Immunohistochemical expression of multidrug resistance proteins and immune system markers in cats with alimentary lymphoma

• Grant number: 12/25485-4
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2013
• End date: August 31, 2015
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Sílvia Regina Ricci Lucas
• Grantee: Sílvia Regina Ricci Lucas
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Lymphomas belong to a group of malignancies that have in common their origin in lymphoreticular cells, manifesting in lymphoid tissues generally solids. As a systemic disease, cancer chemotherapy is routinely used in the treatment of lymphomas, and cellular resistance to antineoplastic agents is considered one of the most significant obstacles to effective treatment of malignancies in general. Many cellular resistance mechanisms that have the function of protecting cells from different tissues, are present in normal cells, but the exacerbation of such mechanisms in cancer cells leads to resistance to antineoplastic drugs and treatment failure. Thus, evaluation of the expression of different proteins related to multidrug resistance in cats with alimentary lymphoma may elucidate some conditions in which the immunoreactivity of these proteins by the neoplastic cell may interfere with response to chemotherapy and survival. Likewise, it is known that an imbalance in the immune system may facilitate the occurrence and spread of cancers. There is evidence that Tregs alter the effector function against tumors and result in T cell dysfunction in humans and dogs with cancer, so does the Th17 cells. Thus, objectives of this study are to evaluate the immunohistochemical expression of P-glycoprotein, MRP, LRP and metallothionein, and CD4, CD8, CD25 (IL-2), IL-17 and FOXP3 in cats with alimentary lymphoma, depending on the results, expression of these markers correlate with disease-free interval and overall survival. (AU)