scholarly journals The haploinsufficient tumor suppressor Tip60 negatively regulates the oncogenic Aurora B kinase

2019 ◽  
Author(s):  
Arnab Bose ◽  
Surabhi Sudevan ◽  
Vinay J. Rao ◽  
Hiroki Shima ◽  
Kazuhiko Igarashi ◽  
...  
Keyword(s):  
Tumor Suppressor ◽  
Aurora Kinase ◽  
Kinase Domain ◽  
Genomic Amplification ◽  
Aurora Kinases ◽  
Aurora Kinase B ◽  
Initial Event ◽  
Lysine Residues ◽  
Probable Outcome

AbstractThe Aurora kinases represent a group of serine/threonine kinases which are crucial regulators of mitosis. Dysregulated Aurora kinase B (AurkB) expression, stemming from genomic amplification, increased gene transcription or overexpression of its allosteric activators, is capable of initiating and sustaining malignant phenotypes. Although AurkB level in cells is well-orchestrated, studies that relate to its stability or activity, independent of mitosis, are lacking. We report that AurkB undergoes acetylation in vitro by lysine acetyltransferases (KATs) belonging to different families, namely by p300 and Tip60. The haploinsufficient tumor suppressor Tip60 acetylates two highly conserved lysine residues within the kinase domain of AurkB which not only impinges the protein stability but also its kinase activity. These results signify a probable outcome on the increase in “overall activity” of AurkB upon Tip60 downregulation, as observed under cancerous conditions. The present work, therefore, uncovers an important functional interplay between AurkB and Tip60, frailty of which may be an initial event in carcinogenesis.

Aurora Kinases in Childhood Acute Leukemia: The Promise of Aurora Kinase B As Drugable Target

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1476-1476
Author(s):  
Stefanie A. Segers ◽  
C. Michel Zwaan ◽  
Carla Exalto ◽  
Mirjam W.J. Luijendijk ◽  
Valerie S. Calvert ◽  
...  
Keyword(s):  
Acute Leukemia ◽  
Cell Lines ◽  
Aurora Kinase ◽  
Selective Inhibitor ◽  
Leukemic Cells ◽  
Aurora Kinases ◽  
Aurora Kinase B ◽  
Pediatric All ◽  
Childhood Acute Leukemia

Abstract Abstract 1476 AIM: Aurora kinases (AURK) A and B are known regulators of mitosis and are overexpressed in a large number of human cancers, including leukemia. Several AURK-inhibitors have shown anti-tumor activity in vitro and in vivo. However, the efficacy of AURK inhibition in the treatment of childhood acute leukemia is unexplored. We therefore investigated the effect of targeting AURKA and AURKB in leukemic cells of children with newly diagnosed acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). Materials & Methods: Affymetrix gene expression data of 297 ALL, 237 AML and 8 normal bone marrow (nBM) samples were analyzed for AURKA and B mRNA expression levels. Protein expression levels in 172 pediatric ALL and 10 nBM samples were determined with a reverse phase protein array. Functional studies were performed in ALL and AML cell lines, in which AURKA and B were silenced using a short hairpin RNA with a lentiviral delivery system or LNA-containing oligonucleotides. Sensitivity of leukemic cell lines to the AURKB-selective inhibitor Barasertib-hQPA (AZD1152-hQPA) was tested in vitro with an MTS assay. Results: AURKA and B mRNA levels were low in ALL and AML patients. In contrast, Aurora A and B proteins were expressed to a greater extent in patients (p<0.0002), especially in ALL cases with an E2A-PBX1 translocation (p<0.0001) than in nBM mononuclear cells. Silencing of AURKA by shRNA and by LNA-oligonucleotide caused no or only minor growth delay in several cell lines reflecting genetic subtypes typically found in pediatric ALL and AML. In contrast, silencing of AURKB resulted in proliferation arrest and apoptosis in these cells. Furthermore, 18 out of 20 ALL and AML cell lines tested were highly sensitive to the AURKB-selective inhibitor Barasertib-hQPA in the nanomolar range (IC50 = 19–233 nM) whereas less sensitivity was seen for other inhibitors. Conclusion: These data show that inhibition of AURKB but not AURKA has an anti-proliferative and pro-apoptotic effect on acute leukemic cells. Thus, targeting Aurora Kinase B may offer a new strategy to treat pediatric ALL and AML. Disclosures: No relevant conflicts of interest to declare.

