The effect of cyclic AMP on the growth and morphology of a normal human fibroblast parent strain and its transformed progeny line.

A normal human diploid fibroblast cell strain, Lederle 130 (Led 130), and its virus-transformed progeny line, transformed Led 130, were subjected to 0.75 and 1.5 mM concentrations of adenosine-5'-monophosphate (AMP), cyclic AMP (cAMP) and dibutyryl cyclic AMP (Bt2cAMP). While cAMP was markedly inhibitory to neoplastic cells at 1.5 mM, Bt2-cAMP was even more effective at this concentration, producing 85% inhibition by 4 days and 91% inhibition by 6 days. Bt2-cAMP was the only nucleotide to reverse morphological transformation effects in the neoplastic fibroblasts. Normal fibroblasts were inhibited in growth rate to a comparable extent by all nucleotides, and were not altered morphologically.