Estudo de alterações em células Treg e TH17 no linfonodo drenante de animais com tumores

Detalhes bibliográficos
Ano de defesa: 2014
Autor(a) principal: Salin, Málvaro Maculan lattes
Orientador(a): Bonorino, Cristina Beatriz C. lattes
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul
Programa de Pós-Graduação: Programa de Pós-Graduação em Biologia Celular e Molecular
Departamento: Faculdade de Biociências
País: Brasil
Palavras-chave em Português:
Área do conhecimento CNPq:
Link de acesso: http://tede2.pucrs.br/tede2/handle/tede/6153
Resumo: Melanoma is one of the most aggressive malignant tumors, and its incidence has been increasing steadily in recent years. Usually in the early stages, treatment for melanoma is local surgery with reasonable efficiency. However, treatments such as chemotherapies for advanced melanoma have limited benefits, prolonging the patient's life in a few months. Thus the search for more effective therapies for melanoma is necessary. More recent studies suggest that tumor immune response conducted by subtypes of CD4+ T helper cells subsets have an important role in cancer control. According to tumor infiltrating Th17 and Treg cellsand the cytokines they secrete the tumor microenvironment profile may be suggested anti or pro-tumor activities or exerted by these cells. In this study, we investigated the transcriptional markers of CD4+Foxp3+ T cells and CD4+RORγt+ T cells in draining lymph nodes of animals throughout the melanoma tumor growth and evaluate whether the combined action of cisplatin (cis-diamino-dichloro-platin, CDDP) and TLR2 (peptidoglycan) or TLR3 (acid-Polyribosilic Polyribocytidilic) or TLR4 (lipopolysaccharide) agonists, can change these parameters. The animals were injected with melanoma cell line B16F10 and according tumor progression the tumor draining lymph node (TDLN) were excised for analysis of Treg and Th17 cells by flow cytometry. Furthermore, we analyzed the survival of animals treated with combined therapies. We found an increase in the percentage and absolute number of Th17 and Treg cells in TDLN according tumor progression, which was consistent with previous studies. Our results indicate that treatment with cisplatin promotes tumor growth by increasing Treg and Th17 cells. Treatment with CDDP plus TLR2 agonist significantly decreases the percentage of Th17 cells in TDLN. We demonstrated here, that combinated CDDP and TLR3 or TLR4 agonist therapy impairs tumor growth and modulate the frequency of these cells by decreasing the percentage of CD4+Foxp3+ T cells. In addition, this combination also showed a modest increase insurvivalof the melanoma bearing mice. These results showed that TLRs agonists may be used in combination with cisplatin as a potential adjuvant capable impair tumor growth in melanoma bearing mice.