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1.
Molecules ; 29(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38792119

RESUMO

To investigate the bioactivities of fresh garlic and its processed product, black garlic, we conducted comparative analyses of antioxidant, anti-inflammatory, innate immune activation, and anti-cancer activities in addition to the chemical composition (sugar, amino acid, and polyphenol contents) of these materials. Simultaneous assay using neutrophil-like cells showed that fresh garlic exhibited antioxidant and innate immunostimulatory activities, whereas black garlic displayed a potent anti-inflammatory effect. The antioxidant activity index was correlated with phenol and flavonoid contents, while the innate immunostimulatory activity was correlated with fructan content. Furthermore, some black garlics with low fructose content were found to inhibit the proliferation of UM-UC-3 cancer cells, while other black garlics rich in fructose increased UM-UC-3 cell proliferation. It was shown that the processing of fresh garlic could change the composition of sugars, antioxidants, and amino acids, which have different effects on neutrophil-like cells and UM-UC-3 cells, as well as on bioactivities.


Assuntos
Antioxidantes , Proliferação de Células , Alho , Alho/química , Antioxidantes/farmacologia , Antioxidantes/química , Humanos , Proliferação de Células/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Linhagem Celular Tumoral , Aminoácidos/análise , Aminoácidos/química , Polifenóis/análise , Polifenóis/química , Polifenóis/farmacologia , Fenóis/análise , Fenóis/química , Fenóis/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Flavonoides/análise , Flavonoides/química , Flavonoides/farmacologia
2.
J Vet Sci ; 25(1): e15, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38311328

RESUMO

BACKGROUND: The anti-programmed death 1 (PD-1) antibody has led to durable clinical responses in a wide variety of human tumors. We have previously developed the caninized anti-canine PD-1 antibody (ca-4F12-E6) and evaluated its therapeutic properties in dogs with advance-staged oral malignant melanoma (OMM), however, their therapeutic effects on other types of canine tumors remain unclear. OBJECTIVE: The present clinical study was carried out to evaluate the safety profile and clinical efficacy of ca-4F12-E6 in dogs with advanced solid tumors except for OMM. METHODS: Thirty-eight dogs with non-OMM solid tumors were enrolled prospectively and treated with ca-4F12-E6 at 3 mg/kg every 2 weeks of each 10-week treatment cycle. Adverse events (AEs) and treatment efficacy were graded based on the criteria established by the Veterinary Cooperative Oncology Group. RESULTS: One dog was withdrawn, and thirty-seven dogs were evaluated for the safety and efficacy of ca-4F12-E6. Treatment-related AEs of any grade occurred in 13 out of 37 cases (35.1%). Two dogs with sterile nodular panniculitis and one with myasthenia gravis and hypothyroidism were suspected of immune-related AEs. In 30 out of 37 dogs that had target tumor lesions, the overall response and clinical benefit rates were 6.9% and 27.6%, respectively. The median progression-free survival and overall survival time were 70 days and 215 days, respectively. CONCLUSIONS: The present study demonstrated that ca-4F12-E6 was well-tolerated in non-OMM dogs, with a small number of cases showing objective responses. This provides evidence supporting large-scale clinical trials of anti-PD-1 antibody therapy in dogs.


Assuntos
Doenças do Cão , Melanoma , Neoplasias Cutâneas , Cães , Animais , Humanos , Melanoma/tratamento farmacológico , Melanoma/veterinária , Melanoma/patologia , Receptor de Morte Celular Programada 1 , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/veterinária , Neoplasias Cutâneas/patologia , Resultado do Tratamento , Doenças do Cão/tratamento farmacológico
3.
Res Vet Sci ; 169: 105174, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340381

