[Potentiation of radiation-induced cell killing by histone deacetylase inhibitor]

HDAC inhibitor has been focused as a molecular target agent for cancer treatment because of unique pharmacological activity. HDAC inhibitors induce cancer cells to undergo growth arrest, differentiation or induce apoptosis in vitro, and also inhibit the growth of transplanted tumors in vivo, but the enhancement effect or interaction of HDAC inhibitors with other chemotherapeutic agents or radiation has not yet been fully investigated. Biade et al examined the effect of trichostatin A (TSA), and reported synergistic enhancement of radiosensitivity in human cancer cell lines. We also confirmed the similar results in vitro by using TSA in combination with radiation. The main purpose of this paper is to review the current status of HDAC inhibitor in clinical use, and evaluate the potential possibility for the potentiation of radiation-induced cell killing including the results of our research.