Induction of G₂/M phase arrest and apoptosis by potent antitumor APCA in human cervix carcinoma cells

3-(dimethylamino-ethylamino)-8-oxo-8H-acenaphthol[1, 2-b]pyrrole-9- carboxylic acid (APCA), as a potent antitumor compound, showed anticancer activity on a series of established cancer cells. Meanwhile, the cytotoxic effects of APCA were much smaller on normal human cells than that on cancer cells. This study investigated the molecular mechanisms underlying APCA-induced growth inhibition in HeLa cells. The results showed that the APCA-induced cell cycle arrest at G₂/M phase correlated with cyclinB1 and cyclin-dependent kinase 1 expression downregulation in a p53-independent manner, and also caused an increase in apoptosis, which was confirmed by characteristic morphological changes and increased apoptotic sub-G1 population. Furthermore, translocation inhibition of nuclear factor-κB, upregulation of Bax, and downregulation of Bcl-2, caspase-3 and caspase-9 activation, and poly-(ADP-ribose) polymerase cleavage were observed in HeLa cells treated with APCA, which indicated that the mitochondrial pathway was involved in the apoptosis signal pathway. In summary, APCA displayed an antitumor effect through cell cycle arrest and apoptotic induction in HeLa cells, which suggested that APCA might have therapeutic potential against cervix carcinoma as an effective lead compound.