Enhancement of Sodium Butyrate-induced Cell Death by Hyperthermia in HCT 116 Human Colorectal Cancer Cells

Abstract

Aim: The possible enhancing effect of the combined use of sodium butyrate (SB) and hyperthermia to kill HCT 116 cells was evaluated. Materials and Methods: HCT 116 cells were subjected to SB (1 mM) treatment followed by hyperthermia (44°C 60 min) and the effects on cell death, cell proliferation and the cell cycle were examined. Apoptosis-indicating protein expressions and intracellular superoxide formation were also analysed. Results: A marked reduction in the growth rate of the combined-treatment group was observed compared to those of the single-treatment groups. This involved the increased expression of p53 and p21, the alteration of the balance of anti- and proapoptotic Bcl-2 family proteins and enhanced superoxide formation. However, the death receptor pathway played no role. Conclusion: Hyperthermia synergistically promoted cell death induced by SB. Thus, the combined treatment led to mutual potentiation of the killing effects of each agent.