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1.
Arch Dis Child ; 109(6): 497-502, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38627026

RESUMO

BACKGROUND: 3D printing has been used in different medical contexts, although it is underutilised in paediatrics. We present the first use of 3D printing in the management of three paediatric patients with complex renovascular disease. METHODS: Patient-specific 3D models were produced from conventional 2D imaging and manufactured using 3D polyjet printing technology. All three patients had different underlying pathologies, but all underwent multiple endovascular interventions (renal artery balloon angioplasty) prior to 3D printing and subsequent vascular surgery. The models were verified by an expert radiologist and then presented to the multidisciplinary team to aid with surgical planning. RESULTS: Following evaluation of the 3D-printed models, all patients underwent successful uni/bilateral renal auto-transplants and aortic bypass surgery. The 3D models allowed more detailed preoperative discussions and more focused planning of surgical approach, therefore enhancing safer surgical planning. It influenced clinical decision-making and shortened general anaesthetic time. The families and the patients reported that they had a significantly improved understanding of the patient's condition and had more confidence in understanding proposed surgical intervention, thereby contributing to obtaining good-quality informed consent. CONCLUSION: 3D printing has a great potential to improve both surgical safety and decision-making as well as patient understanding in the field of paediatrics and may be considered in wider surgical areas.


Assuntos
Impressão Tridimensional , Criança , Humanos , Angioplastia com Balão/métodos , Modelos Anatômicos , Obstrução da Artéria Renal/cirurgia , Obstrução da Artéria Renal/diagnóstico por imagem , Obstrução da Artéria Renal/terapia , Procedimentos Cirúrgicos Vasculares/métodos , Procedimentos Cirúrgicos Vasculares/instrumentação
2.
Sci Adv ; 10(12): eadl4018, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517966

RESUMO

In a phenotypical screen of 56 acute myeloid leukemia (AML) patient samples and using a library of 10,000 compounds, we identified a hit with increased sensitivity toward SF3B1-mutated and adverse risk AMLs. Through structure-activity relationship studies, this hit was optimized into a potent, specific, and nongenotoxic molecule called UM4118. We demonstrated that UM4118 acts as a copper ionophore that initiates a mitochondrial-based noncanonical form of cell death known as cuproptosis. CRISPR-Cas9 loss-of-function screen further revealed that iron-sulfur cluster (ISC) deficiency enhances copper-mediated cell death. Specifically, we found that loss of the mitochondrial ISC transporter ABCB7 is synthetic lethal to UM4118. ABCB7 is misspliced and down-regulated in SF3B1-mutated leukemia, creating a vulnerability to copper ionophores. Accordingly, ABCB7 overexpression partially rescued SF3B1-mutated cells to copper overload. Together, our work provides mechanistic insights that link ISC deficiency to cuproptosis, as exemplified by the high sensitivity of SF3B1-mutated AMLs. We thus propose SF3B1 mutations as a biomarker for future copper ionophore-based therapies.


Assuntos
Cobre , Leucemia Mieloide Aguda , Humanos , Cobre/metabolismo , Fatores de Processamento de RNA/genética , Mutação , Leucemia Mieloide Aguda/genética , Ionóforos/farmacologia , Fosfoproteínas/metabolismo
3.
J Clin Invest ; 132(10)2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35316215

RESUMO

Gastric carcinogenesis is mediated by complex interactions among Helicobacter pylori, host, and environmental factors. Here, we demonstrate that H. pylori augmented gastric injury in INS-GAS mice under iron-deficient conditions. Mechanistically, these phenotypes were not driven by alterations in the gastric microbiota; however, discovery-based and targeted metabolomics revealed that bile acids were significantly altered in H. pylori-infected mice with iron deficiency, with significant upregulation of deoxycholic acid (DCA), a carcinogenic bile acid. The severity of gastric injury was further augmented when H. pylori-infected mice were treated with DCA, and, in vitro, DCA increased translocation of the H. pylori oncoprotein CagA into host cells. Conversely, bile acid sequestration attenuated H. pylori-induced injury under conditions of iron deficiency. To translate these findings to human populations, we evaluated the association between bile acid sequestrant use and gastric cancer risk in a large human cohort. Among 416,885 individuals, a significant dose-dependent reduction in risk was associated with cumulative bile acid sequestrant use. Further, expression of the bile acid receptor transmembrane G protein-coupled bile acid receptor 5 (TGR5) paralleled the severity of carcinogenic lesions in humans. These data demonstrate that increased H. pylori-induced injury within the context of iron deficiency is tightly linked to altered bile acid metabolism, which may promote gastric carcinogenesis.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Deficiências de Ferro , Neoplasias Gástricas , Animais , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Ácidos e Sais Biliares/metabolismo , Carcinogênese/metabolismo , Mucosa Gástrica/metabolismo , Infecções por Helicobacter/complicações , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Humanos , Inflamação/patologia , Camundongos , Neoplasias Gástricas/genética
4.
Blood ; 137(5): 661-677, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33197925

