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1.
Rev Sci Instrum ; 92(3): 033519, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33819987

RESUMO

The Opacity Platform on the National Ignition Facility (NIF) has been developed to measure iron opacities at varying densities and temperatures relevant to the solar interior and to verify recent experimental results obtained at the Sandia Z-machine, that diverge from theory. The first set of NIF experiments collected iron opacity data at ∼150 eV to 160 eV and an electron density of ∼7 × 1021 cm-3, with a goal to study temperatures up to ∼210 eV, with electron densities of up to ∼3 × 1022 cm-3. Among several techniques used to infer the temperature of the heated Fe sample, the absolutely calibrated DANTE-2 filtered diode array routinely provides measurements of the hohlraum conditions near the sample. However, the DANTE-2 temperatures are consistently low compared to pre-shot LASNEX simulations for a range of laser drive energies. We have re-evaluated the estimated uncertainty in the reported DANTE-2 temperatures and also the error generated by varying channel participation in the data analysis. An uncertainty of ±5% or better can be achieved with appropriate spectral coverage, channel participation, and metrology of the viewing slot.

2.
Vet J ; 258: 105450, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32564869

RESUMO

Cyclophosphamide is an alkylating agent used to treat cats with lymphoma, carcinomas and sarcomas. However, no clear consensus exists regarding the maximum tolerated dose (MTD) of oral cyclophosphamide in cats. Toxicities are rarely reported at published oral dosages of cyclophosphamide (200-300 mg/m2). The primary aim of this prospective study was to determine the MTD of oral cyclophosphamide in tumour-bearing cats via a modified phase I trial. A secondary aim was to define any toxicity. Forty-six client-owned tumour-bearing cats were enrolled. The cyclophosphamide dosage was escalated by approximately 10% (300, 330, 360, 400, 440, 460 and 480 mg/m2) in cohorts of at least six cats. The MTD of oral cyclophosphamide in this study was 460 mg/m2 with an inter-treatment interval of two to three weeks. Haematology is recommended 7 and 14 days after first cyclophosphamide treatment, and immediately before each subsequent dosage of cyclophosphamide or any potentially myelosuppressive chemotherapy agent. The dose-limiting toxicity was neutropenia with nadir at 7-21 days. This higher dosage was considered safe in combination with prednisolone and L-asparaginase. However, the higher dose of oral cyclophosphamide has not been evaluated in combination with other chemotherapy agents and thus should not be administered with these agents.


Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Doenças do Gato/tratamento farmacológico , Ciclofosfamida/administração & dosagem , Dose Máxima Tolerável , Neoplasias/veterinária , Administração Oral , Animais , Antineoplásicos Alquilantes/toxicidade , Gatos , Ciclofosfamida/toxicidade , Neoplasias/tratamento farmacológico , Estudos Prospectivos
3.
Aust Vet J ; 98(5): 181-184, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31971262

RESUMO

BACKGROUND: A fifteen-year old, female spayed domestic longhaired cat was presented for a routine vaccination during which an incidental abdominal mass was palpated. After further inquiry, occasional vomiting was reported to occur once every few weeks to months, associated with no other gastrointestinal signs. CASE REPORT: Ultrasonography revealed a gastric mass. Histopathology and immunohistochemistry confirmed a CD117 positive, smooth muscle actin and desmin negative neoplasm, consistent with a gastrointestinal stromal cell tumour (GIST). Treatment was initiated with toceranib phosphate resulting in stable disease for over eighteen months, and the patient was still alive at the time of writing. CONCLUSION: GISTs are rare in cats and this is the first report of medical management of feline GIST using toceranib.


