Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.494
Filtrar
1.
PLoS One ; 15(9): e0239542, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970763

RESUMO

The Australian Terrier breed is the breed at highest risk for naturally-occurring diabetes mellitus in the United States, where it is 32 times more likely to develop diabetes compared to mixed breed dogs. However, the heritability and mode of inheritance of spontaneous diabetes in Australian Terriers has not been reported. The aim of this study was therefore to investigate the heritability and mode of inheritance of diabetes in Australian Terriers. A cohort of related Australian Terriers including 383 Australian Terriers without diabetes, 86 Australian Terriers with spontaneous diabetes, and 14 Australian Terriers with an unknown phenotype, was analyzed. A logistic regression model including the effects of sex was formulated to evaluate the heritability of diabetes. The inheritance pattern of spontaneous diabetes in Australian Terriers was investigated by use of complex segregation analysis. Six possible inheritance models were studied, and the Akaike Information Criterion was used to determine the best model for diabetes inheritance in Australian Terriers, among the models deemed biologically feasible. Heritability of diabetes in Australian Terriers was estimated at 0.18 (95% confidence interval 0.0-0.67). There was no significant difference in the effect of males and females on disease outcome. Complex segregation analysis suggested that the mode of diabetes inheritance in Australian Terriers is polygenic, with no evidence for a large effect single gene influencing diabetes. It is concluded that in the population of Australian Terriers bred in the United States, a relatively small degree of genetic variation contributes to spontaneous diabetes. A genetic uniformity for diabetes-susceptible genes within the population of Australian Terriers bred in the Unites States could increase the risk of diabetes in this cohort. These findings hold promise for future genetic studies of canine diabetes focused on this particular breed.


Assuntos
Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Diabetes Mellitus/veterinária , Animais , Cruzamento , Doenças do Cão/epidemiologia , Doenças do Cão/genética , Cães , Feminino , Predisposição Genética para Doença/genética , Masculino , Linhagem , Estados Unidos
2.
PLoS One ; 15(8): e0238183, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857815

RESUMO

Lymphoma (lymphosarcoma) is the second most frequent cancer in dogs and is clinically comparable to human non-Hodgkin lymphoma. Factors affecting canine lymphoma progression are unknown and complex, but there is evidence that genetic mutations play an important role. We employed Next Gen DNA sequencing of six dogs with multicentric B-cell lymphoma undergoing CHOP chemotherapy to identify genetic variations potentially impacting response. Paired samples from non-neoplastic tissue (blood mononuclear cells) and lymphoma were collected at the time of diagnosis. Cases with progression free survival above the median of 231 days were grouped as 'good' responders and cases below the median were categorized as 'poor' responders. The average number of variants found was 17,138 per case. The variants were filtered to examine those with predicted moderate or high impacts. Many of the genes with variants had human orthologs with links to cancer, but the majority of variants were not previously reported in canine or human lymphoma. Seven genes had variants found in the cancers of at least two 'poor' responders but in no 'good' responders: ATRNL1, BAIAP2L2, ZNF384, ST6GALNAC5, ENSCAFG00000030179 (human ortholog: riboflavin kinase RFK), ENSCAFG00000029320, and ENSCAFG00000007370 (human ortholog: immunoglobin IGKV4-1). Two genes had variants found in the cancers of at least two 'good' responders but in no 'poor' responders: COX18 and ENSCAFG00000030512. ENSCAFG00000030512 has no reported orthologue in any other species. The role of these mutations in the progression of canine lymphoma requires further functional analyses and larger scale study.


Assuntos
Doenças do Cão/genética , Linfoma de Células B/veterinária , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Biomarcadores Tumorais/genética , Ciclofosfamida/administração & dosagem , Doenças do Cão/tratamento farmacológico , Cães , Doxorrubicina/administração & dosagem , Variação Genética , Estimativa de Kaplan-Meier , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/genética , Prednisolona/administração & dosagem , Resultado do Tratamento , Vincristina/administração & dosagem , Sequenciamento Completo do Genoma
3.
Nat Commun ; 11(1): 3059, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546718

RESUMO

Autonomous replication and segregation of mitochondrial DNA (mtDNA) creates the potential for evolutionary conflict driven by emergence of haplotypes under positive selection for 'selfish' traits, such as replicative advantage. However, few cases of this phenomenon arising within natural populations have been described. Here, we survey the frequency of mtDNA horizontal transfer within the canine transmissible venereal tumour (CTVT), a contagious cancer clone that occasionally acquires mtDNA from its hosts. Remarkably, one canine mtDNA haplotype, A1d1a, has repeatedly and recently colonised CTVT cells, recurrently replacing incumbent CTVT haplotypes. An A1d1a control region polymorphism predicted to influence transcription is fixed in the products of an A1d1a recombination event and occurs somatically on other CTVT mtDNA backgrounds. We present a model whereby 'selfish' positive selection acting on a regulatory variant drives repeated fixation of A1d1a within CTVT cells.


