Evaluation of the expression of the programmed death cellular ligand (pd-l1) and the cytotoxic and regulatory t cell infiltrates as prognostic factors in canine mammary tumors

• Grant number: 20/14891-8
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2021
• End date: June 30, 2023
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal Investigator: Ricardo de Francisco Strefezzi
• Grantee: Ingrid Kester Lima Silva
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Associated scholarship(s): 22/01207-7 - Histological classification and immunohistochemical evaluation of hormonal receptors, Ki67 and HER2 as prognostic factors in canine mammary carcinomas, BE.EP.MS

Abstract

Cancer has been reported as the main cause of death in dogs, overcoming infectious diseases. In dogs, mammary tumors are the most common, accounting for about 50% of cases. Studies to elucidate tumor pathogenesis and to improve cancer treatment and prevention are necessary. PD-1 is an immune checkpoint molecule expressed on the surface of T cell membranes. When it binds to its PD-L1 ligand, negative signals are propagated to T cells, a suppressive mechanism of great importance for controlling immunological responses. However, this protective mechanism can also be used by tumor cells, which can express the PD-L1 protein on their surfaces and evade immune response. PD-1/PD-L1 blockade with anti-PD-L1 antibodies is already used in humans in order to eliminate tumor cells. PD-1 and PD-L1 expressions have already been analyzed in several animal species, however, information about the expression of PD-L1 in dogs with naturally occurring cancer is scarce. Therefore, the investigation of these new prognostic markers is needed in veterinary medicine and could provide more accurate information about metastases, overall survival and disease-free interval. The objectives of this project are to characterize the expression of the programmed death cell ligand (PD-L1) and the cytotoxic and regulatory T cells populations as prognostic factors in canine mammary tumors. The expressions of PD-L1 and the infiltrates of T cells will be analyzed in 200 samples of mammary neoplasms of different histopathological types. The results will be compared with histological types and post-surgical survival. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

SILVA, Ingrid Kester Lima. Evaluation of expression of death programmed cell ligand (PD-L1) and cytotoxic and regulatory t-cell infiltrate as prognostic factors in mammary tumor of canine female. 2023. Master's Dissertation - Universidade de São Paulo (USP). Faculdade de Zootecnica e Engenharia de Alimentos (FZE/BT) Pirassununga.