Assuntos
Tumores do Estroma Gastrointestinal/veterinária , Pirróis , Animais , Doenças do Gato , Gatos , Feminino , Indóis , Células Estromais
4.
Vet J ; 242: 39-43, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30503542

RESUMO

Cyclophosphamide is an alkylating agent used as chemotherapy for cats with lymphoma, carcinomas and sarcomas. Clinical and pharmacokinetic studies of cyclophosphamide in normal and tumor-bearing cats have shown minimal toxicity and cyclophosphamide at clinically used dosages rarely requires dosage adjustment or treatment delays. Dose intensity appears important for treatment of most cancers; the aim of this study was to perform a modified dose escalation study of cyclophosphamide to establish the maximally tolerated dosage (MTD) for intravenous cyclophosphamide in cats. The dose limiting toxicity appeared to be neutropenia, and 30% of cats experienced grade 3 or grade 4 neutropenia at a cyclophosphamide dosage of 480mg/m2, which was determined as the MTD. Delayed neutropenia was observed commonly at higher dosages. Thrombocytopenia was less common than neutropenia, and always transient. Gastrointestinal toxicities were uncommon even at MTD. The recommended dosage for single agent cyclophosphamide in cats is 460mg/m2 with a post-treatment interval of three weeks, with hematology performed before any subsequent chemotherapy is administered. This dosage appears safe in combination with prednisolone and l-asparaginase; but has not been evaluated in combination with other chemotherapy agents, or with a post-treatment interval shorter than 3 weeks. Such combinations and shorter intervals are found in some protocols, so this recommended cyclophosphamide dose cannot be considered a direct substitute for cyclophosphamide dosages in existing protocols. There is a suggestion that inadequate renal function may exacerbate the myelosuppression of cyclophosphamide which should be further evaluated.


Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Doenças do Gato/tratamento farmacológico , Ciclofosfamida/administração & dosagem , Animais , Antineoplásicos Alquilantes/efeitos adversos , Gatos , Ciclofosfamida/efeitos adversos , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Infusões Intravenosas/veterinária , Linfoma/tratamento farmacológico , Linfoma/veterinária , Masculino , Neoplasias Mamárias Animais/tratamento farmacológico , Neutropenia/induzido quimicamente , Neutropenia/veterinária , Sarcoma/tratamento farmacológico , Sarcoma/veterinária , Resultado do Tratamento
5.
Leukemia ; 32(2): 273-284, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28701730

RESUMO

Chromosomal rearrangements of the human MLL/KMT2A gene are associated with infant, pediatric, adult and therapy-induced acute leukemias. Here we present the data obtained from 2345 acute leukemia patients. Genomic breakpoints within the MLL gene and the involved translocation partner genes (TPGs) were determined and 11 novel TPGs were identified. Thus, a total of 135 different MLL rearrangements have been identified so far, of which 94 TPGs are now characterized at the molecular level. In all, 35 out of these 94 TPGs occur recurrently, but only 9 specific gene fusions account for more than 90% of all illegitimate recombinations of the MLL gene. We observed an age-dependent breakpoint shift with breakpoints localizing within MLL intron 11 associated with acute lymphoblastic leukemia and younger patients, while breakpoints in MLL intron 9 predominate in AML or older patients. The molecular characterization of MLL breakpoints suggests different etiologies in the different age groups and allows the correlation of functional domains of the MLL gene with clinical outcome. This study provides a comprehensive analysis of the MLL recombinome in acute leukemia and demonstrates that the establishment of patient-specific chromosomal fusion sites allows the design of specific PCR primers for minimal residual disease analyses for all patients.


Assuntos
Histona-Lisina N-Metiltransferase/genética , Leucemia Mieloide Aguda/genética , Proteína de Leucina Linfoide-Mieloide/genética , Adulto , Criança , Aberrações Cromossômicas , Quebra Cromossômica , Feminino , Rearranjo Gênico/genética , Humanos , Lactente , Masculino , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética/genética
6.
Phys Plasmas ; 24(5): 056312, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28611532

