ABSTRACT: The cancer-immunity cycle requires cross-presenting type I conventional dendritic cells (cDC1s) that induce T cell-mediated immunity, but therapeutic strategies for enhancing intratumoral cDC1 function are currently inadequate. We found the epigenetic enzyme CARM1 (coactivator-associated arginine methyltransferase 1) to be a selective negative regulator of cancer antigen presentation by cDC1s but not cDC2s. Inactivation of the Carm1 gene promoted cDC1 antigen cross-presentation, activation, and accumulation in tumors, and a CARM1 inhibitor enhanced cDC1-mediated priming of T cells by means of a cancer neoantigen vaccine. CARM1 inhibition increased chromatin accessibility at BATF3-Jun and RelA sites that are critical for cDC1 function and activation. Transforming growth factor-β regulated Carm1 expression, which suggests that CARM1 inactivation enhanced intratumoral cDC1 function without altering cDC1 homeostasis. These studies identify CARM1 as a potential therapeutic target for enhancing the antitumor function of mouse and human cDC1s.
Author Info: (1) Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA. Department of Immunology, Harvard Medical School, Boston, MA, USA. (2) Department o

Author Info: (1) Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA. Department of Immunology, Harvard Medical School, Boston, MA, USA. (2) Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA. Broad Institute of Harvard and MIT, Cambridge, MA, USA. Systems, Synthetic, and Quantitative Biology Graduate Program, Harvard University, Cambridge, MA, USA. (3) Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA. (4) Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA. (5) Gene Lay Institute of Immunology and Inflammation, Brigham and Women's Hospital, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. (6) Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA. (7) Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA. (8) Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA. Department of Immunology, Harvard Medical School, Boston, MA, USA. (9) Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA. Department of Immunology, Harvard Medical School, Boston, MA, USA. (10) Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA. (11) Gene Lay Institute of Immunology and Inflammation, Brigham and Women's Hospital, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. (12) Molecular Imaging Core, Dana-Farber Cancer Institute, Boston, MA, USA. (13) Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA. Department of Immunology, Harvard Medical School, Boston, MA, USA. (14) Broad Institute of Harvard and MIT, Cambridge, MA, USA. Gene Lay Institute of Immunology and Inflammation, Brigham and Women's Hospital, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. (15) Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA. Tisch Cancer Institute, Black Family Stem Cell Institute, Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA. (16) Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA. Broad Institute of Harvard and MIT, Cambridge, MA, USA. Center for Cancer Genomics, Dana-Farber Cancer Institute, Boston, MA, USA. (17) Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA. (18) Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, USA. Department of Immunology, Harvard Medical School, Boston, MA, USA. Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA.
