Efeito da via de TLR4 na resposta ao tratamento quimioterápico em células tumorais de cabeça e pescoço
Data
2023-06-26
Tipo
Trabalho de conclusão de curso
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Resumo
O Toll Like Receptor 4 (TLR4), receptor do sistema imune inato, possui um papel ambíguo quando ativado em neoplasias, sendo capaz de induzir a proliferação celular, ou ainda atuar inibindo o tumor, dependendo de fatores como tipo celular ou mutações como exemplo na proteína p53. A p53 é conhecida por controlar o ciclo celular e induzir à apoptose em resposta a danos no DNA, e é mutada grande parte dos tumores de cabeça e pescoço. Nesse tipo específico de tumores há diferentes fatores responsáveis por desencadear o processo tumorigênico, entre eles o HPV. O objetivo do trabalho é analisar o efeito da ativação e inibição da via de TLR4 nas respostas ao tratamento quimioterápico em linhagens celulares de tumores de cabeça e pescoço apresentando diferentes status de HPV e alterações na proteína p53. Foram utilizadas 3 linhagens celulares provenientes de tumores escamosos de cabeça e pescoço, sendo elas: SCC078, apresentando mutação em p53 e sem genoma de HPV; SCC143, sem mutações em p53 e sem genoma de HPV; e SCC154, sem alterações em p53 e apresentando genoma de HPV16. As análises incluíram ensaios de proliferação celular, análises de expressão gênica por RT-q-PCR e análise de produção de espécies reativas a oxigênio por citometria de fluxo. Os resultados mostraram um aumento do número de células nas amostras estimuladas com LPS, assim como uma redução do número de células no tratamento com TAK242. Já as análises de expressão gênica evidenciaram um aumento na produção de IL-6 na combinação da TAK com cisplatina na SCC154, e um aumento de SOD2 no tratamento de TAK com cisplatina na SCC78. Os ensaios de espécies reativas de oxigênios (ROS) apresentaram resultados inconsistentes, o que não permitiu uma conclusão sobre o efeito dos tramentos na produção de ROS nas 3 linhagens. No entanto, mostramos que a modulação da atividade do TLR4 impacta na proliferação celular além de alterar a expressão gênicas nas linhagens de cabeça e pescoço, sendo assim um potencial alvo terapêutico nesse tipo tumoral.
Toll Like Receptor 4 (TLR4), a receptor of the innate immune system, has an ambiguous role when activated in neoplasms, being capable of inducing cell proliferation, or even acting to inhibit the tumor, depending on factors such as cell type or mutations such as p53 protein. p53 is known to control the cell cycle and induce apoptosis in response to DNA damage, and is mutated in most head and neck tumors. In this specific type of tumors there are different factors responsible for triggering the tumorigenic process, among them HPV. This study aimed to analyze the effect of TLR4 pathway activation and inhibition on responses to chemotherapy in cell lines of head and neck tumors with different HPV status and changes in p53 protein. Three cell lines from squamous head and neck tumors were used, namely: SCC078, presenting mutation in p53 and no HPV genome; SCC143, no mutations in p53 and no HPV genome; and SCC154, no alterations in p53 and presenting HPV genome16. The analyses included cell proliferation assays, gene expression analyses by RTqPCR, and analysis of reactive oxygen species production by flow cytometry. In the strains studied a response pattern to the drugs used to activate (LPS) and inhibit (TAK242) TLR4 could be observed. The results showed an increase in cell number in the samples stimulated with LPS, as well as a reduction in cell number in the TAK242 treatment. Gene expression analyses showed an increase in IL6 production in the combination of TAK + cisplatin in SCC154, and an increase in SOD2 in the treatment with TAK + cisplatin in SCC78. ROS assays results were inconsistent, not allowing the conclusion on the effect of TLR4 on ROS production in the three cell lines studied. It was possible to assess that TLR4 had an effect on proliferation and modulation of gene expression in the studied strains.
Toll Like Receptor 4 (TLR4), a receptor of the innate immune system, has an ambiguous role when activated in neoplasms, being capable of inducing cell proliferation, or even acting to inhibit the tumor, depending on factors such as cell type or mutations such as p53 protein. p53 is known to control the cell cycle and induce apoptosis in response to DNA damage, and is mutated in most head and neck tumors. In this specific type of tumors there are different factors responsible for triggering the tumorigenic process, among them HPV. This study aimed to analyze the effect of TLR4 pathway activation and inhibition on responses to chemotherapy in cell lines of head and neck tumors with different HPV status and changes in p53 protein. Three cell lines from squamous head and neck tumors were used, namely: SCC078, presenting mutation in p53 and no HPV genome; SCC143, no mutations in p53 and no HPV genome; and SCC154, no alterations in p53 and presenting HPV genome16. The analyses included cell proliferation assays, gene expression analyses by RTqPCR, and analysis of reactive oxygen species production by flow cytometry. In the strains studied a response pattern to the drugs used to activate (LPS) and inhibit (TAK242) TLR4 could be observed. The results showed an increase in cell number in the samples stimulated with LPS, as well as a reduction in cell number in the TAK242 treatment. Gene expression analyses showed an increase in IL6 production in the combination of TAK + cisplatin in SCC154, and an increase in SOD2 in the treatment with TAK + cisplatin in SCC78. ROS assays results were inconsistent, not allowing the conclusion on the effect of TLR4 on ROS production in the three cell lines studied. It was possible to assess that TLR4 had an effect on proliferation and modulation of gene expression in the studied strains.
Descrição
Citação
Cruz, K. A. S. Efeito da via de TLR4 na resposta ao tratamento quimioterápico em células tumorais de cabeça e pescoço. 2023. 40 f. Trabalho de conclusão de curso (Graduação em Ciências Biológicas) - Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, Diadema, 2023.