Project description:Histone H3 lysine (H3K4) methyltransferase KMT2D is a key regulator of gene expression, mainly through promoting H3K4 methylation and activating enhancers, and plays critical roles in development, differentiation, metabolism, and tumor suppression. Our study found that KMT2D-deficient HNSCC is sensitive to 2-DG plus DNA damage agents or 2-DG plus PAPR inhibitors in HNSCC mouse models and human cell lines. To further investigate the therapeutic potential of these treatments, we aimed to use patient-derived xenograft (PDX) with MT2D-inactivating utations. We sequenced one PDX from the University of Colorado School of Medicine by whole exome sequencing which has the nonsense mutation of KMT2D.
Project description:Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide, with 5-year survival of ~50%. Genomic profiling studies have identified important somatic mutations in this disease which presents an opportunity for precision medicine. We demonstrate that KMT2D, a histone methyltransferase harbors somatic mutations in ~17% of HNSCC and is associated with 2-year recurrence in TCGA data. Consistent with algorithmic prediction of bring a driver tumor-suppressor event, its loss results in larger oral tumors in immune-proficient orthotopic models. Mechanistically, we find that KMT2D knockdown or KMT2D mutation causes loss of H3K4me1-marked enhancers harboring IRF7/9 binding sites, which is known to regulate interferon signaling. Indeed, KMT2D loss in human and murine cell lines deregulated transcriptional levels of cytokine expression and impacted numerous immune signaling pathways, including interferon signaling. Consistently, Kmt2d knockdown in murine tumors exhibited decrease in IFN-producing effector T cells and an increase in T-cells with an exhausted phenotype. Epistasis experiments showed that exogenous treatment with IFNabrogated the increased tumor growth in Kmt2d-deficient oral tumors. Together, these results support the role of KMT2D as a tumor suppressor in HNSCC that regulates the tumor microenvironment by modulating H3K4me1-marked enhancers controlling interferon signaling.
Project description:Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide, with 5-year survival of ~50%. Genomic profiling studies have identified important somatic mutations in this disease which presents an opportunity for precision medicine. We demonstrate that KMT2D, a histone methyltransferase harbors somatic mutations in ~17% of HNSCC and is associated with 2-year recurrence in TCGA data. Consistent with algorithmic prediction of bring a driver tumor-suppressor event, its loss results in larger oral tumors in immune-proficient orthotopic models. Mechanistically, we find that KMT2D knockdown or KMT2D mutation causes loss of H3K4me1-marked enhancers harboring IRF7/9 binding sites, which is known to regulate interferon signaling. Indeed, KMT2D loss in human and murine cell lines deregulated transcriptional levels of cytokine expression and impacted numerous immune signaling pathways, including interferon signaling. Consistently, Kmt2d knockdown in murine tumors exhibited decrease in IFN-producing effector T cells and an increase in T-cells with an exhausted phenotype. Epistasis experiments showed that exogenous treatment with IFNabrogated the increased tumor growth in Kmt2d-deficient oral tumors. Together, these results support the role of KMT2D as a tumor suppressor in HNSCC that regulates the tumor microenvironment by modulating H3K4me1-marked enhancers controlling interferon signaling.
Project description:Histone H3 lysine (H3K4) methyltransferase KMT2D is a key regulator of gene expression, mainly through promoting H3K4 methylation and activating enhancers, and plays critical roles in development, differentiation, metabolism, and tumor suppression. To investigate the mechanisms by which KMT2D loss promotes HNSCC and to identify potential therapeutic targets, we generated KMT2D wild-type (KMT2D-WT) and KMT2D knock-out (KMT2D-KO) SCC23 HNSCC cells and performed RNA-seq under different glucose conditions.
Project description:Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide, with 5-year survival of ~50%. Genomic profiling studies have identified important somatic mutations in this disease which presents an opportunity for precision medicine. We demonstrate that KMT2D, a histone methyltransferase harbors somatic mutations in ~17% of HNSCC and is associated with 2-year recurrence in TCGA data. Consistent with algorithmic prediction of bring a driver tumor-suppressor event, its loss results in larger oral tumors in immune-proficient orthotopic models. Mechanistically, we find that KMT2D knockdown or KMT2D mutation causes loss of H3K4me1-marked enhancers harboring IRF7/9 binding sites, which is known to regulate interferon signaling. Indeed, KMT2D loss in human and murine cell lines deregulated transcriptional levels of cytokine expression and impacted numerous immune signaling pathways, including interferon signaling. Consistently, Kmt2d knockdown in murine tumors exhibited decrease in IFN-producing effector T cells and an increase in T-cells with an exhausted phenotype. Epistasis experiments showed that exogenous treatment with IFNabrogated the increased tumor growth in Kmt2d-deficient oral tumors. Together, these results support the role of KMT2D as a tumor suppressor in HNSCC that regulates the tumor microenvironment by modulating H3K4me1-marked enhancers controlling interferon signaling.