LincRNA-immunity landscape analysis identifies EPIC1 as a regulator of tumor immune evasion and immunotherapy resistance
Menée à l'aide de données du projet "The Cancer Genome Atlas" et du portail "Genomic Data Commons" portant au total sur 9 626 échantillons tumoraux et menée à l'aide de lignées cellulaires et de modèles murins, cette étude identifie un mécanisme par lequel le long ARN intergénique non codant EPIC1 induit l'échappement immunitaire des cellules cancéreuses ainsi que la résistance de ces dernières à l'immunothérapie
Through an integrative analysis of the lincRNA expression and tumor immune response in 9,626 tumor samples across 32 cancer types, we developed a lincRNA-based immune response (LIMER) score that can predict the immune cells infiltration and patient prognosis in multiple cancer types. Our analysis also identified tumor-specific lincRNAs, including EPIC1, that potentially regulate tumor immune response in multiple cancer types. Immunocompetent mouse models and in vitro co-culture assays demonstrated that EPIC1 induces tumor immune evasion and resistance to immunotherapy by suppressing tumor cell antigen presentation. Mechanistically, lincRNA EPIC1 interacts with the histone methyltransferase EZH2, leading to the epigenetic silencing of IFNGR1, TAP1/2, ERAP1/2, and MHC-I genes. Genetic and pharmacological inhibition of EZH2 abolish EPIC1’s immune-related oncogenic effect and its suppression of interferon-γ signaling. The EPIC1-EZH2 axis emerges as a potential mechanism for tumor immune evasion that can serve as therapeutic targets for immunotherapy.