PD-L1, PD-1, and CTLA-4 mRNA In Situ Expression by Canine Oral Melanoma Cells and Immune Cells of the Tumour Microenvironment.

Canine oral melanoma (OM) exhibits poor prognosis and limited treatment options. The success of immune checkpoint inhibitors (ICIs) in human melanoma has driven interest in similar therapeutic approaches in the dog, although the immunosuppressive mechanisms adopted by canine OM remain unclear. This study aimed to evaluate the expression of the immune checkpoints PD-1/PD-L1 and CTLA-4 by RNAscope in situ hybridization (ISH) in canine OM, to investigate their expression pattern and explore their potential role in melanoma progression.

Flow Cytometry for the Detection and Quantification of Mast Cells in Lymph Nodes: A Prospective Study in 64 Dogs With Mast Cell Tumour.

Nodal metastasis is a negative prognostic factor in dogs with mast cell tumours (MCTs), thus early detection enables more informed decision-making and provides valuable prognostic information. The aim of this study is to assess the concordance between histopathologic findings of LNs and cytology and flow cytometry (FC), respectively, and to evaluate the ability of FC to differentiate between metastatic (HN2-HN3) and non-metastatic (HN0-HN1) LNs. Overall, 117 LNs from 64 dogs with first occurring MCTs were submitted for cytology, histology and FC.

Histologic, Phenotypic, and Molecular Characterization of Feline Hodgkin-Like Lymphoma With Classical Reed-Sternberg Cells.

Hodgkin-like lymphoma (HLL) is a rare neoplasm in cats that shares characteristics with the human disease. The hallmark of HLL is the presence of Reed-Sternberg (RS) cells expressing CD30 and CD20. This study aimed to elucidate the clinicopathologic features, immunophenotype and clonality patterns of feline HLL.

The diagnostic relevance of mesenteric lymph node biopsy in small intestinal lymphoma in cats.

Background: Regional lymph nodes are frequently sampled in cats with suspected intestinal lymphoma; however, their diagnostic value has not been explored.

Objectives: To investigate whether histologic and immunohistochemical analysis of mesenteric lymph nodes correlates with the diagnosis of intestinal lymphoma in cats.

Animals: One hundred 2 client-owned cats diagnosed with intestinal lymphoma.

Granulocytic neoplasm suggestive of primary myeloid sarcoma in 3 dogs.

Myeloid sarcoma (MS) is a solid tumor of granulocytic origin with extramedullary localization. This tumor is rare in humans and animals. The diagnostic approach is heterogeneous, and the definitive diagnosis may be difficult to achieve.

Hypoxia-associated markers in the prognosis of oral canine melanoma.

Canine oral malignant melanoma (COMM) is the most common neoplasm in the oral cavity characterized by local invasiveness and high metastatic potential. Hypoxia represents a crucial feature of the solid tumor microenvironment promoting cancer progression and drug resistance. Hypoxia-inducible factor-1α (HIF-1α) and its downstream effectors, vascular endothelial growth factor A (VEGF-A), glucose transporter isoform 1 (GLUT1), C-X-C chemokine receptor type 4 (CXCR4), and carbonic anhydrase IX (CAIX), are the main regulators of the adaptive response to low oxygen availability.

A chimeric human/dog-DNA vaccine against CSPG4 induces immunity with therapeutic potential in comparative preclinical models of osteosarcoma.

The high mortality rate of osteosarcoma (OSA) patients highlights the requirement of alternative strategies. The young age of patients, as well as the rarity and aggressiveness of the disease, limits opportunities for the robust testing of novel therapies, suggesting the need for valuable preclinical systems. Having previously shown the overexpression of the chondroitin sulfate proteoglycan (CSPG)4 in OSA, herein the functional consequences of its downmodulation in human OSA cells were evaluated in vitro, with a significant impairment of cell proliferation, migration, and osteosphere generation.

Bridging clinic and wildlife care with AI-powered pan-species computational pathology.

Cancers occur across species. Understanding what is consistent and varies across species can provide new insights into cancer initiation and evolution, with significant implications for animal welfare and wildlife conservation. We build a pan-species cancer digital pathology atlas (panspecies.

