Department of Physiology and Toxicology of Reproduction, Jagielonian University, Gronostajowa 9, PL 30-387 Kraków, Poland.
Pharmacol Rep. 2012;64(3):603-14. doi: 10.1016/s1734-1140(12)70856-3.
We have previously shown that due to its cytotoxic and cytostatic activities, valproic acid (VPA), but not levetiracetam (LEV), may have potential as a drug for treating human ovarian cancer. In the present study, we compare apoptotic mechanisms including gene and protein expression in the human ovarian cancer cell line, OVCAR-3, following exposure to VPA and LEV.
Cells were cultured with VPA or LEV at concentrations between 0.1 mM and 10 mM. Apoptosis was assessed by DNA fragmentation assay and expression of apoptosis-regulatory genes determined by real-time PCR and confirmed by western blotting. Time-dependent effects of VPA and LEV on activity of caspases (-3, -8 and -9) activity were evaluated by fluorescent assay and western blotting.
Exposure to VPA at concentrations above 5 mM resulted in an increase in DNA fragmentation, modulated expression of genes and proteins associated with apoptosis and activated caspases cascade. Exposure to LEV, however, did not affect DNA fragmentation and modulation of the mechanisms of apoptosis was not observed in LEV-treated cells at all doses used.
Exposure to high concentrations of VPA significantly stimulated apoptosis, by modulating the expression of genes and proteins responsible for cell death and also by activation of caspases cascade. Such effects were not observed with LEV. These data suggest that VPA should be seriously evaluated as an anti-cancer drug for ovarian cancer.
我们之前已经表明，由于其细胞毒性和细胞抑制活性，丙戊酸（VPA）而非左乙拉西坦（LEV）可能具有治疗人类卵巢癌的药物潜力。在本研究中，我们比较了 VPA 和 LEV 处理人卵巢癌细胞系 OVCAR-3 后的凋亡机制，包括基因和蛋白表达。
将细胞在浓度为 0.1mM 至 10mM 的 VPA 或 LEV 中培养。通过 DNA 片段化测定评估细胞凋亡，通过实时 PCR 确定凋亡调节基因的表达，并通过 Western blot 进行验证。通过荧光测定和 Western blot 评估 VPA 和 LEV 对 caspase（-3、-8 和-9）活性的时间依赖性影响。
VPA 浓度高于 5mM 时会导致 DNA 片段化增加，与凋亡相关的基因和蛋白表达发生变化，并激活 caspase 级联。然而，LEV 暴露不会影响 DNA 片段化，在所有使用的剂量下，LEV 处理的细胞中均未观察到凋亡机制的调节。
高浓度 VPA 显著刺激凋亡，通过调节负责细胞死亡的基因和蛋白的表达，并通过激活 caspase 级联来实现。LEV 则未观察到这些作用。这些数据表明，VPA 应作为治疗卵巢癌的抗癌药物进行认真评估。
