Evaluation of Serum Acute Phase Protein Concentrations in Dogs with Circumanal Gland Tumours.

The aim of this study was to determine the serum concentrations of acute phase proteins (APPs), including C-reactive protein (CRP), serum amyloid A (SAA) and haptoglobin (Hp) in dogs with circumanal gland tumours. Investigations were conducted on 39 male dogs of mixed breed. The animals were divided into four groups depending on the degree of tumour malignancy and type of hormones that were dominant in the bloodstream. All measurements of serum APPs were conducted by the use of commercial diagnostic kits. In dogs with benign tumours, the concentrations of each APP decreased during therapy, while in dogs with malignant tumours, despite anti-tumour therapy, concentrations of APPs in serum increased markedly. The results of this study suggest that changes in serum concentrations of CRP, SAA and Hp during anti-hormone therapy may be a reliable marker for differentiating tumour grade and degree of malignancy. Including APPs in routine diagnostics may assist with formulating a prognosis for the outcome of the disease, before implementing anti-tumour therapy. Moreover, monitoring the effectiveness of therapy may be possible based on the determination of serum APP concentrations.

Evaluation of T regulatory lymphocytes and serum concentration of selected cytokines in dogs with perianal tumors.

The purpose of this study was to determine concentrations of IL-2, IL-10, TGF-ß1 in serum and T regulatory cell (Treg) percentage in peripheral blood of dogs with perianal tumours. Investigations were conducted on 32 male dogs of mixed breed. The animals were divided into 4 experimental groups and control group. The groups were established depending on the tumour malignancy degree and the type of dominant hormones. All measurements of serum cytokine concentrations were conducted by the use of commercial diagnostic ELISA kits. Treg lymphocyte percentage was measured by flow cytometry. In both groups with benign tumours cytokine levels decreased during therapy, whilst in groups with malignant tumors, in spite of applying anti-tumour therapy, concentrations of cytokines in serum markedly increased. The mean percentage of Treg lymphocytes in dogs with benign tumours (group I and II) was significantly lower than the mean percentage of these cells in control group at all time points, but after applying of anti-hormonal therapy, the significant increase of Treg percentage was observed compared to baseline values. By contrast, in both groups with malignant tumours (group III and IV), the mean percentage of Treg lymphocytes was significantly higher at the beginning of the experiment comparing with the control group as well as both groups with benign tumours and this percentage increased during anti-tumour therapy. The results of this study suggest that monitoring changes in cytokine serum concentrations and Treg percentage in the bloodstream during anti-hormonal therapy may constitute a subsidiary marker in the monitoring of therapy effectiveness, in prognosis the outcome of a disease or in differentiating tumour degree of malignancy.

The antimicrobial peptide pardaxin exerts potent anti-tumor activity against canine perianal gland adenoma.

Pardaxin is an antimicrobial peptide of 33 amino acids, originally isolated from marine fish. We previously demonstrated that pardaxin has anti-tumor activity against murine fibrosarcoma, both in vitro and in vivo. In this study, we examined the anti-tumor activity, toxicity profile, and maximally-tolerated dose of pardaxin treatment in dogs with different types of refractory tumor. Local injection of pardaxin resulted in a significant reduction of perianal gland adenoma growth between 28 and 38 days post-treatment. Surgical resection of canine histiocytomas revealed large areas of ulceration, suggesting that pardaxin acts like a lytic peptide. Pardaxin treatment was not associated with significant variations in blood biochemical parameters or secretion of immune-related proteins. Our findings indicate that pardaxin has strong therapeutic potential for treating perianal gland adenomas in dogs. These data justify the veterinary application of pardaxin, and also provide invaluable information for veterinary medicine and future human clinical trials.

VEGF and 17-ß-estradiol levels after tamoxifen administration in canine hepatoid gland adenomas and hepatoid gland epitheliomas.

The aim of the present study was to determine the serum levels of vascular endothelial growth factor in animals in the course of pharmacological treatment against perianal gland neoplasms. Research material comprised of tumor tissue samples obtained from 30 dogs and blood drawn from dogs with tumors and control group animals. The neoplasm type was determined in accordance with the relevant WHO classification. Immunoenzimatic determination of VEGF levels in the blood sera was performed. In all studied animals suffering from tumors, pharmacological tamoxifen treatment was administered, at a dosage of 2 mg/kg bodyweight. The medication was administered for one month. In order to monitor the serum levels of 17-ß-estradiol and VEGF, blood was drawn from sick animals three times (on the day of the diagnosis, as well as at one and six months after treatment). The VEGF determination assay was performed in accordance with the manufacturer's guidelines for the ELISA. In the studied group, 12 animals were diagnosed with hepatoid gland adenomas and 18 with hepatoid gland epitheliomas. Elevated VEGF levels were observed in the group of dogs with hepatoid gland ephithelioma in comparison with the control group. In the studied groups, a decrease in serum VEGF level and a complete remission of neoplastic lesions was observed one month after administering tamoxifen. The VEGF levels in dogs with hepatoid gland adenoma continued to decline with time. In the case of dogs with hepatoid gland epithelioma, after the initial drop one month after treatment, a rapid increase of the growth factor level was observed, which was significantly higher in animals suffering a relapse of the neoplastic disease (50% of dogs). A significant correlation was observed between 17-ß-estradiol and VEGF levels in dogs with hepatoid gland epithelioma on the day of diagnosis (Rxy=0.64, p<0.05) and six months after treatment (Rxy=0.54, p<0.05). Conclusion: VEGF overexpresion observed six months after tamoxifen treatment may constitute a prognostic factor in terms of the progression of the neoplastic process. The level of VEGF correlates with the level of 17-ß-estradiol in serum. Apart from anti-estrogen effects, tamoxifen also demonstrates anti-angiogenic activity.

Electrolyte disturbances and cardiac arrhythmias in a dog following pamidronate, calcitonin, and furosemide administration for hypercalcemia of malignancy.

A 13-year-old dog was diagnosed with hypercalcemia of malignancy associated with adenocarcinoma of the anal sacs. Hypercalcemia was treated with intravenous (IV) 0.9% sodium chloride (NaCl), furosemide, calcitonin, and pamidronate. Hypomagnesemia was documented by 72 hours following a single, IV dose of pamidronate. The dog subsequently underwent surgery to remove the primary tumors, and multiple cardiac arrhythmias occurred during anesthesia. This case documents electrolyte abnormalities in a dog following treatment with pamidronate in conjunction with other therapies used to manage hypercalcemia. The authors postulate that hypomagnesemia may have contributed to the arrhythmias that occurred during anesthesia. Electrolyte abnormalities should be anticipated and corrected following pamidronate therapy in canine patients.