Activity of Serono-AS703569, a Dual Inhibitor of Bcr-Abl and Aurora Kinases in Bcr-Abl Transformed Cells, Is Dependent On Aurora B Inhibition, and Is Not Affected by the Presence of the Highly Imatinib Resistant Bcr-Abl Mutation T315I.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3247-3247 ◽  
Author(s):  
Anna Katharina Seitz ◽  
Nikolas von Bubnoff ◽  
Samantha M. Sarno ◽  
Christian Peschel ◽  
Justus Duyster
Keyword(s):  
Cell Cycle ◽  
Kinase Inhibitor ◽  
Conflicts Of Interest ◽  
Point Mutations ◽  
Aurora Kinase ◽  
Aurora B ◽  
Dual Inhibitor ◽  
Aurora Kinases ◽  
Aurora Kinase B

Abstract Abstract 3247 Poster Board III-1 The tyrosine kinase inhibitor Imatinib is the gold standard in conventional treatment of CML. However, the emergence of resistance to IM remains a major problem. Alternative therapeutic strategies of IM-resistant BCR-ABL positive leukemias are urgently needed. One promising target for anticancer therapeutics is represented by the Aurora kinase family. These serine/threonine kinases are involved in regulating multiple steps of mitosis, including formation of bipolar spindle, chromosome alignment, spindle checkpoint function and cytokinesis. We report on studies accomplished with a small molecule inhibitor AS703569 (Merck Serono), which targets Bcr-Abl and Aurora kinases A-C. We could show that AS703569 exhibited strong anti-proliferative and pro-apoptotic activity against murine BaF3- cells ectopically expressing wild type (wt) or IM-resistant BCR-ABL mutants, including those harbouring the strongly resistant T315I mutation. This effect was observed already at rather low-AS703569 concentrations, at which Aurora- but not the Bcr-Abl kinase was inhibited. Furthermore, in cell cycle analysis we observed cells with a large 4N peak and DNA content more than 4N, indicating extensive polyploidisation, a consequence of continued cell cycle progression in the absence of cell division. Recent studies have revealed that this phenotype is based on suppression of Aurora B kinase activity, indicating that Aurora B inhibition is the major effect of AS703569 in Bcr-Abl positive cells. To confirm this assumption we designed MSCV based retroviruses encoding different point mutations in the Aurora B ATP binding site, which should lead to resistance against AS703569. By this strategy we were able to identify an AS703569 resistant mutant (Aurora B G216V). This mutant shows significant resistance in vitro and is able to augment the antiproliferative capacity of AS703569 in Bcr-Abl positive cells. Taken together, our data demonstrate that anti-proliferative effects of AS703569 in Bcr-Abl positive cells are primarily mediated by functional inhibition of Aurora kinases, especially of Aurora kinase B. Since Aurora kinases are clearly implicated in tumorgenesis, they will become a high potential therapeutic target for anticancer therapy. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Inhibition of the aurora kinases suppresses in vitro NT2-D1 cell growth and tumorigenicity

2009 ◽  
Vol 204 (2) ◽  
pp. 135-142 ◽  
Author(s):  
Salvatore Ulisse ◽  
Yannick Arlot-Bonnemains ◽  
Enke Baldini ◽  
Stefania Morrone ◽  
Silvia Carocci ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Cell Transformation ◽  
Germ Cell Tumors ◽  
Aurora Kinase ◽  
Malignant Cell ◽  
Dependent Manner ◽  
Testicular Germ Cell ◽  
Aurora Kinases