Assuntos
DNA Mitocondrial/genética , Doenças do Cão/genética , Haplótipos , Tumores Venéreos Veterinários/genética , Animais , Cães , Transferência Genética Horizontal , Filogenia , Polimorfismo Genético , Recidiva , Seleção Genética
4.
Immunogenetics ; 72(5): 315-323, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32556497

RESUMO

Canine atopic dermatitis (CAD) is an inflammatory and pruritic allergic skin disease with both genetic and environmental risk factors described. We performed mRNA sequencing of non-lesional axillary skin biopsies from nine German shepherd dogs. Obtained RNA sequences were mapped to the dog genome (CanFam3.1) and a high-quality skin transcriptome was generated with 23,510 expressed gene transcripts. Differentially expressed genes (DEGs) were defined by comparing three controls to five treated CAD cases. Using a leave-one-out analysis, we identified seven DEGs: five known to encode proteins with functions related to an activated immune system (CD209, CLEC4G, LOC102156842 (lipopolysaccharide-binding protein-like), LOC480601 (regakine-1-like), LOC479668 (haptoglobin-like)), one (OBP) encoding an odorant-binding protein potentially connected to rhinitis, and the last (LOC607095) encoding a novel long non-coding RNA. Furthermore, high mRNA expression of inflammatory genes was found in axillary skin from an untreated mild CAD case compared with healthy skin. In conclusion, we define genes with different expression patterns in CAD case skin helping us understand post-treatment atopic skin. Further studies in larger sample sets are warranted to confirm and to transfer these results into clinical practice.


Assuntos
Dermatite Atópica/veterinária , Doenças do Cão/genética , Regulação da Expressão Gênica/imunologia , Pele/imunologia , Animais , Dermatite Atópica/genética , Dermatite Atópica/imunologia , Doenças do Cão/imunologia , Cães , Inflamação/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma
5.
PLoS One ; 15(5): e0232900, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32413090

RESUMO

Congenital deafness in the domestic dog is usually related to the presence of white pigmentation, which is controlled primarily by the piebald locus on chromosome 20 and also by merle on chromosome 10. Pigment-associated deafness is also seen in other species, including cats, mice, sheep, alpacas, horses, cows, pigs, and humans, but the genetic factors determining why some piebald or merle dogs develop deafness while others do not have yet to be determined. Here we perform a genome-wide association study (GWAS) to identify regions of the canine genome significantly associated with deafness in three dog breeds carrying piebald: Dalmatian, Australian cattle dog, and English setter. We include bilaterally deaf, unilaterally deaf, and matched control dogs from the same litter, phenotyped using the brainstem auditory evoked response (BAER) hearing test. Principal component analysis showed that we have different distributions of cases and controls in genetically distinct Dalmatian populations, therefore GWAS was performed separately for North American and UK samples. We identified one genome-wide significant association and 14 suggestive (chromosome-wide) associations using the GWAS design of bilaterally deaf vs. control Australian cattle dogs. However, these associations were not located on the same chromosome as the piebald locus, indicating the complexity of the genetics underlying this disease in the domestic dog. Because of this apparent complex genetic architecture, larger sample sizes may be needed to detect the genetic loci modulating risk in piebald dogs.


Assuntos
Surdez/veterinária , Doenças do Cão/genética , Animais , Estudos de Casos e Controles , Surdez/congênito , Surdez/genética , Cães , Potenciais Evocados Auditivos , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Testes Auditivos , Polimorfismo de Nucleotídeo Único , Seleção Artificial , Pigmentação da Pele/genética
6.
Am J Vet Res ; 81(4): 355-360, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228257

RESUMO

OBJECTIVE: To measure expression of microRNAs (miRNAs) in plasma and in extracellular vesicles (EVs) derived from plasma for dogs with glioma and dogs with other brain diseases. SAMPLE: Plasma samples from 11 dogs with glioma and 19 control dogs with various other brain diseases. PROCEDURES: EVs were isolated from plasma samples by means of ultracentrifugation. Expression of 4 candidate reference miRNAs (let-7a, miR-16, miR-26a, and miR-103) and 4 candidate target miRNAs (miR-15b, miR-21, miR-155, and miR-342-3p) was quantified with reverse transcription PCR assays. Three software programs were used to select the most suitable reference miRNAs from among the 4 candidate reference miRNAs. Expression of the 4 target miRNAs was then calculated relative to expression of the reference genes in plasma and EVs, and relative expression was compared between dogs with glioma and control dogs with other brain diseases. RESULTS: The most suitable reference miRNAs were miR-16 for plasma and let-7a for EVs. Relative expression of miR-15b in plasma and in EVs was significantly higher in dogs with glioma than in control dogs. Relative expression of miR-342-3p in EVs was significantly higher in dogs with glioma than in control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that miR-15b and miR-342-3p have potential as noninvasive biomarkers for differentiating glioma from other intracranial diseases in dogs. However, more extensive analysis of expression in specific glioma subtypes and grades, compared with expression in more defined control populations, will be necessary to assess their clinical relevance.


