Epidemiology of canine cutaneous round cell tumours on the canary archipelago in Spain.

In this study we undertook a comprehensive analysis of a Pet Tumour Registry of the Canary Archipelago (PTR-CA) in Spain to investigate the epidemiology of canine cutaneous round cell tumours. From a database of 2526 tumours collected from 2003 to 2020, we conducted a longitudinal analysis of the main trends in diagnosis, age, multiplicity and anatomical distribution as well as a case-control study comparing these cases with the contemporaneous canine population of the Canary Archipelago to analyse breed distribution. In line with former studies, we found histiocytomas mostly affect young dogs (2, IQR 1-5) and mast cell tumours affect middle-to-old dogs (8, IQR 6-10) with grade 1 affecting at younger ages (6.5, IQR 6-8) than both grade 2 (8, IQR 6-10 years) and grade 3 (9, IQR 7-11). Histiocytomas and plasmacytomas showed a similar anatomical distribution appearing mainly on the face, head and neck regions while mast cell tumours occur mainly on limbs and trunk. Higher risk for mast cell tumours and histiocytomas were found for Bulldog-related breeds such as Boxer (ORMCT = 23.61, CI95%: 19.12-29.15, ORHCT = 10.17, CI95%: 6.60-15.67), Boston Terrier (ORMCT 19.47, CI95%: 7.73-49.05, ORHCT 32.61, CI95%: 11.81-90.07) and Pug (ORMCT 8.10, CI95%: 5.92-11.07, ORHCT 7.87, CI95%: 4.66-13.28) while Chihuahua dogs showed significantly less risk (ORMCT 0.18, CI95%: 0.09-0.33, ORHCT 0.41, CI95%: 0.21-0.78). Notably, the Canarian Mastiff, a local breed, had a low risk of suffering from a mast cell tumour which raises the question of whether this relates to a genetic peculiarity of this breed or some husbandry and environmental factor.

Budd-Chiari-like pathology in dolphins.

Nearly two decades ago, pathologic examination results suggested that acoustic factors, such as mid-frequency active naval military sonar (MFAS) could be the cause of acute decompression-like sickness in stranded beaked whales. Acute systemic gas embolism in these whales was reported together with enigmatic cystic liver lesions (CLL), characterized by intrahepatic encapsulated gas-filled cysts, tentatively interpreted as "gas-bubble" lesions in various other cetacean species. Here we provide a pathologic reinterpretation of CLL in odontocetes. Among 1,200 cetaceans necropsied, CLL were only observed in four striped dolphins (Stenella coeruleoalba), with a low prevalence (2%, N = 179). Together, our data strongly suggest that CLL are the result of the combination of a pre-existing or concomitant hepatic vascular disorder superimposed and exacerbated by gas bubbles, and clearly differ from acute systemic gas embolism in stranded beaked whales that is linked to MFAS. Budd-Chiari-like syndrome in dolphins is hypothesized based on the present pathologic findings. Nonetheless, further researched is warranted to determine precise etiopathogenesis(es) and contributing factors for CLL in cetaceans.

Epidemiology of canine mammary tumours on the Canary Archipelago in Spain.

BACKGROUND: Mammary gland tumours are the most frequently diagnosed tumours in the female dogs but just a few studies have analysed their epidemiology. Therefore, we set out to describe the epidemiology of canine mammary cancer in the Canary Archipelago, Spain. We analysed a pathology tumour registry (PTR) and identified 7362 samples obtained from 5240 female dogs resident on the Canary Archipelago during an 18-year period (2003-2020). Using a case-control study design, we compared mammary tumour affected dogs with the Canarian canine population registry in order to elucidate the breed associations for these tumours. RESULTS: The frequency of a diagnosis of mammary tumours relative to all tumour diagnoses in female dogs decreased during the study period from 62.7% to 48.9%. Contemporaneously, the proportion of dogs diagnosed with mammary tumours who were also neutered increased from 13.6% to 26.9%. There was a negative correlation (R = -0.84) between these changes. Additional findings were that: the proportion of female dogs diagnosed with multiple tumours increased by 23.5% and that the proportion of malignant tumours 89.2% diagnosed has remained stable through the period. Benign mammary tumours were diagnosed at younger ages (9.2 years old) than carcinomas (9.7 years old) and sarcomas (10.4 years old). Epithelial mammary tumours were diagnosed at younger ages in entire female dogs. Samoyed, Schnauzer, Poodle, German Pinscher and Cocker Spaniel were the breeds with the highest odds-ratios (OR) in comparison with the reference (crossbreeds) while Miniature Pinscher, American Staffordshire Terrier, English Pointer as well as some local breeds such as the Canary Warren Hound and the Majorero had the lowest ORs. CONCLUSIONS: This study provides a description of the changing epidemiology of canine mammary cancer in the Canary Archipelago over the last two decades. We found high rates of CMT with a significant predominance of malignant tumours. Exact risk factors are uncertain, but a combination of environmental, regional socioeconomic affecting human and their pets, and animal management factors are likely to play a part. Specifically, neutering was negatively associated with the proportion of epithelial mammary gland tumours and breeds native to the region were at lower risk of mammary tumours. A deeper analysis of all these factors will facilitate a deeper understanding of the epidemiology of mammary gland tumours in both the canine and the human population.

