组蛋白去乙酰化酶抑制剂治疗血液系统肿瘤的作用机制及临床应用

组蛋白去乙酰化酶抑制剂(HDAI)使组蛋白和非组蛋白乙酰化,然后通过多条细胞内途径诱导血液肿瘤细胞的凋亡和分化,并使细胞周期阻滞,以抑制血液肿瘤细胞增殖,发挥治疗恶性血液病的作用。HDAI治疗血液系统肿瘤作用机制的研究推动了其临床试验的进展。本文介绍了国外近年来HDAI治疗血液系统肿瘤作用机制及临床应用的研究进展。     

具有去甲斑蝥素结构的HDAC抑制剂的设计与合成

目的：设计与合成以去甲斑蝥素为骨架的苯甲酰胺类组蛋白去乙酰化酶抑制剂。方法利用拼合原理,将去甲斑蝥素的活性结构片段,引入具有不同取代基的苯甲酰胺类组蛋白去乙酰化酶抑制剂中,探索性设计并合成了2个未经报道的全新化合物。结果目标化合物为全新未报道化合物,结构经质谱、氢谱和碳谱确认。结论设计思想合理,合成方法温和,简便,适合该类化合物的合成。     

组蛋白去乙酰酶抑制剂的研究进展

组蛋白乙酰转移酶(histone acetyltransferase,HAT)和组蛋白去乙酰酶(histone deacetylase,HDAC)通过对组蛋白氮端氨基酸残基进行乙酰化或去乙酰化,调节组蛋白的乙酰化水平,调控基因表达,该过程与癌症的发生具有密切的关系.组蛋白去乙酰酶抑制剂通过增加细胞内组蛋白的乙酰化程度,提高p21等基因的表达水平等途径,抑制肿瘤细胞的增殖,诱导细胞分化和(或)凋亡.该文对HDAC抑制剂的研究进展进行系统的综述.     

Developing histone deacetylase inhibitors in the therapeutic armamentarium of pancreatic adenocarcinoma

Introduction: Histone deacetylases (HDACs) are commonly dysregulated in pancreatic adenocarcinoma (PA) and have a central role in the development and progression of the disease. HDAC is a family of enzymes involved in deacetylation of lysine residues on histone and non-histone proteins. Deacetylation of histone proteins leads to compaction of the DNA/histone complex resulting in inhibition of gene expression. Deacetylation of non-histone proteins can affect the stability and function of key proteins leading to dysregulation of cellular signaling pathways. HDAC inhibitors have been shown to potentiate the antiproliferative and proapoptotic effects of several cytotoxic agents, in vitro and in vivo PA xenograft models.

Areas covered: The areas covered include the biology and function of the HDAC isoenzymes and their significant role in multiple oncogenic pathways in PA. Preclinical and clinical trials evaluating HDAC inhibitors are also reviewed.

Expert opinion: Despite discouraging early phase clinical trials evaluating HDAC inhibitors in PA, this strategy deserves further evaluation guided by better preclinical studies in identifying the role of specific HDAC isoenzyme inhibitors in PA. Evaluation of the effects of HDAC inhibitors on PA stem cell function and epithelial to mesenchymal transformation is also an evolving area that holds future potential for these agents. Such preclinical studies will yield insight into the functionality of HDAC isoenzymes, which can then be translated into rationally designed clinical trials. One such strategy could focus on HDAC inhibition employed in combination with proteasome inhibition targeting the aggresome pathway in PA.     

Histone deacetylase inhibitors for treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers in the world. Surgical resection has been considered the optimal treatment approach, but only a small proportion of patients are suitable candidates for surgery, and the relapse rate is high. Approaches to prevent recurrence, including chemoembolization before and adjuvant therapy after surgery, have proven to have a limited benefit; liver transplantation is successful in treating limited-stage HCC because only a minority of patients qualify for transplantation. Therefore, new therapeutic strategies are urgently needed. Because in addition to the classical genetic mechanisms of deletion or inactivating point mutations, epigenetic alterations, such as hyperacetylation of the chromatin-associated histones (responsible for gene silencing), are believed to be involved in the development and progression of HCC, novel compounds endowed with a histone deacetylase (HDAC) inhibitory activity are an attractive therapeutic approach. In particular, pre-clinical results obtained using HA-But, an HDAC inhibitor in which butyric acid residues are esterified to a hyaluronic acid backbone and characterized by a high affinity for the membrane receptor CD44, indicated that this class of compounds may represent a promising approach for hepatocellular carcinoma treatment.     

