Natural anthraquinone compound emodin as a novel inhibitor of aurora A kinase: A pilot study

Aurora kinase A (AURKA) carries out an essential role in proliferation and involves in cisplatin resistance in various cancer cells. Overexpression of AURKA is associated with the poor prognosis of cancer patients. Thus, AURKA has been considered as a target for cancer therapy. Developing AURKA inhibitors became an important issue in cancer therapy. A natural compound emodin mainly extracted from rhubarbs possesses anti-cancer properties. However, the effect of emodin on AURKA has never been investigated. In the present study, molecular docking analysis indicated that emodin interacts with AURKA protein active site. We also found nine emodin analogues from Key Organic database by using ChemBioFinder software. Among that, one analogue 8L-902 showed a similar anti-cancer effect as emodin. The bindings of emodin and 8L-902 on AURKA protein were confirmed by cellular thermal shift assay. Furthermore, emodin inhibited the AURKA kinase activity in vitro and enhanced the cisplatin-DNA adduct level in a resistant ovarian cancer cell line. It seems that emodin may have the potential to inhibit cancer cell growth and enhance cisplatin therapy in cancer with resistance. Collectively, our finding reveals a novel AURKA inhibitor, emodin, which may be vulnerable to ovarian cancer therapy in the future.     

Aurora kinase inhibitor ZM447439 induces apoptosis via mitochondrial pathways

ZM447439 (ZM) is a potent and selective inhibitor of aurora-A and -B kinase with putative anti-tumoral activity. Inhibitors of aurora kinases were shown to induce apoptosis in vitro and in vivo. To investigate the underlying mechanisms, cell death pathways triggered by ZM was analysed in HCT-116 colorectal cancer cells. Through correlation of polyploidization and apoptosis in different knockout cells, the interrelation of these cellular responses to ZM was investigated. ZM induced apoptosis in a concentration- and time-dependent manner. ZM-induced apoptosis was associated with an upregulation of p53, breakdown of the mitochondrial membrane potential (ΔΨm) and activation of caspase-3. To precisely define key components for ZM-induced apoptosis, knockout cells lacking p53, Bak, Bax or both Bak and Bax were used. Lack of p53 reduced ZM-induced apoptosis and breakdown of ΔΨm, while lack of Bak, Bax or both almost completely inhibited apoptosis and breakdown of ΔΨm. Since no difference in apoptosis induction was detectable between HCT-116 cells lacking Bak, Bax or both, apoptosis induction depended non-redundantly on both Bak and Bax. Phenomenally, ZM induced notable polyploidization in all examined cells, especially in p53−/− cells. A correlation between polyploidization and apoptosis was observed in wild-type, and also in p53−/− cells, albeit with a modest extent of apoptosis. Moreover, in Bak−/−, Bax−/− and Bak/Bax−/− cells apoptosis was totally inhibited in spite of the strongest polyploidization, suggesting apoptosis may be a secondary event following polyploidization in HCT-116 cells. Thus ZM-induced apoptosis depends not only on polyploidization, but also on the intracellular apoptotic signaling.     

Aurora kinase targeted therapeutics in oncology: past,present and future

Aurora A, B and C are a family of serine-threonine protein kinases that regulate distinct functions of the mitotic phase of the cell cycle. All three Auroras are overexpressed in human cancers with an associated polyploid phenotype. Crystal structures of Aurora A or B with bound small molecular inhibitors have provided detailed insight of the active site, mode of binding and hotspots for developing resistance through point mutations. Structural studies have aided fragment-based rational drug discovery of Aurora inhibitors, including compounds specific for Aurora A or B. Aurora inhibitors have excellent antitumor activity in rodent models of cancer. At present, Aurora inhibitors are being evaluated in Phase I trials. The future holds promise for rational combinations in both solid and hematological malignancies.     

Aurora kinase A inhibitors: promising agents in antitumoral therapy

Introduction: Aurora proteins are serine/threonine kinases with critical functions during mitosis. Aurora A, one of the members of this family, participates in crucial processes including mitotic entry, DNA damage checkpoint recovery and centrosome and spindle maturation. Aurora A is frequently overexpressed in human cancers and, when inhibited, impairs cell proliferation.

Areas covered: Here, we review the preclinical studies that support the use of Aurora A inhibitors in antitumoral strategies. We also discuss past or current clinical trials using Aurora A inhibitors in multiple tumor types. We pay special attention to Alisertib, a potent and selective Aurora A inhibitor currently in Phase III.

Expert opinion: The potential of Aurora A inhibitors in the treatment of cancer depends on many factors, mainly related with the molecular status of tumor cells. Yet, we still need to find proper biomarkers to select those patients that better react to Aurora A inhibitors. Furthermore, their effect could significantly improve when used in combination with other drugs. Although some clinical trials are already testing the cooperative effect of different antitumoral drugs, additional preclinical studies are necessary to establish the best combinations. Here, we discuss some possibilities that could be explored in future studies.     

