Evaluation of cell proliferation and apoptosis markers as predictive factors for electrochemotherapy in cutaneous squamous cell carcinoma of cats

ABSTRACT: Determining cell proliferation rates and tumor apoptosis through immunohistochemistry allows the evaluation of the biological behavior of the tumor, optimizing the patient’s clinical course. This study aimed to analyze the immunohistochemical expression of Ki-67, COX-2 and caspase-3 and correlate them with the type of response to ECT in feline cutaneous squamous cell carcinoma (SCC), thus determining the predictive potential of these variables. For this, 13 samples of feline cutaneous SCC were evaluated before ECT, and statistical analyses of the correlation intensity between the variables were performed using the Spearman correlation coefficient, with a significance level of 95%. The results indicate a significant negative correlation between histopathological grade and response to ECT (ρ=-0.6; p=0.03); there was no significant correlation between Ki-67, COX-2 and caspase-3 immunoexpression with the response to ECT (ρ=-0.18; p=0.54/ρ=-0.23; p=0.44/ρ=-0.12; p=0.69, respectively). Therefore, the study shows that the histopathological grade, tumor size and staging, degree of cellular pleomorphism and degree of inflammatory infiltrate can be considered negative prognostic factors for cutaneous SCC and negative predictors for response to ECT. However, the markers Ki-67, COX-2 and caspase-3 are not considered predictive factors for the type of response to ECT. In addition, no relationship between these immunoexpressions and greater tumor aggressiveness was observed. The SCCs evaluated in this study showed significant COX-2 labeling, indicating a potential therapeutic target. ECT has been shown to be safe and effective for local control of feline cutaneous SCC but with reduced effectiveness in larger and invasive lesions

Retalho de padrão axial ilíaco circunflexo empregado após ressecção de hemangiopericitoma em cão - relato de caso

Os hemangiopericitomas fazem parte dos sarcomas de tecido mole, e correspondem a 14% das neoplasias mesenquimais em cães e gatos. Apresenta etiologia desconhecida, crescimento lento, aspecto infiltrativo e não metastático. Acometem principalmente animais de raças grandes, de meia idade a idosos e não apresenta predileção por raça e sexo. Os tratamentos mais indicados são a amputação, ressecção local associada à radioterapia e cirurgias reconstrutivas. O uso de técnicas cirúrgicas reconstrutivas, permite que o animal retorne sua rotina normal com maior rapidez e com resultados estéticos satisfatórios. O presente trabalho tem como objetivo relatar o emprego de retalho de padrão axial da artéria ilíaca circunflexa profunda após a ressecção de hemangiopericitoma em região de membro pélvico esquerdo de um cão. Esta modalidade de tratamento empregada no presente relato, juntamente com quimioterapia mostraram resultados satisfatórios, mantendo a funcionalidade do membro e qualidade de vida da paciente. Palavras-chave: cirurgia reconstrutiva, neoplasia, quimioterapia, canino

Method to obtain platelet-rich plasma from rabbits (Oryctolagus cuniculus )

Abstract: Platelet-rich plasma (PRP) is a product easy and inxpesnsive, and stands out to for its growth factors in tissue repair. To obtain PRP, centrifugation of whole blood is made with specific time and gravitational forces. Thus, the present work aimed to study a method of double centrifugation to obtain PRP in order to evaluate the effective increase of platelet concentration in the final product, the preparation of PRP gel, and to optimize preparation time of the final sample. Fifteen female White New Zealand rabbits underwent blood sampling for the preparation of PRP. Samples were separated in two sterile tubes containing sodium citrate. Tubes were submitted to the double centrifugation protocol, with lid closed and 1600 revolutions per minute (rpm) for 10 minutes, resulting in the separation of red blood cells, plasma with platelets and leucocytes. After were opened and plasma was pipetted and transferred into another sterile tube. Plasma was centrifuged again at 2000rpm for 10 minutes; as a result it was split into two parts: on the top, consisting of platelet-poor plasma (PPP) and at the bottom of the platelet button. Part of the PPP was discarded so that only 1ml remained in the tube along with the platelet button. This material was gently agitated to promote platelets resuspension and activated when added 0.3ml of calcium gluconate, resulting in PRP gel. Double centrifugation protocol was able to make platelet concentration 3 times higher in relation to the initial blood sample. The volume of calcium gluconate used for platelet activation was 0.3ml, and was sufficient to coagulate the sample. Coagulation time ranged from 8 to 20 minutes, with an average of 17.6 minutes. Therefore, time of blood centrifugation until to obtain PRP gel took only 40 minutes. It was concluded that PRP was successfully obtained by double centrifugation protocol, which is able to increase the platelet concentration in the sample compared with whole blood, allowing its use in surgical procedures. Furthermore, the preparation time is appropriate to obtain PRP in just 40 minutes, and calcium gluconate is able to promote the activation of platelets

Mitochondrial genetic diversity, selection and recombination in a canine transmissible cancer.

