Plasma levels of chemokines CCL2 and CXCL12 in female dogs with malignant mammary gland tumours without and with metastases.

The aim of this study was to evaluate the plasma levels of chemokines CCL2 and CXCL12 in female dogs with malignant mammary gland tumours without and with metastases. The concentrations of CCL2 and CXCL12 were determined in 25 female dogs with malignant mammary gland tumours (15 without metastases and 10 with metastases) and 10 healthy control animals using a specific canine ELISA assay. The mean plasma concentrations of CCL2 and CXCL12 were significantly higher (p<0.05) in the metastatic group compared to the control group. Moreover, the concentrations of these chemokines were markedly higher in the dogs with metastases than in those without metastases; however, a statistically significant difference was not found. The concentrations of both tested chemokines were numerically increased in the dogs with grade 2 and grade 3 carcinomas compared to the dogs with grade 1 carcinomas but the differences did not reach statistical significance. In conclusion, the results of our study demonstrate that plasma concentrations of chemokines CCL2 and CXCL12 are significantly increased in the dogs with metastatic malignant mammary gland tumours compared to the healthy dogs and show an upward trend compared to those without metastases. However, clarifying whether the increase of these chemokines is a cause or an effect of metastasis in female dogs with malignant mammary gland tumours as well as their potential role in metastatic process requires further research.

Plasma interleukin-1α and interleukin-8 in female dogs with non-metastatic and metastatic malignant mammary gland tumours.

In this study plasma concentrations of IL-1α and IL-8 in 29 female dogs with malignant mammary gland tumours (19 without metastasis and 10 with metastasis) and in 10 healthy control animals were determined. Concentrations of IL-1α and IL-8 were analysed using a specific canine ELISA assay. Mean plasma concentrations of IL-1α and IL-8 were significantly higher (p⟨0.05) in female dogs with both non-metastatic and metastatic malignant tumours compared to the healthy animals. The concentrations of both tested cytokines were significantly increased (p⟨0.05) in the dogs with metastasis. In female dogs with mammary carcinomas, the plasma concentration of IL-1α was significantly higher (p⟨0.05) in the animals with grade 3 tumours compared to the dogs with grade 1 tumours. The concentration of IL-8 was significantly higher (p⟨0.05) in the dogs with grade 3 tumours compared to that found in the animals with grade 1 and grade 2 tumours. A moderate correlation (r=0.433) was found between IL-1α and IL-8 concentrations in the female dogs. These findings suggest that increased malignancy and invasiveness of canine mammary tumours is associated with an increased production of IL-1α and IL-8 in the tumour microenvironment, which, in turn, leads to an increase in their circulating levels. This may indicate that circulating levels of the cytokines investigated could be considered as diagnostic and prognostic markers in canine malignant mammary tumours. However, further studies in this fields are needed.

Changes in serum neopterin and C-reactive protein concentrations in female dogs with mammary gland tumours.

The aim of this study was to measure serum neopterin and C-reactive protein (CRP) concen- trations in female dogs with mammary tumours and evaluate the association between the values of these indicators and some clinical characteristics of the tumour. Fifty three female dogs were used for this study, including 43 dogs with mammary gland tumours (10 benign and 33 malignant) and 10 healthy controls. The concentrations of neopterin and CRP were determined using the ELISA technique and commercial ELISA kits. The mean serum neopterin concentration in fe- male dogs with mammary tumours was lower than in healthy dogs, but significant difference was not found. Similarly, there were no significant differences in neopterin concentrations in female dogs based on tumour size, tumour ulceration and metastasis. The mean CRP concentration was significantly higher (p⟨0.05) in dogs with malignant tumours compared to dogs with benign tu- mours and control. Furthermore, serum CRP concentration was significantly higher (p⟨0.05) in dogs with metastatic malignant tumours compared to dogs with non-metastatic mammary tu- mours. The CRP concentration was significantly lower (p⟨0.05) in dogs with tumours less than 3 cm compared to those with larger tumours, and significantly higher in dogs with ulcerated tu- mours compared to those without ulceration. Our findings suggest that the neoplastic process in the mammary gland does not cause significant changes in serum neopterin concentrations in dogs. Higher concentrations of serum CRP in dogs with advanced stages of malignant tumours may suggest that CRP could be a potential prognostic marker in canine malignant mammary tu- mours, but this hypothesis needs further study.

Epidemiological Study of Canine Mast Cell Tumours According to the Histological Malignancy Grade.

The aim of the study was to identify significant relationships between the tumour malignancy grade and dogs' age, breed, sex, size, and location of mast cell tumours (MCTs). MCTs accounted for 13.27% of all diagnosed canine skin tumours. The highest incidence was recorded among Boxers, Labrador Retrievers, American Staffordshire Terriers, and Golden Retrievers. Statistical analysis revealed significantly higher probability of occurrence of the grade I mast cell tumour in the French Bulldog in the head, neck, torso, and limb regions, the grade-II mast cell tumour in Boxer, Doberman, Dachshund, shepherds, and setters in the scrotal region, and the grade III mast cell tumour in Shar-Pei in the axilla region. In the group of the oldest dogs aged 11-16, there was higher risk of development of MCTs grade II and III. Young dogs (aged 2-3 and 4-6) were found to be more prone to development of MCTs grade I. There was no correlation between MCTs grade and dogs' sex and size. To the authors' knowledge this is the first report on statistical relationships between the degree of mast cell tumour malignancy and dogs' phenotypic traits, age and tumour location. This analysis indicate predilections for development of the particular mast cell tumour malignancy degrees in certain dog breeds, age, and anatomical location.

