Damrot J, Nübel T, Epe B, Roos W P, Kaina B, Fritz G
Department of Toxicology, University of Mainz, Mainz, Germany.
Br J Pharmacol. 2006 Dec;149(8):988-97. doi: 10.1038/sj.bjp.0706953. Epub 2006 Nov 6.
3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) are frequently used lipid-lowering drugs. Moreover, they exert pleiotropic effects on cellular stress responses and death. Here, we analysed whether lovastatin affects the sensitivity of primary human endothelial cells (HUVEC) to the anticancer drug doxorubicin.
We investigated whether pretreatment of HUVEC with low dose of lovastatin influences the cellular sensitivity to doxorubicin. To this end, cell viability, proliferation and apoptosis as well as DNA damage-triggered stress response were analysed.
Lovastatin reduced the cytotoxic potency of doxorubicin in HUVEC. Lovastatin attenuated the doxorubicin-induced increase in p53 as well as activation of checkpoint kinase (Chk-1) and stress-activated protein kinase/c-Jun-N-terminal kinase (SAPK/JNK). Acquired doxorubicin resistance was independent of alterations in doxorubicin efflux and cell cycle progression. Also, doxorubicin-triggered production of reactive oxygen species (ROS) and formation of oxidative DNA lesions remained unaffected by lovastatin. However, lovastatin impaired DNA strand break formation induced by doxorubicin. Notably, lovastatin also conferred cross-resistance to the cytotoxic and genotoxic effects of etoposide, indicating that lovastatin shields topoisomerase II against poisons.
Based on these data, we suggest that lovastatin-mediated resistance to topoisomerase II inhibitors is due to a reduction in DNA damage and, hence, it attenuates stress responses leading to cell death that are triggered by DNA damage. Therefore, lovastatin might be useful clinically for alleviating side-effects of anticancer therapies that include topoisomerase II inhibitors.
3-羟基-3-甲基戊二酰辅酶A(HMG-CoA)还原酶抑制剂(他汀类药物)是常用的降脂药物。此外,它们对细胞应激反应和死亡具有多效性作用。在此,我们分析了洛伐他汀是否会影响原代人内皮细胞(HUVEC)对抗癌药物阿霉素的敏感性。
我们研究了用低剂量洛伐他汀预处理HUVEC是否会影响细胞对阿霉素的敏感性。为此,分析了细胞活力、增殖和凋亡以及DNA损伤引发的应激反应。
洛伐他汀降低了阿霉素对HUVEC的细胞毒性。洛伐他汀减弱了阿霉素诱导的p53增加以及检查点激酶(Chk-1)和应激激活蛋白激酶/c-Jun氨基末端激酶(SAPK/JNK)的激活。获得性阿霉素耐药性与阿霉素外排和细胞周期进程的改变无关。此外,阿霉素引发的活性氧(ROS)产生和氧化性DNA损伤的形成不受洛伐他汀影响。然而,洛伐他汀损害了阿霉素诱导的DNA链断裂形成。值得注意的是,洛伐他汀还赋予了对依托泊苷细胞毒性和基因毒性作用的交叉耐药性,表明洛伐他汀保护拓扑异构酶II免受毒物影响。
基于这些数据,我们认为洛伐他汀介导的对拓扑异构酶II抑制剂的耐药性是由于DNA损伤减少,因此,它减弱了由DNA损伤引发的导致细胞死亡的应激反应。因此,洛伐他汀在临床上可能有助于减轻包括拓扑异构酶II抑制剂在内的抗癌治疗的副作用。