Ex vivo evaluation of a technique for equine jejunocecal anastomosis using radiofrequency thermofusion and a Cushing oversew.

Objective: To describe a technique for a side-to-side jejunocecal anastomosis in horses using radiofrequency thermofusion (TF) of the intestines supported by a Cushing oversew and to compare this anastomosis to handsewn and stapled techniques.

Study Design: Ex vivo study.

Sample Population: Intestinal tracts from 24 slaughtered horses.

Sentinel lymph node mapping with computed tomography lymphography for mast cell tumours and a comparison between regional and sentinel lymph node histological status: Sixty-two cases.

It is known that the regional lymph node (RLN) may not correspond to the sentinel lymph node (SLN) (the first lymph node draining the tumour), and many diagnostic techniques have recently been aimed at its detection. Although lymphoscintigraphy is the gold standard in both human and veterinary medicine for SLN mapping, it is relatively unavailable in veterinary medicine due to costs and difficult management of the radiotracer. This prospective study evaluated, as a first aim, the feasibility and sensitivity of the computed tomography lymphography (CTL) in detecting the SLN in 62 mast cell tumours (MCTs).

Development of Monoclonal Antibodies Targeting Canine PD-L1 and PD-1 and Their Clinical Relevance in Canine Apocrine Gland Anal Sac Adenocarcinoma.

Canine apocrine gland anal sac adenocarcinoma (AGASACA) is an aggressive canine tumor originating from the anal sac glands. Surgical resection, with or without adjuvant chemotherapy, represents the standard of care for this tumor, but the outcome is generally poor, particularly for tumors diagnosed at an advanced stage. For this reason, novel treatment options are warranted, and a few recent reports have suggested the activation of the immune checkpoint axis in canine AGASACA.

Investigating a Prognostic Factor for Canine Hepatocellular Carcinoma: Analysis of Different Histological Grading Systems and the Role of PIVKA-II.

Background: Hepatocellular carcinoma (HCC) in dogs is uncommon and often associated with a good prognosis, although some cases prove to be aggressive. In human oncology HCC is often very aggressive and diagnostic methods and prognostic factors are widely used to predict its biological behaviour. These include the expression of PIVKA-II.

Feline ovarian tissue vitrification: The effect of fragment size and base medium on follicular viability and morphology.

To achieve optimal vitrification, tissue structure and fragment size represent a challenge for obtaining sufficient cooling velocity. Theoretically, thin ovarian tissue fragments lead to higher surface contact, hence higher solute penetration. Another critical factor is the concentration of cryoprotectants (CPA): CPA toxicity may occur with high concentrations, and as such, this may induce local apoptosis.

The mitotic regulator polo-like kinase 1 as a potential therapeutic target for c-Myc-overexpressing canine osteosarcomas.

Osteosarcoma is the most common primary malignant bone tumour in dogs, characterized by a locally aggressive and highly metastatic behaviour. Despite the current standards of care, most dogs succumb to the disease, indicating the need for novel treatment strategies. Polo-like kinase 1 (PLK1) is dysregulated in a variety of human cancer types, including osteosarcoma, and induces c-Myc accumulation.

Reproducibility and Feasibility of Classification and National Guidelines for Histological Diagnosis of Canine Mammary Gland Tumours: A Multi-Institutional Ring Study.

Histological diagnosis of Canine Mammary Tumours (CMTs) provides the basis for proper treatment and follow-up. Nowadays, its accuracy is poorly understood and variable interpretation of histological criteria leads to a lack of standardisation and impossibility to compare studies. This study aimed to quantify the reproducibility of histological diagnosis and grading in CMTs.

Canine and feline in situ mammary carcinoma: A comparative review.

Carcinoma in situ of the breast is a well-known entity in humans. In veterinary medicine, particularly in canine and feline mammary literature, there is no agreement whether the term in situ should be used to indicate a specific carcinoma histotype or the noninvasive status of a carcinoma of any histotype. Moreover, in the most recent histologic classification of mammary tumors published by the Davis-Thompson Foundation, it is suggested to abandon the term carcinoma in situ given the lack of standardized criteria defining this entity, replacing it with epitheliosis or ductal/lobular hyperplasia with severe atypia.