RESUMO

A number of clinically validated drugs have been developed by repurposing the CUL4-DDB1-CRBN-RBX1 (CRL4CRBN) E3 ubiquitin ligase complex with molecular glue degraders to eliminate disease-driving proteins. Here, we present the identification of a first-in-class GSPT1-selective cereblon E3 ligase modulator, CC-90009. Biochemical, structural, and molecular characterization demonstrates that CC-90009 coopts the CRL4CRBN to selectively target GSPT1 for ubiquitination and proteasomal degradation. Depletion of GSPT1 by CC-90009 rapidly induces acute myeloid leukemia (AML) apoptosis, reducing leukemia engraftment and leukemia stem cells (LSCs) in large-scale primary patient xenografting of 35 independent AML samples, including those with adverse risk features. Using a genome-wide CRISPR-Cas9 screen for effectors of CC-90009 response, we uncovered the ILF2 and ILF3 heterodimeric complex as a novel regulator of cereblon expression. Knockout of ILF2/ILF3 decreases the production of full-length cereblon protein via modulating CRBN messenger RNA alternative splicing, leading to diminished response to CC-90009. The screen also revealed that the mTOR signaling and the integrated stress response specifically regulate the response to CC-90009 in contrast to other cereblon modulators. Hyperactivation of the mTOR pathway by inactivation of TSC1 and TSC2 protected against the growth inhibitory effect of CC-90009 by reducing CC-90009-induced binding of GSPT1 to cereblon and subsequent GSPT1 degradation. On the other hand, GSPT1 degradation promoted the activation of the GCN1/GCN2/ATF4 pathway and subsequent apoptosis in AML cells. Collectively, CC-90009 activity is mediated by multiple layers of signaling networks and pathways within AML blasts and LSCs, whose elucidation gives insight into further assessment of CC-90009s clinical utility. These trials were registered at www.clinicaltrials.gov as #NCT02848001 and #NCT04336982).


Assuntos
Acetamidas/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Isoindóis/farmacologia , Leucemia Mieloide Aguda/patologia , Terapia de Alvo Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Células-Tronco Neoplásicas/efeitos dos fármacos , Piperidonas/farmacologia , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Acetamidas/uso terapêutico , Animais , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Humanos , Isoindóis/uso terapêutico , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Moleculares , Células-Tronco Neoplásicas/enzimologia , Proteína do Fator Nuclear 45/fisiologia , Proteínas do Fator Nuclear 90/fisiologia , Fatores de Terminação de Peptídeos/metabolismo , Piperidonas/uso terapêutico , Complexo de Endopeptidases do Proteassoma/metabolismo , Conformação Proteica , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteólise , Bibliotecas de Moléculas Pequenas , Estresse Fisiológico , Serina-Treonina Quinases TOR/fisiologia , Células U937 , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
J Med Chem ; 63(13): 6648-6676, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32130004

RESUMO

Many patients with multiple myeloma (MM) initially respond to treatment with modern combination regimens including immunomodulatory agents (lenalidomide and pomalidomide) and proteasome inhibitors. However, some patients lack an initial response to therapy (i.e., are refractory), and although the mean survival of MM patients has more than doubled in recent years, most patients will eventually relapse. To address this need, we explored the potential of novel cereblon E3 ligase modulators (CELMoDs) for the treatment of patients with relapsed or refractory multiple myeloma (RRMM). We found that optimization beyond potency of degradation, including degradation efficiency and kinetics, could provide efficacy in a lenalidomide-resistant setting. Guided by both phenotypic and protein degradation data, we describe a series of CELMoDs for the treatment of RRMM, culminating in the discovery of CC-92480, a novel protein degrader and the first CELMoD to enter clinical development that was specifically designed for efficient and rapid protein degradation kinetics.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos/farmacologia , Mieloma Múltiplo/tratamento farmacológico , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Concentração Inibidora 50 , Camundongos , Mieloma Múltiplo/patologia , Recidiva , Estereoisomerismo , Falha de Tratamento , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Elife ; 72018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30234487

RESUMO

The cereblon modulating agents (CMs) including lenalidomide, pomalidomide and CC-220 repurpose the Cul4-RBX1-DDB1-CRBN (CRL4CRBN) E3 ubiquitin ligase complex to induce the degradation of specific neomorphic substrates via polyubiquitination in conjunction with E2 ubiquitin-conjugating enzymes, which have until now remained elusive. Here we show that the ubiquitin-conjugating enzymes UBE2G1 and UBE2D3 cooperatively promote the K48-linked polyubiquitination of CRL4CRBN neomorphic substrates via a sequential ubiquitination mechanism. Blockade of UBE2G1 diminishes the ubiquitination and degradation of neomorphic substrates, and consequent antitumor activities elicited by all tested CMs. For example, UBE2G1 inactivation significantly attenuated the degradation of myeloma survival factors IKZF1 and IKZF3 induced by lenalidomide and pomalidomide, hence conferring drug resistance. UBE2G1-deficient myeloma cells, however, remained sensitive to a more potent IKZF1/3 degrader CC-220. Collectively, it will be of fundamental interest to explore if loss of UBE2G1 activity is linked to clinical resistance to drugs that hijack the CRL4CRBN to eliminate disease-driving proteins.


