Pilot study to evaluate isolation by size of circulating tumour cells in canine oral melanoma.

Liquid biopsy for circulating tumour cell (CTC) detection is generally unexplored in veterinary medicine. Dogs with highly aggressive and heterogeneous tumours, such as oral malignant melanoma (OMM), could benefit from studies involving size-based isolation methods for CTCs, as they do not depend on specific antibodies. This pilot study aimed to detect CTCs from canine OMM using Isolation by Size of Epithelial Tumor Cells (ISET), a microfiltration methodology, followed by immunocytochemistry (ICC) with Melan-A, PNL2, and S100 antibodies. Ten canine patients diagnosed by histopathology and confirmed as OMM by immunohistochemistry were enrolled, their prognostic data was assessed, and blood samples were collected for CTC analysis. Results have shown the detection of intact cells in 9/10 patients. ICC has shown 3/9 Melan-A-positive, 3/9 PNL2-positive, and 8/9 S100-positive patients, confirming the importance of opting for a multimarker assay. A significant number of negative-stained CTCs were found, suggesting their high heterogeneity in circulation. Microemboli stained with either PNL2 or S100 were found in a patient with a high isolated cell count and advanced clinical stage. Preliminary statistical analysis shows a significant difference in CTC count between patients with and without lymph node metastasis (p < .05), which may correlate with tumour metastatic potential. However, we recommend further studies with more extensive sampling to confirm this result. This pilot study is the first report of intact CTC detection in canine OMM and the first application of ISET in veterinary medicine, opening new possibilities for liquid biopsy studies in canine OMM and other tumours.

Antineoplastic effects of sodium dichloroacetate and omeprazole, alone or in combination, on canine oral mucosal melanoma cells.

Oral mucosal melanoma (OMM) is a common neoplasm in canines, although it is rare in humans. Cancer cells present alterations in energetic metabolism, and the Warburg effect states that most cancer cells undergo aerobic glycolysis. This can be reversed by certain drugs, resulting in decreased cell viability and cell death. We sought to evaluate the effects of sodium dichloroacetate (DCA) and omeprazole (OMP) alone or in combination on canine OMM and human melanoma cells. CMGD5 and SK-MEL-28 cell lines were treated with DCA and OMP alone or in combination, and cell viability was assessed using the crystal violet assay. Cell death (apoptosis and necrosis) was assessed by Annexin V and propidium iodide (PI) staining assays using flow cytometry. In addition, the oxygen consumption rate (OCR) was evaluated using a SeaHorse XF assay. Treatment with DCA or OMP alone resulted in a significant, but not dose-dependent, reduction in cell viability in both cell lines; however, the combination of DCA and OMP resulted in a significant and dose-dependent decrease in viability in both cell lines. DCA and OMP, alone or in combination, did not alter OCR at the concentrations tested in either cell line. Since the combination of DCA and OMP potentialized the inhibition of viability and increased cell death in a synergistic manner in melanoma cells, this approach may represent a new repurposing strategy to treat cancer.

Association of Systemic Inflammatory and Immune Indices With Survival in Canine Patients With Oral Melanoma, Treated With Experimental Immunotherapy Alone or Experimental Immunotherapy Plus Metronomic Chemotherapy.

Analysis of the expression of inflammatory markers before starting treatment in human patients with cancer helps to predict outcomes and prognosis; however, there have been few studies on this topic in veterinary medicine. The present study aimed to evaluate inflammatory indices before treatment with autologous antitumor vaccine alone or this vaccine plus metronomic chemotherapy (MC) to predict response and prognosis. The indices included the neutrophil-lymphocyte ratio (NRL), platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), C-reactive-protein-albumin ratio (CRP/ALB), lactate dehydrogenase level (LDH), frequency of blood lymphocyte subsets (CD4+, CD8+, Treg, and CD4/CD8 ratio) and frequency of blood myeloid-derived suppressor cells (MDSCs: monocytic [M]- MDSCs, and granulocytic [PMN]-MDSCs). Blood samples were collected from 25 dogs with oral melanoma treated with the autologous antitumor vaccine and from nine dogs that received MC plus vaccine before surgery. There were no statistically significant differences in the progression-free survival (PFS) or overall survival (OS) between the groups. In addition to the clinical stage, the CRP/ALB ratio and blood circulating Tregs in the univariate analysis showed an association with PFS and OS, and thus were selected for multivariable analysis. The CRP/ALB ratio was associated with PFS [hazard ratio (HR), 1.1; 95% confidence interval (CI), 1.0-1.1; p = 0.017] and OS [HR, 1; 95%CI, 1.0-1.1; p = 0.023]. Similarly, Treg was associated with PFS (HR, 1.6; 95% CI, 1.2-2.1; p = 0.001) and OS (HR, 1.6; 95% CI, 1.2-2.1; p = 0.001). Furthermore, canine patients with a CRP/ALB ratio above the cut-off point of 1.9 (established by receiver operating characteristic curve analysis) had worse PFS and OS, indicating the impact of the preoperative CRP/ALB ratio on the PFS and OS of dogs with oral melanoma. The CRP/ALB ratio and frequency of circulating Tregs are potential prognostic markers in dogs with oral melanoma.