RESUMO

Statins are inhibitors of the mevalonic acid pathway that mediates cellular metabolism by producing cholesterol and isoprenoids and are widely used in treating hypercholesterolaemia in humans. Lipophilic statins, including simvastatin, induce death in various tumour cells. However, the cytotoxic mechanisms of statins in tumour cells remain largely unexplored. This study aimed to elucidate the cytotoxic mechanisms of simvastatin in canine lymphoma cells. Simvastatin induced cell death via c-Jun N-terminal kinase (JNK) activation and autophagy in canine T-cell lymphoma cell lines Ema and UL-1, but not in B-cell lines. Cell death was mediated by induction of caspase-dependent apoptosis in UL-1 cells, but not in Ema cells. Blockade of autophagy by lysosomal inhibitors attenuated simvastatin-induced JNK activation and cell death. Isoprenoids, including farnesyl pyrophosphate and geranylgeranyl pyrophosphate, attenuated simvastatin-induced autophagy, JNK activation, and cell death. In UL-1 cells, simvastatin treatment resulted in the cell cycle arrest at the G2/M phase, which was altered to G0/1 phase cell cycle arrest by treatment with lysosomal inhibitors. These findings demonstrate that depletion of isoprenoids by simvastatin induces autophagy-mediated cell death via downstream JNK activation and cell cycle dysregulation in canine T-cell lymphoma cells.


Assuntos
Antineoplásicos , Doenças do Cão , Inibidores de Hidroximetilglutaril-CoA Redutases , Linfoma de Células T , Animais , Cães , Humanos , Sinvastatina/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Linhagem Celular Tumoral , Ciclo Celular , Divisão Celular , Apoptose , Morte Celular , Antineoplásicos/farmacologia , Autofagia , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/veterinária , Terpenos/farmacologia , Doenças do Cão/tratamento farmacológico
4.
Vet Comp Oncol ; 22(2): 303-309, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38287199

RESUMO

Canine lymphoma is a disease with high morbidity and poor long-term prognosis, despite a high response rate to chemotherapy. In this study, we focused on liquid biopsy, in which small amounts of substances from body fluids were analysed, to determine whether cell-free DNA (cfDNA) in the plasma can be used as a biomarker for lymphoma in dogs. We found that 23 patients with lymphoma had significantly higher cfDNA concentrations than the 12 healthy dogs (median 2360 ng/mL versus 299 ng/mL, p < .0001). Polymerase chain reaction for antigen receptor rearrangement (PARR) was also employed using cfDNA from the lymphoma group to investigate whether cfDNA could be used for the detection of genetic clonality of lymphomas, as well as the genomic DNA (gDNA) extracted from an original lesion in each case. The correlation of the PARR results between cfDNA and gDNA was observed in 100% of B-cell lymphomas (10/10), 77.8% of T-cell lymphomas (7/9), and 100% of other types of lymphomas (4/4), respectively. These results indicate that plasma cfDNA levels are increasing in canine lymphoma patients, that cfDNA concentration can be a novel diagnostic tool, and that it can be used as a diagnostic tool for PARR.


Assuntos
Ácidos Nucleicos Livres , Doenças do Cão , Linfoma , Cães , Animais , Doenças do Cão/sangue , Doenças do Cão/genética , Doenças do Cão/diagnóstico , Linfoma/veterinária , Linfoma/sangue , Linfoma/genética , Linfoma/diagnóstico , Ácidos Nucleicos Livres/sangue , Feminino , Masculino , Biomarcadores Tumorais/sangue , Genótipo , Reação em Cadeia da Polimerase/veterinária , DNA de Neoplasias/sangue , DNA de Neoplasias/genética
5.
J Vet Med Sci ; 85(12): 1269-1276, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37899236

RESUMO

Gallbladder mucocele (GBM) is one of the most common gallbladder diseases in dogs. Its pathogenesis has not yet been clarified, but excessive accumulation of a secretory gel-forming mucin, MUC5AC in the gallbladder has been reported. This study aimed to ascertain if MUC5AC overproduction resulted in mucus accumulation in the gallbladder during GBM development. Eleven dogs undergoing cholecystectomy who were pathologically diagnosed with GBM were included, and the expression level of mucins, particularly MUC5AC and MUC5B, in their gallbladder epithelial cells was compared with those in normal gallbladder epithelial cells. On reverse transcription-quantitative polymerase chain reaction screening, there was a significant difference (P<0.05) in the mRNA expression level of MUC1, but not of other mucins including MUC5AC and MUC5B, between mucocele and normal gallbladder epithelial cells. Protein expression levels were also evaluated for MUC5AC and MUC5B using immunohistochemistry. There was little immunoreactivity for MUC5AC, whereas MUC5B showed definitive staining in gallbladder epithelial cells. There was no difference in MUC5AC and MUC5B protein expression levels between mucocele and normal gallbladder epithelial cells. These data suggest that excessive production of mucin, especially MUC5AC and MUC5B, does not occur in canine GBM, and that abnormal mucus excretion, rather than excessive mucus production, may be the cause of GBM development.


