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Non-small cell lung cancer-associated Keap1 mutations lead to epigenetic reprogramming and tumorigenesis through CHD6 stabilization

ABSTRACT: The E3 ubiquitin ligase substrate recognition subunit Keap1 mediates the ubiquitination and degradation of the oxidative stress transcription factor NRF2. Approximately 30% of non-small cell lung cancers (NSCLCs) harbor inactivating mutations in Keap1 or activating mutations in NRF2, both of which lead to the stabilization of NRF2 and activation of the downstream antioxidant pathway. Recent studies have found that the oncogenic effects of Keap1 and NRF2 mutations are not entirely equivalent, suggesting that Keap1 may have other regulatory substrates. In previous work, we used affinity immunopurification and mass spectrometry to identify the epigenetic regulator CHD6 as a Keap1-interacting protein, with Keap1 mediating the ubiquitination and degradation of CHD6. NSCLC-derived Keap1 mutants lost the ability to bind and ubiquitinate CHD6. Additionally, CHD6 interacts with NRF2 and promotes the enrichment of NRF2 at the promoters of its target genes, enhancing their transcription.This project aims to elucidate the mechanism by which the abnormal accumulation of CHD6 protein, due to disruption of its Keap1-mediated degradation, drives epigenetic reprogramming in the context of Keap1-mutant NSCLC development and progression. The findings will provide a theoretical basis for the development of NRF2 pathway inhibitors targeting CHD6 as a drug target.

ORGANISM(S): Homo sapiens

PROVIDER: GSE284431 | GEO | 2025/01/01

REPOSITORIES: GEO

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