TY - JOUR
T1 - Chemosensitization of oral squamous cell carcinoma cells to cisplatin by histone deacetylase inhibitor, suberoylanilide hydroxamic acid
AU - Rikiishi, Hidemi
AU - Shinohara, Fumiaki
AU - Sato, Tomonori
AU - Sato, Yoshitaro
AU - Suzuki, Maiko
AU - Echigo, Seishi
PY - 2007/5
Y1 - 2007/5
N2 - In the present study, the precise mechanism of the enhancing action of histone deacetylase (HDAC) inhibitors on cisplatin (CDDP)-induced apoptosis was investigated using suberoylanilide hydroxamic acid (SAHA) in human oral squamous cell carcinoma cells (HSC-3). HDAC inhibitors are promising novel compounds for the treatment of cancer, which cooperate with chemotherapeutic agents to induce apoptosis. Apoptosis enhancement of HSC-3 cells by SAHA was accompanied by the activation of caspase-3, -8 and -9, suggesting a mitochondrial-dependent amplification loop. Concomitant treatment (CDDP/SAHA) of cells resulted in the most effective enhancement of apoptosis compared to other timing combinations. By means of cell-cycle synchronization, G0/G1-phase cells proved to be a more sensitive fraction to SAHA action than their synchronized counterparts in other phases. Furthermore, cells treated with SAHA revealed a decrease in intracellular reduced glutathione (GSH) contents. Of importance, the GSH synthesis inhibitor, diethyl maleate, decreased intracellular GSH and enhanced CDDP-induced apoptosis in a similar pattern of timing to SAHA. Thus, SAHA appears to disrupt the intracellular redox balance, which causes maximal apoptosis at the G0/G1 phase arrested by CDDP in HSC-3 cells. These results demonstrate that HDAC inhibitors not only cause a change in the histone acetylation status, but are also able to influence the apoptotic process at several levels, and GSH plays a key role in governing SAHA-dependent enhancement of CDDP-induced apoptosis.
AB - In the present study, the precise mechanism of the enhancing action of histone deacetylase (HDAC) inhibitors on cisplatin (CDDP)-induced apoptosis was investigated using suberoylanilide hydroxamic acid (SAHA) in human oral squamous cell carcinoma cells (HSC-3). HDAC inhibitors are promising novel compounds for the treatment of cancer, which cooperate with chemotherapeutic agents to induce apoptosis. Apoptosis enhancement of HSC-3 cells by SAHA was accompanied by the activation of caspase-3, -8 and -9, suggesting a mitochondrial-dependent amplification loop. Concomitant treatment (CDDP/SAHA) of cells resulted in the most effective enhancement of apoptosis compared to other timing combinations. By means of cell-cycle synchronization, G0/G1-phase cells proved to be a more sensitive fraction to SAHA action than their synchronized counterparts in other phases. Furthermore, cells treated with SAHA revealed a decrease in intracellular reduced glutathione (GSH) contents. Of importance, the GSH synthesis inhibitor, diethyl maleate, decreased intracellular GSH and enhanced CDDP-induced apoptosis in a similar pattern of timing to SAHA. Thus, SAHA appears to disrupt the intracellular redox balance, which causes maximal apoptosis at the G0/G1 phase arrested by CDDP in HSC-3 cells. These results demonstrate that HDAC inhibitors not only cause a change in the histone acetylation status, but are also able to influence the apoptotic process at several levels, and GSH plays a key role in governing SAHA-dependent enhancement of CDDP-induced apoptosis.
KW - Apoptosis
KW - Cell-cycle
KW - Cisplatin
KW - Glutathione
KW - Oral squamous cell carcinoma
KW - Suberoylanilide hydroxamic acid
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U2 - 10.3892/ijo.30.5.1181
DO - 10.3892/ijo.30.5.1181
M3 - Article
C2 - 17390020
AN - SCOPUS:34447315913
SN - 1019-6439
VL - 30
SP - 1181
EP - 1188
JO - International journal of oncology
JF - International journal of oncology
IS - 5
ER -