The aurora kinase family members, Aurora-A, -B, and -C (listed as AURKA, AURKB and AURKC respectively in the HUGO Database), are serine/threonine kinases involved in the regulation of chromosome segregation and cytokinesis, and alterations in their expression are associated with malignant cell transformation and genomic instability. Deregulation of the expression of the aurora kinases has been shown to occur also in testicular germ cell tumors (TGCTs) identifying them as putative anticancer therapeutic targets. We here evaluated the in vitro effects of MK-0457, an aurora kinases inhibitor, on cell proliferation, cell cycle, ploidy, apoptosis, and tumorigenicity on the TGCT-derived cell line NT2-D1. Treatment with MK-0457 inhibited cell proliferation in a time- and dose-dependent manner, with IC50=17.2±3.3 nM. MK-0457 did not affect the expression of the three aurora kinases, but prevented their ability to phosphorylate substrates relevant to the mitotic progression. Time-lapse experiments demonstrated that MK-0457-treated cells entered mitosis but were unable to complete it, presenting after short time the typical features of apoptotic cells. Cytofluorimetric analysis confirmed that the treatment with MK-0457 for 6 h induced NT2-D1 cells accumulation in the G2/M phase of the cell cycle and the subsequent appearance of sub-G0 nuclei. The latter result was further supported by the detection of caspase-3 activation following 24-h treatment with the inhibitor. Finally, MK-0457 prevented the capability of the NT2-D1 cells to form colonies in soft agar. In conclusion, the above findings demonstrate that inhibition of aurora kinase activity is effective in reducing in vitro growth and tumorigenicity of NT2-D1 cells, and indicate its potential therapeutic value for TGCT treatment.

Characterization of ScAP-23, a new cell line from murine subcutaneous adipose tissue, identifies genes for the molecular definition of preadipocytes

2007 ◽  
Vol 31 (2) ◽  
pp. 328-342 ◽  
Author(s):  
Ji Young Kim ◽  
Yu Wu ◽  
Cynthia M. Smas
Keyword(s):  
Adipose Tissue ◽  
Aurora Kinase ◽  
Dna Arrays ◽  
Aurora Kinase B ◽  
Chemokine Ligand ◽  
Embryonic Origin ◽  
Gene Expression Studies ◽  
Definition Of ◽  
Subcutaneous Adipose

The 3T3-L1 model of in vitro adipogenesis has provided key insights into the molecular nature of this process. However, given that 3T3-L1 are of an embryonic origin, it is not clear to what extent they represent adipogenesis as it occurs in white adipose tissue (WAT). With the goal of better defining preadipocytes and adipogenesis in WAT, we have generated a new cell culture model from adipocyte precursors present in C57BL/6 mouse subcutaneous WAT. ScAP-23 preadipocytes show fibroblastic morphology, and on treatment with dexamethasone, 3-methylisobutylxanthine, insulin, and indomethacin, convert to nearly 100% adipocyte morphology. ScAP-23 adipocytes contain abundant lipid droplets and express transcripts for PPARγ, C/EBP family, and SREBP-1c transcription factors, SCD1, aFABP, ATGL, GLUT4, FAS, LDL, and GPDH, and are insulin responsive. Differential screening of 1,176 genes using nylon DNA arrays identified 10 transcripts enriched in ScAP-23 adipocytes vs. preadipocytes and 26 transcripts enriched in ScAP-23 preadipocytes vs. adipocytes. Semiquantitative or real-time PCR analyses identified a common cohort of 14 transcripts markedly downregulated in both ScAP-23 and 3T3-L1 adipogenesis. These included catenin-β1, chemokine ligand-2, serine or cysteine peptidase inhibitor f1, aurora kinase B, thrombospondin2, and solute carrier-7a5. Five of these transcripts (Ccl2, Serpinf1, Aurkb, Thbs2, and Slc7a5) demonstrated at least a twofold increase in WAT from obese ( ob/ob) mice compared with that of wild-type mice. This suggests that comparative gene expression studies of ScAP-23 and 3T3-L1 adipogenesis may be particularly fruitful in identifying preadipocyte-expressed genes that play a role in adipose tissue physiology and/or pathophysiology.

Molecular characterization of neuroendocrine prostate cancer (NEPC) and identification of new drug targets.