Assuntos
Encefalopatias/veterinária , Doenças do Cão , Vesículas Extracelulares , Glioma/veterinária , MicroRNAs , Animais , Doenças do Cão/genética , Cães , Plasma
7.
PLoS One ; 15(4): e0232365, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32330187

RESUMO

Circulating tumor DNA (ctDNA), which carries tumor-specific mutations, is an emerging candidate biomarker for malignancies and for monitoring disease status in various human tumors. Recently, BRAF V595E mutation has been reported in 80% of dogs with urothelial carcinoma. This study investigates the BRAF V595E allele concentration in circulating cell-free DNA (cfDNA) and assesses the clinical significance of BRAF-mutated ctDNA levels in canines with urothelial carcinoma. A total of 15 dogs with urothelial carcinoma were included. cfDNA concentration was measured using a real-time polymerase chain reaction (PCR) of the LINE-1 gene. To measure the concentration of the mutated BRAF gene in cfDNA, allele-specific real-time PCR with a locked nucleic acid probe was performed. BRAF mutations were detected in 11 (73%) of the 15 tested tumor samples. BRAF-mutated ctDNA concentrations were significantly higher in dogs with the BRAF mutation (14.05 ± 13.51 ng/ml) than in wild-type dogs (0.21 ± 0.41 ng/ml) (p = 0.031). The amount of BRAF-mutated ctDNA in plasma increased with disease progression and responded to treatment. Our results show that BRAF-mutated ctDNA can be detected using allele-specific real-time PCR in plasma samples of canines with urothelial carcinoma with the BRAF V595E mutation. This ctDNA analysis may be a potentially useful tool for monitoring the progression of urothelial carcinoma and its response to treatment.


Assuntos
Carcinoma de Células de Transição/veterinária , Ácidos Nucleicos Livres/sangue , Doenças do Cão/genética , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Urológicas/veterinária , Alelos , Animais , Biomarcadores Tumorais/sangue , Carcinoma de Células de Transição/sangue , Carcinoma de Células de Transição/genética , DNA de Neoplasias/sangue , Doenças do Cão/sangue , Cães , Feminino , Masculino , Proteínas Proto-Oncogênicas B-raf/sangue , Neoplasias Urológicas/sangue , Neoplasias Urológicas/genética
8.
Can Vet J ; 61(4): 396-400, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32255825

RESUMO

Gastric carcinoma is not commonly reported in dogs. There is an increased risk, however, in certain breeds such as the Belgian Tervuren. Review of the Veterinary Medical Database (VMDB) established an increase in risk for gastric carcinoma in the chow chow breed. In 106 chow chow dogs signs commenced, on average, 3 weeks before definitive diagnosis. The most common clinical signs were vomiting, loss of appetite, diarrhea, and melena. Most affected dogs were euthanized, without treatment, within 2 weeks of diagnosis. Two dogs which were treated aggressively (surgery and chemotherapy) survived a considerably longer time (12 and 36 months). Histologically, these chow chow dogs comprised a similar histologic type as familial gastric carcinoma in humans; diffuse-type carcinoma that was enriched in the signet ring and mucinous variants. Understanding the pathogenesis of diffuse gastric carcinoma in the chow chow dog may provide insight into the biology of this aggressive cancer in humans.


Assuntos
Adenocarcinoma/veterinária , Doenças do Cão/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/veterinária , Animais , Cruzamento , Cães
9.
Res Vet Sci ; 131: 7-14, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278962

RESUMO

Melanoma progression is associated with the epithelial-mesenchymal transition (EMT) when tumor cells reduce E-cadherin and increase N-cadherin expression resulting in an escape from the microenvironment via loss of cellular adhesion and gain of motility. Transcription factor proteins Snail and ZEB trigger EMT by repression of epithelial markers and activation of mesenchymal properties. This study evaluated E-cadherin, N-cadherin, Snail, ZEB1 and ZEB2 expression by IHC and investigated their relationship with morphological characteristics in cutaneous and oral canine melanoma. Results from melanoma cases demonstrated E-cadherin expression in 45% (9/20) of oral and 58% (22/38) of cutaneous tumors, while N-cadherin expression was observed in 95% (18/19) of oral and 92% (34/37) of cutaneous melanoma. Cytoplasmic and nuclear N-cadherin expression was positively correlated with ZEB1 expression, while the cell membrane N-cadherin expression was positively correlated with ZEB2. In addition, an increase in nuclear N-cadherin expression was associated with reduced Snail expression in cutaneous melanoma and an increase in Snail expression in oral melanoma, indicating that the correlation between N-cadherin and Snail expression is coincident with tumor location. Our data suggest that ZEB family protein is associated with N-cadherin translocation from cell membrane to the cytoplasm and nuclei, and may act as important transcription factors of EMT regulation in canine melanoma.