Assuntos
Peptídeo Hidrolases/metabolismo , Proteólise , Enzimas de Conjugação de Ubiquitina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Linhagem Celular Tumoral , Células HEK293 , Humanos , Fator de Transcrição Ikaros/metabolismo , Especificidade por Substrato/efeitos dos fármacos , Talidomida/análogos & derivados , Talidomida/farmacologia , Enzimas de Conjugação de Ubiquitina/química , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
7.
J Med Chem ; 61(2): 535-542, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-28425720

RESUMO

The drugs lenalidomide and pomalidomide bind to the protein cereblon, directing the CRL4-CRBN E3 ligase toward the transcription factors Ikaros and Aiolos to cause their ubiquitination and degradation. Here we describe CC-220 (compound 6), a cereblon modulator in clinical development for systemic lupus erythematosis and relapsed/refractory multiple myeloma. Compound 6 binds cereblon with a higher affinity than lenalidomide or pomalidomide. Consistent with this, the cellular degradation of Ikaros and Aiolos is more potent and the extent of substrate depletion is greater. The crystal structure of cereblon in complex with DDB1 and compound 6 reveals that the increase in potency correlates with increased contacts between compound 6 and cereblon away from the modeled binding site for Ikaros/Aiolos. These results describe a new cereblon modulator which achieves greater substrate degradation via tighter binding to the cereblon E3 ligase and provides an example of the effect of E3 ligase binding affinity with relevance to other drug discovery efforts in targeted protein degradation.


Assuntos
Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Fator de Transcrição Ikaros/metabolismo , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Proteólise/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal , Linhagem Celular Tumoral , Cristalografia por Raios X , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Transferência Ressonante de Energia de Fluorescência , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/metabolismo , Humanos , Lenalidomida/química , Lenalidomida/metabolismo , Morfolinas , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Ftalimidas , Piperidonas , Ligação Proteica , Ubiquitina-Proteína Ligases
8.
Lancet Oncol ; 18(6): 755-769, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28479233

RESUMO

BACKGROUND: The tAnGo trial was designed to investigate the potential role of gemcitabine when added to anthracycline and taxane-containing adjuvant chemotherapy for early breast cancer. When this study was developed, gemcitabine had shown significant activity in metastatic breast cancer, and there was evidence of a favourable interaction with paclitaxel. METHODS: tAnGo was an international, open-label, randomised, phase 3 superiority trial that enrolled women aged 18 years or older with newly diagnosed, early-stage breast cancer who had a definite indication for chemotherapy, any nodal status, any hormone receptor status, Eastern Cooperative Oncology Group performance status of 0-1, and adequate bone marrow, hepatic, and renal function. Women were recruited from 127 clinical centres and hospitals in the UK and Ireland, and randomly assigned (1:1) to one of two treatment regimens: epirubicin, cyclophosphamide, and paclitaxel (four cycles of 90 mg/m2 intravenously administered epirubicin and 600 mg/m2 intravenously administered cyclophosphamide on day 1 every 3 weeks, followed by four cycles of 175 mg/m2 paclitaxel as a 3 h infusion on day 1 every 3 weeks) or epirubicin, cyclophosphamide, and paclitaxel plus gemcitabine (the same chemotherapy regimen as the other group, with the addition of 1250 mg/m2 gemcitabine to the paclitaxel cycles, administered intravenously as a 0·5 h infusion on days 1 and 8 every 3 weeks). Patients were randomly assigned by a central computerised deterministic minimisation procedure, with stratification by country, age, radiotherapy intent, nodal status, and oestrogen receptor and HER-2 status. The primary endpoint was disease-free survival and the trial aimed to detect 5% differences in 5-year disease-free survival between the treatment groups. Recruitment completed in 2004 and this is the final, intention-to-treat analysis. This trial is registered with EudraCT (2004-002927-41), ISRCTN (51146252), and ClinicalTrials.gov (NCT00039546). FINDINGS: Between Aug 22, 2001, and Nov 26, 2004, 3152 patients were enrolled and randomly assigned to epirubicin, cyclophosphamide, paclitaxel, and gemcitabine (gemcitabine group; n=1576) or to epirubicin, cyclophosphamide, and paclitaxel (control group; n=1576). 11 patients (six in the gemcitabine group and five in the control group) were ineligible because of pre-existing metastases and were therefore excluded from the analysis. At this protocol-specified final analysis (median follow-up 10 years [IQR 10-10]), 1087 disease-free survival events and 914 deaths had occurred. Disease-free survival did not differ significantly between the treatment groups at 10 years (65% [63-68] in the gemcitabine group vs 65% [62-67] in the control group), and median disease-free survival was not reached (adjusted hazard ratio 0·97 [95% CI 0·86-1·10], p=0·64). Toxicity, dose intensity, and a detailed safety substudy showed both regimens to be safe, deliverable, and tolerable. Grade 3 and 4 toxicities were reported at expected levels in both groups. The most common were neutropenia (527 [34%] of 1565 patients in the gemcitabine group vs 412 [26%] of 1567 in the control group), myalgia and arthralgia (207 [13%] vs 186 [12%]), fatigue (207 [13%] vs 152 [10%]), infection (202 [13%] vs 141 [9%]), vomiting (143 [9%] vs 108 [7%]), and nausea (132 [8%] vs 102 [7%]). INTERPRETATION: The addition of gemcitabine to anthracycline and taxane-based adjuvant chemotherapy at this dose and schedule confers no therapeutic advantage in terms of disease-free survival in early breast cancer, although it can cause increased toxicity. Therefore, gemcitabine has not been added to standard adjuvant chemotherapy in breast cancer for any subgroup. FUNDING: Cancer Research UK core funding for Clinical Trials Unit at the University of Birmingham, Eli Lilly, Bristol-Myers Squibb, and Pfizer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Análise de Intenção de Tratamento , Metástase Linfática , Mastectomia Segmentar , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Radioterapia , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Taxa de Sobrevida , Gencitabina
10.
Nature ; 535(7611): 252-7, 2016 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-27338790