RESUMO

For several years, we have been calculating the radiation drive in laser-heated gold hohlraums using flux-limited heat transport with a limiter of 0.15, tabulated values of local thermodynamic equilibrium gold opacity, and an approximate model for not in a local thermodynamic equilibrium (NLTE) gold emissivity (DCA_2010). This model has been successful in predicting the radiation drive in vacuum hohlraums, but for gas-filled hohlraums used to drive capsule implosions, the model consistently predicts too much drive and capsule bang times earlier than measured. In this work, we introduce a new model that brings the calculated bang time into better agreement with the measured bang time. The new model employs (1) a numerical grid that is fully converged in space, energy, and time, (2) a modified approximate NLTE model that includes more physics and is in better agreement with more detailed offline emissivity models, and (3) a reduced flux limiter value of 0.03. We applied this model to gas-filled hohlraum experiments using high density carbon and plastic ablator capsules that had hohlraum He fill gas densities ranging from 0.06 to 1.6 mg/cc and hohlraum diameters of 5.75 or 6.72 mm. The new model predicts bang times to within ±100 ps for most experiments with low to intermediate fill densities (up to 0.85 mg/cc). This model predicts higher temperatures in the plasma than the old model and also predicts that at higher gas fill densities, a significant amount of inner beam laser energy escapes the hohlraum through the opposite laser entrance hole.

7.
Aust Vet J ; 95(7): 227-231, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28653386

RESUMO

BACKGROUND: Olfactory neuroblastoma is a rare malignancy of the nasal cavity in dogs that is thought to arise from specialised sensory neuroendocrine olfactory cells derived from the neural crest. CASE REPORT: An 8-year-old dog was presented for reclusiveness and pacing. On CT and MRI, a contract-enhancing mass was disclosed within the rostral fossa, extending caudally from the cribriform plate into the left nasal sinus. Surgical excision was performed and the diagnosis was histological grade III (Hyams grading scheme) olfactory neuroblastoma. Based on human CT criteria this was high stage (modified Kadish stage C). Surgical excision was incomplete and was followed by curative-intent radiation therapy using a linear accelerator to a total dose of 48 Gy. CONCLUSION: The dog survived 20 months after diagnosis. Although olfactory neuroblastoma is a rare tumour in dogs, aggressive local therapy may allow for prolonged survival, even when the tumour is advanced.


Assuntos
Doenças do Cão/diagnóstico , Estesioneuroblastoma Olfatório/veterinária , Cavidade Nasal/patologia , Neoplasias Nasais/veterinária , Animais , Doenças do Cão/terapia , Cães , Estesioneuroblastoma Olfatório/diagnóstico , Estesioneuroblastoma Olfatório/terapia , Masculino , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/terapia , Seios Paranasais , Olfato
8.
J Vet Intern Med ; 31(4): 1074-1080, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28514049

RESUMO

BACKGROUND: Cutaneous plasmacytosis (CP) is a syndrome of multiple cutaneous plasma cell tumors, in the absence of multiple myeloma. Although rare in both humans and dogs, treatment recommendations are usually extrapolated from multiple myeloma protocols. To date, no case series of CP have been described in the veterinary literature. HYPOTHESIS/OBJECTIVES: To describe clinical presentation, determine treatment response rates and duration, and report overall survival of dogs with CP. ANIMALS: Twenty-one client-owned dogs with CP. METHODS: Medical records of 21 dogs with CP were reviewed. Diagnosis was based on histopathologic evaluation of at least 1 representative cutaneous or subcutaneous lesion in dogs with ≥3 lesions. Dogs with suspicion of multiple myeloma were excluded. RESULTS: The most commonly affected breeds were the golden (5/21) and Labrador retriever (3/21). Fourteen of 21 dogs had >10 lesions, with some having >100. Lesions commonly were described as round, raised, pink-to-red, and variably alopecic or ulcerated. The most commonly used drug protocol was combined melphalan and prednisone, with an overall response rate (ORR) of 73.7% (14/19 dogs). Single-agent lomustine was associated with a similar ORR of 71.4% (5/7 dogs). For all treatments combined, the median progression-free interval after the first treatment was 153 days. The median survival time from the first treatment was 542 days. CONCLUSIONS AND CLINICAL IMPORTANCE: Alkylating agents were effective in inducing remission of CP; corticosteroids, melphalan, and lomustine were the most commonly used drugs. Survival times were similar to those reported in dogs with multiple myeloma treated with alkylating agents.