Panobinostat for the treatment of multiple myeloma

Introduction : Multiple myeloma (MM) is a B-cell malignancy characterized by proliferation of monoclonal plasma cells in the bone marrow. Although new therapeutic options have been introduced and response rates have improved in recent years, MM still remains incurable and new treatment options are urgently needed. The histone deacetylase inhibitors (HDACi) are a new class of anticancer agents in early clinical development in many malignancies including MM. HDACi target the enzyme histone deacetylase (HDAC) involved in the deacetylation of histone and non-histone cellular proteins that play important roles in epigenetic regulation of gene expression inducing death, apoptosis and cell cycle arrest in cancer cells. Panobinostat (LBH589) is a highly potent HDACi with demonstrated antitumor activities at low nanomolar concentration in several preclinical studies and its clinical efficacy is currently under investigation in several clinical trials.

Area covered : In this review the authors discuss the role of HDACs in the regulation of gene expression and the biological mechanisms mediating the anticancer effects of HDACi with particular focus on the recent development of panobinostat as anti-MM agent in preclinical and clinical studies.

Expert opinion : As a ‘multi-target' drug, panobinostat appears attractive as potential anti-MM therapeutic for its ability to modulate a variety of biological pathways essential in MM biology. This ‘multi-target' property of panobinostat may also be one its major shortcomings, and a better understanding of its mechanisms of action and targets will permit to identify the best combination therapies that will ultimately overcome and improve outcomes in MM patients.     

组蛋白去乙酰化酶抑制剂的抗抑郁前景

抑郁症是一种发病率较高的严重精神疾病,目前对其病理机制尚未全面了解,临床治疗效果十分有限。最近的研究表明,发生在大脑特定脑区的表观遗传调控——即不改变脱氧核糖核酸(deoxyribonucleic acid, DNA)编码的情况下调节基因活性,可能是环境因素与个体遗传相互作用以影响抑郁症发病风险的关键机制。因此,靶向表观遗传调控的药物可能成为开发抗抑郁药的新方向。组蛋白去乙酰化酶抑制剂(histone deacetylase inhibitors,HDACi)是一类具有抑制组蛋白去乙酰化酶(histone deacetylase, HDAC)活性的化合物。本文从HDAC与抑郁症的关系入手,集中讨论了在临床前研究中具有抗抑郁药效的HDACi,及其治疗抑郁症的潜在机制与主要局限性,并对未来研究进行了展望和讨论。     

Panobinostat for the treatment of relapsed or relapsed/refractory multiple myeloma: pharmacology and clinical outcomes

Recently, outcomes for patients with multiple myeloma have improved dramatically due to improved and innovative therapies. However, most patients will either relapse or become refractory to current therapy. Thus, a significant unmet need remains for novel agents to treat this patient population. Panobinostat, a potent pan-deacetylase inhibitor with a unique mechanism of action targeting both epigenetic regulation of gene expression and protein metabolism, has preclinical synergy with a number of agents, including the proteasome inhibitor bortezomib. In a phase 3 trial of panobinostat with bortezomib and dexamethasone, addition of panobinostat significantly prolonged the median progression-free survival of patients with relapsed or relapsed and refractory multiple myeloma. This review focuses on clinical development of panobinostat, with particular emphasis on pharmacokinetics and adverse event management.     

Targeting triple negative breast cancer with histone deacetylase inhibitors

Introduction: Triple negative breast cancer (TNBC) is a heterogeneous disease characterized by poor outcomes, higher rates of relapse, lack of biomarkers for rational use of targeted treatments and insensitivity to current available treatments. Histone deacetylase inhibitors (HDACis) perform multiple cytotoxic actions and are emerging as promising multifunctional agents in TNBC.

Areas covered: This review focuses on the challenges so far addressed in the targeted treatment of TNBC and explores the various mechanisms by which HDACis control cancer cell growth, tumor progression and metastases. Pivotal preclinical trials on HDACis like panobinostat, vorinostat, and entinostat show that these epigenetic agents exert an anti-proliferative effect on TNBC cells and control tumor growth by multiple mechanisms of action, including apoptosis and regulation of the epithelial to mesenchimal transition (EMT). Combination studies have reported the synergism of HDACis with other anticancer agents.

