Avaliação da atividade antitumoral de compostos n-fenilpiperazínicos em linhagem tumoral K562

Detalhes bibliográficos
Ano de defesa: 2016
Autor(a) principal: Santos, Thaís Rosa Marques dos lattes
Orientador(a): Valadares, Marize Campos lattes
Banca de defesa: Valadares, Marize Campos, Diniz, Danielle Guimarães Almeida, Oliveira, Gisele Augusto Rodrigues de
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Goiás
Programa de Pós-Graduação: Programa de Pós-graduação em Ciências Farmacêuticas (FF)
Departamento: Faculdade Farmácia - FF (RG)
País: Brasil
Palavras-chave em Português:
Palavras-chave em Inglês:
Área do conhecimento CNPq:
Link de acesso: http://repositorio.bc.ufg.br/tede/handle/tede/6756
Resumo: Although the efforts employed by scientific community to discover new anticancer therapies suitable to the increasing cancer incidence and multidrug resistance, its necessary to develop more selective and target driven drugs. Therefore, in this work we have done a screening with LQFM030 analogues, which is a Nutlin-1 analogue, aiming to evaluate their cytotoxic potential. Furthermore, we have evaluated the cytotoxicity, the morphological alterations and the cell death induction mechanisms of the compound LQFM166 in leukemia cell line K562. In parallel, we have investigated the security profile of the compound upon 3T3 basal cell line to estimate its LD50 and the Selectivity Index. The cytotoxicity assays included the tetrazolium salt (MTT) reduction and the Neutral Red Uptake assays, to assess the cytotoxicity of LQFM166 in K562 and 3T3 cell lines, respectively. The investigation of cell death induction mechanisms was carried out using flow cytometry, whereby we have evaluated the cells biochemistry parameters, including cell cycle progression, phosphatidylserine externalization, caspases 3/7, 8 and 9 activity, cytochrome c release from mitochondria, p21, p27, Bax, Bcl-2, cyclin-B1 and NFkB expression, using specific labeling for each assay. Data were analyzed by t test and the difference between control and treated groups averages was considered statistically significant when p<0,05. Regarding leukemia cell line K562, the compound LQFM166 was cytotoxic, showing a dose-time-dependent profile. Morphological alterations were observed after treatment with the compound at cellular and nuclear levels, which corroborate with apoptotic cell death. Additionally, treatment with the IC50 for 48 hours has promoted cellular and molecular changes that characterize this process, including phosphatidylserine externalization, increase of caspases 3/7, 8 and 9 activity, expression of pro-apoptotic proteins Bax, p21and p27, as well as diminution of Bcl-2 and cyclin-B1. We have also observed increase of cytochrome-c release and NFkB expression. Concerning the security profile, the compound was considered relatively selective, once the IC50 found to basal cell line (185,3 µM) was the double of the obtained to leukemia cell line regarding the same time of exposure (56,76 µM). The outcomes allow us to conclude that LQFM166 was cytotoxic upon leukemia cells K562, promoting morphological and biochemical alterations that indicate apoptotic cell death induction.