Assuntos
Doenças do Cão/patologia , Plasmocitoma/veterinária , Neoplasias Cutâneas/veterinária , Animais , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/uso terapêutico , Doenças do Cão/diagnóstico , Doenças do Cão/tratamento farmacológico , Doenças do Cão/mortalidade , Cães , Quimioterapia Combinada/veterinária , Feminino , Lomustina/uso terapêutico , Masculino , Melfalan/administração & dosagem , Melfalan/uso terapêutico , Plasmocitoma/diagnóstico , Plasmocitoma/tratamento farmacológico , Plasmocitoma/patologia , Prednisona/administração & dosagem , Prednisona/uso terapêutico , Pele/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia
9.
Aust Vet J ; 95(1-2): 37-40, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28124419

RESUMO

BACKGROUND: Histiocytic sarcomas (HS) frequently metastasise, most commonly to visceral sites, but also to regional lymph nodes. Nodal metastases are associated with a poorer prognosis. This retrospective study aimed to evaluate prognostic factors, including the effect of adjuvant chemotherapy, on survival in dogs with nodal, but not systemic, metastases from HS. METHODS: Retrospective case series of 12 dogs with histologically diagnosed HS metastatic to lymph nodes treated with surgery with and without adjuvant chemotherapy. RESULTS: All dogs had histological evidence of metastasis to lymph nodes, with no clinical evidence for metastasis to viscera. Eight dogs that received chemotherapy had a median estimated survival of 219 days (range 77-1638 days); 1- and 2-year estimated survival rates were 37.7%. Median survival time for 4 dogs with nodal metastases that did not receive chemotherapy was 57 days (range 39-136 days) with none alive 1 year after surgery CONCLUSION: Survival for dogs with only regional nodal metastases from HS appeared to be improved by adjuvant chemotherapy.


Assuntos
Quimioterapia Adjuvante/veterinária , Doenças do Cão/tratamento farmacológico , Sarcoma Histiocítico/veterinária , Animais , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Cães , Feminino , Sarcoma Histiocítico/tratamento farmacológico , Sarcoma Histiocítico/patologia , Sarcoma Histiocítico/cirurgia , Linfonodos/patologia , Metástase Linfática , Masculino , Prognóstico , Estudos Retrospectivos , Sobrevida , Análise de Sobrevida
10.
Vet Comp Oncol ; 15(4): 1124-1135, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27696684

RESUMO

Many chemotherapy drugs used in human patients are discarded after single use or within 24 h of reconstitution, as per the manufacturer's product label recommendations. This can be wasteful and costly to veterinary clients. This report reviews the published stability and storage data for 19 injectable chemotherapy drugs commonly used in veterinary medicine. Based on these data, storage procedures are presented, assuming aseptic technique and a closed system drug transfer device (CSDTD) are used for drug preparation and handling. Further studies on the risk of microbiological contamination of chemotherapeutics using a CSDTD, and validated high quality drug assays such as stability-indicating high-performance liquid chromatography, are required. The authors' intent is not to supersede product label recommendations, but to suggest that longer storage without significant loss of drug efficacy may be possible, thus reducing the costs of chemotherapeutics to some veterinary clients.


Assuntos
Estabilidade de Medicamentos , Armazenamento de Medicamentos , Drogas Veterinárias , Animais , Antineoplásicos/administração & dosagem , Injeções , Drogas Veterinárias/administração & dosagem
11.
Pediatr Blood Cancer ; 64(6)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27905678

RESUMO

Aurora kinases regulate mitosis and are commonly overexpressed in leukemia. This phase I/IIa study of AT9283, a multikinase inhibitor, was designed to identify maximal tolerated doses, safety, pharmacokinetics, and pharmacodynamic activity in children with relapsed/refractory acute leukemia. The trial suffered from poor recruitment and terminated early, therefore failing to identify its primary endpoints. AT9283 caused tolerable toxicity, but failed to show clinical responses. Future trials should be based on robust preclinical data that provide an indication of which patients may benefit from the experimental agent, and recruitment should be improved through international collaborations and early combination with established treatment strategies.