Assuntos
Doenças do Cão/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Melanoma/veterinária , Neoplasias Cutâneas/veterinária , Fatores de Transcrição da Família Snail/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Animais , Caderinas/metabolismo , Adesão Celular , Movimento Celular , Doenças do Cão/genética , Cães , Regulação Neoplásica da Expressão Gênica , Humanos , Melanoma/metabolismo , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Neoplasias Bucais/veterinária , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição/metabolismo , Microambiente Tumoral , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
10.
PLoS One ; 15(3): e0230272, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32168360

RESUMO

Canine prostate adenocarcinoma (PAC) and transitional cell carcinoma (TCC) of prostate and urinary bladder are highly invasive and metastatic tumors of closely neighbored organs. Cell lines are valuable tools to investigate tumor mechanisms and therapeutic approaches in vitro. PAC in dogs is infrequent, difficult to differentiate from TCC and usually characterized by poor prognosis, enhancing the value of the few available cell lines. However, as cell lines adapt to culturing conditions, a thorough characterization, ideally compared to original tissue, is indispensable. Herein, six canine PAC cell lines and three TCC cell lines were profiled by immunophenotype in comparison to respective original tumor tissues. Three of the six PAC cell lines were derived from primary tumor and metastases of the same patient. Further, two of the three TCC cell lines were derived from TCCs invading into or originating from the prostate. Cell biologic parameters as doubling times and chemoresistances to commonly used drugs in cancer treatment (doxorubicin, carboplatin and meloxicam) were assessed. All cell lines were immunohistochemically close to the respective original tissue. Compared to primary tumor cell lines, metastasis-derived cell lines were more chemoresistant to doxorubicin, but equally susceptive to carboplatin treatment. Two cell lines were multiresistant. COX-2 enzyme activity was demonstrated in all cell lines. However, meloxicam inhibited prostaglandin E2 production in only seven of nine cell lines and did neither influence metabolic activity, nor proliferation. The characterized nine cell lines represent excellent tools to investigate PAC as well as TCC in prostate and urinary bladder of the dog. Furthermore, the profiled paired cell lines from PAC primary tumor and metastasis provide the unique opportunity to investigate metastasis-associated changes PAC cells undergo in tumor progression. The combination of nine differently chemoresistant PAC and TCC cell lines resembles the heterogeneity of canine lower urinary tract cancer.


Assuntos
Adenocarcinoma/patologia , Carcinoma de Células de Transição/patologia , Neoplasias da Próstata/patologia , Neoplasias da Bexiga Urinária/patologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Animais , Carboplatina/farmacologia , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/imunologia , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/imunologia , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Doenças do Cão/tratamento farmacológico , Doenças do Cão/genética , Doenças do Cão/imunologia , Doenças do Cão/patologia , Cães , Doxorrubicina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Imunofenotipagem , Masculino , Meloxicam/farmacologia , Metástase Neoplásica , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/imunologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/imunologia
11.
PLoS Genet ; 16(3): e1008659, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32150541

RESUMO

Retinitis pigmentosa (RP) is the leading cause of blindness with nearly two million people affected worldwide. Many genes have been implicated in RP, yet in 30-80% of the RP patients the genetic cause remains unknown. A similar phenotype, progressive retinal atrophy (PRA), affects many dog breeds including the Miniature Schnauzer. We performed clinical, genetic and functional experiments to identify the genetic cause of PRA in the breed. The age of onset and pattern of disease progression suggested that at least two forms of PRA, types 1 and 2 respectively, affect the breed, which was confirmed by genome-wide association study that implicated two distinct genomic loci in chromosomes 15 and X, respectively. Whole-genome sequencing revealed a fully segregating recessive regulatory variant in type 1 PRA. The associated variant has a very recent origin based on haplotype analysis and lies within a regulatory site with the predicted binding site of HAND1::TCF3 transcription factor complex. Luciferase assays suggested that mutated regulatory sequence increases expression. Case-control retinal expression comparison of six best HAND1::TCF3 target genes were analyzed with quantitative reverse-transcriptase PCR assay and indicated overexpression of EDN2 and COL9A2 in the affected retina. Defects in both EDN2 and COL9A2 have been previously associated with retinal degeneration. In summary, our study describes two genetically different forms of PRA and identifies a fully penetrant variant in type 1 form with a possible regulatory effect. This would be among the first reports of a regulatory variant in retinal degeneration in any species, and establishes a new spontaneous dog model to improve our understanding of retinal biology and gene regulation while the affected breed will benefit from a reliable genetic testing.


