Sodium valproate enhances doxorubicin cytotoxicity in breast cancer cells in vitro / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of sodium valproate, a histone deacetylase inhibitor, on the cytotoxicity of doxorubicin in breast cancer cells.</p><p><b>METHODS</b>Western blotting was used to assess Cx43 protein expression in breast cancer Hs578T cells exposed to doxorubicin and sodium valproate. MTT assay was used to determine the cytotoxicity of doxorubicin; annexin V/PI double staining and Hochest 33258 fluorescence staining were employed to detect doxorubicin-induced early and late apoptosis, respectively.</p><p><b>RESULTS</b>Western blotting showed that sodium valproate significantly increased Cx43 protein expression in Hs578T cells (P/0.01). The cells exposed to both sodium valproate and doxorubicin showed significantly lowered cell viability compared with the cells exposed to doxorubicin alone (P/0.01). Exposure to both sodium valproate and doxorubicin resulted in significantly increased early and late cell apoptosis rate compared with doxorubicin treatment alone (P/0.01).</p><p><b>CONCLUSION</b>sodium valproate can significantly enhance the cytotoxicity of doxorubicin and increase doxorubicin-induced apoptosis in breast cancer cells in vitro possibly by enhancing the gap junction function.</p>