Expert opinion: In recent years, treatment of TNBC has recorded a high number of failures in the development of targeted agents. HDACis alone or in combination strategies show promising activity in TNBC and could have implications for the future targeted treatment of TNBC patients. Future research should identify which agent synergizes better with HDACis and which patient will benefit more from these epigenetic agents.     

组蛋白去乙酰化酶抑制药研究现状

组蛋白去乙酰化酶抑制药具有的锌指结构与组蛋白乙酰化赖氨酸残基侧链结构相似,可通过竞争性抑制组蛋白去乙酰化酶活性而提高组蛋白乙酰化水平,改变特定基因的转录与表达水平,抑制细胞增殖,诱导细胞分化与凋亡,从而发挥多种药理作用尤其是抗癌作用。多种组蛋白去乙酰化酶抑制药已得到了深入的研究,并在临床试验中显示出良好的治疗效果。     

Finding the place of histone deacetylase inhibitors in prostate cancer therapy

Histone deacetylase inhibitors (HDACIs) are showing promise as therapeutic agents for hematological malignancies and solid tumors. In the case of prostate cancer, HDACIs are effective at inhibiting proliferation and inducing apoptosis in a range of in vitro and in vivo experimental models. Recent studies have revealed that the actions of HDACIs in prostate cancer cells extend beyond regulation of histone acetylation and affect proteins involved in maintaining cellular homeostasis and tumor progression, including the androgen receptor, p21^WAF1 and VEGF. The broad spectrum of HDACI targets has allowed rational design of combinations with other therapeutic agents to target multiple pathways involved in prostate cancer progression, including angiogenesis and androgen signaling. In particular, synergistic inhibition of prostate cancer cell growth has been demonstrated using HDACIs in combination with radio- and chemo-therapy, Apo2L/TRAIL, angiogenesis inhibitors, heat-shock protein 90 inhibitors and androgen receptor antagonists. This review examines the current understanding of the actions of HDACIs in prostate cancer cells, both in a laboratory and a clinical context and discusses the potential utility of combination strategies for the treatment of prostate cancer.     

Histone deacetylase inhibitors in oral squamous cell carcinoma treatment

Introduction: The involvement of the histone deacetylases (HDACs) family in tumor development and progression is well demonstrated. HDAC inhibitors (HDACis) constitute a novel, heterogeneous family of highly selective anticancer agents that inhibit HDACs and present significant antitumor activity in several human malignancies, including oral squamous cell carcinoma (OSCC).

Areas covered: This review summarizes the current research on the anticancer activity of HDACis against OSCC. The review also presents the molecular mechanisms of HDACis action and the existing studies evaluating their utilization in combined therapies of OSCC.

Expert opinion: The currently available data support evidence that HDACis may provide new therapeutic options against OSCC, decreasing treatment side effects and allowing a more conservative therapeutic approach. Future research should be focused on in vivo and clinical evaluation of their utilization as combined therapies or monotherapies. Before HDACis can be brought into clinical practice as treatment options for OSCC, further evaluation is needed to determine their optimal dosage, the appropriate duration of treatment and whether they should be used in combination or as stand-alone therapeutics.     

组蛋白去乙酰酶抑制剂联合应用治疗肿瘤的研究进展

组蛋白去乙酰酶(histone deacetylase,HDAC)抑制剂可促进组蛋白乙酰化,调节染色质结构和基因转录。临床前研究,Ⅰ和(或)Ⅱ期临床试验都已证实,HDAC的小分子抑制剂能够有效地促进抑癌基因表达,抑制肿瘤生长并诱导细胞凋亡。在多种肿瘤中都已观察到,HDAC抑制剂与其他抗肿瘤药物联合应用,可在较低的剂量下产生更好的疗效,而不良反应减轻。     

Histone deacetylase inhibitors in cancer therapy

Histones are a family of nuclear proteins that interact with DNA, resulting in DNA being wrapped around a core of histone octamer within the nucleosome. Acetylation/deacetylation of histones is an important mechanism that regulates gene expression and chromatin remodeling. Histone deacetylase (HDAC) inhibitors are a new class of chemotherapeutic drugs that regulate gene expression by enhancing the acetylation of histones, and thus inducing chromatin relaxation and altering gene expression. HDAC inhibitors have been shown in preclinical studies to have potent anticancer activities. A range of structurally diverse HDAC inhibitors have been purified as natural products or synthetically produced. Due to the promising preclinical activity of these agents, numerous clinical trials have been initiated. In this review, the results of published data of single agent and combination trials of these drugs are reviewed, with a focus on dosing, scheduling and toxicity. Although still early in drug development, there is a picture that is starting to develop as to the common toxicities and which tumors seem to be the most susceptible to this class of drugs.     

