Translation initiation factor eIF4F modifies the dexamethasone response in multiple myeloma.
Proc Natl Acad Sci U S A
; 111(37): 13421-6, 2014 Sep 16.
Article
em En
| MEDLINE
| ID: mdl-25197055
ABSTRACT
Enhanced protein synthesis capacity is associated with increased tumor cell survival, proliferation, and resistance to chemotherapy. Cancers like multiple myeloma (MM), which display elevated activity in key translation regulatory nodes, such as the PI3K/mammalian target of rapamycin and MYC-eukaryotic initiation factor (eIF) 4E pathways, are predicted to be particularly sensitive to therapeutic strategies that target this process. To identify novel vulnerabilities in MM, we undertook a focused RNAi screen in which components of the translation apparatus were targeted. Our screen was designed to identify synthetic lethal relationships between translation factors or regulators and dexamethasone (DEX), a corticosteroid used as frontline therapy in this disease. We find that suppression of all three subunits of the eIF4F cap-binding complex synergizes with DEX in MM to induce cell death. Using a suite of small molecules that target various activities of eIF4F, we observed that cell survival and DEX resistance are attenuated upon eIF4F inhibition in MM cell lines and primary human samples. Levels of MYC and myeloid cell leukemia 1, two known eIF4F-responsive transcripts and key survival factors in MM, were reduced upon eIF4F inhibition, and their independent suppression also synergized with DEX. Inhibition of eIF4F in MM exerts pleotropic effects unraveling a unique therapeutic opportunity.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Dexametasona
/
Fator de Iniciação 4F em Eucariotos
/
Mieloma Múltiplo
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2014
Tipo de documento:
Article