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1.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38279262

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is the most aggressive type of pancreatic cancer, which rapidly develops resistance to the current standard of care. Several oncolytic Human AdenoViruses (HAdVs) have been reported to re-sensitize drug-resistant cancer cells and in combination with chemotherapeutics attenuate solid tumour growth. Obstacles preventing greater clinical success are rapid hepatic elimination and limited viral replication and spread within the tumour microenvironment. We hypothesised that higher intratumoural levels of the virus could be achieved by altering cellular epigenetic regulation. Here we report on the screening of an enriched epigenetics small molecule library and validation of six compounds that increased viral gene expression and replication. The greatest effects were observed with three epigenetic inhibitors targeting bromodomain (BRD)-containing proteins. Specifically, BRD4 inhibitors enhanced the efficacy of Ad5 wild type, Ad∆∆, and Ad-3∆-A20T in 3-dimensional co-culture models of PDAC and in vivo xenografts. RNAseq analysis demonstrated that the inhibitors increased viral E1A expression, altered expression of cell cycle regulators and inflammatory factors, and attenuated expression levels of tumour cell oncogenes such as c-Myc and Myb. The data suggest that the tumour-selective Ad∆∆ and Ad-3∆-A20T combined with epigenetic inhibitors is a novel strategy for the treatment of PDAC by eliminating both cancer and associated stromal cells to pave the way for immune cell access even after systemic delivery of the virus.


Assuntos
Carcinoma Ductal Pancreático , Terapia Viral Oncolítica , Vírus Oncolíticos , Neoplasias Pancreáticas , Humanos , Proteínas Nucleares/genética , Epigênese Genética , Vírus Oncolíticos/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Linhagem Celular Tumoral , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/terapia , Carcinoma Ductal Pancreático/patologia , Terapia Viral Oncolítica/métodos , Adenoviridae/genética , Microambiente Tumoral , Proteínas que Contêm Bromodomínio , Proteínas de Ciclo Celular/metabolismo
2.
Br J Cancer ; 125(7): 966-974, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34446858

RESUMO

BACKGROUND: Activating mutations in the Fms-like tyrosine kinase 3 (FLT3) are among the most prevalent oncogenic mutations in acute myeloid leukaemia. Inhibitors selectively targeting FLT3 kinase have shown promising clinical activity; their success in the clinic, however, has been limited due to the emergence of acquired resistance. METHODS: CCT245718 was identified and characterised as a dual Aurora A/FLT3 inhibitor through cell-based and biochemical assays. The ability of CCT245718 to overcome TKD-mediated resistance was evaluated in a cell line-based model of drug resistance to FLT3 inhibitors. RESULTS: CCT245718 exhibits potent antiproliferative activity towards FLT3-ITD + AML cell lines and strongly binds to FLT3-ITD and TKD (D835Y) mutants in vitro. Activities of both FLT3-ITD and Aurora A are also inhibited in cells. Inhibition of FLT3 results in reduced phosphorylation of STAT5, downregulation of survivin and induction of apoptotic cell death. Moreover, CCT245718 overcomes TKD-mediated resistance in a MOLM-13-derived cell line containing FLT3 with both ITD and D835Y mutations. It also inhibits FLT3 signalling in both parental and resistant cell lines compared to FLT3-specific inhibitor MLN518, which is only active in the parental cell line. CONCLUSIONS: Our results demonstrate that CCT245718 is a potent dual FLT3/Aurora A inhibitor that can overcome TKD-mediated acquired resistance.


