Activation of DNA damage response pathways as a consequence of anthracycline-DNA adduct formation
Activation of DNA damage response pathways as a consequence of anthracycline-DNA adduct formation
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DOI：
10.1016/j.bcp.2012.02.026
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发表时间：
2012-06-15
影响因子：
5.8
通讯作者：
Cutts, Suzanne M.
中科院分区：
文献类型：
--
作者：
Forrest, Robert A.;Swift, Lonnie P.;Cutts, Suzanne M.
临床上使用的抗肿瘤药物阿霉素的细胞毒性可以通过甲醛（内源性或外源性）增强，促进阿霉素-DNA加合物的形成。甲醛提供阿霉素与一条 DNA 链共价连接所需的碳，并通过氢键稳定阿霉素单加合物与另一条 DNA 链，其作用与链间交联非常相似。链间交联对细胞修复过程提出了重大挑战，需要激活大量 DNA 损伤反应蛋白来解决由此产生的 DNA 中间体和损伤。这项工作研究了阿霉素-DNA 加合物激活的 DNA 损伤反应蛋白。尽管 p53 在加合物的作用下在丝氨酸 15 处被磷酸化，但哺乳动物细胞的长期生长抑制不受 p53 状态的影响。使用 siRNA 技术和激酶抑制剂，我们观察到当信号蛋白激酶 ATM 和 ATR 的活性丧失时，细胞对阿霉素-DNA 加合物的敏感性增强。使用双胸苷阻断同步化的细胞在 ATR 敲低后对加合物引发的细胞死亡敏感，但相对不受 ATM 敲低的影响。 ATR 的缺失与药物诱导的 G(2)/M 阻滞的取消和有丝分裂灾难的诱导有关，而 ATM 的缺失与药物诱导的非同步细胞凋亡有关。因此，这些蛋白质可能是潜在的药物靶点，以实现对阿霉素-DNA 加合物形成疗法的协同细胞毒性反应。对这些蛋白激酶与细胞周期进程相关的分析表明，G2/M 检查点反应需要 AIR，而 ATM 似乎在 G(1) 介导的蒽环类加合物反应中发挥作用。 (C) 2012 Elsevier Inc. 保留所有权利。
The cytotoxicity of doxorubicin, a clinically used anti-neoplastic drug, can be enhanced by formaldehyde (either endogenous or exogenous) to promote the formation of doxorubicin-DNA adducts. Formaldehyde supplies the carbon required for the covalent linkage of doxorubicin to one strand of DNA, with hydrogen bonds stabilising the doxorubicin mono-adduct to the other strand of DNA, to act much like an interstrand crosslink. Interstrand crosslinks present a major challenge for cellular repair processes, requiring the activation of numerous DNA damage response proteins for resolution of the resulting DNA intermediates and damage. This work investigates DNA damage response proteins activated by doxorubicin-DNA adducts. Although p53 was phosphorylated at Serine 15 in response to adducts, long term growth inhibition of mammalian cells was not affected by p53 status. Using siRNA technology and kinase inhibitors we observed enhanced cellular sensitivity to doxorubicin-DNA adducts when the activity of the signalling protein kinases ATM and ATR were lost. Cells synchronised using a double thymidine block were sensitised to adduct-initiated cell death upon ATR knockdown, but relatively unaffected by ATM knockdown. Loss of ATR was associated with abrogation of a drug-induced G(2)/M block and induction of mitotic catastrophe, while loss of ATM was associated with drug-induced apoptosis in non-synchronised cells. These proteins may therefore be potential drug targets to achieve synergistic cytotoxic responses to doxorubicin-DNA adduct forming therapies. The analysis of these protein kinases with respect to cell cycle progression indicates that AIR is required for G2/M checkpoint responses while ATM appears to function in G(1) mediated responses to anthracycline adducts. (C) 2012 Elsevier Inc. All rights reserved.