RESUMO

Immunomodulatory drugs bind to cereblon (CRBN) to confer differentiated substrate specificity on the CRL4(CRBN) E3 ubiquitin ligase. Here we report the identification of a new cereblon modulator, CC-885, with potent anti-tumour activity. The anti-tumour activity of CC-885 is mediated through the cereblon-dependent ubiquitination and degradation of the translation termination factor GSPT1. Patient-derived acute myeloid leukaemia tumour cells exhibit high sensitivity to CC-885, indicating the clinical potential of this mechanism. Crystallographic studies of the CRBN-DDB1-CC-885-GSPT1 complex reveal that GSPT1 binds to cereblon through a surface turn containing a glycine residue at a key position, interacting with both CC-885 and a 'hotspot' on the cereblon surface. Although GSPT1 possesses no obvious structural, sequence or functional homology to previously known cereblon substrates, mutational analysis and modelling indicate that the cereblon substrate Ikaros uses a similar structural feature to bind cereblon, suggesting a common motif for substrate recruitment. These findings define a structural degron underlying cereblon 'neosubstrate' selectivity, and identify an anti-tumour target rendered druggable by cereblon modulation.


Assuntos
Antineoplásicos/farmacologia , Peptídeo Hidrolases/metabolismo , Fatores de Terminação de Peptídeos/metabolismo , Compostos de Fenilureia/farmacologia , Talidomida/análogos & derivados , Proteínas Adaptadoras de Transdução de Sinal , Motivos de Aminoácidos , Antineoplásicos/química , Sítios de Ligação , Cristalografia por Raios X , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Humanos , Fator de Transcrição Ikaros/química , Fator de Transcrição Ikaros/metabolismo , Modelos Moleculares , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Peptídeo Hidrolases/química , Fatores de Terminação de Peptídeos/química , Fatores de Terminação de Peptídeos/deficiência , Compostos de Fenilureia/química , Ligação Proteica , Proteólise/efeitos dos fármacos , Especificidade por Substrato , Talidomida/química , Talidomida/farmacologia , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/metabolismo
11.
Vet Parasitol ; 210(3-4): 167-78, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25936435

RESUMO

Macrocyclic lactone (ML) endectocides are used as chemoprophylaxis for heartworm infection (Dirofilaria immitis) in dogs and cats. Claims of loss of efficacy (LOE) of ML heartworm preventives have become common in some locations in the USA. We directly tested whether resistance to MLs exists in LOE isolates of D. immitis and identified genetic markers that are correlated with, and therefore can predict ML resistance. ML controlled studies showed that LOE strains of D. immitis established infections in dogs despite chemoprophylaxis with oral ivermectin or injectable moxidectin. A whole genome approach was used to search for loci associated with the resistance phenotype. Many loci showed highly significant differences between pools of susceptible and LOE D. immitis. Based on 186 potential marker loci, Sequenom(®) SNP frequency analyses were conducted on 663 individual parasites (adult worms and microfilariae) which were phenotypically characterized as susceptible (SUS), confirmed ML treatment survivors/resistant (RES), or suspected resistant/loss of efficacy (LOE) parasites. There was a subset of SNP loci which appears to be promising markers for predicting ML resistance, including SNPs in some genes that have been associated with ML resistance in other parasites. These data provide unequivocal proof of ML resistance in D. immitis and identify genetic markers that could be used to monitor for ML resistance in heartworms.


