Addition of anticancer agents enhances freezing-induced prostate cancer cell death: implications of mitochondrial involvement
Addition of anticancer agents enhances freezing-induced prostate cancer cell death: implications of mitochondrial involvement
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DOI：
10.1016/j.cryobiol.2004.05.003
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发表时间：
2004-08-01
期刊：
影响因子：
2.7
通讯作者：
Baust, JG
中科院分区：
文献类型：
--
作者：
Clarke, DM;Baust, JM;Baust, JG
最近的证据表明，成功治疗前列腺癌可能需要辅助治疗。因此，更好地理解目前治疗中涉及的分子机制可能会通过为辅助治疗提供基础而提高疗效。在这项研究中，我们证明了在前列腺癌细胞（PC-3）模型中冷冻（-15 ℃）之前亚致死浓度的化疗剂的组合导致比单独的任一种治疗增强的功效。形态学分析显示，坏死似乎是辅助（体外）建模后细胞死亡的普遍模式，但分子分析表明，冷冻和化疗通过调节Bcl-2蛋白家族的相对成员差异激活凋亡级联反应。冷冻导致抗凋亡Bcl-2蛋白的时间依赖性增加，而化疗导致促凋亡Bax蛋白的增加。抗凋亡Bcl-2蛋白水平在暴露于冷冻后增加超过3倍。5-氟尿嘧啶（5-FU）在药物暴露期间导致促凋亡Bax水平增加2倍。Bax的增加在5-FU/冷冻组合后也是明显的，而Bcl-2水平维持在或低于对照水平。这导致Bcl-2与Bax比率向促死亡趋势转变。其他有效的冷冻/化疗组合也被发现提供类似的效果。与对照组相比，顺铂/冷冻组合导致Bax与Bcl-2的比率增加4倍，这表示比5-FU/冷冻组合模型增加2倍。这种增加可能导致在13天恢复期内观察到的细胞数量持续减少。此外，加入凋亡半胱天冬酶抑制剂不能保护培养物在联合处理后免于细胞死亡。总之，这些数据表明，Bcl-2和Bax不仅可能在冷冻/化疗组合的功效中发挥重要作用，而且两者之间的平衡可能决定系统破坏的作用和程度。(C)2004年爱思唯尔公司All rights reserved.
Recent evidence suggests that the successful treatment of prostate cancer may require adjuvant therapies. Accordingly, a better understanding of the molecular mechanisms involved in current treatments may lead to enhanced efficacy by providing a basis for adjuvant therapies. In this study, we demonstrate that the combination of sub-lethal concentrations of chemotherapeutic agents prior to freezing (-15degreesC) in a prostate cancer cell (PC-3) model results in enhanced efficacy over either treatment alone. Morphological analysis revealed that necrosis appeared to be the prevalent mode of cell death following adjuvant (in vitro) modeling, yet molecular analysis indicated that freezing and chemotherapy differentially activated apoptotic cascades through modulating opposing members of the Bcl-2 protein family. Freezing results in a time-dependent increase of the antiapoptotic Bcl-2 protein, while chemotherapy results in an increase of the pro-apoptotic Bax protein. Anti-apoptotic Bcl-2 protein levels increase over 3-fold following exposure to freezing. 5-Fluorouracil (5-FU) causes pro-apoptotic Bax levels to increase 2-fold during the drug exposure. The increase in Bax was also apparent following the combination of 5-FU/freezing, while Bcl-2 levels were maintained at or below control levels. This led to a shift in the Bcl-2 to Bax ratio to a pro-death tendency. Other effective cryo/chemo combinations were also found to provide similar effects. The combination of cisplatin/freezing resulted in a 4-fold increase in the ratio of Bax to Bcl-2 when compared to controls, which represented a 2-fold increase over the 5-FU/freezing-combination model. This increase may contribute to the continued reduction in cell number observed during the 13-day recovery period, Additionally, the addition of an apoptotic caspase inhibitor was not able to protect cultures from cell death following combination treatment. In conclusion, the data suggest that both Bcl-2 and Bax may, not only, play an important role in the efficacy of the cryo/chemo combination, but also the balance between the two may determine the role and extent of system destruction. (C) 2004 Elsevier Inc. All rights reserved.