G3BP1 knockdown sensitizes U87 glioblastoma cell line to Bortezomib by inhibiting stress granules assembly and potentializing apoptosis

Autor(es):Mostrar menos -

Bittencourt, L. F. F. ^[1] ; Negreiros-Lima, G. L. ^[2] ; Sousa, L. P. ^[2] ; Silva, A. G. ^[3] ; Souza, I. B. S. ^[3] ; Ribeiro, R. I. M. A. ^[3] ; Dutra, M. F. ^[1] ; Silva, R. F. ^[1] ; Dias, A. C. F. ^[1] ; Soriani, F. M. ^[4] ; Martins, W. K. ^[5] ; Barcelos, L. S. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Minas Gerais, ICB, Dept Fisiol & Biofis, Av Antonio Carlos 6627, BR-31270901 Belo Horizonte, MG - Brazil

^[2] Univ Fed Minas Gerais, Fac Farm, Belo Horizonte, MG - Brazil

^[3] Univ Fed Sao Joao Del Rei UFSJ, Lab Patol Expt, Sao Joao Del Rei, MG - Brazil

^[4] Univ Fed Minas Gerais, Inst Ciencias Biol, Dept Biol Geral, Belo Horizonte, MG - Brazil

^[5] Univ Anhanguera Sao Paulo, Posgrad Stricto Sensu & Pesquisa, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF NEURO-ONCOLOGY; v. 144, n. 3, p. 463-473, SEP 2019.
• Citações Web of Science: 1

Resumo

Introduction Glioblastoma multiforme (GBM) is the most lethal form of gliomas. New therapies are currently in development to tackle treatment limitations such as chemotherapy resistance. One mechanism of resistance may be the stress granules (SG) assembly, a stress-related cellular response that allows cells to recruit and protect mRNAs during stress. SG are composed of various proteins, being G3BP1 a core element that enucleates and results in SG assembly. Here, we aimed to evaluate the effects of inhibiting the G3PB1 expression in the chemotherapeutical-induced cell death of the U87 glioblastoma cell line. Materials and Methods G3BP1 mRNA and protein expression were modulated with short-interference RNA (siRNA). The viability of U87 cells after Bortezomib (BZM), a proteasome inhibitor, and Temozolomide (TMZ), an alkylating agent, was assessed by MTT assay. Apoptosis was evaluated by staining cells with Annexin-V/7-AAD and analyzing by flow cytometry. Caspase-3 activation was evaluated by immunoblotting. The chorioallantoic membrane in vivo assay was used to evaluate angiogenesis. Results When G3BP1 was knocked-down, the SG assembly was reduced and the BZM-treated cells, but not TMZ-treated cells, had a significant increase in the apoptotic response. Corroborating this data, we observed increased Caspase-3 activation in the BZM-treated and G3BP1-knocked-down cells when compared to vehicle-treated and scramble-transfected cells. Worth mentioning, the conditioned culture medium of G3BP1-knocked-down BZM-treated cells inhibited angiogenesis when compared to controls. Conclusion Our data suggest G3BP1 knockdown diminishes SG formation and stimulates BZM-induced apoptosis of U87 cells in vitro, in addition to inhibiting glioblastoma-induced angiogenesis in vivo. (AU)

• Processo FAPESP: 13/07937-8 - Redoxoma
• Beneficiário: Ohara Augusto
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 16/07642-6 - A ativação/inibição da autofagia pelos triterpenóides e o impacto da interação em membranas: implicações terapêuticas antitumorais
• Beneficiário: Waleska Kerllen Martins Gardesani
• Modalidade de apoio: Auxílio à Pesquisa - Regular