Assuntos
Aurora Quinases/antagonistas & inibidores , Benzimidazóis/administração & dosagem , Benzimidazóis/farmacocinética , Leucemia/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacocinética , Ureia/análogos & derivados , Doença Aguda , Adolescente , Benzimidazóis/efeitos adversos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Leucemia/enzimologia , Masculino , Dose Máxima Tolerável , Inibidores de Proteínas Quinases/efeitos adversos , Ureia/administração & dosagem , Ureia/efeitos adversos , Ureia/farmacocinética
12.
Leukemia ; 31(8): 1779-1787, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27922598

RESUMO

The human EphA3 gene was discovered in a pre-B acute lymphoblastic leukemia (pre-B-ALL) using the EphA3-specific monoclonal antibody (mAb), IIIA4, which binds and activates both human and mouse EphA3. We use two models of human pre-B-ALL to examine EphA3 function, demonstrating effects on pre-B-cell receptor signaling. In therapeutic targeting studies, we demonstrated antitumor effects of the IIIA4 mAb in EphA3-expressing leukemic xenografts and no antitumor effect in the xenografts with no EphA3 expression providing evidence that EphA3 is a functional therapeutic target in pre-B-ALL. Here we show that the therapeutic effect of the anti-EphA3 antibody was greatly enhanced by adding an α-particle-emitting 213Bismuth payload.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Receptor EphA3/imunologia , Animais , Bismuto , Linhagem Celular Tumoral , Humanos , Imunoterapia , Camundongos , Receptor EphA3/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Vet Comp Oncol ; 14(3): 252-62, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24735412

RESUMO

This retrospective study identified prognostic factors associated with survival; and compared survival data in 94 canine mammary carcinoma (MCA) dogs treated with surgery (n = 58), or surgery and adjunct chemotherapy (n = 36), and a subset of dogs with poor prognostic factors. On multivariate analysis independent predictors of median survival time (MST) were clinical stage, lymphatic invasion (LI; present 179 days; none 1098 days), ulceration (present 118 days; none 443 days) and surgical margins (incomplete 70 days; complete 872 days). Complete surgical margins were associated with MST in dogs with stages 1-3 MCA (incomplete 68 days; complete 1098 days) and dogs with LI (incomplete 70 days; complete 347 days). There was no statistically significant improvement in MST in dogs with advanced disease (stage 4 or LI) treated with adjunctive chemotherapy (chemotherapy 228 days; none 194 days); although five dogs with complete surgical margins that received mitoxantrone and carboplatin had a mean survival of 1139 days.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma/veterinária , Doenças do Cão/cirurgia , Neoplasias Mamárias Animais/cirurgia , Animais , Antineoplásicos/administração & dosagem , Carcinoma/patologia , Carcinoma/cirurgia , Quimioterapia Adjuvante/veterinária , Doenças do Cão/tratamento farmacológico , Doenças do Cão/patologia , Cães , Feminino , Neoplasias Mamárias Animais/patologia , Estudos Retrospectivos , Resultado do Tratamento
14.
Leukemia ; 27(7): 1451-60, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23563239

RESUMO

Significant improvements in survival for children with acute myeloid leukaemia (AML) have been made over the past three decades, with overall survival rates now approximately 60-70%. However, these gains can be largely attributed to more intensive use of conventional cytotoxics made possible by advances in supportive care, and although over 90% of children achieve remission with frontline therapy, approximately one third in current protocols relapse. Furthermore, late effects of therapy cause significant morbidity for many survivors. Novel therapies are therefore desperately needed. Early-phase paediatric trials of several new agents such as clofarabine, sorafenib and gemtuzumab ozogamicin have shown encouraging results in recent years. Due to the relatively low incidence of AML in childhood, the success of paediatric early-phase clinical trials is largely dependent upon collaborative clinical trial design by international cooperative study groups. Successfully incorporating novel therapies into frontline therapy remains a challenge, but the potential for significant improvement in the duration and quality of survival for children with AML is high.


