Project description:Immune checkpoint blockade (ICB) therapy revolutionized cancer treatment, but many patients with impaired MHC-I expression remain refractory. Histone methylation was involved in anti-tumor immunity of ICB. However, the link between histone methylation and MHC-I regulation and the related mechanisms are poorly understood. Here we show that KDM5A, an H3K4 demethylase that is critical for MHC-I expression and associated antigen presentation capacity, induces robust immune response and enhances ICB efficacy. Mechanistically, KDM5A upregulates IFN-gamma/STAT1-mediated MHC-I expression via directly binding and suppressing Scos1 in tumor cells. The genes encoding the lysosomal cathepsins are recognized and up-regulated by KDM5A, resulting in enhanced antigen-presentation abilities of both tumor cells and dendritic cells. Furthermore, pharmacological enhancing KDM5A improves response to anti-PD-1 therapy. These investigations demonstrate that enhancing KDM5A triggers MHC-associated antigen presentation of both tumor cells and DCs simultaneously to boost antitumor immunity, thus represents a candidate ICB sensitizer.
Project description:Histone dimethyl transferase WHSC1 drives the transcription of MHC-I machinery in mouse and human colorectal cancer cells (CRCs); thus, WHSC1 downregulation potentiates CRCs to escape from cytotoxic CD8+ T cell responses. WHSC1 directly interacts with MHC-I transactivator, NLRC5 to selectively stimulate MHC-I gene expression. Thus, silencing Whsc1 diminished MHC-I level, impaired anti-tumor immunity and blunted immunotherapy efficacy.
Project description:Histone dimethyl transferase WHSC1 drives the transcription of MHC-I machinery in mouse and human colorectal cancer cells (CRCs); thus, WHSC1 downregulation potentiates CRCs to escape from cytotoxic CD8+ T cell responses. WHSC1 directly interacts with MHC-I transactivator, NLRC5 to selectively stimulate MHC-I gene expression. Thus, silencing Whsc1 diminished MHC-I level, impaired anti-tumor immunity and blunted immunotherapy efficacy.
Project description:Histone dimethyl transferase WHSC1 drives the transcription of MHC-I machinery in mouse and human colorectal cancer cells (CRCs); thus, WHSC1 downregulation potentiates CRCs to escape from cytotoxic CD8+ T cell responses. WHSC1 directly interacts with MHC-I transactivator, NLRC5 to selectively stimulate MHC-I gene expression. Thus, silencing Whsc1 diminished MHC-I level, impaired anti-tumor immunity and blunted immunotherapy efficacy.
Project description:There is increasing recognition of the prognostic significance of tumor cell major histocompatibility complex (MHC) class II expression in anti-cancer immunity. Relapse of acute myeloid leukemia (AML) following allogeneic stem cell transplantation (alloSCT) has recently been linked to MHC class II silencing in leukemic blasts; however, the regulation of MHC class II expression remains incompletely understood. Utilizing unbiased CRISPR-Cas9 screens, we identify that the C-terminal binding protein (CtBP) complex transcriptionally represses MHC class II pathway genes, while the E3 ubiquitin ligase complex component FBXO11 mediates degradation of CIITA, the principal transcription factor regulating MHC class II expression. Targeting these repressive mechanisms selectively induces MHC class II upregulation across a range of AML cell lines. Functionally, MHC class II+ leukemic blasts stimulate antigen-dependent CD4+ T cell activation and potent anti-tumor immune responses, providing fundamental insights into the graft-versus-leukemia effect. These findings establish the rationale for therapeutic strategies aimed at restoring tumor-specific MHC class II expression to salvage AML relapse post-alloSCT and also potentially to enhance immunotherapy outcomes in non-myeloid malignancies.
