{
  "abstract": "Background Human papillomavirus type 16 (HPV16) positive cancers have a tumor environment that induces antigen-presenting cells to increase IL-23 expression. Unclear is if HPV16 E6/E7 oncoproteins expressed in these cancers play a role in upregulating interleukin (IL)-23 in the tumor microenvironment (TME), and how this cytokine impacts the antitumor cytotoxic T-cell response in HPV16+ cancer.Methods CD8 T-cells targeting HPV16+ cancer cells were isolated from C57BL/6 mice bearing HPV16+ C3.43 tumors that were therapeutically vaccinated against HPV16 E6/E7 and incubated with IL-23. These T-cells were then co-incubated with HPV16+ target cells in a cytotoxicity assay to assess their cytolytic capacity. Additionally, carboxyfluorescein succinimidyl ester (CFSE) labeled T-cells were used to track the effect of IL-23 on their proliferation. The effect of IL-23 neutralization on vaccine-induced antitumor immunity during tumor progression was studied in vivo to assess its potential as either a standalone treatment or combined with a vaccine targeting HPV16 E6/E7. HPV16− tumors were engineered to express E6/E7 to find out if these oncoproteins upregulate IL-23. To understand how HPV oncoproteins in the TME affect transcriptional regulation of IL-23 producing cells, we used single-cell Assay for Transposase-Accessible Chromatin (ATAC)+RNA sequencing.Results Inside macrophages residing in the HPV+ TME, transcription factor enrichment and linkage analysis identified KLF2 as a potential regulator of Il23a. Overexpression of KLF2 in macrophages upregulates IL-23 production. CD8 T-cells that recognize HPV16+ cells incubated with IL-23 are inhibited in both their killing and proliferative capacities. IL-23 neutralization increased the presence of HPV-specific cytotoxic CD8 T-cells inside the HPV16+TME in an IL-17 independent manner. Combination of IL-23 neutralization followed by HPV16 E6/E7 vaccination increases survival by amplifying the anti-tumor immune response.Conclusion This study finds that the presence of HPV oncoproteins in tumor cells increases KLF2 expression in tumor-associated macrophages in vivo. It also shows that KLF2 upregulates IL-23 production in M2 macrophages, resulting in increased IL-23 levels in the TME. In addition, it is shown that elevated levels of IL-23 suppress the antitumor immune response and that IL-23 neutralization synergizes with therapeutic vaccination against HPV oncoproteins.",
  "authors": [
    {
      "affiliations": [
        "Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California, USA"
      ],
      "name": "Ruben Prins"
    },
    {
      "affiliations": [
        "Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California, USA"
      ],
      "name": "Daniel J Fernandez"
    },
    {
      "affiliations": [
        "Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California, USA",
        "USC Norris Comprehensive Cancer Center, Los Angeles, California, USA"
      ],
      "name": "Omid Akbari"
    },
    {
      "affiliations": [
        "USC Norris Comprehensive Cancer Center, Los Angeles, California, USA",
        "Obstetrics and Gynecology, University of Southern California, Los Angeles, California, USA"
      ],
      "name": "Diane M Da Silva"
    },
    {
      "affiliations": [
        "Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California, USA",
        "USC Norris Comprehensive Cancer Center, Los Angeles, California, USA",
        "Obstetrics and Gynecology, University of Southern California, Los Angeles, California, USA"
      ],
      "name": "W Martin Kast"
    }
  ],
  "title": "HPV16 E6 and E7 expressing cancer cells suppress the antitumor immune response by upregulating KLF2-mediated IL-23 expression in macrophages",
  "uid": "80446e41-2328-5e07-8c8c-4c9b51276046"
}