2011 ◽  
Vol 29 (7_suppl) ◽  
pp. 19-19 ◽  
Author(s):  
H. Beltran ◽  
D. Rickman ◽  
K. Park ◽  
A. Sboner ◽  
T. Macdonald ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Drug Targets ◽  
Kinase Activity ◽  
Aurora Kinase ◽  
Large Cohort ◽  
Small Subset ◽  
Aurora Kinases ◽  
New Drug

19 Background: NEPC is an aggressive variant of prostate cancer that can arise de novo or from existing prostate adenocarcinoma (PCA). We sought to better understand the molecular transformation of NEPC and identify new drug targets. Methods: We used Next Generation RNA sequencing and oligonucleotide arrays to profile 7 NEPC, 30 PCA, 5 benign prostate (BEN), and validated findings on tumors from a large cohort of patients (30 NEPC, 118 PCA, 30 BEN) using IHC and FISH. Functional studies were performed using NCI-H660 (NEPC), VCaP and LnCaP (PCA), RWPE (BEN). Results: ERG rearrangement was present in 47% of NEPC, but ERG protein expression was absent and corresponded directly with lack of AR expression. 936/25932 genes were differentially expressed in NEPC versus PCA (P<0.001). Aurora kinases (AURKA, AURKB) and N-myc (MYCN) were overexpressed in NEPC (P<0.001) and AURKA and MYCN amplified. Using IHC and FISH, we validated these findings on a large cohort and found majority (>80%) of NEPC showed Aurora overexpression, 35% had AURKA and MYCN amplification. A small subset of PCA (5%) and no BEN were positive. Transfection of MYCN induced AURKA expression and kinase activity in vitro, and MYCN or AURKA could induce expression of neuroendocrine (NE) markers (SYP, NSE). After validating NCI-H660 as model of NEPC, we observed dramatic and enhanced in vitro and in vivo sensitivity to the Aurora kinase inhibitor PHA-739358 in NCI-H660 compared to minimal to no effect in LnCaP and VCaP. Phospho-H3 expression, a downstream marker of Aurora kinase activity, was inhibited in the treated NCI-H660 and not in PCA. Notably, NE marker expression was also suppressed in the treated NCI-H660 xenografts, again supporting a role of Aurora kinase in modulating the NE phenotype. Conclusions: There is likely clonal origin of NEPC from PCA (with ERG fusion positivity seen in both), but ERG expression is limited to PCA and driven by AR signaling. We discovered significant overexpression and gene amplification of Aurora kinases and N-myc in NEPC and a small subset of PCA, and evidence that that they cooperate and induce a NE phenotype in prostate cells. In vitro and in vivo data confirms that these are novel drug targets for NEPC. No significant financial relationships to disclose.

scholarly journals Inhibition of Aurora Kinase B Is Important for Biologic Activity of the Dual Inhibitors of BCR-ABL and Aurora Kinases R763/AS703569 and PHA-739358 in BCR-ABL Transformed Cells

PLoS ONE ◽  
2014 ◽  
Vol 9 (11) ◽  
pp. e112318 ◽  
Author(s):  
Anna L. Illert ◽  
Anna K. Seitz ◽  
Christoph Rummelt ◽  
Stefanie Kreutmair ◽  
Richard A. Engh ◽  
...  
Keyword(s):  
Aurora Kinase ◽  
Transformed Cells ◽  
Aurora Kinases ◽  
Aurora Kinase B ◽  
Biologic Activity ◽  
Dual Inhibitors

The Relevance of Aurora Kinase Inhibition in Hematological Malignancies

2021 ◽  
Vol 1 (3) ◽  
pp. 111-126
Author(s):  
CAIO BEZERRA MACHADO ◽  
EMERSON LUCENA DA SILVA ◽  
BEATRIZ MARIA DIAS NOGUEIRA ◽  
JEAN BRENO SILVEIRA DA SILVA ◽  
MANOEL ODORICO DE MORAES FILHO ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Hematological Malignancies ◽  
Kinase Inhibitors ◽  
Synergistic Effects ◽  
Aurora Kinase ◽  
Aurora Kinases ◽  
The Past ◽  
Oncologic Patients

