Inhibiting aberrantly upregulated microRNAs (miR/miRNAs) has emerged as a novel focus for therapeutic intervention in human melanoma. Thus, identifying upregulated miRNAs is essential for identifying additional melanoma-associated therapeutic targets. In the present study, microarray-based miRNA profiling of canine malignant melanoma (CMM) tissue obtained from the oral cavity was performed and differential expression was confirmed by a reverse transcription-quantitative polymerase chain reaction (RT-qPCR). An analysis of the microarray data revealed 17 dysregulated miRNAs; 5 were upregulated and 12 were downregulated. RT-qPCR analysis was performed for 2 upregulated (miR-204 and miR-383), 3 downregulated (miR-122, miR-143 and miR-205) and 6 additional oncogenic miRNAs (oncomiRs; miR-16, miR-21, miR-29b, miR-92a, miR-125b and miR-222). The expression levels of seven of the miRNAs, miR-16, miR-21, miR-29b, miR-122, miR-125b, miR-204 and miR-383 were significantly upregulated; however, the expression of miR-205 was downregulated in CMM tissues compared with normal oral tissues. The microarray and RT-qPCR analyses validated the upregulation of two potential oncomiRs miR-204 and miR-383. The present study additionally constructed a protein interaction network and a miRNA-target regulatory interaction network using STRING and Cytoscape. In the proposed network, cyclin dependent kinase 2 was a target for miR-383, sirtuin 1 and tumor protein p53 were targets for miR-204 and ATR serine/threonine kinase was a target for both. It was concluded that miR-383 and miR-204 were potential oncomiRs that may be involved in regulating melanoma development by evading DNA repair and apoptosis.

A 4-year-old male Japanese Shiba Inu presented with recurrent chylothorax. The thoracic duct was successfully imaged using computed tomography after the injection of an iodine contrast agent into the subcutaneous tissue surrounding the anus. The thoracic duct was successfully ligated and pericardectomy performed via an open thoracotomy. Pleural effusion improved but relapsed a week after the surgery. A second lymphography revealed a collateral thoracic duct that was not detected during the first lymphography. The collateral duct was ligated and chylothorax was resolved after the second surgery. The lymphography applied in this study was minimally-invasive and easily provided images of the thoracic duct in a dog with chylothorax.

Canine hepatocellular carcinoma (HCC) is the most common primary hepatic tumour in dogs. MicroRNA (miRNA) dysregulation has been reported in human HCC and shown to have diagnostic and prognostic value; however, there are no data on miRNA expression in canine HCC. The aim of the present study was to investigate differentially expressed miRNAs in canine HCC. Analysis of miRNA expression in canine HCC tissues and cell lines by quantitative reverse transcription PCR showed that miR-1, miR-122, let-7a, and let-7g were downregulated, whereas miR-10b and miR-21 were upregulated in canine HCC. MET is one of the target genes of miR-1. MET was upregulated in canine HCC at the gene and protein levels, and a significant correlation between the concomitant downregulation of miR-1 and upregulation of MET was observed. Fast/intermediate-proliferating canine HCC cell lines had higher MET gene and protein expression levels than the slow-proliferating cell line. These findings suggest that miRNAs are differentially expressed in canine HCC, and that the miR-1/MET pathway may be associated with canine HCC cell proliferation.

Many human epidemiologic studies have reported associations between plasma homocysteine (Hcy) concentrations and cardiovascular disease, Alzheimer's disease, and osteoporosis. However, few studies have examined the relationship between Hcy and disease in dogs. In this study, we investigated the relationship between canine plasma Hcy concentrations and sex, age, breed, size; spay/neuter status, and disease. Plasma Hcy concentrations were related to sex and age, but the correlations were very weak. ShibaInu dogs and Labrador Retrievers had a higher risk of hyperhomocysteinemia than other breeds. We compared the plasma Hcy concentrations of healthy control dogs with those of dogs with heart, inflammatory, bone and joint, nervous system, neoplastic, skin, and kidney diseases. The mean plasma Hcy concentrations of dogs with cardiovascular, neoplasia, skin, and kidney diseases were significantly different from those of controls. However, multivariate logistic regression (parameters: Hcy concentration, age, sex, and spay/neuter status) revealed a significant relationship between only skin disease and plasma Hcy concentration. The odds ratio (per 1 μmol/l increase of Hcy) was 1.077 (95% confidence interval 1.00-1.158, p<0.05). Plasma Hcy concentrations significantly differ among dog breeds, and there is a relationship between high plasma Hcy concentration and skin disease.

The pancreas is believed to be vulnerable to hypoperfusion. In dogs with acute pancreatitis, pancreatic ischemia due to heart failure can worsen the condition. However, changes in pancreatic blood flow associated with decreased cardiac function have not been previously studied in dogs. Therefore, we aimed to identify and compare changes in pancreatic versus renal blood flow as a result of cardiac dysfunction. Seven dogs were subjected to rapid ventricular pacing to create heart failure models. Noninvasive blood pressure measurement, echocardiography, contrast-enhanced ultrasonography for pancreatic blood flow measurement, and para-aminohippuric acid clearance for renal blood flow measurement were performed before starting and at 2 and 4 weeks after starting the pacing. Left ventricular cardiac output and mean blood pressure decreased at 2 and 4 weeks after starting the pacing, and pancreatic blood flow decreased at 2 and 4 weeks after starting the pacing. However, renal blood flow did not change at 2 weeks but decreased 4 weeks after starting the pacing. Overall, this study demonstrated that reduced pancreatic blood flow due to cardiac dysfunction occurs, similar to renal blood flow. This suggests that decreased pancreatic blood flow is not unusual and may frequently occur in dogs with heart failure. The results of this study support the speculation that heart failure can exacerbate acute pancreatitis. Additionally, this study provides useful basic information for designing further studies to study this association.