Assuntos
Aurora Quinase A/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Imidazóis/farmacologia , Leucemia Mieloide Aguda/enzimologia , Tirosina Quinase 3 Semelhante a fms/genética , Aurora Quinase A/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/química , Leucemia Mieloide Aguda/tratamento farmacológico , Mutação , Fosforilação , Proteínas Recombinantes/farmacologia , Fator de Transcrição STAT5/metabolismo , Survivina/metabolismo , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/química
3.
Br J Cancer ; 117(7): 954-964, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-28829765

RESUMO

BACKGROUND: F-box and WD40 repeat domain-containing 7 (FBXW7) is an E3 ubiquitin ligase involved in the ubiquitination and degradation of multiple oncogenic substrates. The tumour suppressor function is frequently lost in multiple cancers through genetic deletion and mutations in a broad range of tumours. Loss of FBXW7 functionality results in the stabilisation of multiple major oncoproteins, culminating in increased cellular proliferation and pro-survival pathways, cell cycle deregulation, chromosomal instability and altered metabolism. Currently, there is no therapy to specifically target FBXW7-deficient tumours. METHODS: We performed a siRNA kinome screen to identify synthetically lethal hits to FBXW7 deficiency. RESULTS: We identified and validated cyclin G-associated kinase (GAK) as a potential new therapeutic target. Combined loss of FBXW7 and GAK caused cell cycle defects, formation of multipolar mitoses and the induction of apoptosis. The synthetic lethal mechanism appears to be independent of clathrin-mediated receptor endocytosis function of GAK. CONCLUSIONS: These data suggest a putative therapeutic strategy for a large number of different types of human cancers with FBXW7 loss, many of which have a paucity of molecular abnormalities and treatment options.


Assuntos
Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/genética , Proteínas F-Box/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mitose/genética , Neoplasias/genética , Proteínas Serina-Treonina Quinases/genética , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Clatrina/antagonistas & inibidores , Proteína 7 com Repetições F-Box-WD , Humanos , Interferência de RNA , RNA Interferente Pequeno , Sulfonamidas/farmacologia , Mutações Sintéticas Letais , Tiazolidinas/farmacologia
4.
Br J Cancer ; 116(9): 1166-1176, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28334731

RESUMO

BACKGROUND: The main role of the cell cycle is to enable error-free DNA replication, chromosome segregation and cytokinesis. One of the best characterised checkpoint pathways is the spindle assembly checkpoint, which prevents anaphase onset until the appropriate attachment and tension across kinetochores is achieved. MPS1 kinase activity is essential for the activation of the spindle assembly checkpoint and has been shown to be deregulated in human tumours with chromosomal instability and aneuploidy. Therefore, MPS1 inhibition represents an attractive strategy to target cancers. METHODS: To evaluate CCT271850 cellular potency, two specific antibodies that recognise the activation sites of MPS1 were used and its antiproliferative activity was determined in 91 human cancer cell lines. DLD1 cells with induced GFP-MPS1 and HCT116 cells were used in in vivo studies to directly measure MPS1 inhibition and efficacy of CCT271850 treatment. RESULTS: CCT271850 selectively and potently inhibits MPS1 kinase activity in biochemical and cellular assays and in in vivo models. Mechanistically, tumour cells treated with CCT271850 acquire aberrant numbers of chromosomes and the majority of cells divide their chromosomes without proper alignment because of abrogation of the mitotic checkpoint, leading to cell death. We demonstrated a moderate level of efficacy of CCT271850 as a single agent in a human colorectal carcinoma xenograft model. CONCLUSIONS: CCT271850 is a potent, selective and orally bioavailable MPS1 kinase inhibitor. On the basis of in vivo pharmacodynamic vs efficacy relationships, we predict that more than 80% inhibition of MPS1 activity for at least 24 h is required to achieve tumour stasis or regression by CCT271850.


Assuntos
Proteínas de Ciclo Celular/genética , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/genética , Animais , Proteínas de Ciclo Celular/antagonistas & inibidores , Linhagem Celular Tumoral , Células HCT116 , Humanos , Camundongos , Neoplasias/genética , Neoplasias/patologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Int J Cancer ; 136(9): 2146-57, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25302833

