Noack Katrin, Mahendrarajah Nisintha, Hennig Dorle, Schmidt Luisa, Grebien Florian, Hildebrand Dagmar, Christmann Markus, Kaina Bernd, Sellmer Andreas, Mahboobi Siavosh, Kubatzky Katharina, Heinzel Thorsten, Krämer Oliver H
Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Erlanger Allee 101, 07747, Jena, Germany.
Center for Molecular Biomedicine (CMB), Institute of Biochemistry and Biophysics, Friedrich-Schiller-University Jena, Hans-Knöll-Strasse 2, 07745, Jena, Germany.
Arch Toxicol. 2017 May;91(5):2191-2208. doi: 10.1007/s00204-016-1878-5. Epub 2016 Nov 2.
The treatment of acute promyelocytic leukemia (APL) with all-trans retinoic acid (ATRA) induces granulocytic differentiation. This process renders APL cells resistant to cytotoxic chemotherapies. Epigenetic regulators of the histone deacetylases (HDACs) family, which comprise four classes (I-IV), critically control the development and progression of APL. We set out to clarify the parameters that determine the interaction between ATRA and histone deacetylase inhibitors (HDACi). Our assays included drugs against class I HDACs (MS-275, VPA, and FK228), pan-HDACi (LBH589, SAHA), and the novel HDAC6-selective compound Marbostat-100. We demonstrate that ATRA protects APL cells from cytotoxic effects of SAHA, MS-275, and Marbostat-100. However, LBH589 and FK228, which have a superior substrate-inhibitor dissociation constant (Ki) for the class I deacetylases HDAC1, 2, 3, are resistant against ATRA-dependent cytoprotective effects. We further show that HDACi evoke DNA damage, measured as induction of phosphorylated histone H2AX and by the comet assay. The ability of ATRA to protect APL cells from the induction of p-H2AX by HDACi is a readout for the cytoprotective effects of ATRA. Moreover, ATRA increases the fraction of cells in the G1 phase, together with an accumulation of the cyclin-dependent kinase inhibitor p21 and a reduced expression of thymidylate synthase (TdS). In contrast, the ATRA-dependent activation of the transcription factors STAT1, NF-κB, and C/EBP hardly influences the responses of APL cells to HDACi. We conclude that the affinity of HDACi for class I HDACs determines whether such drugs can kill naïve and maturated APL cells.
用全反式维甲酸（ATRA）治疗急性早幼粒细胞白血病（APL）可诱导粒细胞分化。这一过程使APL细胞对细胞毒性化疗产生抗性。组蛋白脱乙酰酶（HDAC）家族的表观遗传调节因子包括四类（I - IV），对APL的发生发展起着关键控制作用。我们着手阐明决定ATRA与组蛋白脱乙酰酶抑制剂（HDACi）相互作用的参数。我们的实验包括针对I类HDAC的药物（MS - 275、VPA和FK228）、泛HDACi（LBH589、SAHA）以及新型HDAC6选择性化合物Marbostat - 100。我们证明ATRA可保护APL细胞免受SAHA、MS - 275和Marbostat - 100的细胞毒性作用。然而，LBH589和FK228对I类脱乙酰酶HDAC1、2、3具有更高的底物 - 抑制剂解离常数（Ki），它们对ATRA依赖的细胞保护作用具有抗性。我们进一步表明，HDACi会引发DNA损伤，通过磷酸化组蛋白H2AX的诱导以及彗星试验来衡量。ATRA保护APL细胞免受HDACi诱导的p - H2AX的能力是ATRA细胞保护作用的一个指标。此外，ATRA增加了处于G1期的细胞比例，同时伴有细胞周期蛋白依赖性激酶抑制剂p21的积累以及胸苷酸合成酶（TdS）表达的降低。相比之下，ATRA依赖的转录因子STAT1、NF - κB和C/EBP的激活对APL细胞对HDACi的反应几乎没有影响。我们得出结论，HDACi对I类HDAC的亲和力决定了此类药物是否能够杀死未成熟和成熟的APL细胞。