Canine transmissible venereal tumour (CTVT) is a clonally transmissible cancer that originated approximately 11,000 years ago and affects dogs worldwide. Despite the clonal origin of the CTVT nuclear genome, CTVT mitochondrial genomes (mtDNAs) have been acquired by periodic capture from transient hosts. We sequenced 449 complete mtDNAs from a global population of CTVTs, and show that mtDNA horizontal transfer has occurred at least five times, delineating five tumour clades whose distributions track two millennia of dog global migration. Negative selection has operated to prevent accumulation of deleterious mutations in captured mtDNA, and recombination has caused occasional mtDNA re-assortment. These findings implicate functional mtDNA as a driver of CTVT global metastatic spread, further highlighting the important role of mtDNA in cancer evolution.Wellcome Trust Investigator Award, 102942/Z/13/A Elizabeth P Murchison Leverhulme Trust Philip Leverhulme Prize Elizabeth P Murchison Royal Society Research Grant, RG130615 Elizabeth P Murchiso

Somatic evolution and global expansion of an ancient transmissible cancer lineage

Made available in DSpace on 2019-10-06T15:53:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-08-02GPD Charitable TrustLeverhulme TrustThe canine transmissible venereal tumor (CTVT) is a cancer lineage that arose several millennia ago and survives by “metastasizing” between hosts through cell transfer. The somatic mutations in this cancer record its phylogeography and evolutionary history. We constructed a time-resolved phylogeny from 546 CTVT exomes and describe the lineage's worldwide expansion. Examining variation in mutational exposure, we identify a highly context-specific mutational process that operated early in the cancer's evolution but subsequently vanished, correlate ultraviolet-light mutagenesis with tumor latitude, and describe tumors with heritable hyperactivity of an endogenous mutational process. CTVT displays little evidence of ongoing positive selection, and negative selection is detectable only in essential genes. We illustrate how long-lived clonal organisms capture changing mutagenic environments, and reveal that neutral genetic drift is the dominant feature of long-term cancer evolution.Transmissible Cancer Group Department of Veterinary Medicine University of CambridgeAnimal Management in Rural and Remote Indigenous Communities (AMRRIC)World VetsAnimal Shelter Stichting Dierenbescherming SurinameSikkim Anti-Rabies and Animal Health Programme Department of Animal Husbandry Livestock Fisheries and Veterinary Services Government of SikkimRoyal (Dick) School of Veterinary Studies Roslin Institute University of Edinburgh Easter Bush CampusConserLab Animal Preventive Medicine Department Faculty of Animal and Veterinary Sciences University of ChileCorozal Veterinary Hospital University of PanamáSt. George's UniversityNakuru District Veterinary Scheme LtdAnimal Medical CentreInternational Animal Welfare Training Institute UC Davis School of Veterinary MedicineCentro Universitário de Rio Preto (UNIRP)Department of Clinical and Veterinary Surgery São Paulo State University (UNESP)Ladybrand Animal ClinicVeterinary Clinic Sr. Dog'sWorld Vets Latin America Veterinary Training CenterNational Veterinary Research InstituteAnimal ClinicIntermunicipal Stray Animals Care Centre (DIKEPAZ)Animal Protection Society of SamoaFaculty of Veterinary Science University of ZuliaVeterinary Clinic BIOCONTROLFaculty of Veterinary Medicine School of Health Sciences University of ThessalyVeterinary Clinic El Roble Animal Healthcare Network Faculty of Animal and Veterinary Sciences University of ChileOnevetGroup Hospital Veterinário BernaUniversidade Vila VelhaVeterinary Clinic ZoovetservisÉcole Inter-états des Sciences et Médecine Vétérinaires de DakarDepartment of Small Animal Medicine Faculty of Veterinary Medicine Utrecht UniversityVetexpert Veterinary GroupVeterinary Clinic Lopez QuintanaClinique Veterinaire de Grand Fond Saint Gilles les BainsDepartment of Veterinary Sciences University of MessinaFacultad de Medicina Veterinaria y Zootecnia Universidad Autónoma del Estado de MéxicoSchool of Veterinary Medicine Universidad de las AméricasCancer Development and Innate Immune Evasion Lab Champalimaud Center for the UnknownTouray and Meyer Vet ClinicHillside Animal HospitalKampala Veterinary SurgeryAsavet Veterinary CharitiesVets Beyond BordersFaculty of Veterinary Medicine Autonomous University of YucatanLaboratorio de Patología Veterinaria Universidad de CaldasInterdisciplinary Centre of Research in Animal Health (CIISA) Faculty of Veterinary Medicine University of LisbonFour Paws InternationalHelp in SufferingVeterinary Clinic Dr José RojasDepartment of Biotechnology Balochistan University of Information Technology Engineering and Management SciencesCorozal Veterinary ClinicVeterinary Clinic VetmasterState Hospital of Veterinary MedicineJomo Kenyatta University of Agriculture and TechnologyLaboratory of Biomedicine and Regenerative Medicine Department of Clinical Sciences Faculty of Animal and Veterinary Sciences University of ChileFaculty of Veterinary and Agricultural Sciences University of MelbourneAnimal Anti Cruelty LeagueClinical Sciences Department Faculty of Veterinary Medicine BucharestDepartment of Pathology Faculty of Veterinary Medicine Ankara UniversityFaculty of Veterinary Sciences National University of AsuncionLilongwe Society for Protection and Care of Animals (LSPCA)Wellcome Sanger InstituteDepartment of Cellular and Molecular Medicine University of California San DiegoDepartment of Clinical and Veterinary Surgery São Paulo State University (UNESP)Leverhulme Trust: 102942/Z/13/