RESUMO

Non-small cell lung cancer (NSCLC) is the main cause of cancer-related death worldwide and new therapeutic strategies are urgently needed. In this study, we have characterized a panel of NSC lung cancer cell lines for the expression of coiled-coil-domain containing 6 (CCDC6), a tumor suppressor gene involved in apoptosis and DNA damage response. We show that low CCDC6 protein levels are associated with a weak response to DNA damage and a low number of Rad51 positive foci. Moreover, CCDC6 deficient lung cancer cells show defects in DNA repair via homologous recombination. In accordance with its role in the DNA damage response, CCDC6 attenuation confers resistance to cisplatinum, the current treatment of choice for NSCLC, but sensitizes the cells to olaparib, a small molecule inhibitor of the repair enzymes PARP1/2. Remarkably, the combination of the two drugs is more effective than each agent individually, as demonstrated by a combination index <1. Finally, CCDC6 is expressed at low levels in about 30% of the NSCL tumors we analyzed by TMA immunostaining. The weak CCDC6 protein staining is significatively correlated with the presence of lymph node metastasis (p ≤ 0.02) and negatively correlated to the disease free survival (p ≤ 0.01) and the overall survival (p ≤ 0.05). Collectively, the data indicate that CCDC6 levels provide valuable insight for OS. CCDC6 could represent a predictive biomarker of resistance to conventional single mode therapy and yield insight on tumor sensitivity to PARP inhibitors in NSCLC.


Assuntos
Antineoplásicos/farmacologia , Proteínas do Citoesqueleto/deficiência , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Apoptose/efeitos dos fármacos , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Cisplatino/farmacologia , Proteínas do Citoesqueleto/genética , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/genética , Metástase Linfática/genética , Masculino , Pessoa de Meia-Idade , Ftalazinas , Piperazinas , Rad51 Recombinase/genética
6.
Bioorg Med Chem Lett ; 25(19): 4203-9, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26296477

RESUMO

Introduction of a 1-benzyl-1H-pyrazol-4-yl moiety at C7 of the imidazo[4,5-b]pyridine scaffold provided 7a which inhibited a range of kinases including Aurora-A. Modification of the benzyl group in 7a, and subsequent co-crystallisation of the resulting analogues with Aurora-A indicated distinct differences in binding mode dependent upon the pyrazole N-substituent. Compounds 7a and 14d interact with the P-loop whereas 14a and 14b engage with Thr217 in the post-hinge region. These crystallographic insights provide options for the design of compounds interacting with the DFG motif or with Thr217.


Assuntos
Aurora Quinases/antagonistas & inibidores , Aurora Quinases/química , Imidazóis/síntese química , Imidazóis/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/síntese química , Pirazóis/farmacologia , Piridinas/síntese química , Piridinas/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalização , Relação Dose-Resposta a Droga , Humanos , Imidazóis/química , Camundongos , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Estrutura Molecular , Pirazóis/química , Piridinas/química , Relação Estrutura-Atividade
7.
Bioorg Med Chem Lett ; 24(15): 3469-74, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24953599

RESUMO

The metal-dependent phosphatase PPM1D (WIP1) is an important oncogene in cancer, with over-expression of the protein being associated with significantly worse clinical outcomes. In this communication we describe the discovery and optimization of novel 2,4-bisarylthiazoles that phenocopy the knockdown of PPM1D, without inhibiting its phosphatase activity. These compounds cause growth inhibition at nanomolar concentrations, induce apoptosis, activate p53 and display impressive cell-line selectivity. The results demonstrate the potential for targeting phenotypes in drug discovery when tackling challenging targets or unknown mechanisms.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Fosfoproteínas Fosfatases/antagonistas & inibidores , Tiazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Descoberta de Drogas , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Fenótipo , Fosfoproteínas Fosfatases/metabolismo , Proteína Fosfatase 2C , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química , Proteína Supressora de Tumor p53/metabolismo
8.
Nat Genet ; 34(4): 403-12, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12881723

RESUMO

Linkage analysis and haplotype mapping in interspecific mouse crosses (Mus musculus x Mus spretus) identified the gene encoding Aurora2 (Stk6 in mouse and STK15 in human) as a candidate skin tumor susceptibility gene. The Stk6 allele inherited from the susceptible M. musculus parent was overexpressed in normal cells and preferentially amplified in tumor cells from F(1) hybrid mice. We identified a common genetic variant in STK15 (resulting in the amino acid substitution F31I) that is preferentially amplified and associated with the degree of aneuploidy in human colon tumors. The Ile31 variant transforms rat1 cells more potently than the more common Phe31 variant. The E2 ubiquitin-conjugating enzyme UBE2N was a preferential binding partner of the 'weak' STK15 Phe31 variant form in yeast two-hybrid screens and in human cells. This interaction results in colocalization of UBE2N with STK15 at the centrosomes during mitosis. These results are consistent with an important role for the Ile31 variant of STK15 in human cancer susceptibility.