Aurora激酶抑制剂研究进展

Aurora激酶是细胞有丝分裂相关的一类丝氧酸/苏氨酸激酶,在细胞周期调控中起着重要的作用,研究发现Aurora激酶在多数血液恶性肿瘤和实体瘤中均高表达,表明Aurora激酶是抗肿瘤药物研究的重要新靶点之一.本文主要围绕Aurora家族的三个成员,对其生物学功能及其与肿瘤的关系、抑制剂的研究进展及其研究策略进行综述.     

MLN8237 (alisertib) and its role in peripheral T-cell lymphoma

The Seventh IBC Annual Conference on Anticoagulant, Antithrombotic and Thrombolytic Therapy took place in Boston, MA from October 21 - 24, 1996. These conferences have now achieved an annual updated forum to address recent developments in this field.     

Aurora激酶及其抑制剂的研究进展

目的 从结构出发介绍Aurora激酶及其抑制剂的研究进展。方法 总结 Aurora激酶抑制剂骨架特征和结合模式,以及进入临床的Aurora激酶抑制剂的研究进展。结果和结论 Aurora激酶家族是肿瘤治疗的一个新兴靶标。腺嘌呤骨架可能是设计高活性Aurora激酶抑制剂的重要母核。     

Vincristine potentiates the anti-proliferative effect of an aurora kinase inhibitor, VE-465, in myeloid leukemia cells

Aurora kinases play an essential role in the regulation of mitosis. The kinases are overexpressed in a variety of cancer cells and are involved in tumorgenesis. Although aurora kinase inhibitors are potential agents for treatment of leukemia, the establishment of efficacious combination therapies is an attractive approach for making good use of these agents. In this study, we examined the effects of a specific aurora kinase inhibitor, VE-465, in combination with various conventional anti-leukemia agents, including doxorubicin, daunorubicin, idarubicin, mitoxantron, cytosine arabinoside, vincristine and etoposide, on acute myeloid leukemia cell lines (HL60, U937, THP-1 and KY821), chronic myeloid leukemia cell lines (KCL22, K562 and KU812) and primary leukemia cells. We found that a combination of VE-465 and vincristine had a synergistic/additive inhibitory effect on the growth of leukemia cells. VE-465 initially increased G2/M-phase cells, followed by induction of sub-G1 cells. Vincristine enhanced this effect of VE-465. The combination of VE-465 and vincristine increased the levels of cleaved caspase 3, cleaved caspase 7, cleaved caspase 9, cleaved PARP and Phospho-Chk2, suggesting that the combination caused Chk2-mediated activation of the G2/M checkpoint, resulting in sequential induction of apoptosis. Interestingly, the combination markedly decreased the level of Phospho-ERK1/2, suggesting that the combination alters a network of cellular signaling pathways. In contrast, combinations of VE-465 and other agents showed no synergistic inhibitory effect but rather had an antagonistic effect. In conclusion, our results indicate the utility of the combination of VE-465 and vincristine as a potential therapy for myeloid leukemia.     

表皮生长因子受体多态性对酪氨酸激酶抑制剂药效学影响的研究进展

目前表皮生长因子受体（EGFR）的酪氨酸激酶抑制剂（TKI）在治疗非小细胞肺癌中得到广泛应用。本文回顾了影响酪氨酸激酶抑制剂药效的EGFR基因多态性以及相关的EGFR基因突变位点对酪氨酸激酶抑制剂吉非替尼治疗非小细胞肺癌的药效发挥产生何种影响的相关研究,说明EGFR的基因多态性对酪氨酸激酶抑制剂的药效发挥产生了重要的作用。     

Danusertib,an aurora kinase inhibitor

Introduction: Drugs that interfere with the normal progression of mitosis belong to the most successful cytotoxic agents currently used for anticancer treatment. Aurora kinases are serine/threonine kinases that function as key regulators of mitosis and are frequently overexpressed in human cancers. The use of several small molecule aurora kinase inhibitors as potential anticancer therapeutic is being investigated. Danusertib (formerly PHA-739358) is a small ATP competitive molecule that inhibits aurora A, B and C kinases. Interestingly, danusertib also inhibits several receptor tyrosine kinases such as Abl, Ret, FGFR-1 and TrkA. These tyrosine kinases are involved in the pathogenesis of a variety of malignancies and the observed multi-target inhibition may increase the antitumor activity resulting in extending the indication. Danusertib was one of the first aurora kinase inhibitors to enter the clinic and has been studied in Phase I and II trials.

Areas covered: This review provides an updated summary of preclinical and clinical experience with danusertib up to July 2011.

Expert opinion: Future studies with danusertib should focus on the possibility of combining this agent with other targeted anticancer agents, chemotherapy or radiotherapy. As a single agent, danusertib may show more promise in the treatment of leukemias than in solid tumors.     