Assuntos
Doenças do Cão , Doenças da Vesícula Biliar , Mucocele , Cães , Animais , Mucocele/veterinária , Mucocele/metabolismo , Células Epiteliais/metabolismo , Doenças da Vesícula Biliar/veterinária , Doenças do Cão/metabolismo
6.
J Vet Med Sci ; 85(10): 1047-1051, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37587049

RESUMO

A 1-year-old spayed female Miniature Schnauzer had chronic hyponatremia, accompanied by polyuria and polydipsia. Blood tests and urinalysis revealed severe hyponatremia, low plasma osmolality with euvolemia, and increased sodium excretion in urine. Hypothyroidism and hypoadrenocorticism were ruled out as causes. These findings led to the diagnosis of syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Magnetic resonance imaging (MRI) showed dilation of the lateral ventricles, indicating severe hydrocephalus. Tolvaptan, a vasopressin V2 receptor antagonist commonly used in human SIADH, was administered along with water restriction. This treatment resulted in a consistent increase in plasma sodium levels without any adverse effects. This case report represents the first documented evidence of the therapeutic efficacy of tolvaptan in treating SIADH in a dog.


Assuntos
Doenças do Cão , Hiponatremia , Síndrome de Secreção Inadequada de HAD , Cães , Feminino , Humanos , Animais , Tolvaptan/uso terapêutico , Hiponatremia/tratamento farmacológico , Hiponatremia/etiologia , Hiponatremia/veterinária , Síndrome de Secreção Inadequada de HAD/complicações , Síndrome de Secreção Inadequada de HAD/tratamento farmacológico , Síndrome de Secreção Inadequada de HAD/veterinária , Antagonistas dos Receptores de Hormônios Antidiuréticos/uso terapêutico , Vasopressinas/uso terapêutico , Sódio , Benzazepinas/uso terapêutico , Doenças do Cão/tratamento farmacológico
7.
J Vet Med Sci ; 85(1): 99-104, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36450591

RESUMO

Canine lymphoma/leukemia cell lines with p16 protein expressions: high (17-71 and GL-1) and low (CLBL-1, CLC, Nody-1, and UL-1) were treated in vitro with cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors, palbociclib or abemaciclib. Cell proliferation decreased as a result, with higher IC50 levels observed in the high p16 (17-71 and GL-1) and one low p16 (UL-1) cell lines compared with the low p16 cells (CLBL-1, CLC, and Nody-1). As expected, palbociclib and abemaciclib treatment reduced pRb phosphorylation in a dose-dependent manner, especially in cells with low p16. These results suggest that CDK4/6 inhibitors have potential as new chemotherapeutic agents for canine lymphoma and high p16 protein expression may be used as a biomarker for resistance to CDK4/6 inhibitor therapy.


Assuntos
Doenças do Cão , Linfoma , Animais , Cães , Quinase 4 Dependente de Ciclina/metabolismo , Proteína do Retinoblastoma/metabolismo , Fosforilação , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Linfoma/veterinária , Doenças do Cão/tratamento farmacológico
8.
Vet Sci ; 9(8)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-36006308

RESUMO

Cyclin-dependent kinase inhibitor p16 (CDKN2A) primarily functions as a negative regulator of the retinoblastoma protein (pRb) pathway to prevent pRb phosphorylation, thus playing a critical role in cell cycle arrest. In canine lymphoma cells, methylation due to inactivation of the p16 gene has been reported. However, its protein expression has not been examined in previous studies. In our in vitro study, the gene and protein expression of p16 and phosphorylated pRb were examined simultaneously in eight canine lymphoma and leukemia cell lines (17-71, CLBL-1, GL-1, CLC, CLGL-90, Ema, Nody-1, and UL-1). Methylation of the p16 gene was also explored using the demethylation drug 5-Aza-2'-deoxycytidine (5-Aza). After 5-Aza treatment, p16 gene and protein expression increased and pRb phosphorylation decreased, suggesting that both hypermethylation of the p16 gene and pRb hyperphosphorylation occurred in four out of eight cell lines (CLBL-1, CLC, Nody-1, and UL-1). Moreover, the estimation of p16's protein expression was better than that of p16's mRNA expression because the expression of the protein was more stable than those of the gene, and highly related to the phosphorylation of pRb. These results revealed that p16's protein expression could be a promising biomarker for canine lymphoma cells.

