Irreversible JNK blockade overcomes PD-L1-mediated resistance to chemotherapy in colorectal cancer.
Oncogene
; 40(32): 5105-5115, 2021 08.
Article
em En
| MEDLINE
| ID: mdl-34193942
ABSTRACT
Colorectal cancer (CRC) cells have low or absent tumor cell PD-L1 expression that we previously demonstrated can confer chemotherapy resistance. Here, we demonstrate that PD-L1 depletion enhances JNK activity resulting in increased BimThr116 phosphorylation and its sequestration by MCL-1 and BCL-2. Activated JNK signaling in PD-L1-depeted cells was due to reduced mRNA stability of the CYLD deubiquitinase. PD-L1 was found to compete with the ribonuclease EXOSC10 for binding to CYLD mRNA. Thus, loss of PD-L1 promoted binding and degradation of CYLD mRNA by EXOSC10 which enhanced JNK activity. An irreversible JNK inhibitor (JNK-IN-8) reduced BimThr116 phosphorylation and unsequestered Bim from MCL-1 and BCL-2 to promote apoptosis. In cells lacking PD-L1, treatment with JNK-IN-8, an MCL-1 antagonist (AZD5991), or their combination promoted apoptosis and reduced long-term clonogenic survival by anticancer drugs. Similar effects of the JNK inhibitor on cell viability were observed in CRC organoids with suppression of PD-L1. These data indicate that JNK inhibition may represent a promising strategy to overcome drug resistance in CRC cells with low or absent PD-L1 expression.
Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
/
Tipos_de_cancer
/
Colon_e_reto
Base de dados:
MEDLINE
Assunto principal:
Resistencia a Medicamentos Antineoplásicos
/
Proteínas Quinases JNK Ativadas por Mitógeno
/
Antígeno B7-H1
/
Antineoplásicos
Limite:
Humans
Idioma:
En
Revista:
Oncogene
Assunto da revista:
BIOLOGIA MOLECULAR
/
NEOPLASIAS
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Estados Unidos