Brief Communication: Effect of Dibutyryl Cyclic Adenosine 3′,S′-Monophosphate on In Vivo Growth of Walker 256 Carcinoma: Isolation of Responsive and Unresponsive Cell Populations

Abstract

N⁶,O²′-dibutyryl cyclic adenosine 3′ ,5′-monophosphate (DBcAMP) arrested growth of Walker 256 in vivo. Further treatment induced regression in some tumors, whereas others regrew as untreated controls. Selective transplantation of either rapidly growing or rapidly regressing tumors under DBcAMP treatment separated 2 cell populations, DBcAMP-responsive and DBcAMP-unresponsive. None of the regressed tumors had resumed growth by 6 months after treatment.