Project description:Immunotherapy efficacy is limited in melanoma, and combinations of immunotherapies with other modalities have yielded limited improvements but also adverse events requiring cessation of treatment. In addition to ineffective patient stratification, efficacy is impaired by paucity of intratumoral immune cells (itICs)—thus, effective strategies to safely increase itICs are needed. We report that dietary administration of L-fucose induces fucosylation and cell surface enrichment of the MHC-II protein HLA-DRB1 in melanoma cells, triggering CD4+T cell-mediated increases in ItICs and anti-tumor immunity, enhancing immune checkpoint blockade responses. Melanoma fucosylation and fucosylated HLA-DRB1 associate with intratumoral T cell abundance and anti-PD1 responder status in patient melanoma specimens, suggesting the potential use of melanoma fucosylation as a strategy for stratifying patients for immunotherapies. Our findings demonstrate that fucosylation is a key mediator of anti-tumor immunity, and importantly, suggest that L-fucose is a powerful agent for safely increasing ItICs and immunotherapy efficacy in melanoma.
Project description:Immunotherapy efficacy is limited in melanoma, and combinations of immunotherapies with other modalities have yielded limited improvements but also adverse events requiring cessation of treatment. In addition to ineffective patient stratification, efficacy is impaired by paucity of intratumoral immune cells (itICs)—thus, effective strategies to safely increase itICs are needed. We report that dietary administration of L-fucose induces fucosylation and cell surface enrichment of the MHC-II protein HLA-DRB1 in melanoma cells, triggering CD4+T cell-mediated increases in ItICs and anti-tumor immunity, enhancing immune checkpoint blockade responses. Melanoma fucosylation and fucosylated HLA-DRB1 associate with intratumoral T cell abundance and anti-PD1 responder status in patient melanoma specimens, suggesting the potential use of melanoma fucosylation as a strategy for stratifying patients for immunotherapies. Our findings demonstrate that fucosylation is a key mediator of anti-tumor immunity, and importantly, suggest that L-fucose is a powerful agent for safely increasing ItICs and immunotherapy efficacy in melanoma.
Project description:Immunotherapy efficacy is limited in melanoma, and combinations of immunotherapies with other modalities have yielded limited improvements but also adverse events requiring cessation of treatment. In addition to ineffective patient stratification, efficacy is impaired by paucity of intratumoral immune cells (itICs)—thus, effective strategies to safely increase itICs are needed. We report that dietary administration of L-fucose induces fucosylation and cell surface enrichment of the MHC-II protein HLA-DRB1 in melanoma cells, triggering CD4+T cell-mediated increases in ItICs and anti-tumor immunity, enhancing immune checkpoint blockade responses. Melanoma fucosylation and fucosylated HLA-DRB1 associate with intratumoral T cell abundance and anti-PD1 responder status in patient melanoma specimens, suggesting the potential use of melanoma fucosylation as a strategy for stratifying patients for immunotherapies. Our findings demonstrate that fucosylation is a key mediator of anti-tumor immunity, and importantly, suggest that L-fucose is a powerful agent for safely increasing ItICs and immunotherapy efficacy in melanoma.
Project description:Immunotherapy efficacy is limited in melanoma, and combinations of immunotherapies with other modalities have yielded limited improvements but also adverse events requiring cessation of treatment. In addition to ineffective patient stratification, efficacy is impaired by paucity of intratumoral immune cells (itICs)—thus, effective strategies to safely increase itICs are needed. We report that dietary administration of L-fucose induces fucosylation and cell surface enrichment of the MHC-II protein HLA-DRB1 in melanoma cells, triggering CD4+T cell-mediated increases in ItICs and anti-tumor immunity, enhancing immune checkpoint blockade responses. Melanoma fucosylation and fucosylated HLA-DRB1 associate with intratumoral T cell abundance and anti-PD1 responder status in patient melanoma specimens, suggesting the potential use of melanoma fucosylation as a strategy for stratifying patients for immunotherapies. Our findings demonstrate that fucosylation is a key mediator of anti-tumor immunity, and importantly, suggest that L-fucose is a powerful agent for safely increasing ItICs and immunotherapy efficacy in melanoma.