Assuntos
Nucleotídeos de Adenina/uso terapêutico , Aminoglicosídeos/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Arabinonucleosídeos/uso terapêutico , Leucemia Monocítica Aguda/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Antineoplásicos/uso terapêutico , Criança , Clofarabina , Gemtuzumab , Humanos , Imunotoxinas/uso terapêutico , Niacinamida/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Sorafenibe
15.
J Vet Intern Med ; 26(5): 1164-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22882592

RESUMO

BACKGROUND: Splenic fibrohistiocytic nodules (SFHN) are commonly diagnosed. It is suspected that these represent a heterogeneous group of malignant and nonmalignant diseases, separation of which could improve the ability of clinicians to prognosticate for dogs. HYPOTHESIS/OBJECTIVES: Immunohistochemistry will differentiate histologic diagnoses within the group of SFHN; survival after splenectomy is associated with those histologic types. ANIMALS: Thirty-two dogs with SFHN treated by or under direction from veterinary oncologists. METHODS: Retrospective case record analysis from dogs followed from splenectomy until death. Clinical, histopathologic, and immunohistochemistry data analyzed for an association with survival time. RESULTS: Thirty-two dogs had SFHN; grade 1 (2 dogs), grade 2 (9 dogs), and grade 3 (lymphoid percentage <40%; 21 dogs). Twenty-two dogs died, 10 were censored (9 alive median of 883 days after splenectomy). Median overall survival was 387 days, and grade 3 SFHN was negatively [corrected] associated with survival time as previously reported (P < .001). Of 31 available samples, dogs had diseases reclassified as nodular hyperplasia (13; 8 complex, 5 lymphoid including 2 marginal zone), lymphoma (4; 2 marginal zone lymphoma, 1 high grade B-cell lymphoma, and 1 marginal zone transitional to high grade B-cell lymphoma), 8 stromal sarcomas, and 6 histiocytic sarcomas. Dogs with histiocytic sarcoma had worse survival (median 74 days) than dogs with other diseases. CONCLUSIONS AND CLINICAL IMPORTANCE: Splenic histiocytic sarcoma is an aggressive disease; however, some dogs with stromal sarcomas had long survival times. The term SFHN is no longer warranted for this group of disorders.


Assuntos
Doenças do Cão/patologia , Sarcoma Histiocítico/veterinária , Neoplasias Esplênicas/veterinária , Animais , Doenças do Cão/metabolismo , Doenças do Cão/cirurgia , Cães , Feminino , Sarcoma Histiocítico/metabolismo , Sarcoma Histiocítico/patologia , Sarcoma Histiocítico/cirurgia , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Esplenectomia/veterinária , Neoplasias Esplênicas/metabolismo , Neoplasias Esplênicas/patologia , Neoplasias Esplênicas/cirurgia
16.
Leukemia ; 26(7): 1462-70, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22354205