9.
Vet Anim Sci ; 17: 100264, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35898238

RESUMO

Background: Nonregenerative anemia is occasionally seen in dogs and can be caused by many factors, among which nonregenerative immune-mediated anemia (NRIMA) and pure red cell anemia are relatively common causes. These are thought to be caused by immune-mediated destruction of the erythroid lineage and are treated with immunosuppressive drugs, but some of them are refractory or recurrent, so new treatments are needed. Objectives: To examine the efficacy of allogeneic adipose-derived stem cells (ADSCs) for the treatment of nonregerative anemia in dogs. Methods: ADSCs were administered to total five nonregenerative anemia cases; two NRIMA cases and two suspected NRIMA cases that were refractory to immunosuppressive agents, and one NRIMA case that has not been treated with immunosuppressive agents. Results: In all cases, anemia was improved, and blood transfusion was no longer necessary. Conclusions: This study suggests that allogeneic ADSCs may be one of the rescue therapies for the refractory immune-mediated anemia in dogs.

10.
Vet Comp Oncol ; 19(1): 99-108, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32779819

RESUMO

Statins are inhibitors of the mevalonate cascade that is responsible for cholesterol biosynthesis and the formation of intermediate metabolites, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP) used in the prenylation of proteins. Although statins are widely used in the treatment of hypercholesterolemia, recent studies suggest that they also inhibit proliferation of tumour cells by reducing prenylation of small GTP-binding proteins, such as, Ras. This study aimed to evaluate the effect of simvastatin on cell proliferation and Ras activation in various canine tumour cell lines, including hemangiosarcoma (HSA), melanoma, and lymphoma cell lines. Simvastatin inhibited cell proliferation of all cell lines tested in a concentration- and time-dependent manner, but the susceptibilities were different amongst the cell lines. Simvastatin induced apoptotic cell death via activation of caspase-3 and cell cycle arrest. The cytotoxic effects of simvastatin were attenuated by GGPP and FPP. Simvastatin decreased the amount of prenylated Ras and GTP-bound Ras in HSA and melanoma cell lines, but not in lymphoma cell lines. These results indicate that simvastatin induces cytotoxic effects through the depletion of GGPP and FPP in a variety of canine tumour cells, whereas multiple mechanisms are involved in the effects. Further study is required to elucidate the underlying mechanisms of simvastatin-induced cytotoxic effects in a variety of canine tumour cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , Doenças do Cão/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sinvastatina/farmacologia , Proteínas ras/metabolismo , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Inibidores de Caspase/farmacologia , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cães , Hemangiossarcoma/metabolismo , Hemangiossarcoma/veterinária , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Linfoma/metabolismo , Linfoma/veterinária , Melanoma/metabolismo , Melanoma/veterinária , Proteínas ras/genética
11.
J Vet Med Sci ; 82(1): 56-60, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31787663

RESUMO

Microparticle (MP)-associated tissue factor (TF) activity in plasma might play a role in human disseminated intravascular coagulation (DIC). The aim of this study was to compare MP-TF activity between non-DIC and DIC groups. Ten clinically healthy beagles and 26 diseased dogs were enrolled. The proportion of dogs with increased MP-TF activity was significantly higher in the DIC group than the non-DIC group (P=0.014). MP-TF activity in the DIC group was significantly higher than the non-DIC group (P=0.021). MP-TF activity positively correlated with plasma D-dimer concentration (r=0.42, P=0.034). Moreover, MP-TF activity was decreased by the time of recovery in some dogs with DIC. Larger prospective studies are warranted to assess its value as a diagnostic and prognostic biomarker in DIC.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Coagulação Intravascular Disseminada/veterinária , Doenças do Cão/sangue , Tromboplastina/metabolismo , Animais , Coagulação Intravascular Disseminada/sangue , Coagulação Intravascular Disseminada/metabolismo , Doenças do Cão/metabolismo , Cães , Feminino , Masculino , Estudos Retrospectivos
12.
J Vet Med Sci ; 81(12): 1713-1721, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31611484