Assuntos
Dirofilaria immitis/genética , Dirofilariose/parasitologia , Doenças do Cão/parasitologia , Filaricidas/farmacologia , Lactonas/farmacologia , Animais , Quimioprevenção/veterinária , Dirofilaria immitis/efeitos dos fármacos , Cães , Resistência a Medicamentos , Feminino , Marcadores Genéticos/genética , Ivermectina/farmacologia , Macrolídeos/farmacologia , Masculino , Microfilárias , Polimorfismo de Nucleotídeo Único/genética
12.
Parasit Vectors ; 7: 494, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25376278

RESUMO

BACKGROUND: Strains of Dirofilaria immitis suspected of lack of efficacy (LOE) to macrocyclic lactone (ML) preventive drugs have been increasingly reported in dogs by practicing veterinarians since 2005 in the Lower Mississippi Delta region. If proven, and not controlled in the early stages, the emergence of ML drug resistance threatens to become a widespread problem in the US that may limit the effectiveness of current preventive drug treatment methods. METHODS: To validate practice reports, a statewide survey of Louisiana veterinarians was done to define the extent of the problem and identify focal 'hotspots' of reported ML LOEs using Geographic Information Systems (GIS) methods. The present study then utilized microfilariae (Mf) from two canine field cases from different state locations that fit criteria for a high index of suspicion of LOE against heartworms by ML drugs. Blood containing Mf from the canine field cases was used to infect and produce L3 in Aedes aegypti for experimental infection of two groups of dogs, each of which contained two laboratory dogs, one treated with prophylactic ivermectin (12 µg/kg) monthly for 6 months at twice the label dose (6 µg/kg), and one untreated control. RESULTS: Both treated and untreated dogs from Group I and Group II developed patent D. immitis infections by 218 DPI and 189 DPI, respectively, as evidenced by a positive occult heartworm antigen test and microfilaremia by the Knott's test. Mf counts gradually increased post-patency in test and control dogs. Infective larvae raised from microfilariae from the treated Group I dog were used to successfully establish a second generation isolate, confirming heritability of resistance in the face of a monthly ivermectin challenge dose of 24 µg/kg, given monthly for 3 months. CONCLUSIONS: These experimental infection studies provide in vivo evidence of the existence of ML drug resistance in dogs infected by D. immitis L3 from suspect field LOE cases in the Lower Mississippi Delta. Results encourage further work on mechanisms underlying the emergence of ML resistance in D. immitis and development of evidence-based resistance management strategies for heartworm preventives in order to extend the useful life of current drugs.


Assuntos
Anti-Helmínticos/farmacologia , Dirofilaria immitis/efeitos dos fármacos , Dirofilariose/parasitologia , Doenças do Cão/parasitologia , Resistência a Medicamentos , Ivermectina/farmacologia , Aedes , Animais , Anti-Helmínticos/administração & dosagem , Quimioprevenção/métodos , Dirofilaria immitis/isolamento & purificação , Dirofilariose/epidemiologia , Modelos Animais de Doenças , Cães , Humanos , Ivermectina/administração & dosagem , Louisiana/epidemiologia , Masculino , Mississippi
13.
Breast Cancer Res ; 15(5): R88, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24063698

RESUMO

INTRODUCTION: This Phase I study evaluated the safety, tolerability and efficacy of olaparib, a potent oral poly(ADPribose) polymerase (PARP) inhibitor, in combination with paclitaxel in patients with metastatic triple-negative breast cancer (mTNBC). METHODS: Eligible patients who had received ≤1 prior cytotoxic regimen for mTNBC were treated with olaparib 200 mg bid continuously plus weekly paclitaxel 90 mg/m2 for three weeks per four-week cycle. Dose modifications in a large proportion of patients due to neutropenia resulted in enrollment of a second cohort of patients who, if they experienced grade ≥2 neutropenia in cycle 1, received granulocyte-colony stimulating factor, which was continued prophylactically in subsequent cycles. All patients had measurable disease; tumor responses were evaluated according to RECIST (version 1.0). RESULTS: Nineteen patients (cohort 1, n = 9; cohort 2, n = 10) received treatment; 15 had received prior taxane chemotherapy. The most frequent adverse events were diarrhea (n = 12, 63%), nausea (n = 11, 58%) and neutropenia (n = 11, 58%). Seven neutropenia events were reported in cohort 1 (four grade ≥3) and four in cohort 2 (two grade ≥3, including one event of febrile neutropenia). The median (range) dose intensity of paclitaxel was 57% (26 to 100%) in cohort 1 and 73% (29 to 100%) in cohort 2. Seven patients (37%) had a confirmed partial response; one patient remains on olaparib monotherapy without progression. CONCLUSIONS: The combination of olaparib and weekly paclitaxel was complicated by a significant clinical interaction, with higher-than-expected rates of neutropenia despite secondary prophylaxis. Given the encouraging response rate, alternative scheduling and dosing strategies should be considered (funded by AstraZeneca; ClinicalTrials.gov, NCT00707707).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Paclitaxel/administração & dosagem , Ftalazinas/administração & dosagem , Piperazinas/administração & dosagem , Inibidores de Poli(ADP-Ribose) Polimerases , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/mortalidade
14.
Invest New Drugs ; 31(4): 949-58, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23315029