Assuntos
Oncogenes , Proteínas Serina-Treonina Quinases/genética , Enzimas de Conjugação de Ubiquitina , Aneuploidia , Animais , Aurora Quinase A , Aurora Quinases , Divisão Celular/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 20/genética , Cruzamentos Genéticos , Amplificação de Genes , Variação Genética , Haplótipos , Humanos , Técnicas In Vitro , Ligases/genética , Ligases/metabolismo , Camundongos , Camundongos Endogâmicos , Muridae , Mapeamento Físico do Cromossomo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Neoplasias Cutâneas/genética , Técnicas do Sistema de Duplo-Híbrido
9.
J Med Chem ; 66(4): 2622-2645, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36749938

RESUMO

The existence of multiple centrosomes in some cancer cells can lead to cell death through the formation of multipolar mitotic spindles and consequent aberrant cell division. Many cancer cells rely on HSET (KIFC1) to cluster the extra centrosomes into two groups to mimic the bipolar spindle formation of non-centrosome-amplified cells and ensure their survival. Here, we report the discovery of a novel 2-(3-benzamidopropanamido)thiazole-5-carboxylate with micromolar in vitro inhibition of HSET (KIFC1) through high-throughput screening and its progression to ATP-competitive compounds with nanomolar biochemical potency and high selectivity against the opposing mitotic kinesin Eg5. Induction of the multipolar phenotype was shown in centrosome-amplified human cancer cells treated with these inhibitors. In addition, a suitable linker position was identified to allow the synthesis of both fluorescent- and trans-cyclooctene (TCO)-tagged probes, which demonstrated direct compound binding to the HSET protein and confirmed target engagement in cells, through a click-chemistry approach.


Assuntos
Cinesinas , Tiazóis , Humanos , Linhagem Celular Tumoral , Centrossomo/metabolismo , Cinesinas/antagonistas & inibidores , Cinesinas/genética , Cinesinas/metabolismo , Mitose , Fuso Acromático/metabolismo , Tiazóis/química , Tiazóis/farmacologia
10.
J Biol Chem ; 284(48): 33177-84, 2009 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-19801554

RESUMO

Mutations in protein kinases can drive cancer through alterations of the kinase activity or by uncoupling kinase activity from regulation. Changes to protein expression in Aurora A, a mitotic Ser/Thr kinase, are associated with the development of several human cancers, but the effects of somatic cancer-associated mutations have not been determined. In this study we show that Aurora A kinase activity is altered in different ways in three somatic cancer-associated mutations located within the catalytic domain; Aurora A(V174M) shows constitutively increased kinase activity, Aurora A(S155R) activity is decreased primarily due to misregulation, and Aurora A(S361*) activity is ablated due to loss of structural integrity. These alterations suggest vastly different mechanisms for the role of these three mutations in human cancer. We have further characterized the Aurora A(S155R) mutant protein, found that its reduced cellular activity and mislocalization are due to loss of interaction with TPX2, and deciphered the structural basis of the disruption at 2.5 A resolution. Previous studies have shown that disruption of the Aurora A/TPX2 interaction results in defective spindles that generate chromosomal abnormalities. In a panel of 40 samples from microsatellite instability-positive colon cancer patients, we found one example in which the tumor contained only Aurora A(S155R), whereas the normal tissue contained only wild-type Aurora A. We propose that the S155R mutation is an example of a somatic mutation associated with this tumor type, albeit at modest frequency, that could promote aneuploidy through the loss of regulated interactions between Aurora A and its protein partners.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação , Neoplasias/enzimologia , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Aurora Quinases , Sequência de Bases , Domínio Catalítico/genética , Proteínas de Ciclo Celular/genética , Linhagem Celular , Cristalografia por Raios X , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Immunoblotting , Microscopia de Fluorescência , Proteínas Associadas aos Microtúbulos/genética , Modelos Moleculares , Neoplasias/patologia , Proteínas Nucleares/genética , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Estrutura Terciária de Proteína , Especificidade por Substrato , Transfecção
11.
Mod Pathol ; 23(10): 1334-45, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20543821