RESUMO

Hypercoagulability is a common paraneoplastic complication in dogs with various malignant tumors. Importantly, tissue factor procoagulant activity (TF-PCA) induced by TF-bearing microparticles (TF-MPs) is associated with hypercoagulability in human patients with cancer. However, TF-PCA in tumor cells and the association between circulating TF-MPs and hypercoagulability in dogs with malignant tumors remain poorly understood. Therefore, the present study was conducted to evaluate the TF-PCA in various types of canine tumor cell lines and plasma in dogs with malignant tumors. Mammary gland tumor, hemangiosarcoma, and malignant melanoma cell lines, but not lymphoma cell lines, expressed TF on their surfaces and showed cellular surface and MP-associated TF-PCA. The plasma TF-PCA was elevated in some dogs that naturally developed such tumors. No significant difference was observed in plasma TF-PCA between the disseminated intravascular coagulation (DIC) group (median: 43.40; range: 3.47-85.19; n=5) and non-DIC group (median: 7.73; range: 1.70-16.13; n=12). However, plasma TF-PCA was remarkably elevated in three of five dogs with DIC. To the best of our knowledge, this is the first study to evaluate plasma TF-PCA in dogs with malignant tumors. Further studies must be conducted to determine the cellular origin of TF-MPs and the efficacy of plasma TF-PCA as a biomarker of DIC in dogs with malignant tumors.


Assuntos
Micropartículas Derivadas de Células/química , Doenças do Cão/sangue , Neoplasias/veterinária , Tromboplastina/metabolismo , Animais , Linhagem Celular Tumoral , Micropartículas Derivadas de Células/metabolismo , Doenças do Cão/patologia , Cães , Feminino , Citometria de Fluxo/veterinária , Hemangiossarcoma/patologia , Hemangiossarcoma/veterinária , Linfoma/patologia , Linfoma/veterinária , Neoplasias Mamárias Animais/patologia , Melanoma/patologia , Melanoma/veterinária , Neoplasias/sangue , Neoplasias/metabolismo
13.
Lung Cancer ; 112: 96-101, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29191607

RESUMO

OBJECTIVES: Non-small cell lung cancer (NSCLC) and chronic obstructive pulmonary disease (COPD) have been proposed to have a mutual developmental mechanism, but their association has not been fully understood. We aimed to examine the association of the mutational landscape of NSCLC with co-morbid COPD. MATERIALS AND METHODS: A total of 197 surgical specimens of early stage NSCLC were retrospectively collected from two independent sources, namely, the Japan Molecular Epidemiology for Lung Cancer Study and the Osaka City University Hospital cohort from 2010 to 2013. COPD and its severity were defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines and grading system. For molecular profiling of NSCLC patients with COPD, the extracted DNAs were deep-sequenced using next generation sequence technologies for somatic mutations in a maximum 72 cancer-associated genes. Logistic regression analysis was performed to evaluate the impact of COPD on the somatic mutations. RESULTS: The COPD group (n=77), including 56 GOLD 1 and 21 GOLD 2 or 3 patients, had 58 squamous cell lung carcinoma (SCC) cases and 19 adenocarcinoma cases. The non-COPD group (n=120) had 53 SCC cases, 64 adenocarcinoma cases, and three cases with other histology. The frequency of PIK3CA mutation was significantly higher in the COPD group than in the non-COPD group (10.4% vs. 1.7%, p=0.015). Meanwhile, NFE2L2 mutation was observed only in SCC cases, with no difference in the frequency between the two groups (17.2% vs. 17.0%). In the multivariate logistic regression model with consideration for COPD status, age, smoking dose, pathological stage, and histology, significantly more PIK3CA mutation was observed in the presence of COPD (odds ratio=5.31, 95% CI: 1.03-27.29, p=0.046). CONCLUSIONS: PIK3CA mutation is a distinctive genetic feature of NSCLC with COPD, regardless of age, smoking dose, pathological stage, and histology.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/complicações , Carcinoma Pulmonar de Células não Pequenas/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/genética , Mutação , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Estadiamento de Neoplasias , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Testes de Função Respiratória , Índice de Gravidade de Doença
14.
Can J Vet Res ; 80(1): 21-31, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26733729