Antigen mimicry as an effective strategy to induce CSPG4-targeted immunity in dogs with oral melanoma: a veterinary trial.

Background: Melanoma is the most lethal form of skin cancer in humans. Conventional therapies have limited efficacy, and overall response is still unsatisfactory considering that immune checkpoint inhibitors induce lasting clinical responses only in a low percentage of patients. This has prompted us to develop a vaccination strategy employing the tumor antigen chondroitin sulfate proteoglycan (CSPG)4 as a target.

In Vivo Evaluation of a Pectin-Honey Hydrogel Coating on Polypropylene Mesh in a Rat Model of Acute Hernia.

Investigations about ventral hernia repair are focused on improving the quality, resistance, and biocompatibility of mesh. This study compared plain polypropylene mesh with a pectin-honey hydrogel-coated polypropylene mesh in an acute hernia model in rats. Forty Wistar rats, randomly assigned to two groups, were submitted to laparotomy, and a 1 cm × 2 cm fascial defect was created, centered on the midline.

Prognostic impact of bone invasion in canine oral malignant melanoma treated by surgery and anti-CSPG4 vaccination: A retrospective study on 68 cases (2010-2020).

Prognosis of canine oral malignant melanoma encompasses clinical, histological and immunohistochemical parameters. The aim of this study was to evaluate the prognostic impact of bone invasion in oral canine melanoma. Sixty-eight dogs bearing oral melanoma staged II and III that underwent surgery and anti-CSPG4 electrovaccination, with available histological data and a minimum follow up of minimum 1 year, were retrospectively selected.

Prognostic Value of Ki67 and Other Clinical and Histopathological Factors in Canine Apocrine Gland Anal Sac Adenocarcinoma.

Apocrine gland anal sac adenocarcinoma (AGASACA) is locally aggressive and highly metastatic to regional lymph nodes. The aim of this study was to evaluate the prognostic significance of Ki67 in surgically excised AGASACA. Prognostic impact of size, regional lymph nodes metastasis, hypercalcemia, histologic pattern, mitotic count, necrosis, inflammatory and lympho-vascular invasion, anisokaryosis and anisocytosis was also evaluated.

Genomic and Transcriptomic Characterization of Canine Osteosarcoma Cell Lines: A Valuable Resource in Translational Medicine.

Osteosarcoma (OSA) represents the most common primary bone tumor in dogs and is characterized by a highly aggressive behavior. Cell lines represent one of the most suitable and reproducible pre-clinical models, and therefore the knowledge of their molecular landscape is mandatory to investigate oncogenic mechanisms and drug response. The present study aims at determining variants, putative driver genes, and gene expression aberrations by integrating whole-exome and RNA sequencing.

Benign or Low-Grade Malignant Masses Occupying the Pelvic Canal Space in 11 Dogs.

Dogs with benign intra-pelvic rectal or vaginal masses show symptoms indicating compression on the adjacent organs. Clinical signs usually develop late when the lesion is large enough to interfere functionally. The dogs were referred for severe fecal and/or urinary tenesmus.

Histopathological Classification of Canine Cutaneous Round Cell Tumors Using Deep Learning: A Multi-Center Study.

Canine cutaneous round cell tumors (RCT) represent one of the routine diagnostic challenges for veterinary pathologists. Computer-aided approaches are developed to overcome these restrictions and to increase accuracy and consistency of diagnosis. These systems are also of high benefit reducing errors when a large number of cases are screened daily.

Difference in outcome between curative intent vs marginal excision as a first treatment in dogs with oral malignant melanoma and the impact of adjuvant CSPG4-DNA electrovaccination: A retrospective study on 155 cases.

Canine oral malignant melanoma is locally invasive and highly metastatic. At present, the best option for local control is en bloc excision followed by radiation if excision margins are incomplete. Adjuvantly, the role of chemotherapy is dubious while immunotherapy appears encouraging.