RESUMO

PPM1D (protein phosphatase magnesium-dependent 1δ) maps to the 17q23.2 amplicon and is amplified in ∼8% of breast cancers. The PPM1D gene encodes a serine threonine phosphatase, which is involved in the regulation of several tumour suppressor pathways, including the p53 pathway. Along with others, we have recently shown that PPM1D is one of the drivers of the 17q23.2 amplicon and a promising therapeutic target. Here we investigate whether PPM1D is overexpressed when amplified in breast cancers and the correlations between PPM1D overexpression and amplification with clinicopathological features and survival of breast cancer patients from a cohort of 245 patients with invasive breast cancer treated with therapeutic surgery followed by adjuvant anthracycline-based chemotherapy. mRNA was extracted from representative sections of tumours containing >50% of tumour cells and subjected to TaqMan quantitative real-time PCR using primers for PPM1D and for two housekeeping genes. PPM1D overexpression was defined as the top quartile of expression levels. Chromogenic in situ hybridization with in-house-generated probes for PPM1D was performed. Amplification was defined as >50% of cancer cells with >5 signals per nucleus/large gene clusters. PPM1D overexpression and amplification were found in 25 and 6% of breast cancers, respectively. All cases harbouring PPM1D amplification displayed PPM1D overexpression. PPM1D overexpression was inversely correlated with expression of TOP2A, EGFR and cytokeratins 5/6 and 17. PPM1D amplification was significantly associated with HER2 overexpression, and HER2, TOP2A and CCND1 amplification. No association between PPM1D gene amplification and PPM1D mRNA overexpression with survival was observed. In conclusion, PPM1D is consistently overexpressed when amplified; however, PPM1D overexpression is more pervasive than gene amplification. PPM1D overexpression and amplification are associated with tumours displaying luminal or HER2 phenotypes. Co-amplification of PPM1D and HER2/TOP2A and CCND1 are not random events and may suggest the presence of a 'firestorm' genetic profile.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Fosfoproteínas Fosfatases/genética , Neoplasias da Mama/mortalidade , Feminino , Amplificação de Genes , Humanos , Imuno-Histoquímica , Hibridização In Situ , Estimativa de Kaplan-Meier , Prognóstico , Proteína Fosfatase 2C , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise Serial de Tecidos
12.
Bioorg Med Chem Lett ; 20(20): 5988-93, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20833547

RESUMO

Co-crystallisation of the imidazo[1,2-a]pyrazine derivative 15 (3-chloro-N-(4-morpholinophenyl)-6-(pyridin-3-yl)imidazo[1,2-a]pyrazin-8-amine) with Aurora-A provided an insight into the interactions of this class of compound with Aurora kinases. This led to the design and synthesis of potent Aurora-A inhibitors demonstrating up to 70-fold selectivity in cell-based Aurora kinase pharmacodynamic biomarker assays.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirazinas/química , Pirazinas/farmacologia , Antineoplásicos/síntese química , Aurora Quinases , Linhagem Celular Tumoral , Cristalografia por Raios X , Humanos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/síntese química , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Pirazinas/síntese química , Relação Estrutura-Atividade
13.
Blood Adv ; 4(7): 1478-1491, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32282883