Evaluation of galectins 1 and 3 expression in canine melanoma / Avaliação da expressão das galectinas 1 e 3 no melanoma canino

Canine melanoma is a frequently-occuring neoplasm in dogs and presents as malignant and highly metastatic in this context, studies that contribute to the understanding of the tumor microenvironment in melanoma include the role of galectins. Galectins are proteins of the family of animal lectins that display carbohydrate recognition domains. Galectin-1 and galectin-3 are associated with neoplastic transformation, neoplastic cell survival, angiogenesis, immune system evasion, and metastasis. The goal of this study was to establish a correlation between expression patterns of galectin-1 and galectin-3 and the different degrees of aggressiveness of canine melanoma, as well as to determine serum concentration of galectin-3 in dogs with melanoma. Galectin-1 and galectin-3 expression was analyzed by immunohistochemistry in 30 canine melanomas, six melanocytomas and nine metastatic lymph nodes from patients whose primary tumors were also processed and analyzed. Serum samples from 30 dogs were collected and galectin-3 concentration was determined by ELISA and compared to the samples of 10 healthy dogs. Canine melanoma samples expressed galectin-1 in the cytoplasm and presented a variable pattern of galectin-3 staining depending on melanoma aggressiveness. We observed a decrease in the percentage of cells with cytoplasmic galectin-3 immunolabeling simultaneous to the increased nuclear staining intensity, while there was also a decrease in the percent frequency of nuclear galectin-3 immunolabeled cells according to progression of melanoma, comparing the least to the most aggressive cases. Dogs with melanoma had increased serum levels of galectin-3 when compared to healthy animals, suggesting its potential biomarker of patients with melanoma.(AU)

O melanoma canino é uma neoplasia frequente em cães que apresenta um potencial maligno e metastático. Neste contexto, investigar o microambiente tumoral é fundamental para compreender os mecanismos intercelulares e intracelulares envolvidos no desenvolvimento e progressão da doença. Neste estudo, destacamos as galectinas, proteínas da família das lectinas animais que exibem domínios de reconhecimento à carboidratos; a galectina-1 e a galectina-3 estão associadas a transformação neoplásica, sobrevivência de células neoplásicas, angiogênese, evasão do sistema immune e desenvolvimento de metástases. O objetivo deste estudo foi determinar os padrões de expressão de galectina-1 e galectina-3 em diferentes graus de agressividade do melanoma canino, bem como dosar a concentração sérica de galectina-3 em cães com melanoma e comparar com cães saudáveis. A expressão de galectina-1 e galectina-3 foi analisada em 30 melanomas caninos, seis melanocitomas e nove linfonodos metastáticos. A galectina-3 sérica foi mensurada em 30 cães com melanoma e comparada a 10 cães saudáveis. No melanoma canino a expressão de galectina-1 foi citoplasmática e a expressão de galectina-3 foi variável de acordo com o grau de agressividade. Notou-se uma redução na porcentagem de células com imunomarcação de galectina-3 citoplasmática e um aumento simultâneo da intensidade de imunomarcação nuclear, enquanto houve também uma diminuição na frequência percentual de células com imunomarcação nuclear de acordo com a progressão do melanoma comparando-se os casos menos com os mais agressivos. Cães com melanoma apresentaram níveis séricos aumentados de galectina-3 quando comparados a animais saudáveis, mostrando seu uso potencial como biomarcador em pacientes com melanoma.(AU)

Gene expression of the immunoinflammatory and immunological status of obese dogs before and after weight loss.

