Branched-chain ketoacids secreted by glioblastoma cells via MCT1 modulate macrophage phenotype.
EMBO Rep
; 18(12): 2172-2185, 2017 12.
Article
em En
| MEDLINE
| ID: mdl-29066459
ABSTRACT
Elevated amino acid catabolism is common to many cancers. Here, we show that glioblastoma are excreting large amounts of branched-chain ketoacids (BCKAs), metabolites of branched-chain amino acid (BCAA) catabolism. We show that efflux of BCKAs, as well as pyruvate, is mediated by the monocarboxylate transporter 1 (MCT1) in glioblastoma. MCT1 locates in close proximity to BCKA-generating branched-chain amino acid transaminase 1, suggesting possible functional interaction of the proteins. Using in vitro models, we demonstrate that tumor-excreted BCKAs can be taken up and re-aminated to BCAAs by tumor-associated macrophages. Furthermore, exposure to BCKAs reduced the phagocytic activity of macrophages. This study provides further evidence for the eminent role of BCAA catabolism in glioblastoma by demonstrating that tumor-excreted BCKAs might have a direct role in tumor immune suppression. Our data further suggest that the anti-proliferative effects of MCT1 knockdown observed by others might be related to the blocked excretion of BCKAs.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Glioblastoma
/
Transportadores de Ácidos Monocarboxílicos
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Simportadores
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Aminoácidos de Cadeia Ramificada
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Macrófagos
Limite:
Humans
Idioma:
En
Revista:
EMBO Rep
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Alemanha