Assuntos
Doenças do Cão/genética , Degeneração Retiniana/genética , Retinite Pigmentosa/genética , Animais , Estudos de Casos e Controles , Colágeno Tipo IX/genética , Colágeno Tipo IX/metabolismo , Cães , Endotelina-2/genética , Endotelina-2/metabolismo , Feminino , Mutação da Fase de Leitura/genética , Estudo de Associação Genômica Ampla/métodos , Haplótipos/genética , Masculino , Modelos Animais , Mutação/genética , Linhagem , Fenótipo , Retina/metabolismo , Retinite Pigmentosa/metabolismo
12.
Immunogenetics ; 72(4): 241-250, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32219493

RESUMO

Canine atopic dermatitis (AD) is a very common inflammatory skin disease, but limited data are available on the genetic characterization (somatic mutations, microarrays, and genome-wide association study (GWAS)) of skin lesions in affected dogs. microRNAs are good biomarkers in inflammatory and neoplastic diseases in people. The aim of this study was to evaluate microRNA expression in the skin of atopic beagles, before and after exposure to Dermatophagoides farinae. Four atopic and four unrelated age-matched healthy beagle dogs were enrolled. Total RNA was extracted from flash-frozen skin biopsies of healthy and atopic dogs. For the atopic dogs, skin biopsies were taken from non-lesional (day 0) and lesional skin (day 28 of weekly environmental challenge with Dermatophagoides farinae). Small RNA libraries were constructed and sequenced. The microRNA sequences were aligned to CanFam3.1 genome. Differential expressed microRNAs were selected on the basis of fold-change and statistical significance (fold-change ≥ 1.5 and p ≤ 0.05 as thresholds. A total of 277 microRNAs were sequenced. One hundred and twenty-one differentially regulated microRNAs were identified between non-lesional and healthy skin. Among these, two were increased amount and 119 were decreased amount. A total of 45 differentially regulated microRNAs between lesional and healthy skin were identified, 44 were decreased amount and one was increased amount. Finally, only two increased amount microRNAs were present in lesional skin when compared with that of non-lesional skin. This is the first study in which dysregulation of microRNAs has been associated with lesional and non-lesional canine AD. Larger studies are needed to understand the role of microRNA in canine AD.


Assuntos
Dermatite Atópica/genética , Doenças do Cão/genética , MicroRNAs/genética , Animais , Estudos de Casos e Controles , Dermatite Atópica/patologia , Dermatophagoides farinae/patogenicidade , Cães , Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Reprodutibilidade dos Testes , Pele/patologia
13.
PLoS One ; 15(3): e0229728, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210430

RESUMO

Angiosarcoma (AS) is a rare neoplasm with limited treatment options and a poor survival rate. Development of effective therapies is hindered by the rarity of this disease. Dogs spontaneously develop hemangiosarcoma (HSA), a common, histologically similar neoplasm. Metastatic disease occurs rapidly and despite chemotherapy, most dogs die several months after diagnosis. These features suggest that HSA might provide a tractable model to test experimental therapies in clinical trials. We previously reported whole exome sequencing of 20 HSA cases. Here we report development of a NGS targeted resequencing panel to detect driver mutations in HSA and other canine tumors. We validated the panel by resequencing the original 20 cases and sequenced 30 additional cases. Overall, we identified potential driver mutations in over 90% of the cases, including well-documented (in human cancers) oncogenic mutations in PIK3CA (46%), PTEN (6%), PLCG1(4%), and TP53 (66%), as well as previously undetected recurrent activating mutations in NRAS (24%). The driver role of these mutations is further demonstrated by augmented downstream signaling crucial to tumor growth. The recurrent, mutually exclusive mutation patterns suggest distinct molecular subtypes of HSA. Driver mutations in some subtypes closely resemble those seen in some AS cases, including NRAS, PLCG1, PIK3CA and TP53. Furthermore, activation of the MAPK and PI3K pathways appear to be key oncogenic mechanisms in both species. Together, these observations suggest that dogs with spontaneous HSA could serve as a useful model for testing the efficacy of targeted therapies, some of which could potentially be of therapeutic value in AS.