RESUMO

Internal tandem duplication of FLT3 (FLT3-ITD) is one of the most common somatic mutations in acute myeloid leukemia (AML); it causes constitutive activation of FLT3 kinase and is associated with high relapse rates and poor survival. Small-molecule inhibition of FLT3 represents an attractive therapeutic strategy for this subtype of AML, although resistance from secondary FLT3 tyrosine kinase domain (FLT3-TKD) mutations is an emerging clinical problem. CCT241736 is an orally bioavailable, selective, and potent dual inhibitor of FLT3 and Aurora kinases. FLT3-ITD+ cells with secondary FLT3-TKD mutations have high in vitro relative resistance to the FLT3 inhibitors quizartinib and sorafenib, but not to CCT241736. The mechanism of action of CCT241736 results in significant in vivo efficacy, with inhibition of tumor growth observed in efficacy studies in FLT3-ITD and FLT3-ITD-TKD human tumor xenograft models. The efficacy of CCT241736 was also confirmed in primary samples from AML patients, including those with quizartinib-resistant disease, which induces apoptosis through inhibition of both FLT3 and Aurora kinases. The unique combination of CCT241736 properties based on robust potency, dual selectivity, and significant in vivo activity indicate that CCT241736 is a bona fide clinical drug candidate for FLT3-ITD and TKD AML patients with resistance to current drugs.


Assuntos
Leucemia Mieloide Aguda , Compostos de Fenilureia , Aurora Quinases , Benzotiazóis , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/genética
14.
Cancer Res ; 67(4): 1689-95, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17308110

RESUMO

The Aurora-A/STK15 gene encodes a kinase that is frequently amplified in cancer. Overexpression of Aurora-A in mammalian cells leads to centrosome amplification, genetic instability, and transformation. In this study, we show that Aurora-A activates nuclear factor-kappaB (NF-kappaB) via IkappaBalpha phosphorylation. Inhibition of endogenous Aurora-A reduces tumor necrosis factor alpha (TNFalpha)-induced IkappaBalpha degradation. We analyzed primary human breast cancers, and 13.6% of samples showed Aurora-A gene amplification, all of which exhibited nuclear localization of NF-kappaB. We propose that this subgroup of patients with breast cancer might benefit from inhibiting Aurora-A. We also show that down-regulation of NF-kappaB via Aurora-A depletion can enhance cisplatin-dependent apoptosis. These data define a new role for Aurora-A in regulating IkappaBalpha that is critical for the activation of NF-kappaB-directed gene expression and may be partially responsible for the oncogenic effect of Aurora-A when the gene is amplified and overexpressed in human tumors.


Assuntos
Proteínas I-kappa B/metabolismo , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Antineoplásicos/farmacologia , Aurora Quinase A , Aurora Quinases , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Cisplatino/farmacologia , Regulação para Baixo , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Inibidor de NF-kappaB alfa , NF-kappa B/biossíntese , NF-kappa B/genética , Invasividade Neoplásica , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais
15.
Methods Mol Biol ; 1953: 33-42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30912014

RESUMO

Cellular models for siRNA and small molecule high-throughput screening have been widely used in the last decade to identify targets for drug discovery. As an example, we present a twofold readout approach based on cell viability and multipolar phenotype. To maximize the discovery of potential targets and at the same time reduce the number of false positives in our dataset, we have combined focused and rationally designed custom siRNA libraries with small molecule inhibitor libraries. Here we describe a cellular model for centrosome amplification as an example of how to design and perform a multiple readout/multiple screening strategy.


Assuntos
Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , RNA Interferente Pequeno/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Centrossomo/efeitos dos fármacos , Centrossomo/metabolismo , Biblioteca Gênica , Ensaios de Triagem em Larga Escala/métodos , Humanos , Interferência de RNA/efeitos dos fármacos
16.
Eur J Pharm Sci ; 139: 104899, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30953752