RESUMO

The oncolytic effects of reovirus in various cancers have been proven in many clinical trials in human medicine. Oncolytic virotherapy using reovirus for canine cancers is being developed in our laboratory. The objective of this study was to examine the synergistic anti-cancer effects of a combination of reovirus and low doses of various chemotherapeutic agents on mammary gland tumors (MGTs) in dogs. The first part of this study demonstrated the efficacy of reovirus in canine MGTs in vitro and in vivo. Reovirus alone exerted significant cell death by means of caspase-dependent apoptosis in canine MGT cell lines. A single injection of reovirus impeded growth of canine MGT tumors in xenografted mice, but was insufficient to induce complete tumor regression. The second part of this study highlighted the anti-tumor effects of reovirus in combination with low doses of paclitaxel, carboplatin, gemcitabine, or toceranib. Enhanced synergistic activity was observed in the MGT cell line treated concomitantly with reovirus and in all the chemotherapeutic agents except toceranib. In addition, combining reovirus with paclitaxel or gemcitabine at half dosage of half maximal inhibitory concentration (IC50) enhanced cytotoxicity by activating caspase 3. Our data suggest that the combination of reovirus and low dose chemotherapeutic agents provides an attractive option in canine cancer therapy.


Les effets oncolytiques des reovirus dans divers cancers ont été prouvés lors de plusieurs essais cliniques en médecine humaine. La virothérapie oncolytique pour les cancers canins utilisant des reovirus est présentement en développement dans notre laboratoire. L'objectif de cette étude était d'examiner les effets synergiques anticancéreux d'une combinaison de reovirus et de faibles doses d'agents chimio-thérapeutiques variés sur les tumeurs des glandes mammaires (TGM) chez les chiens. La première partie de l'étude a démontré l'efficacité du reovirus sur des TGM in vitro et in vivo. Les reovirus utilisés seuls ont produit une quantité significative de mort cellulaire dans des lignées cellulaires canines de TGM via l'apoptose dépendante de la caspase. Une injection unique de reovirus interféra avec la croissance de TGM canines chez des souris ayant reçu une xénogreffe, mais était insuffisante pour induire une régression complète de la tumeur. La deuxième partie de cette étude a mis en évidence les effets anti-tumoraux des reovirus en combinaison avec de faibles doses de paclitaxel, de carboplatin, de gemcibatine, ou de toceranib. Une activité synergique augmentée fut observée dans la lignée cellulaire TGM traitée de manière concomitante avec du reovirus et tous les agents chimio-thérapeutique sauf le toceranib. De plus, en combinant le reovirus avec du paclitaxel ou de la gemcibatine à la moitié de la dose de la moitié de la concentration inhibitrice maximale (IC50) on augmenta la cytotoxicité en activant la caspase 3. Nos données suggèrent que la combinaison de reovirus et de faibles doses d'agents chimio-thérapeutiques fournie une option intéressante pour le traitement de cancer canin.(Traduit par Docteur Serge Messier).


Assuntos
Antineoplásicos/farmacologia , Doenças do Cão/terapia , Neoplasias Mamárias Animais/terapia , Vírus Oncolíticos , Reoviridae , Animais , Morte Celular , Linhagem Celular Tumoral , Proliferação de Células , Cães , Feminino , Humanos , Camundongos , Camundongos SCID , Neoplasias Experimentais
15.
J Vet Med Sci ; 78(4): 691-5, 2016 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-26638898

RESUMO

A 10-year-old female spayed mixed breed cat with a subcutaneous mass on the right hind limb was revealed with bimodal monoclonal gammopathy composed of IgA by immunoelectrophoresis and immunofixation. Approximately 1 month after referral, the cat died due to renal failure. Postmortem immunohistopathologic evaluation of the subcutaneous mass revealed neoplastic cell proliferation of plasma cells and giant myeloma cells. Neoplastic cells were also present in the liver and spleen. These results led to the diagnosis of a rare case of feline myeloma-related disorders with extramedullary plasmacytoma infiltrating in multiple locations. This report emphasizes the necessity to accumulate cases with similar clinicopathologic findings in the future.