RESUMO

Acquired resistance to selective FLT3 inhibitors is an emerging clinical problem in the treatment of FLT3-ITD(+) acute myeloid leukaemia (AML). The paucity of valid pre-clinical models has restricted investigations to determine the mechanism of acquired therapeutic resistance, thereby limiting the development of effective treatments. We generated selective FLT3 inhibitor-resistant cells by treating the FLT3-ITD(+) human AML cell line MOLM-13 in vitro with the FLT3-selective inhibitor MLN518, and validated the resistant phenotype in vivo and in vitro. The resistant cells, MOLM-13-RES, harboured a new D835Y tyrosine kinase domain (TKD) mutation on the FLT3-ITD(+) allele. Acquired TKD mutations, including D835Y, have recently been identified in FLT3-ITD(+) patients relapsing after treatment with the novel FLT3 inhibitor, AC220. Consistent with this clinical pattern of resistance, MOLM-13-RES cells displayed high relative resistance to AC220 and Sorafenib. Furthermore, treatment of MOLM-13-RES cells with AC220 lead to loss of the FLT3 wild-type allele and the duplication of the FLT3-ITD-D835Y allele. Our FLT3-Aurora kinase inhibitor, CCT137690, successfully inhibited growth of FLT3-ITD-D835Y cells in vitro and in vivo, suggesting that dual FLT3-Aurora inhibition may overcome selective FLT3 inhibitor resistance, in part due to inhibition of Aurora kinase, and may benefit patients with FLT3-mutated AML.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Mutação/genética , Inibidores de Proteínas Quinases/farmacologia , Sequências de Repetição em Tandem/genética , Tirosina Quinase 3 Semelhante a fms/genética , Animais , Apoptose/efeitos dos fármacos , Aurora Quinases , Benzenossulfonatos/farmacologia , Benzotiazóis/farmacologia , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Imidazóis/farmacologia , Camundongos , Camundongos Nus , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Piperazinas/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridinas/farmacologia , Quinazolinas/farmacologia , Sorafenibe , Células Tumorais Cultivadas , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/metabolismo
17.
Vet Pathol ; 48(1): 7-18, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20664014

RESUMO

There is an increasing need for more accurate prognostic and predictive markers in veterinary oncology because of an increasing number of treatment options, the increased financial costs associated with treatment, and the emotional stress experienced by owners in association with the disease and its treatment. Numerous studies have evaluated potential prognostic and predictive markers for veterinary neoplastic diseases, but there are no established guidelines or standards for the conduct and reporting of prognostic studies in veterinary medicine. This lack of standardization has made the evaluation and comparison of studies difficult. Most important, translating these results to clinical applications is problematic. To address this issue, the American College of Veterinary Pathologists' Oncology Committee organized an initiative to establish guidelines for the conduct and reporting of prognostic studies in veterinary oncology. The goal of this initiative is to increase the quality and standardization of veterinary prognostic studies to facilitate independent evaluation, validation, comparison, and implementation of study results. This article represents a consensus statement on the conduct and reporting of prognostic studies in veterinary oncology from veterinary pathologists and oncologists from around the world. These guidelines should be considered a recommendation based on the current state of knowledge in the field, and they will need to be continually reevaluated and revised as the field of veterinary oncology continues to progress. As mentioned, these guidelines were developed through an initiative of the American College of Veterinary Pathologists' Oncology Committee, and they have been reviewed and endorsed by the World Small Animal Veterinary Association.


Assuntos
Oncologia/normas , Neoplasias/veterinária , Guias de Prática Clínica como Assunto , Medicina Veterinária/normas , Animais , Progressão da Doença , Neoplasias/patologia , Prognóstico
18.
J Vet Intern Med ; 24(6): 1528-31, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21155191

RESUMO

BACKGROUND: Histiocytic sarcoma (HS) is an aggressive neoplasm in dogs, and in most instances, the disease is localized, but not amenable to surgical removal, or is disseminated. Affected patients usually die within 6 months. There have been no prospective studies to determine efficacy of single-agent chemotherapy in dogs with HS. HYPOTHESIS: Single-agent CCNU [1-(2-chloroethyl)3-cyclohexyl-1-nitrosourea; lomustine] has antitumor activity against HS in dogs. ANIMALS: Twenty-one dogs with histologically confirmed, nonresectable localized or disseminated HS. METHODS: Prospective, open-label phase II clinical trial in which dogs with previously untreated HS were uniformly treated with CCNU as a single oral dosage of 90 mg/m2 every 4 weeks. The primary outcome measure was reduction in tumor size. RESULTS: Fourteen dogs with disseminated HS and 7 with localized HS were enrolled between 1999 and 2008. Overall response rate was 29% (95% confidence interval [CI], 14­50%) for a median of 96 days (95% CI, 55­137 days). Three dogs (1 disseminated, 2 localized) had complete responses lasting for 54­269 days and 3 dogs (2 disseminated, 1 localized) had partial responses lasting for 78­112 days. CONCLUSIONS AND CLINICAL IMPORTANCE: CCNU, when used as a single agent, has activity against HS in dogs. Evaluation of CCNU postoperatively for dogs with resectable localized HS and as part of combination therapy for tumors that are nonresectable or disseminated should be considered.