RESUMO

CCT241736 is a dual fms-like tyrosine kinase 3 (FLT3)/Aurora kinase inhibitor in development for the treatment of acute myeloid leukaemia. The successful development of any new drug relies on adequate safety testing including preclinical toxicology studies. Selection of an appropriate preclinical species requires a thorough understanding of the compound's metabolic clearance and pathways, as well as other pharmacokinetic and pharmacodynamic considerations. In addition, elucidation of the metabolising enzymes in human facilitates improved clinical prediction based on population pharmacokinetics and can inform drug-drug interaction studies. Intrinsic clearance (CLint) determination and metabolite profiling of CCT241736 in human and four preclinical species (dog, minipig, rat and mouse) was undertaken in cryopreserved hepatocytes and liver microsomes. Recombinant human cytochrome P450 bactosomes (rCYP) were utilised to provide reaction phenotyping data and support prediction of metabolic pathways. CCT241736 exhibited low CLint in both hepatocytes and liver microsomes of human, dog, minipig and rat, but considerably higher CLint in mouse. CYP3A4 and CYP3A5 were identified as the major enzymes responsible for biotransformation of CCT241736 in human, exclusively forming five out of seven metabolites. Minipig showed greatest similarity to human with regard to both overall metabolic profile and abundance of specific metabolites relative to parent compound, and is therefore proposed as the most appropriate toxicological species. The greatest disparity was observed between human and dog. Based on metabolic profile, either mouse or rat is a suitable rodent species for toxicology studies.


Assuntos
Aurora Quinases/antagonistas & inibidores , Piperazinas/farmacocinética , Inibidores de Proteínas Quinases/farmacocinética , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Cães , Avaliação Pré-Clínica de Medicamentos , Feminino , Hepatócitos/metabolismo , Humanos , Masculino , Camundongos Endogâmicos ICR , Microssomos Hepáticos/metabolismo , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Ratos Sprague-Dawley , Especificidade da Espécie , Suínos , Porco Miniatura , Testes de Toxicidade
17.
Mol Cancer Ther ; 18(10): 1696-1707, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31575759

RESUMO

BOS172722 (CCT289346) is a highly potent, selective, and orally bioavailable inhibitor of spindle assembly checkpoint kinase MPS1. BOS172722 treatment alone induces significant sensitization to death, particularly in highly proliferative triple-negative breast cancer (TNBC) cell lines with compromised spindle assembly checkpoint activity. BOS172722 synergizes with paclitaxel to induce gross chromosomal segregation defects caused by MPS1 inhibitor-mediated abrogation of the mitotic delay induced by paclitaxel treatment. In in vivo pharmacodynamic experiments, BOS172722 potently inhibits the spindle assembly checkpoint induced by paclitaxel in human tumor xenograft models of TNBC, as measured by inhibition of the phosphorylation of histone H3 and the phosphorylation of the MPS1 substrate, KNL1. This mechanistic synergy results in significant in vivo efficacy, with robust tumor regressions observed for the combination of BOS172722 and paclitaxel versus either agent alone in long-term efficacy studies in multiple human tumor xenograft TNBC models, including a patient-derived xenograft and a systemic metastasis model. The current target indication for BOS172722 is TNBC, based on their high sensitivity to MPS1 inhibition, the well-defined clinical patient population with high unmet need, and the synergy observed with paclitaxel.


Assuntos
Pontos de Checagem do Ciclo Celular , Pirimidinas/farmacologia , Fuso Acromático/metabolismo , Triazóis/farmacologia , Neoplasias de Mama Triplo Negativas/patologia , Animais , Disponibilidade Biológica , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Segregação de Cromossomos/efeitos dos fármacos , Cromossomos Humanos/genética , Sinergismo Farmacológico , Humanos , Camundongos , PTEN Fosfo-Hidrolase/metabolismo , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Pirimidinas/química , Fuso Acromático/efeitos dos fármacos , Triazóis/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
18.
Mol Cancer Ther ; 6(12 Pt 1): 3147-57, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18089709

