Evaluation of hemostasis and their relationship to Vascular Endothelial Growth Factor (VEGF), microvessel density (factor VIII) and Platelet-Derived Growth Factor (PDGF) in mammary carcinomas of female dogs

• Grant number: 15/02798-5
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): September 01, 2015
• Effective date (End): August 31, 2016
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal researcher: Sabryna Gouveia Calazans
• Grantee: Aline Fernandes Vital
• Home Institution: Pró-Reitoria Adjunta de Pesquisa e Pós-Graduação. Universidade de Franca (UNIFRAN). Franca , SP, Brazil

Abstract

Breast tumors are the most frequently observed malignancies in dogs, and 50 to 70% are malignant. Neoplasms of epithelial origin (carcinomas) are the most frequently diagnosed, while mesenchymal origin (sarcomas), are considered rare. The mechanisms that lead to the development of hemostatic disorders in patients with malignancies involve the proteins of coagulation and fibrinolysis, in addition to platelets, which play an important role in tumor growth and progression. The incidence of carcinoma thrombocytosis in dogs is relatively high, in turn, platelets also secrete several growth factors such as vascular endothelial growth factor (PDGF) and can induce angiogenesis stimulating the production of vascular endothelial growth factor ( VEGF). This project continues the study previously conducted by the researchers involved. Previous research avaliouse hemostasis in dogs with different tumors. Between groups, breast tumors showed higher representation (n = 30). Additionally, there was a significant difference in fibrinogen values between histological grades. It was also possible to observe the strong presence of cases of thrombocytosis and thrombocytopenia in this group. In this new stage, knowing from the influence of platelets and coagulation disorders in the metastatic process, and on the evidence of the relationship between coagulation and angiogenesis, we intend to investigate this association in canine mammary carcinomas. For this, coagulagrama results of 50 bitches with mammary carcinoma and immunohistochemical technique will be considered for determination of VEGF marking, Factor VIII and PDGF in cancer. The animals will be divided into groups according to metastasis, histological type, and histological grade. According to the obtained results, and the distribution and degree of histological types found, statistical tests are applied in an attempt to find differences between the variables and the correlation between the results obtained by coagulation and by immunohistochemistry. ANOVA or Kruskal-Wallis test will compare between means in the sample groups for multiple comparisons; Student's t or Mann-Whitney for paired analysis. Spearman's test will be applied for correlation analysis. With the results of this study, the interaction between coagulation and angiogenesis will be better understood and its role in metastasis mechanism in breast carcinomas of female dogs.(AU)