Methodology and Neuromarkers for Cetaceans' Brains.

Cetacean brain sampling may be an arduous task due to the difficulty of collecting and histologically preparing such rare and large specimens. Thus, one of the main challenges of working with cetaceans' brains is to establish a valid methodology for an optimal manipulation and fixation of the brain tissue, which allows the samples to be viable for neuroanatomical and neuropathological studies. With this in view, we validated a methodology in order to preserve the quality of such large brains (neuroanatomy/neuropathology) and at the same time to obtain fresh brain samples for toxicological, virological, and microbiological analysis (neuropathology). A fixation protocol adapted to brains, of equal or even three times the size of human brains, was studied and tested. Finally, we investigated the usefulness of a panel of 20 antibodies (neuromarkers) associated with the normal structure and function of the brain, pathogens, age-related, and/or functional variations. The sampling protocol and some of the 20 neuromarkers have been thought to explore neurodegenerative diseases in these long-lived animals. To conclude, many of the typical measures used to evaluate neuropathological changes do not tell us if meaningful cellular changes have occurred. Having a wide panel of antibodies and histochemical techniques available allows for delving into the specific behavior of the neuronal population of the brain nuclei and to get a "fingerprint" of their real status.

Expression of cell cycle regulators, 14-3-3σ and p53 proteins, and vimentin in canine transitional cell carcinoma of the urinary bladder.

OBJECTIVES: The study of the expression of 14-3-3σ, p53, and vimentin proteins in canine transitional cell carcinoma (TCC) evaluating differences with normal bladder tissues, and the association with clinicopathological variables. METHODS: We analyze by immunohistochemistry in 19 canine TCCs the expression of 14-3-3σ, p53, and vimentin using monoclonal antibodys. A semiquantitative scoring method was employed and statistical analysis was performed to display relationships between variables. RESULTS: In contrast to normal urinary bladder epithelium, which showed high levels of 14-3-3σ, its expression was decreased in 53% of the studied tumors (P = 0.0344). The 14-3-3σ protein was expressed by neoplastic emboli and by highly infiltrative neoplastic cells. The p53 protein was expressed in 26% of TCCs, but no significant association between 14-3-3σ and p53 was detected. Neoplastic epithelial cells displayed vimentin immunoreactivity in 21% of TCCs, and a positive correlation with mitotic index was observed (P = 0.042). Coexpression of vimentin and 14-3-3σ by highly infiltrative neoplastic cells was also observed. CONCLUSIONS: 14-3-3σ is deregulated in canine TCCs and its expression by highly infiltrative tumor cells may be related to the acquisition of aggressive behavior. Furthermore, this article reinforce the role of canine TCC as relevant model of human urothelial carcinoma and we suggest 14-3-3σ as a potential therapeutic target. Further studies are necessary to clarify the role of 14-3-3σ in canine TCC.

Expression of 14-3-3 σ protein in normal and neoplastic canine mammary gland.

14-3-3 σ protein is a negative cell cycle regulator, with both reduced and elevated levels associated with cancer in humans. This study assessed the expression of this protein in canine mammary tissues using immunohistochemistry and Western blotting. 14-3-3 σ was detected in 97% of the mammary tissue samples examined and was found in both myoepithelial (MECs) and epithelial (ECs) cells. Expression levels were elevated and reduced in neoplastic ECs and MECs, respectively (P<0.001). Intense expression of 14-3-3 σ was detected in neoplastic ECs infiltrating blood vessels and lymph nodes and suggests a possible role for this protein in the malignant transformation of mammary neoplasms. Moreover, double immunostaining for 14-3-3 σ and the MEC-specific marker p63, confirmed that 14-3-3 σ is a highly sensitive marker of MECs since all p63-positive cells were also positive for 14-3-3 σ. However, this protein is not exclusive to MECs as ECs also labelled positively.

Immunohistochemical localisation of 14-3-3 sigma protein in normal canine tissues.

The 14-3-3 sigma protein, also called stratifin, belongs to the highly conserved family of 14-3-3 acid proteins, which are involved in the modulation of diverse signal transduction pathways. Loss of 14-3-3 sigma expression has been observed in several types of human cancers, suggesting that it may have a role as a tumour suppressor gene. The 14-3-3 sigma protein has been localised in normal human tissues exclusively in various epithelial cell types. The aim of the study was to investigate the expression and the distribution pattern of 14-3-3 sigma by immunohistochemical analysis in normal canine tissues. Immunohistochemical expression of 14-3-3 sigma was demonstrated in several normal canine tissues with some minor differences of distribution pattern compared with human tissues. It appears that 14-3-3 sigma is a very specific epithelial cell marker in normal canine tissues.