deprived medium. Actinomycin D (5 μg/ml) did not prevent the changes induced by PGE 1 or db-cAMP. Inhibition of protein synthesis with cycloheximide (10 μg/ml) did not arrest the initial (1–3 h) changes in morphology but blocked further growth of the processes on prolonged incubation. Vinblastine sulphate (0.1 μg/ml) completely inhibited the alterations induced by PGE 1 or db-cAMP.