Inhibition of Human Rhabdomyosarcoma-Cell Growth in Agar by Dibutyryl Cyclic AMP2

Abstract

Dibutyryl cyclic AMP (dbcAMP) restores several “normal” characteristics to transformed cells in vitro. The ability of human rhabdomyosarcoma (RD) cells to form colonies in semisolid agar, a characteristic of transformed cells, was inhibited by 1 mM dbcAMP. dbcAMP also suppressed the growth of RD cells in monolayer culture and caused a marked morphologic change. The growth inhibition of monolayer cell cultures was reversible and was decreased when the cells were grown in control medium for 6 days before treatment.