Obesity is characterized by a low degree of chronic inflammation state that, along with metabolic modifications, promotes important changes in the animal's organism. Adipose tissue actively participates in inflammation and immunity, and several defense cells of the organism may, therefore, be involved in the diversity found between obese and ideal weight individuals. Studies regarding this subject have shown immune cell changes in humans and rats, however, the literature is scarce in relation to dogs. Thus, the present study aimed to evaluate the gene expression profile of immunoinflammatory response and the lymphoproliferation of obese dogs before and after weight loss. Eight female dogs, neutered, of different breeds, aged between 1 and 8 years (4.74±3.19), obese, with body condition score (BCS) of 9 out of a 9-point scale and body composition determined by the deuterium isotope dilution method were included. The obese dogs were enrolled in a weight loss program and after losing 20% of their initial weight became a second experimental group. A third experimental group consisted of eight female dogs, neutered, aged between 1 and 8 years (3.11±0.78) and with ideal BCS (5 out of a 9-point scale). Gene expression of immunoinflammatory cytokines (resistin, leptin, adiponectin, TNF-α, IL-6, IL-8, and IL-10) was assessed by qRT-PCR and immunity was assessed by lymphoproliferative response using the flow cytometry technique. The data that presented normal distribution was evaluated by analysis of variance by the PROC MIXED of the SAS and when differences were detected, these were compared by the Tukey test. Regarding the gene expression data, the procedure PROC GLIMMIX was adopted and the methodology of generalized linear model was used, in which the Gama distribution proved to be adequate. Values of p<0.05 were considered significant. The mean weight loss period of the animals included in the study was 194.25 ± 28.31 days and the mean weekly weight loss rate was 1.02 ± 0.82%. The average fat mass, both in percentage (P<0.001) and in kilograms (P = 0.012), was higher in the obese group (40.88%; 8.91kg), returning to normal and without difference between the control group (19.16%; 3.01kg) and after weight loss (22.10%; 4.11kg). The weight loss program resulted in an increase in percentage of lean body mass (P = 0.001), 55.50% in obese animals vs 77.90% in obese dogs after weight loss, the latter with no difference when compared to the control group (80.84%). The obese group presented increased gene expression of resistin and IL-8 in relation to the weight loss group (P = 0.002). In adiponectin, the obese group presented increased mRNA gene expression when compared to the weight loss group (P = 0.003). The evaluation of lymphocyte proliferation showed differences between the group of obese animals before and after weight loss (P = 0.004). Weight loss resulted in an increase in the lymphoproliferation rate (18.48%) compared to obese dogs at the beginning of the study (10.71%). These results indicate that weight loss modulates the immunoinflammatory response of obese dogs and may present important benefits to health and longevity of dogs.

Linfocitose extrema associada à leucemia linfoblástica aguda (LLA) de células T em um cão jovem: relato de caso / Extreme lymphocytosis associated with acute T-cell lymphoblastic leukemia (ALL) in a young dog: case report

A leucemia linfoblástica aguda (LLA) é uma enfermidade de origem linfóide e consiste na proliferação de células neoplásicas na medula óssea. O objetivo desse trabalho é relatar o caso de um cão macho, sem raça definida, de apenas um ano de idade, atendido no Hospital Universitário de Medicina Veterinária Prof. Firmino Mársico Filho (HUVET) da Universidade Federal Fluminense (UFF) com queixa principal de inapetência e diarreia há três dias e que foi diagnosticado com essa neoplasia por meio da sintomatologia clínica, resultados do hemograma e do mielograma. O paciente apresentava valores exacerbados de linfócitos (553.094 células/µL), além de anemia, trombocitopenia, hipoalbuminemia e elevação da atividade das enzimas fosfatase alcalina e ALT. Foram observadas manchas de Gümprecht, linfócitos atípicos apresentando anisocitose, anisocariose, intensa basofilia citoplasmática e monócitos ativados. O mielograma apresentou também um aumento de linfócitos e contagem de linfoblastos superior a 30% na medula, confirmando o diagnóstico de leucemia linfoblástica aguda. Ademais, posteriormente, foi realizado exame de Reação em Cadeia de Polimerase (PCR) para rearranjos de receptores de antígenos e foi detectado clonalidade para linfócitos T. O animal foi submetido à quimioterapia (protocolo com ciclofosfamida, vincristina e prednisona) mas não resistiu à gravidade do quadro, vindo a óbito após a primeira sessão, pouco tempo após o diagnóstico.

