AHR mediates the aflatoxin B1 toxicity associated with hepatocellular carcinoma.
Signal Transduct Target Ther
; 6(1): 299, 2021 08 09.
Article
em En
| MEDLINE
| ID: mdl-34373448
ABSTRACT
Aflatoxin exposure is a crucial factor in promoting the development of primary hepatocellular carcinoma (HCC) in individuals infected with the hepatitis virus. However, the molecular pathways leading to its bioactivation and subsequent toxicity in hepatocytes have not been well-defined. Here, we carried out a genome-wide CRISPR-Cas9 genetic screen to identify aflatoxin B1 (AFB1) targets. Among the most significant hits was the aryl hydrocarbon receptor (AHR), a ligand-binding transcription factor regulating cell metabolism, differentiation, and immunity. AHR-deficient cells tolerated high concentrations of AFB1, in which AFB1 adduct formation was significantly decreased. AFB1 triggered AHR nuclear translocation by directly binding to its N-terminus. Furthermore, AHR mediated the expression of P450 induced by AFB1. AHR expression was also elevated in primary tumor sections obtained from AFB1-HCC patients, which paralleled the upregulation of PD-L1, a clinically relevant immune regulator. Finally, anti-PD-L1 therapy exhibited greater efficacy in HCC xenografts derived from cells with ectopic expression of AHR. These results demonstrated that AHR was required for the AFB1 toxicity associated with HCC, and implicate the immunosuppressive regimen of anti-PD-L1 as a therapeutic option for the treatment of AFB1-associated HCCs.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Receptores de Hidrocarboneto Arílico
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Carcinoma Hepatocelular
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Antígeno B7-H1
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Neoplasias Hepáticas
Tipo de estudo:
Prognostic_studies
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Risk_factors_studies
Limite:
Animals
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Humans
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article