Utilization of tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidinone as a cap moiety in design of novel histone deacetylase inhibitors

A series of novel 5,6,7,8-Tetrahydro[1]benzothieno[2,3-d]pyrimidin-4(3H)-one derivatives bearing a hydroxamic acid, 2-aminoanilide and hydrazide moieties as zinc-binding group (ZBG) were designed, synthesized and evaluated for the HDAC inhibition activity and antiproliferative activity. Most of the tested compounds displayed strong to moderate HDAC inhibitory activity. Some of these compounds showed potent anti-proliferative activity against human HepG2, MCF-7 and HCT-116 cell lines. In particular, compounds IVa, IVb, IXa and IXb exhibited significant anti-proliferative activity against the three cell lines tested compared to SAHA as a reference. Compound IVb is equipotent inhibitor for HDAC1 and HDAC2 as SAHA. It is evident that the presence of free hydroxamic acid group is essential for Zn binding affinity with maximal activity with a linker of aliphatic 6 carbons. Docking study results revealed that compound IVb could occupy the HDAC2 binding site and had the potential to exhibit antitumor activity through HDAC inhibition, which merits further investigation.     

丙戊酸与缺血性脑卒中相关研究进展

动脉粥样硬化和缺血性脑损伤是防治缺血性脑卒中所面临的两大难题,而细胞炎症损伤是它们的共同诱因。丙戊酸作为组蛋白去乙酰化酶抑制剂,具有抑制细胞炎症因子释放及保护神经的作用,所以丙戊酸可能是防治缺血性脑卒中的潜在治疗药物。本文从组蛋白去乙酰化酶对缺血性脑卒中的影响以及丙戊酸的抗炎机制两个方面进行综述。     

组蛋白脱乙酰酶抑制剂的抗癌作用

组蛋白乙酰转移酶和组蛋白脱乙酰酶分别催化组蛋白的乙酰化和脱乙酰基反应,调节组蛋白的乙酰化水平,从而调控基因表达。这些过程与恶性肿瘤的发生具有密切的关系。组蛋白脱乙酰酶抑制剂通过增加细胞内组蛋白的乙酰化程度,调节多种基因的表达水平,抑制肿瘤细胞的增殖、诱导细胞分化和凋亡。该文从抑制细胞增殖、诱导细胞分化、诱导细胞凋亡和抗血管形成等4个方面介绍组蛋白脱乙酰酶抑制剂的抗癌机制,并简要介绍它们的分类。     

Acetylation of H2AX on lysine 36 plays a key role in the DNA double-strand break repair pathway

Phosphorylation of H2AX functions to recruit DNA repair complexes to sites of DNA damage. Here, we report that H2AX is constitutively acetylated on lysine 36 (H2AXK36Ac) by the CBP/p300 acetyltransferases. H2AXK36Ac is required for cells to survive exposure to ionizing radiation; however, H2AXK36Ac levels are not increased by DNA damage. Further, acetylation of H2AX did not affect phosphorylation of H2AX or the formation of DNA damage foci. Finally, cells with a double mutation in both the H2AX acetylation and phosphorylation sites were more radiosensitive than cells containing individual mutations. H2AXK36Ac is therefore a novel, constitutive histone modification located within the histone core region which regulates radiation sensitivity independently of H2AX phosphorylation.     

层生镰孢菌产甲壳素脱乙酰酶发酵动力学

对层生镰孢菌产甲壳素脱乙酰酶的发酵动力学进行了研究。通过Logistic方程分别构建层生镰孢菌细胞生长、甲壳素脱乙酰酶（CDA）合成及糖基质消耗的非结构动力学模型,并利用1stOpt软件对该模型进行了模拟,采用Origin8.0软件得到了非线性曲线拟合图形及各模型参数。结果表明,各模型预测值与实验数据能较好地拟合,层生镰孢菌细胞的比生长速率在第15.52h达到峰值（μ_{m, x}）0.160h^-1;层生镰孢菌的底物比消耗速率在26.51h时达到峰值（μ_{m, s}）0.096h^-1;层生镰孢菌的甲壳素脱乙酰酶比合成速率19.40h达到峰值（μ_{m, p}）0.548U/(mL·h)。模型拟合和实验数据具有良好的适应性,基本上反映了层生镰孢菌发酵产酶过程的动力学特征,为今后的工业化规模生产提供理论依据。     

Synthesis and structure-activity relationship of histone deacetylase (HDAC) inhibitors with triazole-linked cap group

Histone deacetylase (HDAC) inhibition is a recent, clinically validated therapeutic strategy for cancer treatment. Small molecule HDAC inhibitors identified so far fall in to three distinct structural motifs: the zinc-binding group (ZBG), a hydrophobic linker, and a recognition cap group. Here we report the suitability of a 1,2,3-triazole ring as a surface recognition cap group-linking moiety in suberoylanilide hydroxamic acid-like (SAHA-like) HDAC inhibitors. Using “click” chemistry (Huisgen cycloaddition reaction), several triazole-linked SAHA-like hydroxamates were synthesized. Structure–activity relationship revealed that the position of the triazole moiety as well as the identity of the cap group markedly affected the in vitro HDAC inhibition and cell growth inhibitory activities of this class of compounds.