Assuntos
Doenças do Cão/genética , Hemangiossarcoma/veterinária , Animais , Cães , Exoma/genética , Genes Neoplásicos , Hemangiossarcoma/genética , Humanos , Mutação/genética , Fosfatidilinositol 3-Quinases/genética , Reprodutibilidade dos Testes , Transdução de Sinais/genética , Sequenciamento Completo do Exoma , Proteínas ras/genética
14.
PLoS One ; 15(3): e0225901, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32119674

RESUMO

Hereditary nasal parakeratosis (HNPK) is an inherited disorder described in Labrador Retrievers and Greyhounds. It has been associated with breed-specific variants in the SUV39H2 gene encoding a histone 3 methyltransferase involved in epigenetic silencing. Formalin-fixed biopsies of the nasal planum of Labrador Retrievers were screened by immunofluorescence microscopy for the presence and distribution of epidermal proliferation and differentiation markers. Gene expression of these markers was further analysed using RNA sequencing (RNA-seq) and ultrastructural epidermal differences were investigated by electron microscopy. Differentiation of the nasal planum in the basal and suprabasal epidermal layers of HNPK-affected dogs (n = 6) was similar compared to control dogs (n = 6). In the upper epidermal layers, clear modifications were noticed. Loricrin protein was absent in HNPK-affected nasal planum sections in contrast to sections of the same location of control dogs. However, loricrin was present in the epidermis of paw pads and abdominal skin from HNPK dogs and healthy control dogs. The patterns of keratins K1, K10 and K14, were not markedly altered in the nasal planum of HNPK-affected dogs while the expression of the terminal differentiation marker involucrin appeared less regular. Based on RNA-seq, LOR and IVL expression levels were significantly decreased, while KRT1, KRT10 and KRT14 levels were up-regulated (log2fold-changes of 2.67, 3.19 and 1.71, respectively) in HNPK-affected nasal planum (n = 3) compared to control dogs (n = 3). Electron microscopical analysis revealed structural alterations in keratinocytes and stratum corneum, and disrupted keratinocyte adhesions and distended intercellular spaces in lesional samples (n = 3) compared to a sample of a healthy control dog (n = 1). Our findings demonstrate aberrant keratinocyte terminal differentiation of the nasal planum of HNPK-affected Labrador Retrievers and provide insights into biological consequences of this inactive SUV39H2 gene variant.


Assuntos
Antígenos de Diferenciação , Doenças do Cão , Doenças Genéticas Inatas , Doenças Nasais , Paraceratose , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Doenças do Cão/genética , Doenças do Cão/metabolismo , Doenças do Cão/patologia , Cães , Feminino , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/metabolismo , Doenças Genéticas Inatas/patologia , Doenças Genéticas Inatas/veterinária , Queratinócitos/metabolismo , Queratinócitos/patologia , Masculino , Doenças Nasais/genética , Doenças Nasais/metabolismo , Doenças Nasais/patologia , Doenças Nasais/veterinária , Paraceratose/genética , Paraceratose/metabolismo , Paraceratose/patologia , Paraceratose/veterinária
15.
Invest Ophthalmol Vis Sci ; 61(3): 11, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32176262

RESUMO

Purpose: To define remodeling of photoreceptor synaptic terminals and second-order retinal neurons in canine X-linked progressive retinal atrophy 1 caused by a five-nucleotide deletion in the RPGR exon ORF15. Methods: Retinas of normal and mutant dogs were used for gene expression, Western blot, and immunohistochemistry. Cell-specific markers were used to examine disease-dependent retinal remodeling. Results: In mutant retinas, a number of rod axon terminals retract into the outer nuclear layer. This neuritic atrophy preceded significant loss of rods and was evident early in disease. Rod bipolar and horizontal cell processes were found to extend into the outer nuclear layer, where they seemed to form contacts with the spherules of rod photoreceptors. No ectopic rewiring was observed. Because cytoskeletal reorganization was previously shown to underlie photoreceptor axon retraction, we examined normal and mutant retinas for expression of axon guidance receptors ROBO1 and ROBO2, which are known to regulate actin cytoskeleton dynamics. We found that the overall expression of both ROBO1 and ROBO2 is retained at the same level in premature and fully developed normal retinas. However, analysis of predisease and early disease retinas identified markedly decreased levels of ROBO1 in rod spherules compared with controls. In contrast, no differences in ROBO1 signals were noted in cone pedicles in normal and mutant retinas, where ROBO1 levels remained similarly low. Conclusions: Depletion of ROBO1 in rod synaptic terminals correlates with the remodeling of axonal and dendritic processes in the outer retina of dogs with X-linked progressive retinal atrophy 1 and may play a role in the retraction of rod axons.


