Neuroblastoma clones: prostaglandin versus dibutyryl cyclic AMP, 8-benzylthio-cyclic AMP, phosphodiesterase inhibitors and x-rays

The effects of prostaglandin (PG)E1, dibutyryl cyclic AMP, 8-benzyl-thio-cyclic AMP, inhibitors of phosphodiesterase [papaverine and 4-(3-butoxy-4-methoxybenzyl)2-imidazolidinone], and X-irradiation on two neuroblastoma clones, NBA2(1) and NBDB- were studied. In the NBDB-clone PGE1 was much more effective in causing morphological differentiation than any other differentiating agents. In the NBA2(1) clone PGE1 was as effective as the other agents. Adenylate cyclase of both clones may be sensitive to PGE1. The phosphodiesterase level in clone NBA2(1) is probably inhibited by other differentiating agents but this enzyme level in clone NBDB- either is too low to be of any significance or is insensitive to phosphodiesterase inhibitors. In clone NBDB- the biological property of the cell may be more important in initiating the morphological differentiation than the interaction between the cell and the surface of the culture dish.