Nature of 3,6-Bis{5-chloro-2-piperidinyl)-2,5-piperazinedione-Induced Cytotoxicity in Chinese Hamster Ovary Cells

Abstract

We studied the effect of 3,6-bis(5-chloro-2-piperidinyl)-2,5-piperazinedione (BCP) on various parameters of the replication cycle and cell growth on monolayer cultures of Chinese hamster ovary cells. The results indicated that BCP had no effect on the G₁-S transition or the passage of cells from metaphase to G₁. However, BCP prolonged S- and G₂-phases because of its retarding effect on DNA synthesis. BCP was more toxic to Sphase cells than to G₁ or mitotic cells. As with other alkylating agents, chromosome damage due to BCP could be seen only in cells that had undergone DNA replication after exposure to the drug.