Assuntos
Doenças do Gato/imunologia , Mieloma Múltiplo/veterinária , Paraproteinemias/veterinária , Animais , Gatos , Feminino , Imunoglobulina A , Mieloma Múltiplo/complicações , Mieloma Múltiplo/imunologia , Paraproteinemias/etiologia , Paraproteinemias/imunologia
16.
Can J Vet Res ; 79(3): 201-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26130852

RESUMO

The DNA repair protein O (6)-methylguanine-DNA methyltransferase (MGMT) causes resistance to nitrosoureas in various human cancers. In this study, we analyzed the correlation between canine lymphomas and MGMT in vitro. Two of five canine lymphoma cell lines required higher concentrations of lomustine to inhibit cell growth by 50%, but their sensitivity to the drug increased when they were cultured with an MGMT inhibitor. Fluorometric oligonucleotide assay and real-time polymerase chain reaction of these cell lines revealed MGMT activity and high MGMT mRNA expression, respectively. We analyzed the methylation status of the CpG islands of the canine MGMT gene by the bisulfite-sequencing method. Unlike human cells, the canine lymphoma cell lines did not show significant correlation between methylation status and MGMT suppression levels. Our results suggest that in canine lymphoma MGMT activity may influence sensitivity to nitrosoureas; thus, inhibition of MGMT activity would benefit nitrosourea-resistant patients. Additional studies are necessary to elucidate the mechanism of regulation of MGMT expression.


La protéine de réparation O6-méthylguanine-DNA méthyltransferase (MGMT) cause de la résistance aux produits nitroso-urée dans divers cancers humains. Dans la présente étude nous avons analysé in vitro la corrélation entre les lymphomes canins et le MGMT. Deux des cinq lignées cellulaires de lymphome canin ont nécessité des concentrations plus élevées de lomustine pour inhiber de 50 % la croissance cellulaire, mais leur sensibilité au médicament augmenta lorsqu'elles furent mises en culture avec un inhibiteur de MGMT. Une épreuve fluorométrique des oligonucléotides et une épreuve d'amplification en chaîne par la polymérase en temps réel sur ces lignées cellulaires ont révélé, respectivement, une activité MGMT et une expression élevée d'ARNm de MGMT. Nous avons analysé le statut de méthylation des ilots CpG du gène MGMT canin par la méthode de séquençage au bisulfite. Contrairement aux cellules humaines, les lignées cellulaires canines de lymphome n'ont pas montré de corrélation significative entre le statut de méthylation et les niveaux de suppression de MGMT. Nos résultats suggèrent que lors de lymphome canin l'activité de MGMT peut influencer la sensibilité aux produits nitroso-urée; ainsi, l'inhibition de l'activité MGMT bénéficierait les patients résistants au nitroso-urée. Des études additionnelles sont nécessaires pour élucider le mécanisme de régulation de l'expression de MGMT.(Traduit par Docteur Serge Messier).


Assuntos
Metilases de Modificação do DNA/metabolismo , Doenças do Cão/enzimologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Linfoma/veterinária , Animais , Antineoplásicos/farmacologia , Ilhas de CpG , Metilases de Modificação do DNA/genética , Doenças do Cão/genética , Doenças do Cão/metabolismo , Cães , Lomustina/farmacologia , Linfoma/enzimologia , Linfoma/genética , Linfoma/metabolismo
17.
J Vet Med Sci ; 77(11): 1405-12, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26050843

RESUMO

Hypoxic conditions in various cancers are believed to relate with their malignancy, and hypoxia inducible factor-1α (HIF-1α) has been shown to be a major regulator of the response to low oxygen. In this study, we examined HIF-1α expression in canine lymphoma using cell lines and clinical samples and found that these cells expressed HIF-1α. Moreover, the HIF-1α inhibitors, echinomycin, YC-1 and 2-methoxyestradiol, suppressed the proliferation of canine lymphoma cell lines. In a xenograft model using NOD/scid mice, echinomycin treatment resulted in a dose-dependent regression of the tumor. Our results suggest that HIF-1α contributes to the proliferation and/or survival of canine lymphoma cells. Therefore, HIF-1α inhibitors may be potential agents to treat canine lymphoma.


Assuntos
Equinomicina/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Linfoma/veterinária , Animais , Linhagem Celular Tumoral , Doenças do Cão , Cães , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Linfoma/metabolismo , Camundongos , Neoplasias Experimentais/tratamento farmacológico
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