Assuntos
Antineoplásicos/uso terapêutico , Doenças do Cão/tratamento farmacológico , Sarcoma Histiocítico/veterinária , Lomustina/uso terapêutico , Animais , Antineoplásicos/administração & dosagem , Cães , Feminino , Sarcoma Histiocítico/tratamento farmacológico , Lomustina/administração & dosagem , Masculino
19.
Leukemia ; 24(4): 671-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20147976

RESUMO

Aurora kinases are a family of protein kinases that have a key role in multiple stages of mitosis. Over-expression of Aurora kinases, particularly Aurora A, has been demonstrated in a number of solid tumors and hematological malignancies. Not surprisingly, these serine/threonine kinases have become attractive small molecule targets for cancer therapeutics, with several inhibitors currently in early-phase clinical trials. A small number of compounds developed to date are highly selective for either Aurora A or Aurora B, while the majority inhibit both Aurora A and Aurora B; many of these compounds exhibit 'off-target' inhibition of kinases such as ABL, JAK2 and FLT3. It is currently unclear whether the therapeutic activity of these compounds in leukemia is primarily due to selective Aurora or multi-kinase inhibition. The most promising application for Aurora kinase inhibitors to date appears to be in FLT3-mutated acute myeloid leukemia (AML) and imatinib-resistant chronic myeloid leukemia/Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia, particularly when caused by the T315I mutation. Here we review the growing body of evidence supporting the use of Aurora kinase inhibitors as effective agents for AML and Ph+ leukemias.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mieloide Aguda/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Aurora Quinase B , Aurora Quinases , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mieloide Aguda/enzimologia
20.
J Vet Intern Med ; 23(2): 317-22, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19192147

RESUMO

BACKGROUND: Chemotherapy for multicentric canine lymphoma has favorable results. The gastrointestinal (GI) tract is the most common extranodal site of canine lymphoma, but there have been no prospective studies to determine outcome when dogs with GI lymphoma are treated with chemotherapy. HYPOTHESIS: Treatment with a multiagent chemotherapy protocol is associated with a poor outcome in dogs with GI lymphoma. ANIMALS: Eighteen dogs with histologically confirmed GI lymphoma. METHODS: Prospective clinical trial in which dogs with GI lymphoma were treated with a 20-week combination chemotherapy protocol consisting of induction and consolidation phases. RESULTS: Thirteen dogs had primary GI lymphoma and 5 had multicentric lymphoma with GI involvement. The majority of the lymphomas (63%) were of T-cell origin. Overall remission rate was 56%; 9 dogs achieved a complete remission for a median of 86 days (range, 22-420 days) and 1 dog achieved a partial remission for 26 days. Overall median survival time was 77 days (range, 6-700 days). Dogs that failed to achieve a remission (10 versus 117 days; P= .002) or had diarrhea at initial presentation (70 versus 700 days; P < .001) had shorter survival times. CONCLUSION AND CLINICAL IMPORTANCE: The response and survival of dogs with GI lymphoma treated with multiagent chemotherapy is poor but long-term survival is possible.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doenças do Cão/tratamento farmacológico , Neoplasias Gastrointestinais/veterinária , Linfoma/veterinária , Animais , Asparagina/administração & dosagem , Contagem de Células Sanguíneas/veterinária , Ciclofosfamida/administração & dosagem , Doenças do Cão/sangue , Doenças do Cão/patologia , Cães , Doxorrubicina/administração & dosagem , Feminino , Neoplasias Gastrointestinais/sangue , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/patologia , Lomustina/administração & dosagem , Linfoma/sangue , Linfoma/tratamento farmacológico , Linfoma/patologia , Masculino , Mecloretamina/administração & dosagem , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Estudos Prospectivos , Indução de Remissão , Taxa de Sobrevida , Vincristina/administração & dosagem
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