组蛋白去乙酰化酶抑制剂与炎症免疫性疾病

组蛋白去乙酰化酶抑制剂已经越来越多的被用于治疗肿瘤和白血病。近年来,组蛋白去乙酰化酶抑制剂作为潜在的抗炎免疫药为类风湿关节炎或红斑狼疮等的治疗提供了一种新的思路,它在炎症免疫性疾病中的作用机制越来越受到人们的关注。     

用于筛选组蛋白去乙酰化酶抑制剂细胞模型的验证

目的验证已建立的组蛋白去乙酰化酶(HDAC)抑制剂筛选细胞模型,并采用该模型进行药物筛选。方法采用脂质体转染法将含有TA1和TA2启动子元件的荧光素酶报道基因真核表达载体pTA1-Luc和pTA2-Luc导入COS-7细胞,G418筛选获得稳定转染上述报告基因系统的细胞克隆。以特异性HDAC抑制剂缩酯环肽FK228,N-辛二酰苯胺异羟肟酸(SAHA)和曲古抑菌素A(TSA)为阳性对照,通过测定荧光素酶活性评估TA1和TA2启动子对HDAC抑制剂的反应;并采用此细胞模型对其他抗肿瘤药物和植物提取物进行初步筛选。结果稳定转染的COS-pTA1及COS-pTA2细胞对HDAC抑制剂具有良好的浓度依赖性(FK228:相关系数为0.7236;SAHA:相关系数为0.7997;TSA为相关系数为0.9815;P<0.01),其中COS-pTA1的特点是灵敏度高,可以有效避免因样品活性低而出现漏检。COS-pTA2细胞的特点是检测背景低,特异性强,可以有效排除假阳性的标本。两种细胞模型的联合筛选,可以鉴定具有HDAC抑制活性的化合物。结论该细胞模型可用于筛选具有HDAC抑制活性的先导化合物。     

以二酮酸酯作为锌离子结合基团的组蛋白去乙酰化酶抑制剂的设计、合成及生物活性研究

组蛋白去乙酰化酶(histone deacetylases,HDACs)抑制剂可以在转录水平上调控基因表达,导致肿瘤细胞生长停滞,诱导肿瘤细胞分化和凋亡。目前应用最为广泛的氧肟酸结构可以与活性口袋底部锌离子螯合从而竞争性地抑制HDACs的去乙酰化作用,但是氧肟酸结构存在代谢不稳定和选择性差的缺点难以成药。本文以二酮酸酯结构作为潜在的锌离子结合基团对氧肟酸进行替代,共合成了8个目标化合物,并对其HDACs抑制活性和对多种肿瘤细胞株的抗增殖活性进行了研究。其中化合物CPUYS707对人髓系白血病细胞株U937的抗增殖活性GI50达到0.31μmol.L-1,优于阳性对照药物SAHA和MS-275。     

The safety of daratumumab for the treatment of multiple myeloma

Introduction: The overall survival of patients with multiple myeloma (MM) has changed dramatically in the last decade. MM remains an incurable plasma cell disorder but immunotherapy with monoclonal antibodies (MoAbs) has emerged as a promising treatment.

Areas covered: Fully published, clinical trials including patients with relapsed or refractory MM were reviewed. Safety data of daratumumab (DARA) single-agent or in combination regimens have been addressed. Additionally, infusion-related reactions, data on special populations, and DARA-interference with laboratory testing, including assessment of MM response in patients have also been addressed.

Expert opinion: Daratumumab both as single agent and in combination regimens has shown a favorable safety profile without significant increase in toxicities. Extensive clinical development of DARA is currently ongoing and given the efficacy that has been seen with this drug in clinical trials, DARA is likely to change the landscape of myeloma treatment.