J Korean Soc Ther Radiol Oncol.  2004 Jun;22(2):138-144.

Trichostatin A, a Histone Deacetylase Inhibitor, Potentiated Cytotoxic Effect of Ionizing Radiation in Human Head and Neck Cancer Cell Lines

• Kim JH
• Shin JH
• Chie EK
• Wu HG
• Kim JS
• Kim IH
• Ha SW
• Park CI
• Kang WS

Abstract

PURPOSE: We have previously reported that human glioblastoma cells are sensitized to radiation-induced death after their exposure to trichostatin A (TSA), a histone deacetylase inhibitor (HDAC-I), prior to the irradiation. We aimed to measure the magnitude of the radiosensitizing effect of TSA in human head and neck cancer cell lines. MATERIALS AND MEHTODS: Human head and neck cancer cell lines, HN-3 and HN-9, were exposed to 0, 50, 100, and 200 nM TSA for 18 hr prior to irradiation. Then, the TSA-treated cells were irradiated with 0, 2, 4, 6, and 8 Gy, and cell survival was measured by clonogenic assay.
RESULTS
Pre-irradiation exposure to TSA was found to radiosensitize HN-3 and HN-9 cell lines. In HN-9 cells, the fraction surviving after 2 Gy (SF2) was significantly reduced by treatment of TSA at concentration as low as 50 nM. However, a treatment with 200 nM TSA was required to significantly decrease SF2 in the HN-3 cell line. SER of pre-irradiation treatment with 200 nM TSA was 1.84 in HN-3 and 7.24 in HN-9, respectively.
CONCLUSIONS
Our results clearly showed that human head and neck cancer cell lines can be sensitized to ionizing radiation by pre-irradiation inhibition of histone deacetylase (HDAC) using TSA, and that this potentiation might well be a general phenomenon.

Keyword

Trichostatin A; Histone deacetylase inhibitor; Radiosensitization; Head and neck cancer

MeSH Terms

Cell Line*
Cell Survival
Glioblastoma
Head and Neck Neoplasms*
Head*
Histone Deacetylase Inhibitors*
Histone Deacetylases*
Histones*
Humans*
Radiation, Ionizing*
Radiation-Sensitizing Agents
Histone Deacetylase Inhibitors
Histone Deacetylases
Histones
Radiation-Sensitizing Agents