RESUMO

Olaparib (AZD2281) is an oral poly(ADP-ribose) polymerase (PARP) inhibitor with antitumour activity in cancer patients with BRCA1/2 germline mutations and in patients with homologous recombination deficiency. In this dose-finding study, patients were randomized to olaparib 10, 30, 100, 200 or 400 mg (capsule formulation) twice daily for the 4-5 days preceding breast cancer surgery. The primary objective was to identify an effective biological dose of olaparib for future trials. Secondary endpoints included evaluation of PARP-1 inhibition dose/exposure-response, and safety. Olaparib plasma pharmacokinetics (PK) and the pharmacodynamics (PD) in tumour and peripheral blood mononuclear cells (PBMCs) were evaluated. Population PK/PD modelling was performed on pooled data from this study and a previously reported study. Sixty patients were randomized (n = 12, each dose). Dose-dependent increases in exposure to olaparib were observed, but at ~50 % lower plasma exposure levels than seen in advanced disease studies. The mean maximal extent of PARP inhibition in PBMCs and tumour tissue was 50.6 % and 70.0 %, respectively, and was similar to inhibitory levels reported previously. No PARP inhibition-dose relationship was observed. Due to the unexpectedly low olaparib exposure, we were unable to determine an effective biological dose. Common adverse events included procedural pain (n = 31 patients), nausea, asthenia, malaise and increased blood creatinine (n = 6, each); these were of mild-to-moderate intensity, and all were manageable. Despite low olaparib exposure, PARP inhibition was consistent with previous reports. Reasons for the inter-study differences in exposure are unclear. The tolerability profile of olaparib was consistent with previous studies.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Procedimentos Cirúrgicos Eletivos , Inibidores Enzimáticos/farmacocinética , Ftalazinas/farmacologia , Ftalazinas/farmacocinética , Piperazinas/farmacologia , Piperazinas/farmacocinética , Inibidores de Poli(ADP-Ribose) Polimerases , Demografia , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Ftalazinas/sangue , Ftalazinas/uso terapêutico , Piperazinas/sangue , Piperazinas/uso terapêutico
15.
N Engl J Med ; 366(15): 1382-92, 2012 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-22452356

RESUMO

BACKGROUND: Olaparib (AZD2281) is an oral poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitor that has shown antitumor activity in patients with high-grade serous ovarian cancer with or without BRCA1 or BRCA2 germline mutations. METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 2 study to evaluate maintenance treatment with olaparib in patients with platinum-sensitive, relapsed, high-grade serous ovarian cancer who had received two or more platinum-based regimens and had had a partial or complete response to their most recent platinum-based regimen. Patients were randomly assigned to receive olaparib, at a dose of 400 mg twice daily, or placebo. The primary end point was progression-free survival according to the Response Evaluation Criteria in Solid Tumors guidelines. RESULTS: Of 265 patients who underwent randomization, 136 were assigned to the olaparib group and 129 to the placebo group. Progression-free survival was significantly longer with olaparib than with placebo (median, 8.4 months vs. 4.8 months from randomization on completion of chemotherapy; hazard ratio for progression or death, 0.35; 95% confidence interval [CI], 0.25 to 0.49; P<0.001). Subgroup analyses of progression-free survival showed that, regardless of subgroup, patients in the olaparib group had a lower risk of progression. Adverse events more commonly reported in the olaparib group than in the placebo group (by more than 10% of patients) were nausea (68% vs. 35%), fatigue (49% vs. 38%), vomiting (32% vs. 14%), and anemia (17% vs. 5%); the majority of adverse events were grade 1 or 2. An interim analysis of overall survival (38% maturity, meaning that 38% of the patients had died) showed no significant difference between groups (hazard ratio with olaparib, 0.94; 95% CI, 0.63 to 1.39; P=0.75). CONCLUSIONS: Olaparib as maintenance treatment significantly improved progression-free survival among patients with platinum-sensitive, relapsed, high-grade serous ovarian cancer. Interim analysis showed no overall survival benefit. The toxicity profile of olaparib in this population was consistent with that in previous studies. (Funded by AstraZeneca; ClinicalTrials.gov number, NCT00753545.).


Assuntos
Antineoplásicos/uso terapêutico , Quimioterapia de Manutenção , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Ftalazinas/uso terapêutico , Piperazinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Genes BRCA1 , Genes BRCA2 , Mutação em Linhagem Germinativa , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Ftalazinas/efeitos adversos , Piperazinas/efeitos adversos , Adulto Jovem
16.
Foot Ankle Surg ; 18(2): 124-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22444000

RESUMO

BACKGROUND: The mainstay of treatment for non-insertional Achilles tendinopathy is non-operative, however a proportion of patients will fail conservative measures. We describe the results of Achilles tendinoscopy with plantaris tendon release in patients who have failed first line conservative treatment for at least 6 months. METHODS: A consecutive series of 11 patients with a minimum of 2 years follow up. RESULTS: The mean AOFAS scores significantly improved from 68 pre-op to 92 post op (p=0.0002) as did the AOS scores for both pain (28% pre-op to 8% post op (p=0.0004)) and disability (38% pre-op to 10% post op (p=0.0005). The mean SF-36 scores also improved but were not statistically significant (pre-op 76, post op 87 (p=0.059). There were no complications. 8 of the 11 patients were satisfied, the other 3 somewhat satisfied. CONCLUSIONS: The results of Achilles tendinoscopy and division of the plantaris tendon are encouraging but further studies are required to compare it to other treatments. It is minimally invasive and low risk so should not affect the ability to perform a formal open procedure if unsuccessful.