Recurrent horizontal transfer identifies mitochondrial positive selection in a transmissible cancer

Abstract: 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

Comparação de duas classificações histopatológicas com o padrão de imuno-marcação para KIT, a avaliação da proliferação celular e com a presença de mutações no c-KIT de mastocitomas cutâneos caninos

RESUMO: A graduação histopatológica é o método de eleição para prever o comportamento biológico do mastocitoma e, atualmente, são utilizados os métodos de Patnaik e de Kiupel para dividi-los em graus de malignidade. O objetivo do presente trabalho foi comparar as duas classificações histológicas com as variáveis clínicas, os marcadores imuno-histoquímicos e com a presença de mutações para verificar as características que estão mais relacionadas entre si e com os piores prognósticos. Foram avaliados 61 animais, levando em consideração o sexo, a raça, a idade, a localização tumoral, o grau tumoral pelas classificações de Patnaik e Kiupel, a infiltração de eosinófilos, a marcação do KIT e do Ki-67 e a presença de mutação. As variáveis foram correlacionadas utilizando os testes de qui-quadrado, teste de Fisher, teste de verossimilhança e o teste de risco relativo. Os animais idosos foram os mais acometidos, enquanto os animais sem raça definida e os das raças Boxer, Labrador e Pinscher foram aqueles com maior predisposição ao desenvolvimento tumoral. A localização e a idade estão associadas ao grau tumoral. Os tumores em cabeça, pescoço e região genital têm 10 vezes mais chance de serem classificados como de alto grau (RR=10,667; IC95% 1,909-59,615, p=0,004) e os idosos oito vezes mais chance (RR=8,00; IC95% 0,955-67,009; p=0,029). Os tumores de grau II e os de baixo grau foram os mais encontrados e as duas classificações histológicas demonstram correlação muito significativa entre si (p<0,001). A concentração do infiltrado eosinofílico não demonstrou correlação significativa com nenhuma das classificações histológicas. O padrão KIT foi dependente da localização tumoral (p=0,015), já que os tumores genitais, na cabeça e no pescoço possuíam 18 vezes mais chance de apresentarem padrão citoplasmático (RR=18,571; IC95% 1,954-176,490; p=0,003), e das classificações de Patnaik (p=0,001) e Kiupel (p<0,001), sendo que os tumores de alto grau têm 36 vezes mais chance de apresentarem padrão citoplasmático (RR=36,00, IC95% 4,35-297,948; p<0,001). A marcação do Ki-67 demonstrou dependência da localização (p=0,024). A presença de mutação no exon 11 do domínio justamembrana não demonstrou associação com nenhuma das variáveis clínicas, das classificações histológicas, da concentração de eosinófilos e do padrão KIT. A presença da mutação foi correlacionada significativamente apenas ao Ki-67 (p=0,010). Os resultados obtidos sugerem que a localização é a variável clínica mais relacionada ao prognóstico e que apenas a classificação de Kiupel associada à imuno-histoquímica são eficientes para avaliar o comportamento tumoral