Mammary tumours are the most common malignancy diagnosed in female dogs and a significant cause of mortality and morbidity in this species. Carbohydrate antigen (CA) 15–3 is a mucinous glycoprotein aberrantly over-expressed in human mammary neoplasms and one of the most widely used serum tumour markers in women with breast cancer. The aim of this study was to investigate the antigenic analogies of human and canine CA 15–3 and to assess its expression in canine mammary cancer tissues and cell lines. Immunohistochemical expression of CA 15–3 was evaluated in 7 canine mammary cancer cell lines and 50 malignant mammary tumours. As a positive control, the human breast carcinoma cell line MCF7 and tissue were used. To assess CA 15–3 staining, a semi-quantitative method was applied. To confirm the specificity and cross-reactivity of an anti-human CA 15–3 antibody to canine tissues, an immunoblot analysis was performed. We also investigated serum CA 15–3 activity to establish whether its expression could be assigned to several tumour characteristics to evaluate its potential use as a serum tumour marker in the canine mammary oncology field.

Feline injection-site sarcomas are malignant skin tumors of mesenchymal origin, the treatment of which is a challenge for veterinary practitioners. Methods of treatment include radical surgery, radiotherapy and chemotherapy. The most commonly used cytostatic drugs are cyclophosphamide, doxorubicin and vincristine. However, the use of cytostatics as adjunctive treatment is limited due to their adverse side-effects, low biodistribution after intravenous administration and multidrug resistance. Colloid gold nanoparticles are promising drug delivery systems to overcome multidrug resistance, which is a main cause of ineffective chemotherapy treatment. The use of colloid gold nanoparticles as building blocks for drug delivery systems is preferred due to ease of surface functionalization with various molecules, chemical stability and their low toxicity. Stability and structure of the glutathione-stabilized gold nanoparticles non-covalently modified with doxorubicin (Au-GSH-Dox) was confirmed using XPS, TEM, FT-IR, SAXRD and SAXS analyses. MTT assay, Annexin V and Propidium Iodide Apoptosis assay and Rhodamine 123 and Verapamil assay were performed on 4 feline fibrosarcoma cell lines (FFS1WAW, FFS1, FFS3, FFS5). Statistical analyses were performed using Graph Pad Prism 5.0 (USA). A novel approach, glutathione-stabilized gold nanoparticles (4.3 +/- 1.1 nm in diameter) non-covalently modified with doxorubicin (Au-GSH-Dox) was designed and synthesized. A higher cytotoxic effect (p<0.01) of Au-GSH-Dox than that of free doxorubicin has been observed in 3 (FFS1, FFS3, FFS1WAW) out of 4 feline fibrosarcoma cell lines. The effect has been correlated to the activity of glycoprotein P (main efflux pump responsible for multidrug resistance). The results indicate that Au-GSH-Dox may be a potent new therapeutic agent to increase the efficacy of the drug by overcoming the resistance to doxorubicin in feline fibrosarcoma cell lines. Moreover, as doxorubicin is non-covalently attached to glutathione coated nanoparticles the synthesized system is potentially suitable to a wealth of different drug molecules.

Background: In both women and female dogs, the most prevalent type of malignant neoplasm is the spontaneous mammary tumor. In dogs, half of these are malignant. The treatment of choice for the canine patients is surgical mastectomy. Unfortunately, it often fails in high-risk, locally invasive mammary tumors as of during the time of the surgery the micro-metastases are present. Moreover, there are neither large studies conducting to prove of the benefit from the chemotherapy in dogs nor established chemotherapy treatment protocols available. Additionally, the effectiveness of each individual chemotherapeutic agent and drug resistance of canine mammary cancer have not yet been characterized. That has become the aim of our study, to assess the expression of PGP, BCRP, MRP1 and MRP3 in canine mammary cancer cell lines and to investigate their role in cancer resistance to vinblastine, cisplatin and cyclophosphamide with using RNAi approach. Results: The results suggested that in canine mammary cancer, the vinblastine efflux was mediated by PGP and MRP1 proteins, cisplatin efflux was mediated by all four examined efflux pumps (PGP, BCRP, MRP1 and MRP3), whereas cyclophosphamide resistance was related to BCRP activity. RNAi silencing of these efflux pumps significantly decreased IC50 doses of the examined drugs in canine mammary carcinoma cells. Conclusions: Our results have indicated the treatment of cells involving use of the siRNA targeting efflux pumps could be a beneficial approach in the future.

Several years ago, the presence of macrophages in the tumor microenvironment was thought to be an inflammatory response to kill the cancer cells. Now, this is clear that the inflammatory cells that exit blood vessels and migrate to the tumor tissue play an important role in cancer progression. Various cells present in the tumor microenvironment enhance cancer growth and invasiveness by secretion of tumor-enhancing products. That is why tumors should not be treated as only aggregates of cancer cells but as separate structures. Macrophages form a major component of the inflammatory infiltration in tumors, where they are termed tumor-associated macrophages (TAMs). To the best of our knowledge, up-to-date there were no studies on tumor associated macrophages and the role of the tumor microenvironment in tumor invasion/metastasis in dogs. This is the first study performed to asses if the number of TAMs and expression of MCSF-R (macrophages colony stimulating factor receptor) and CD14 (LPS co-receptor) are associated with the grade of tumor malignancy and its ability to metastasize. We have performed immunohistochemical analysis of 50 canine mammary adenocarcinomas of various grade of malignancy (1^st, 2^nd, 3^rd) and tumors that gave local or distant metastases. The results indicate that in dogs, similarly to humans and mice, the number of tumor associated macrophages is related to the cancer ability to metastasize. Our results also indicate that the expression of MCSF-R and, what is particularly new finding, CD14 is associated with tumor malignancy and its ability to metastasize. Hence, these molecules play a role in tumor progression, metastasis and microenvironment interactions. These results show that in dogs we should treat the tumor as a whole organ rather than just try to eliminate the cancer cells.

In this study, the influence of new multi-strain synbiotics on chicken growth performance, hematology, serum biochemistry and immunity was explored. Each synbiotic preparation (A, B and C) comprised three, four or five strains of Lactobacillus sp., respectively, as well as S. cerevisiae and inulin. All strains used in the synbiotics originated from wild-type strains from animal farms in Poland. Six groups of chickens, ROSS 308 line, were fed with three different synbiotics at a dose of 0.5 g/1 kg of feed. Body weight, as well as the biochemical and hematological parameters of the animals in each study group, were determined on the 7th, 14th, 28th and 42nd day of life. Body weight on day 42 differed between groups and was the highest in control group. This group also had the highestfeed conversion ratio (FCR) value. All measured biochemical parameters were in the normal ranges for poultry; however, we observed a lower alkaline phosphatase (AP) concentration on day 7 in the groups fed with synbiotics, which correlated with a lower level of triglycerides in those groups. The aspartate transaminase (AST) concentration was significantly lower in all groups on day 42 in comparison with the control. On day 7, the control group showed the highest concentration of Ca, K and P. Other parameters did not differ significantly throughout the experiment. All groups showed a similar tendency of increase in the red blood cells (RBC) count according to the age of the birds. Every white blood cells (WBC) population showed differences in the proportions between T and B lymphocytes. The T cell and monocyte counts increased until day 28 in all groups. The results showed that our newly developed synbiotic formulas do not have any unfavorable influence on chicken health and may modulate immune response and biochemical parameters. However, this hypothesis needs to be evaluated in future experiments.