Serum neopterin levels in female dogs with malignant mammary tumours.

In this study, we have determined serum neopterin levels in female dogs with primary malignant mammary tumours. The study involved 50 female dogs which had a malignant mammary tumours removed surgically (32 animals with carcinoma, 12 animals with sarcoma and 6 animals with carcinosarcoma) and 10 clinically healthy female dogs. Serum neopterin levels were determined using a commercial ELISA kit. The mean neopterin levels were lower in the malignant tumour groups than in healthy animals but differences were statistically significant only in carcinoma and sarcoma groups. The decrease of neopterin levels in animals with malignant mammary tumours may suggest their decreased cellular immunity. Moreover, it might indicate that decreased activity of cellular mechanisms of the anti-neoplastic response is one of the factors associated with the development and course of malignant mammary tumours in female dogs; however, further studies are necessary.

Prognostic value of regional lymph node status in canine mammary carcinomas.

In this study, we have determined the prognostic value of the presence of the micrometastases and metastases greater than 2 mm in the regional lymph nodes for bitches with mammary carcinomas. The study involved 51 dogs diagnosed with a single malignant epithelial tumour in the 4th or 5th mammary gland. All animals underwent regional mastectomy; the 4th and 5th mammary glands were removed together with the inguinal lymph node. The lymph nodes were examined immunohistochemically using the anti-cytokeratin antibody, clone AE1/AE3. The bitches were followed up every 6 months for 2 years after surgery to determine the disease-free survival (DFS) and overall survival (OS). The Kaplan-Meier analysis showed a statistically significant difference in DFS and OS only between the group of bitches without metastases and the group with lymph node metastases greater than 2 mm. No significant differences between these two groups versus bitches with lymph node micrometastases were found.

Tumor-associated carbohydrate antigens: Sialyl Lea and T/Tn antigens in canine mammary tumors.

Twenty-eight canine mammary tubulopapillary carcinomas and 14 simple adenomas were studied by immunohistochemistry for the expressions of the tumor-associated carbohydrate antigens. Sialyl Le(a) was detected in 71.42% of the malignant and 92.84% of the benign tumors. Staining with anti-T and anti-Tn monoclonal antibodies revealed that 85.70% of the tubulopapillary carcinomas expressed T and Tn antigens. In contrast, 50% of the adenomas did not express T antigen, and 42.85% of them were only weakly stained for this carbohydrate structure. In the case of Tn antigen, the majority (57.14%) of samples was weakly stained, and no binding was observed in 35.71% of the analyzed specimens. Comparison of average values of reaction intensity (IRS) scale for malignant versus benign tumors by the Mann-Whitney U-test revealed a significant relationship between T and Tn antigens expression and type (malignant vs. benign) mammary tumors. Based on the results obtained, it is suggested that each of the studied antigens can be treated as a tumor-associated antigen of canine mammary tumors. However, only the T and Tn antigens seem to be associated with malignant transformation of mammary gland cells and to be of potential value as diagnostic markers.

Oxidative stress parameters in bitches with mammary gland tumours.

The aim of the present study was to describe some of the oxidative stress parameters in bitches suffering from spontaneously occurring mammary gland tumours. The experiment involved 28 bitches which had mammary gland tumours removed surgically (15 bitches with malignant tumour and 13 with benign tumour) as well as 10 clinically healthy bitches. The activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were determined in haemolysates of erythrocytes derived from the animals. The concentrations of thiobarbituric acid reactive substances (TBARS), as well as -SH groups, were determined in blood plasma. GSH-Px activity was significantly higher in the malignant tumour group than in healthy animals. SOD activity was significantly higher in animals with tumours compared with the control group. Activities of both enzymes were higher in animals with malignant tumours than in benign groups, but the differences were not statistically significant. The concentrations of TBARS and -SH groups were similar in all examined groups. The increase of antioxidative enzyme activities in these animals may suggest the activation of antioxidative defence mechanisms in mammary gland carcinogenesis. Moreover, it might indicate the participation of oxidative stress in malignancies. Further experiments involving more animals, with more frequent sample collection and the use of other oxidative stress markers are necessary.

Studies on histogenesis of mixed tumours of the mammary gland in bitches.

The aim of the study was the immunohistochemical assessment of the reactivity of mixed tumours in bitches with special regard to myoepithelial cells and cartilage. The materials for study were 20 mixed tumours collected during surgery or autopsy. Paraffin-embedded sections were routinely stained with hematoxylin and eosin and HID method was also used. Immunohistochemical assays were made using the AB-Complex method with the use of monoclonal antibodies against: cytokeratin MNF-116, cytokeratin 19, vimentin, actin and S-100 protein. On the basis of the reactions, 5 types of myoepithelial origin cells transformed during the formation of cartilage cells were diagnosed.