CMTM6 maintains the expression of PD-L1 and regulates anti-tumour immunity.
Nature
; 549(7670): 101-105, 2017 09 07.
Article
em En
| MEDLINE
| ID: mdl-28813417
ABSTRACT
Cancer cells exploit the expression of the programmed death-1 (PD-1) ligand 1 (PD-L1) to subvert T-cell-mediated immunosurveillance. The success of therapies that disrupt PD-L1-mediated tumour tolerance has highlighted the need to understand the molecular regulation of PD-L1 expression. Here we identify the uncharacterized protein CMTM6 as a critical regulator of PD-L1 in a broad range of cancer cells, by using a genome-wide CRISPR-Cas9 screen. CMTM6 is a ubiquitously expressed protein that binds PD-L1 and maintains its cell surface expression. CMTM6 is not required for PD-L1 maturation but co-localizes with PD-L1 at the plasma membrane and in recycling endosomes, where it prevents PD-L1 from being targeted for lysosome-mediated degradation. Using a quantitative approach to profile the entire plasma membrane proteome, we find that CMTM6 displays specificity for PD-L1. Notably, CMTM6 depletion decreases PD-L1 without compromising cell surface expression of MHC class I. CMTM6 depletion, via the reduction of PD-L1, significantly alleviates the suppression of tumour-specific T cell activity in vitro and in vivo. These findings provide insights into the biology of PD-L1 regulation, identify a previously unrecognized master regulator of this critical immune checkpoint and highlight a potential therapeutic target to overcome immune evasion by tumour cells.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Antígeno B7-H1
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Proteínas de Membrana
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Neoplasias
Tipo de estudo:
Prognostic_studies
Limite:
Animals
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Female
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Humans
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article