Aurora kinases are a family of serine/threonine protein kinases that play a central role in eukaryotic cell division. Overexpression of aurora kinases in cancer and their role as major regulators of the cell cycle quickly inspired the idea that their inhibition might be a potential pathway when treating oncologic patients. Over the past couple of decades, the search for designing and testing of molecules capable of inhibiting aurora activities fueled many pre-clinical and clinical studies. In this study, data from the past 10 years of in vitro and in vivo investigations, as well as clinical trials, utilizing aurora kinase inhibitors as therapeutics for hematological malignancies were compiled and discussed, aiming to highlight potential uses of these inhibitors as a novel monotherapy model or alongside conventional chemotherapies. While there is still much to be elucidated, it is clear that these kinases play a key role in oncogenesis, and their manageable toxicity and potentially synergistic effects still render them a focus of interest for future investigations in combinatorial clinical trials

Interleukin-15 Is a Proto-Oncogene In Acute Large Granular Lymphocyte Leukemia

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 704-704
Author(s):  
Anjali Mishra ◽  
Shujun Liu ◽  
Gregory H Sams ◽  
Douglas P Curphey ◽  
Ramasamy Santhanam ◽  
...  
Keyword(s):  
Conflicts Of Interest ◽  
Aurora Kinase ◽  
Normal Donor ◽  
Dna Hypermethylation ◽  
Leukemic Transformation ◽  
Aurora Kinase B ◽  
Repressor Complex

Abstract Abstract 704 Interleukin (IL)-15 is critical for the differentiation, proliferation, activation and survival of large granular lymphocytes (LGL). Malignant blasts from patients with acute LGL leukemia (LGLL) can express membrane bound IL-15 and often require IL-15 or IL-2 to survive and expand in vitro, suggesting a pivotal role of IL-15 in the genesis of LGLL in vivo. Indeed, 30% of mice engineered to over express IL-15 develop LGLL (J Exp Med 193:219-231, 2001), suggesting that IL-15 is a proto-oncogene. The present study examined the mechanism by which this may occur in mouse and in man. We observed ~2.5-fold increased levels of DNA methyltransferase 3b (Dnmt3b) in IL-15tg mice with LGLL compared to wild type (Wt) splenocytes (2.6 ± 0.6 -fold higher, N = 3 each, P =.03) and a ~2-fold increased levels of global DNA methylation (GDM) compared to Wt splenocytes (% global DNA levels measured by mass spec as % 5mC/(5mC+2dC): 3.6 ± 0.11%, N = 4 for IL-15tg LGLL; 1.5 ± 0.08%, N = 4 for Wt, P <.0001). Remarkably, samples from three LGLL patients exhibited significantly increased levels of DNMT3B when compared to their normal donor counterparts, ranging from 38-fold to 5448-fold (P <0.008), and a significant increase in GDM (4.4% ± 0.01 N = 3 for LGLL patients; 4.2 ± 0.01% N = 3 for normal donors, P =.008). Dnmt3b is negatively regulated by miR-29b, which is under the regulation of Myc (Nature Genetics 40:43-50, 2008). Blasts from both IL-15tg LGLL mice and LGLL patients had a significant decrease in miR-29b expression when compared to their Wt LGL and normal donor counterparts respectively (2-fold lower in mouse, P <.02; 11 to 230-fold lower in human samples, N = 3 each, P <.0009). This was accompanied by increased expression of Myc in LGLL samples (mouse LGLL: Wt LGL = 10.4 ± 1.3-fold higher, N = 3 each, P < 0.005; human LGLL: normal donor LGL = 7.7 ± 1.6 -fold higher, N = 4, P <.0015). Since IL-15 signaling appears important in development of LGLL we investigated the oncogenic effect of IL-15 by culturing sorted mouse Wt (NK1.1+) LGLs in medium supplemented with 10% FCS and 100 ng/ml IL-15. Within 12 hours of culture, these IL-15–stimulated Wt LGLs displayed 2.0 ± 0.5-fold lower levels of miR-29b due to increased binding of a repressor complex that included Myc in addition to NFkBp65 and Hdac1 at the miR-29b promoter (Fig. 1A). By day 30 of Wt LGL culture in IL-15, we observed a 2.6 ± 0.6-fold mRNA increase in Dnmt3b (N=3, P=.03) and a 10.4 ± 1.3-fold increase in Myc (N = 3, P < .005) compared to fresh Wt LGL, also confirmed at the protein level (Fig. 1B, green color). Compared to fresh Wt LGLs, day 30 IL-15-stimulated Wt LGLs exhibited a significant increase in GDM measured by mass spectrometry (%GDM: 2.5 ± 0.3 in stimulated Wt LGLs, N = 4, vs 1.5 ± 0.08 in non-stimulated Wt LGLs, N = 4, P <.01). Over several months, the IL-15-stimulated Wt LGLs continued to expand and accumulate centrosome aberrations and aneuploidy, with over expression of Aurora kinase B when compared to fresh Wt LGLs (170.5 ± 58.23 -fold higher, N = 3, P = .02). SCID mice injected with these transformed cells died of LGLL in the absence of exogenous IL-15. Thus, chronic in vitro exposure of Wt LGLs to excessive IL-15 results in leukemic transformation via a process that likely includes decreased miR-29b, increased Dnmt3b, global DNA hypermethylation, centrosome aberrations and chromosomal instability. To address the in vivo role of DNMT3B in IL-15-mediated leukemogenesis, we created DNMT3Btg mice under a vav-1 promoter. DNMT3Btg mice had normal survival at 2 years, while IL-15/DNMT3Btg mice showed a significantly lower latency and higher incidence of LGLL compared with IL-15tg mice (median survival: 20.7 wk in IL-15/DNMT3Btg vs 31.1 wk in IL-15tg, P <.0001; Fig. 2). Thirty-one of 42 (73%) IL-15/DNMT3Btg mice died of LGLL compared to 8 of 38 (21%) IL-15tg mice. Leukemic blasts from LGLL mice demonstrated excessive expression of Aurora kinase B over Wt splenocytes (257.7 ± 39.4 -fold higher, N = 3 each, P = .01) and aneuploidy. Collectively, we provide evidence that IL-15 is a proto-oncogene: excessive expression of this lymphocytotropic cytokine results in activation of a repressor complex that decreases expression of miR-29b, induces Dnmt3b expression, global DNA hypermethylation, aberrant centrosome formation, aneuploidy and leukemic transformation. We provide evidence for these mechanisms in both in vitro and in vivo mouse models as well as in primary LGLL patient samples. Disclosures: No relevant conflicts of interest to declare.

