TIAM1-RAC1 promote small-cell lung cancer cell survival through antagonizing Nur77-induced BCL2 conformational change.
Cell Rep
; 37(6): 109979, 2021 11 09.
Article
em En
| MEDLINE
| ID: mdl-34758330
ABSTRACT
Small-cell lung cancer (SCLC), an aggressive neuroendocrine malignancy, has limited treatment options beyond platinum-based chemotherapy, whereafter acquired resistance is rapid and common. By analyzing expression data from SCLC tumors, patient-derived models, and established cell lines, we show that the expression of TIAM1, an activator of the small GTPase RAC1, is associated with a neuroendocrine gene program. TIAM1 depletion or RAC1 inhibition reduces viability and tumorigenicity of SCLC cells by increasing apoptosis associated with conversion of BCL2 from its pro-survival to pro-apoptotic function via BH3 domain exposure. This conversion is dependent upon cytoplasmic translocation of Nur77, an orphan nuclear receptor. TIAM1 interacts with and sequesters Nur77 in SCLC cell nuclei and TIAM1 depletion or RAC1 inhibition promotes Nur77 translocation to the cytoplasm. Mutant TIAM1 with reduced Nur77 binding fails to suppress apoptosis triggered by TIAM1 depletion. In conclusion, TIAM1-RAC1 signaling promotes SCLC cell survival via Nur77 nuclear sequestration.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Biomarcadores Tumorais
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Regulação Neoplásica da Expressão Gênica
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Proteínas Proto-Oncogênicas c-bcl-2
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Proteínas rac1 de Ligação ao GTP
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Carcinoma de Pequenas Células do Pulmão
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Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares
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Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Female
/
Humans
Idioma:
En
Revista:
Cell Rep
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Reino Unido