RESUMO

The Aurora family of serine/threonine kinases is important for the regulation of centrosome maturation, chromosome segregation, and cytokinesis during mitosis. Overexpression of Aurora kinases in mammalian cells leads to genetic instability and transformation. Increased levels of Aurora kinases have also been linked to a broad range of human tumors. Here, we describe the properties of CCT129202, a representative of a structurally novel series of imidazopyridine small-molecule inhibitors of Aurora kinase activity. This compound showed high selectivity for the Aurora kinases over a panel of other kinases tested and inhibits proliferation in multiple cultured human tumor cell lines. CCT129202 causes the accumulation of human tumor cells with >or=4N DNA content, leading to apoptosis. CCT120202-treated human tumor cells showed a delay in mitosis, abrogation of nocodazole-induced mitotic arrest, and spindle defects. Growth of HCT116 xenografts in nude mice was inhibited after i.p. administration of CCT129202. We show that p21, the cyclin-dependent kinase inhibitor, is induced by CCT129202. Up-regulation of p21 by CCT129202 in HCT116 cells led to Rb hypophosphorylation and E2F inhibition, contributing to a decrease in thymidine kinase 1 transcription. This has facilitated the use of 3'-deoxy-3'[(18)F]fluorothymidine-positron emission tomography to measure noninvasively the biological activity of the Aurora kinase inhibitor CCT129202 in vivo.


Assuntos
Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Aurora Quinases , Linhagem Celular Tumoral , Regulação para Baixo , Inibidores Enzimáticos/farmacocinética , Ensaio de Imunoadsorção Enzimática , Feminino , Histonas/metabolismo , Humanos , Camundongos , Microscopia de Fluorescência , Mitose/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Proteína do Retinoblastoma/metabolismo , Proteína Supressora de Tumor p53/metabolismo
19.
Oncotarget ; 9(28): 19525-19542, 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29731963

RESUMO

Accurate chromosome segregation is dependent on the spindle assembly checkpoint (SAC). In current models, the key direct role of Aurora B in the SAC has been suggested to be to promote rapid kinetochore localisation of MPS1, allowing MPS1 to generate the checkpoint signal. However, Aurora B is also thought to play an indirect role in the SAC through the destabilisation of kinetochore-microtubule (KT-MT) attachments. Here, we demonstrate that Aurora B activity is not required for the kinetochore recruitment of the majority of SAC proteins. More importantly, we show that the primary role of Aurora B in the SAC is to prevent the premature removal of SAC proteins from the kinetochore, which is strictly dependent on KT-MT interactions. Moreover, in the presence of KT-MT interactions, Aurora B inhibition silences a persistent SAC induced by tethering MPS1 to the kinetochore. This explains the highly synergistic interaction between Aurora B and MPS1 inhibitors to override the SAC, which is lost when cells are pre-arrested in nocodazole. Furthermore, we show that Aurora B and MPS1 inhibitors synergistically kill a panel of breast and colon cancer cell lines, including cells that are otherwise insensitive to Aurora B inhibitors alone. These data demonstrate that the major role of Aurora B in SAC is to prevent the removal of SAC proteins from tensionless kinetochores, thus inhibiting premature SAC silencing, and highlights a therapeutic strategy through combination of Aurora B and MPS1 inhibitors.

20.
Nat Commun ; 9(1): 1044, 2018 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-29535384

RESUMO

Triple negative breast cancers (TNBCs) lack recurrent targetable driver mutations but demonstrate frequent copy number aberrations (CNAs). Here, we describe an integrative genomic and RNAi-based approach that identifies and validates gene addictions in TNBCs. CNAs and gene expression alterations are integrated and genes scored for pre-specified target features revealing 130 candidate genes. We test functional dependence on each of these genes using RNAi in breast cancer and non-malignant cells, validating malignant cell selective dependence upon 37 of 130 genes. Further analysis reveals a cluster of 13 TNBC addiction genes frequently co-upregulated that includes genes regulating cell cycle checkpoints, DNA damage response, and malignant cell selective mitotic genes. We validate the mechanism of addiction to a potential drug target: the mitotic kinesin family member C1 (KIFC1/HSET), essential for successful bipolar division of centrosome-amplified malignant cells and develop a potential selection biomarker to identify patients with tumors exhibiting centrosome amplification.


Assuntos
Genômica/métodos , Neoplasias de Mama Triplo Negativas/genética , Pontos de Checagem do Ciclo Celular/genética , Variações do Número de Cópias de DNA/genética , Dano ao DNA/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Inativação Gênica/fisiologia , Humanos , Cinesinas/genética , Interferência de RNA
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