Assuntos
Tendão do Calcâneo/cirurgia , Endoscopia , Tendinopatia/cirurgia , Tenotomia , Adulto , História do Século XXI , Humanos , Pessoa de Meia-Idade , Procedimentos Ortopédicos/métodos , Adulto Jovem
17.
Invest New Drugs ; 30(4): 1493-500, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21590367

RESUMO

BACKGROUND: The aim of this phase I study was to determine the safety and tolerability and to establish the maximum tolerated dose (MTD) of orally administered olaparib (AZD2281) in combination with topotecan in patients with advanced solid tumors. PATIENTS AND METHODS: Patients aged ≥ 18 years with histologically or cytologically diagnosed advanced solid tumors for whom no suitable effective therapy exists were included. Patients in four cohorts received topotecan (0.5 mg/m(2)/day × 3 days or 1.0 mg/m(2)/day × 3 days) intravenously in combination with oral olaparib 50, 100 or 200 mg bid for six cycles. The primary objectives were to determine the safety and tolerability and to establish the MTD of olaparib in combination with topotecan. RESULTS: Twenty-one patients were enrolled and 19 received treatment. Dose-limiting toxicities were neutropenia and thrombocytopenia. The MTD was established as topotecan 1.0 mg/m(2)/day × 3 days plus olaparib 100 mg bid. The most common adverse events (AEs) included fatigue and gastrointestinal events. There was an olaparib and topotecan dose-related increase in neutropenia which was dose limiting. CONCLUSIONS: Further development of olaparib and topotecan in combination was not explored due to dose-limiting hematological AEs and the resulting sub-therapeutic MTD.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Inibidores Enzimáticos/efeitos adversos , Neoplasias/tratamento farmacológico , Ftalazinas/efeitos adversos , Piperazinas/efeitos adversos , Inibidores de Poli(ADP-Ribose) Polimerases , Topotecan/uso terapêutico , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Estudos de Coortes , Demografia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Neoplasias/diagnóstico por imagem , Ftalazinas/administração & dosagem , Ftalazinas/farmacocinética , Ftalazinas/uso terapêutico , Piperazinas/administração & dosagem , Piperazinas/farmacocinética , Piperazinas/uso terapêutico , Poli(ADP-Ribose) Polimerases/metabolismo , Tomografia Computadorizada por Raios X , Topotecan/administração & dosagem , Topotecan/efeitos adversos , Topotecan/farmacocinética , Resultado do Tratamento
18.
J Clin Oncol ; 30(4): 372-9, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22203755

RESUMO

PURPOSE: Olaparib (AZD2281), an orally active poly (ADP-ribose) polymerase inhibitor that induces synthetic lethality in BRCA1- or BRCA2-deficient cells, has shown promising clinical efficacy in nonrandomized phase II trials in patients with ovarian cancer with BRCA1 or BRCA2 deficiency. We assessed the comparative efficacy and safety of olaparib and pegylated liposomal doxorubicin (PLD) in this patient population. PATIENTS AND METHODS: In this multicenter, open-label, randomized, phase II study, patients with ovarian cancer that recurred within 12 months of prior platinum therapy and with confirmed germline BRCA1 or BRCA2 mutations were enrolled. Patients were assigned in a 1:1:1 ratio to olaparib 200 mg twice per day or 400 mg twice per day continuously or PLD 50 mg/m(2) intravenously every 28 days. The primary efficacy end point was Response Evaluation Criteria in Solid Tumors (RECIST) -assessed progression-free survival (PFS). Secondary end points included objective response rate (ORR) and safety. RESULTS: Ninety-seven patients were randomly assigned. Median PFS was 6.5 months (95% CI, 5.5 to 10.1 months), 8.8 months (95% CI, 5.4 to 9.2 months), and 7.1 months (95% CI, 3.7 to 10.7 months) for the olaparib 200 mg, olaparib 400 mg, and PLD groups, respectively. There was no statistically significant difference in PFS (hazard ratio, 0.88; 95% CI, 0.51 to 1.56; P = .66) for combined olaparib doses versus PLD. RECIST-assessed ORRs were 25%, 31%, and 18% for olaparib 200 mg, olaparib 400 mg, and PLD, respectively; differences were not statistically significant. Tolerability of both treatments was as expected based on previous trials. CONCLUSION: The efficacy of olaparib was consistent with previous studies. However, the efficacy of PLD was greater than expected. Olaparib 400 mg twice per day is a suitable dose to explore in further studies in this patient population.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Genes BRCA1 , Genes BRCA2 , Mutação , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Doxorrubicina/análogos & derivados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Ftalazinas/administração & dosagem , Ftalazinas/efeitos adversos , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Estudos Prospectivos , Análise de Sobrevida
19.
Lancet Oncol ; 12(9): 852-61, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21862407

