Wang, Harris, and Dudgeon et al. identified the circadian rhythm gene Dec2 as a tumor-intrinsic regulator of dormancy and immune evasion in pancreatic cancer models. Dormant PDAC cells and occult disseminated tumor cells expressed high levels of Dec2, which repressed multiple components of the MHC-I antigen presentation pathway and reduced T cell-mediated cytotoxicity. Tumor surface MHC-I levels oscillated in antiphase to Dec2. Dec2 deletion restored antigen presentation, repolarized the PDAC TME from immune-cold to inflamed, and improved survival in immunocompetent (Ink4a.1 and 6419c5 models), but not immunodeficient mice.
Contributed by Shishir Pant
ABSTRACT: The mechanisms that regulate immune evasion by pancreatic ductal adenocarcinomas (PDACs) remain poorly understood. Using a mouse model of resectable PDAC, we identified an unknown role of the circadian rhythm gene Differentially Expressed in Chondrocytes 2 (Dec2) in regulating tumor progression and dormancy. Deletion of Dec2 from tumor cells substantially increased mouse survival after resection due to an immune-mediated mechanism, as the survival benefit was abrogated under immunodeficient conditions. Dec2 promotes immune evasion by repressing major histocompatibility complex class I (MHC-I)-dependent antigen presentation and by repolarizing the tumor microenvironment from immunologically cold (low T cell infiltration) to hot (elevated T cell infiltration). Dec2 is also a regulator of circadian rhythms, and we found that genes involved in MHC-I antigen presentation and MHC-I surface localization oscillated in a circadian manner, which was lost upon deletion of Dec2 in vitro. We conclude that Dec2 promotes primary PDAC progression and likely metastatic dormancy through immune evasion.
Author Info: (1) Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (2) Department of Surgery, Division of Surgical O
Author Info: (1) Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (2) Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (3) Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA. (4) Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (5) Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (6) Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (7) Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (8) Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (9) Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA. (10) Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA; Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, NY, USA. (11) Dewitt Daughtry Department of Surgery, Division of Surgical Oncology, University of Miami Miller School of Medicine, Miami, FL, USA. (12) Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA. (13) Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA. (14) Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, USA. (15) Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (16) Center for Cancer and Cell Biology, Van Andel Institute, Grand Rapids, MI, USA. (17) Center for Cancer and Cell Biology, Van Andel Institute, Grand Rapids, MI, USA. (18) Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, NY, USA; Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (19) Center for Advanced Research Technologies, University of Rochester Medical Center, Rochester, NY, USA. (20) Center for Cancer and Cell Biology, Van Andel Institute, Grand Rapids, MI, USA. (21) Center for Cancer and Cell Biology, Van Andel Institute, Grand Rapids, MI, USA. (22) Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (23) Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (24) Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (25) Dewitt Daughtry Department of Surgery, Division of Surgical Oncology, University of Miami Miller School of Medicine, Miami, FL, USA. (26) Dewitt Daughtry Department of Surgery, Division of Surgical Oncology, University of Miami Miller School of Medicine, Miami, FL, USA. (27) Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, NY, USA; Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. (28) Center for Cancer and Cell Biology, Van Andel Institute, Grand Rapids, MI, USA. (29) Department of Surgery, Division of Surgical Oncology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA; Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, NY, USA; Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA. Electronic address: darren_carpizo@urmc.rochester.edu.