scholarly journals DNA Damage-Induced Acetylation of Lysine 3016 of ATM Activates ATM Kinase Activity

2007 ◽  
Vol 27 (24) ◽  
pp. 8502-8509 ◽  
Author(s):  
Yingli Sun ◽  
Ye Xu ◽  
Kanaklata Roy ◽  
Brendan D. Price
Keyword(s):  
Dna Damage ◽  
Kinase Activity ◽  
Histone Acetyltransferase ◽  
Kinase Domain ◽  
Atm Kinase ◽  
Lysine Residues ◽  
Atm Protein ◽  
Fatc Domain

ABSTRACT The ATM protein kinase is essential for cells to repair and survive genotoxic events. The activation of ATM's kinase activity involves acetylation of ATM by the Tip60 histone acetyltransferase. In this study, systematic mutagenesis of lysine residues was used to identify regulatory ATM acetylation sites. The results identify a single acetylation site at lysine 3016, which is located in the highly conserved C-terminal FATC domain adjacent to the kinase domain. Antibodies specific for acetyl-lysine 3016 demonstrate rapid (within 5 min) in vivo acetylation of ATM following exposure to bleomycin. Furthermore, lysine 3016 of ATM is a substrate in vitro for the Tip60 histone acetyltransferase. Mutation of lysine 3016 does not affect unstimulated ATM kinase activity but does abolish upregulation of ATM's kinase activity by DNA damage, inhibits the conversion of inactive ATM dimers to active ATM monomers, and prevents the ATM-dependent phosphorylation of the p53 and chk2 proteins. These results are consistent with a model in which acetylation of lysine 3016 in the FATC domain of ATM activates the kinase activity of ATM. The acetylation of ATM on lysine 3016 by Tip60 is therefore a key step linking the detection of DNA damage and the activation of ATM kinase activity.

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