Assuntos
Doenças do Cão/metabolismo , Doenças Genéticas Ligadas ao Cromossomo X/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Terminações Pré-Sinápticas/metabolismo , Receptores Imunológicos/metabolismo , Degeneração Retiniana/metabolismo , Animais , Orientação de Axônios/fisiologia , Axônios/patologia , Doenças do Cão/genética , Doenças do Cão/patologia , Cães , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Doenças Genéticas Ligadas ao Cromossomo X/veterinária , Microscopia Confocal , Proteínas do Tecido Nervoso/deficiência , Plasticidade Neuronal/fisiologia , Terminações Pré-Sinápticas/patologia , Receptores Imunológicos/deficiência , Retina/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/patologia , Degeneração Retiniana/veterinária , Neurônios Retinianos/metabolismo , Neurônios Retinianos/patologia , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/patologia
16.
Res Vet Sci ; 130: 33-40, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32114248

RESUMO

INTRODUCTION: Canine allergic conjunctivitis (cAC) is described as the most frequent ocular manifestation associated with canine atopic dermatitis (cAD). OBJECTIVES: Clinical and immunological characterization of cAD through IL-6, TNF-α and IL-12 mRNA expression quantification in canine conjunctivae. PROCEDURES: Twenty client-owned dogs with both cAC and cAD and twenty-one healthy controls were enrolled and clinician assessed CADESI-04 and grade of ocular signs were calculated. Conjunctival biopsies were performed on all animals and relative quantification of the interleukins mRNA expression performed by qRT-PCR. The correlation between cytokine gene expression and cAC score was evaluated, as well as CADESI-04 values. RESULTS: The qRT-PCR showed a significant gene upregulation of respectively 291.48 (p = 1.306e-09) and 4.85 (p = .00033) folds on IL-6 and IL-12 in dogs with allergic conjunctivitis compared to the control group. Regarding the average expression of TNF-α there were no statistical significant differences between both groups (p = .18). Higher cAC scores were associated with enhanced gene expression of TNF-α and IL-12. No correlation was found between the cytokine gene expression levels and the CADESI-04 values. CONCLUSION: An increase of IL6 and IL12 in cAC was found in the studied population. These two cytokines may be potential immunotherapy targets cAC classification.


Assuntos
Conjuntivite Alérgica/veterinária , Citocinas/genética , Doenças do Cão/genética , Expressão Gênica , Animais , Conjuntivite Alérgica/genética , Conjuntivite Alérgica/imunologia , Citocinas/metabolismo , Cães , Feminino , Masculino
17.
Res Vet Sci ; 130: 93-97, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32155472

RESUMO

Cutaneous papilloma (CP) and cutaneous squamous cell carcinoma (CSCC) are frequent epidermal tumours in dogs. In this regard, the study of the deregulated activity of signalling molecules during the epidermal tumourigenesis process could be the basis for the development of novel molecular mechanism-based antitumour treatments for CP and CSCC canine patients. Recent evidence suggests that the development and progression of CP and CSCC involve the dysregulated activation of the Hippo signalling pathway effector YAP. Thus, in the present study, we evaluated the immunohistochemical expression pattern of YAP in sections of tissue microarrays constructed from canine samples of normal epidermis, CP, preneoplastic epidermis, and CSCC. In samples of CP, preneoplastic epidermis, and CSCC, YAP expression was significantly increased relative to normal epidermis. This emerging evidence suggests that the dysregulated activity of the Hippo signalling pathway effector YAP represents a frequent event during canine epidermal tumourigenesis, pointing to this protein as a potential therapeutic target for the treatment of CP and CSCC in dogs.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Carcinogênese/genética , Carcinoma de Células Escamosas/veterinária , Doenças do Cão/genética , Epiderme/patologia , Papiloma/veterinária , Neoplasias Cutâneas/veterinária , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Carcinoma de Células Escamosas/genética , Cães , Perfilação da Expressão Gênica/veterinária , Papiloma/genética , Transdução de Sinais , Neoplasias Cutâneas/genética , Análise Serial de Tecidos
18.
Res Vet Sci ; 130: 197-202, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32200159

RESUMO

Mammary tumors represent the second most common neoplasia in the canine species, where more than 50% of the cases are classified as malignant. The histological classification is used as a prognostic tool. Cadherins and catenins are responsible for cell adhesion and are intrinsic connected with the process of metastasis. E-cadherin expression in canine mammary tissues have been extensively studied. However, the studies with catenins are still scarce in the canine species. This study evaluated 74 canine mammary tissues by assessing the expression of E-cadherin and α, ß and P-120 catenin molecules using the immunohistochemistry technique and their relationship with clinicopathological parameters. Three patterns of expression were identified in this study: membranous, cytoplasmic and both (membranous and cytoplasmic). In benign tumors, more than 80% of the cases had preserved expression and in malignant tumors 20% of the cases had reduced expression. A correlation between E-cadherin and P-120-catenin expression was found as well as a significant relationship between the histological type and the expression of α-catenin in malignant tumors.


