Investigação dos efeitos do silenciamento das proteínas RhoA e RhoC na proliferação clonal de linhagens mieloides
Data
2023-11-24
Autores
Mendonça, Guilherme Ramos Sales de 
Orientadores
Lazarini, Mariana
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
A leucemia mieloide aguda (LMA) é um câncer de medula óssea altamente heterogêneo, caracterizado por desregulação bioquímica resultante de alterações moleculares em células-tronco e progenitoras do sistema hematopoiético. Estas alterações causam um bloqueio na diferenciação celular com acúmulo de células imaturas na medula óssea e/ou sangue periférico, comprometendo a produção de células sanguíneas. O tratamento da LMA em geral é inespecífico e está associado a baixas taxas de sobrevida. RhoA e RhoC são proteínas homólogas da família de Rho GTPases envolvidas em processos relacionados à organização do citoesqueleto, como proliferação celular, e estão desreguladas em cânceres humanos. Porém, as funções de RhoA e RhoC foram pouco exploradas em LMA. O objetivo deste trabalho foi investigar a participação das proteínas RhoA e RhoC no processo de proliferação de células leucêmicas. Para isso, foram avaliados os efeitos do silenciamento de RhoA e RhoC na proliferação clonal das linhagens celulares das séries mieloides U937 e OCI-AML3. O ensaio de proliferação clonal foi primeiramente padronizado nas células parentais e então realizado em células silenciadas com lentivírus específicos para inibição de RhoA ou RhoC. O silenciamento de RhoA causou redução significativa na capacidade de proliferação clonal de ambas as linhagens leucêmicas, enquanto o silenciamento de RhoC não causou mudanças significativas na proliferação clonal destas linhagens.
Acute Myeloid Leukemia (AML) is a highly heterogeneous bone marrow cancer, characterized by biochemical dysregulation that results from molecular changes in stem and progenitor cells of the hematopoietic system. These changes cause a block in cell differentiation with the accumulation of immature cells in the bone marrow and/or peripheral blood, compromising blood cell production. AML treatment is usually nonspecific and associated to low patient survival rates. RhoA and RhoC are homologous proteins of the protein family of Rho GTPases involved in cell processes related to the cytoskeleton organization, such as proliferation. RhoA and RhoC are dysregulated in human cancers, but their functions were not explored in AML. In this project, we investigated the role of RhoA and RhoC proteins in the proliferation of leukemia cells. Proliferation was evaluated in U937 and OCI-AML3 cell lines silenced for RhoA or RhoC. The proliferation assay was first standardized in parental cell lines and then performed in cells silenced with specific lentivirus for the inhibition of RhoA or RhoC. RhoA silencing caused a significant reduction in the clonal proliferation of both cell lines, while the silencing of RhoC changed the clonal proliferation capacity of these cells.
Acute Myeloid Leukemia (AML) is a highly heterogeneous bone marrow cancer, characterized by biochemical dysregulation that results from molecular changes in stem and progenitor cells of the hematopoietic system. These changes cause a block in cell differentiation with the accumulation of immature cells in the bone marrow and/or peripheral blood, compromising blood cell production. AML treatment is usually nonspecific and associated to low patient survival rates. RhoA and RhoC are homologous proteins of the protein family of Rho GTPases involved in cell processes related to the cytoskeleton organization, such as proliferation. RhoA and RhoC are dysregulated in human cancers, but their functions were not explored in AML. In this project, we investigated the role of RhoA and RhoC proteins in the proliferation of leukemia cells. Proliferation was evaluated in U937 and OCI-AML3 cell lines silenced for RhoA or RhoC. The proliferation assay was first standardized in parental cell lines and then performed in cells silenced with specific lentivirus for the inhibition of RhoA or RhoC. RhoA silencing caused a significant reduction in the clonal proliferation of both cell lines, while the silencing of RhoC changed the clonal proliferation capacity of these cells.