Alterations in mRNA expression of apoptosis-related genes BCL2, BAX, FAS, Caspase-3, and the novel member BCL2L12 after treatment of human leukemic cell line HL60 with the antineoplastic agent etoposide

Apoptotic cell death is a highly regulated process, which plays a crucial role in many biological events. Etoposide is an antineoplastic drug, which targets the DNA unwinding enzyme, topoisomerase II. The aim of the present research approach to investigate the expression of the apoptosis-related genes BCL2 (Bcl-2), FAS, Caspase-3, BAX and the new member BCL2L12, cloned by our group, along with treatment of HL-60 leukemia cells with etoposide. The kinetics of apoptosis induction and cell toxicity was evaluated by DNA laddering and MITT method, respectively. The mRNA expression levels of the genes were analyzed by RT PCR using gene-specific primers. beta-Actin was used as a control gene. An important downregulation of BCL2L12 was observed at 4 h of drug treatment, whereas BAX was upregulated at the same time point. No alteration in the expression pattern of the other apoptosis-related genes was detected. Since, the main anticarcinogenic effect of etoposide is due to the induction of apoptosis, these changes observed in the mRNA expression levels of the genes may be an underlying mechanism.