RNA干扰Aurora A表达对人子宫内膜癌细胞的生长与细胞周期的影响

目的 探讨应用RNA干扰技术抑制Aurora A基因表达,并研究Aurora A基因表达下调对人子宫内膜癌细胞生长和细胞周期分布的影响.方法 用RNA干扰法抑制Aurora A的蛋白表达,RT-PCR及Western blot方法 检测Aurora A mRNA和蛋白表达,流式细胞仪检测细胞周期分布的变化,四氮唑盐法(MTT)检测转染前后细胞生长抑制率变化.结果 siRNA Aurora A可明显降低Aurora A mRNA和蛋白的表达,siRNA Aurora A导入Ishikawa细胞48 h后,细胞的生长被抑制,细胞周期阻滞于G2/M期和S期;细胞的凋亡率明显升高.结论下调AuroraA表达可抑制人子宫内膜癌细胞系Ishikawa的增殖,同时导致细胞阻滞于G2/M期及S期并且促进细胞凋亡.     

A Specific Pharmacophore Model of Aurora B Kinase Inhibitors and Virtual Screening Studies Based on it

In this study, 3D‐pharmacophore models of Aurora B kinase inhibitors have been developed by using HipHop and HypoGen modules in Catalyst software package. The best pharmacophore model, Hypo1, which has the highest correlation coefficient (0.9911), consists of one hydrogen‐bond acceptor, one hydrogen‐bond donor, one hydrophobic aliphatic moiety and one ring aromatic feature. Hypo1 was validated by test set and cross‐validation methods. And the specificity of Hypo1 to Aurora B inhibitors was examined with the use of selective inhibitors against Aurora B and its paralogue Aurora A. The results clearly indicate that Hypo1 can differentiate selective inhibitors of Aurora B from those of Aurora A, and the ring aromatic feature likely plays some important roles for the specificity of Hypo1. Then Hypo1 was used as a 3D query to screen several databases including Specs, NCI, Maybridge and Chinese Nature Product Database (CNPD) for identifying new inhibitors of Aurora B. The hit compounds were subsequently subjected to filtering by Lipinski’s rule of five and docking studies to refine the retrieved hits, and some compounds selected from the top ranked hits have been suggested for further experimental assay studies.     

FR180204, a novel and selective inhibitor of extracellular signal-regulated kinase,ameliorates collagen-induced arthritis in mice

Extracellular signal-regulated kinase (ERK), a serine/threonine protein kinase of the mitogen-activated protein kinase superfamily, is activated by various stimuli in inflammatory cells. We recently described FR180204 (5-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)-1H-pyrazolo[3,4-c]pyridazin-3-amine), a novel selective ERK inhibitor. In this paper, we investigated the effect of FR180204 on collagen-induced arthritis (CIA) in DBA/1 mice, an animal model of rheumatoid arthritis (RA) mediated by type II collagen (CII)-reactive T cells and anti-CII antibodies. Preventive administration of FR180204 (100 mg/kg, i.p., b.i.d.) significantly ameliorated the clinical arthritis and body weight loss occurring in the CIA mice. Further, FR180204-treated mice showed a significant decrease in plasma anti-CII antibody levels (62%). FR180204 also attenuated delayed-type hypersensitivity in CII-immunized DBA/1 mice, an inflammatory response elicited by CII-reactive T cells, in a dose-dependent manner (52 and 62% inhibition at 32 and 100 mg/kg, respectively). Moreover, FR180204 inhibited in vitro CII-induced proliferation of lymph node cells prepared from CII-immunized mice, in which CII-specific T cells are known to undergo specific proliferation. In conclusion, our results suggest that ERK regulates both the cell-mediated and humoral immune responses in the development of CIA. ERK inhibitors may be useful as therapeutic reagents for the treatment of RA.     

EGFR和ErbB2双重酪氨酸激酶

拉帕替尼是一种人源2型表皮生长因子受体(HER2)和表皮生长因子受体(EGFR)双重酪氨酸激酶抑制剂,与卡培他滨联用治疗女性HER2阳性的乳腺癌。我们利用MEDLINE进行关键词为拉帕替尼的文献检索,对其药理作用、药动学、临床疗效及安全性,药物相互作用等进行综述。     

A Dual Non‐ATP Analogue Inhibitor of Aurora Kinases A and B,Derived from Resorcinol with a Mixed Mode of Inhibition

Aurora kinases are the most commonly targeted mitotic kinases in the intervention of cancer progression. Here, we report a resorcinol derivative, 5‐methyl‐4‐(2‐thiazolylazo) resorcinol (PTK66), a dual inhibitor of Aurora A and Aurora B kinases. PTK66 is a surface binding non‐ATP analogue inhibitor that shows a mixed pattern of inhibition against both of Aurora A and B kinases. The in vitro IC₅₀ is approximately 47 and 40 μm for Aurora A and Aurora B kinases, respectively. In cellular systems, PTK66 exhibits a substantially low cytotoxicity at micromolar concentrations but it can induce aneuploidy under similar dosages as a consequence of Aurora kinase inhibition. This result was corroborated by a drop in the histone H3 (S10) phosphorylation level detected via Western blot analysis using three different cell types. Altogether, our findings indicate that the ligand containing resorcinol backbone is one of the novel scaffolds targeting the Aurora family of kinases, which could be a target for antineoplastic drug development.