RESUMO

BACKGROUND: Olaparib (AZD2281) is a small-molecule, potent oral poly(ADP-ribose) polymerase (PARP) inhibitor. We aimed to assess the safety and tolerability of this drug in patients without BRCA1 or BRCA2 mutations with advanced triple-negative breast cancer or high-grade serous and/or undifferentiated ovarian cancer. METHODS: In this phase 2, multicentre, open-label, non-randomised study, women with advanced high-grade serous and/or undifferentiated ovarian carcinoma or triple-negative breast cancer were enrolled and received olaparib 400 mg twice a day. Patients were stratified according to whether they had a BRCA1 or BRCA2 mutation or not. The primary endpoint was objective response rate by Response Evaluation Criteria In Solid Tumors (RECIST). All patients who received treatment were included in the analysis of toxic effects, and patients who had measurable lesions at baseline were included in the primary efficacy analysis. This trial is registered at ClinicalTrials.gov, number NCT00679783. FINDINGS: 91 patients were enrolled (65 with ovarian cancer and 26 breast cancer) and 90 were treated between July 8, 2008, and Sept 24, 2009. In the ovarian cancer cohorts, 64 patients received treatment. 63 patients had target lesions and therefore were evaluable for objective response as per RECIST. In these patients, confirmed objective responses were seen in seven (41%; 95% CI 22-64) of 17 patients with BRCA1 or BRCA2 mutations and 11 (24%; 14-38) of 46 without mutations. No confirmed objective responses were reported in patients with breast cancer. The most common adverse events were fatigue (45 [70%] of patients with ovarian cancer, 13 [50%] of patients with breast cancer), nausea (42 [66%] and 16 [62%]), vomiting (25 [39%] and nine [35%]), and decreased appetite (23 [36%] and seven [27%]). INTERPRETATION: Our study suggests that olaparib is a promising treatment for women with ovarian cancer and further assessment of the drug in clinical trials is needed. FUNDING: AstraZeneca.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias da Mama/tratamento farmacológico , Carcinoma/tratamento farmacológico , Diferenciação Celular , Inibidores Enzimáticos/uso terapêutico , Recidiva Local de Neoplasia , Neoplasias Ovarianas/tratamento farmacológico , Ftalazinas/uso terapêutico , Piperazinas/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/química , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Canadá , Carcinoma/enzimologia , Carcinoma/genética , Carcinoma/mortalidade , Carcinoma/secundário , Intervalo Livre de Doença , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/efeitos adversos , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Mutação , Neoplasias Ovarianas/enzimologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Ftalazinas/administração & dosagem , Ftalazinas/efeitos adversos , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Poli(ADP-Ribose) Polimerases/metabolismo , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Fatores de Tempo , Resultado do Tratamento
20.
Cancer Chemother Pharmacol ; 68(6): 1485-95, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21487718

RESUMO

PURPOSE: We investigated whether the pharmacokinetics and tolerability of gefitinib were altered in patients with hepatic impairment due to cirrhosis or hepatic metastases in two open, parallel-group, multicenter studies. METHODS: In Study 1, subjects with normal hepatic function or mild, moderate, or severe hepatic impairment (Child-Pugh criteria) due to cirrhosis received single-dose gefitinib 250 mg (n = 10 per group). In Study 2, patients with solid malignant tumors with normal liver biochemistry (n = 18), moderate (n = 16), or severe (n = 7) hepatic impairment (liver biochemistry tests) due to metastases received gefitinib 250 mg daily for 28 days. RESULTS: In Study 1, the geometric mean area under the plasma concentration-time curve (AUC) for gefitinib was significantly higher in patients with hepatic impairment compared with healthy subjects; hepatic impairment was associated with reduced gefitinib plasma clearance, longer half-life, and reduced plasma metabolite levels. In Study 2, the geometric mean gefitinib steady-state AUC during the 24-h dosing interval was slightly, but not significantly, higher in patients with moderate hepatic impairment; there were, however, no significant differences between groups in gefitinib and metabolite pharmacokinetic parameters. In both studies, gefitinib was well tolerated across all cohorts. CONCLUSIONS: We conclude that the effect of hepatic impairment on gefitinib pharmacokinetics depends on the underlying etiology of that impairment and its classification.


Assuntos
Antineoplásicos/farmacocinética , Hepatopatias/metabolismo , Quinazolinas/farmacocinética , Adulto , Área Sob a Curva , Feminino , Gefitinibe , Humanos , Hepatopatias/etiologia , Masculino , Pessoa de Meia-Idade , Quinazolinas/efeitos adversos
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