Acute lymphoblastic leukemia (LLA) is a disease with a lymphoid origin and consists of the proliferation of neoplastic cells in the bone marrow. The aim of this study was to report the case of only one year old mixed breed male dog, attended at the University Hospital of Veterinary Medicine Prof. Firmino Mársico Filho (HUVET) from Universidade Federal Fluminense (UFF), with major complaint of inappetence and diarrhea three days ago and which was diagnosed with this neoplasm through clinical symptoms, complete blood count and myelogram results. The patient had increased values of lymphocytes (553,094 cells/µL), in addition to anemia, thrombocytopenia, hypoalbuminemia and elevated alkaline phosphatase and ALT activities. Gümprecht shadows, atypical lymphocytes presenting anisocytosis, anisocariosis, and severe cytoplasmic basophilia and activated monocytes were observed. Myelogram also showed an increase in lymphocytes and a lymphoblastic count greater than 30% in the marrow, confirming the diagnosis of LLA. In addition, polymerase chain reaction (PCR) for antigen receptor rearrangements was performed and clonality for T lymphocytes was detected. The animal underwent chemotherapy (protocol with cyclophosphamide, vincristine and prednisone), but did not withstand the severity of the disease, coming to death after the first session, shorly after diagnosis.

Linfocitose extrema associada à leucemia linfoblástica aguda (LLA) de células T em um cão jovem: relato de caso / Extreme lymphocytosis associated with acute T-cell lymphoblastic leukemia(ALL) in a young dog: case report

A leucemia linfoblástica aguda (LLA) é uma enfermidade de origem linfóide e consiste na proliferação de células neoplásicas na medula óssea. O objetivo desse trabalho é relatar o caso de um cão macho, sem raça definida, de apenas um ano de idade, atendido no Hospital Universitário de Medicina Veterinária Prof. Firmino Mársico Filho (HUVET) da Universidade Federal Fluminense (UFF) com queixa principal de inapetência e diarreia há três dias e que foi diagnosticado com essa neoplasia por meio da sintomatologia clínica, resultados do hemograma e do mielograma. O paciente apresentava valores exacerbados de linfócitos (553.094 células/µL), além de anemia, trombocitopenia, hipoalbuminemia e elevação da atividade das enzimas fosfatase alcalina e ALT. Foram observadas manchas de Gümprecht, linfócitos atípicos apresentando anisocitose, anisocariose, intensa basofilia citoplasmática e monócitos ativados. O mielograma apresentou também um aumento de linfócitos e contagem de linfoblastos superior a 30% na medula, confirmando o diagnóstico de leucemia linfoblástica aguda. Ademais, posteriormente, foi realizado exame de Reação em Cadeia de Polimerase (PCR) para rearranjos de receptores de antígenos e foi detectado clonalidade para linfócitos T. O animal foi submetido à quimioterapia (protocolo com ciclofosfamida, vincristina e prednisona), mas não resistiu à gravidade do quadro, vindo a óbito após a primeira sessão, pouco tempo após o diagnóstico.

Acute lymphoblastic leukemia (LLA) is a disease with a lymphoid origin and consists of the proliferation of neoplastic cells in the bone marrow. The aim of this study was to report the case of only one year old mixed breed male dog, attended at the University Hospital of Veterinary Medicine Prof. Firmino Mársico Filho (HUVET) from Universidade Federal Fluminense (UFF), with major complaint of inappetence and diarrhea three days ago and which was diagnosed with this neoplasm through clinical symptoms, complete blood count and myelogram results. The patient had increased values of lymphocytes (553,094 cells/μL), in addition to anemia, thrombocytopenia, hypoalbuminemia and elevated alkaline phosphatase and ALT activities. Gümprecht shadows, atypical lymphocytes presenting anisocytosis, anisocariosis, and severe cytoplasmic basophilia and activated monocytes were observed. Myelogram also showed an increase in lymphocytes and a lymphoblastic count greater than 30% in the marrow, confirming the diagnosis of LLA. In addition, polymerase chain reaction (PCR) for antigen receptor rearrangements was performed and clonality for T lymphocytes was detected. The animal underwent chemotherapy (protocol with cyclophosphamide, vincristine and prednisone), but did not withstand the severity of the disease, coming to death after the first session, shortly after diagnosis.