Assuntos
Caderinas/metabolismo , Cateninas/metabolismo , Doenças do Cão/genética , Neoplasias Mamárias Animais/genética , alfa Catenina/metabolismo , beta Catenina/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Doenças do Cão/patologia , Cães , Feminino , Imuno-Histoquímica/veterinária , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Animais/patologia
19.
Vet Parasitol ; 280: 109063, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32151890

RESUMO

The proliferation of Demodex mites is mainly controlled by host immunity; however, the precised mechanism of host-mite interplay and host immune response in the cutaneous microenvironment of dogs with generalized demodicosis (GD) are not yet established. In the present study, we envisaged the alterations in the expression of toll-like receptors (TLRs) and immuno-regulatory cytokine gene in the skin lesions and peripheral blood mononuclear cells (PBMCs) of dogs with GD. The expression of TLR2, TLR6, IFN-γ, TGF-ß and IL-10 genes in the skin lesions and PBMCs of 15 dogs with GD was quantified by qRT-PCR. Compared to healthy dogs, significantly elevated expression of TLR2 (P = 0.048), TGF-ß (P = 0.04) and IL-10 (P = 0.012) were found in the PBMCs of dogs with GD. Conversely, there was significantly reduced expression of TLR6 gene (P = 0.021) in the PBMCs of these dogs. The infested dogs also revealed significantly elevated expression of TLR2 gene (P = 0.034) in the skin lesions, while, the expression of the TLR6 gene was found to be significantly (P = 0.004) reduced. Interestingly, significant alterations in TGF-ß (P = 0.105) and IL-10 (P = 0.162) genes expression were not observed in the skin lesions of diseased dogs. Our findings suggest that Demodex mites contribute to a different systemic and cutaneous immune response in dogs for their proliferation, and consequently the development of GD. Therefore, Demodex mites might be inducing the immunosuppression through activating the systemic over-expression of immunosuppressive cytokines; however, in the cutaneous lesions, the expression of immunosuppressive cytokines remained unaltered. Both systemic and local over-expression of TLR2 and reduced expression of TLR6 genes might be responsible for the inflammatory signs of canine demodicosis and helping to the mite to escape the host immunity.


Assuntos
Citocinas/genética , Doenças do Cão/genética , Expressão Gênica/imunologia , Infestações por Ácaros/veterinária , Receptores Toll-Like/genética , Animais , Citocinas/imunologia , Doenças do Cão/imunologia , Cães , Infestações por Ácaros/genética , Infestações por Ácaros/imunologia , Dermatopatias Parasitárias/genética , Dermatopatias Parasitárias/imunologia , Dermatopatias Parasitárias/veterinária , Receptores Toll-Like/imunologia
20.
BMC Cancer ; 20(1): 251, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32209086

RESUMO

BACKGROUND: Invasive urothelial carcinoma (iUC) is highly similar between dogs and humans in terms of pathologic presentation, molecular subtypes, response to treatment and age at onset. Thus, the dog is an established and relevant model for testing and development of targeted drugs benefiting both canine and human patients. We sought to identify gene expression patterns associated with two primary types of canine iUC tumors: those that express a common somatic mutation in the BRAF gene, and those that do not. METHODS: We performed RNAseq on tumor and normal tissues from pet dogs. Analysis of differential expression and clustering, and positional and individual expression was used to develop gene set enrichment profiles distinguishing iUC tumors with and without BRAFV595E mutations, as well as genomic regions harboring excessive numbers of dysregulated genes. RESULTS: We identified two expression clusters that are defined by the presence/absence of a BRAFV595E (BRAFV600E in humans) somatic mutation. BRAFV595E tumors shared significantly more dysregulated genes than BRAF wild-type tumors, and vice versa, with 398 genes differentiating the two clusters. Key genes fall into clades of limited function: tissue development, cell cycle regulation, immune response, and membrane transport. The genomic site with highest number of dysregulated genes overall lies in a locus corresponding to human chromosome 8q24, a region frequently amplified in human urothelial cancers. CONCLUSIONS: These data identify critical sets of genes that are differently regulated in association with an activating mutation in the MAPK/ERK pathway in canine iUC tumors. The experiments also highlight the value of the canine system in identifying expression patterns associated with a common, shared cancer.


Assuntos
Carcinoma de Células de Transição/veterinária , Doenças do Cão/genética , Perfilação da Expressão Gênica/veterinária , Redes Reguladoras de Genes , Neoplasias da Bexiga Urinária/veterinária , Animais , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/patologia , Mapeamento Cromossômico , Cromossomos Humanos Par 8/genética , Doenças do Cão/patologia , Cães , Feminino , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Mutação , Estadiamento de Neoplasias , Proteínas Proto-Oncogênicas B-raf/genética , Análise de Sequência de RNA/veterinária , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA