1. Neoantigen-Specific T Cells in a Novel Cutaneous Squamous Cell Carcinoma Model
- Author
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Katsanis, Emmanuel, Dickinson, Sally E., Hale, Taben M., Adams, Anngela Christina, Katsanis, Emmanuel, Dickinson, Sally E., Hale, Taben M., and Adams, Anngela Christina
- Abstract
Non-melanoma skin cancer, which includes cutaneous squamous cell carcinoma (cSCC), is the most common cancer. In the US, there are more than a million cases of cSCC diagnosed annually. Although most early stage cSCC are successfully treated with excision, cSCC results in significant morbidity, and approximately 4% of cSCC patients develop metastases and 2% die. Immune checkpoint inhibitors and other immunotherapies are becoming increasingly important in treating multiple cancer types, including cSCC, but only a fraction of patients respond. Yet, there is a paucity of clinically relevant cSCC murine models that can be used to study neoantigen-specific T cell responses. Outbred SKH-1 mice are highly susceptible to solar UV light-induced cSCC. However, an outbred strain limits the ability to evaluate MHC-restricted, antigen-specific T cell responses and perform studies with genetically engineered mice. To address this need, solar UV light was used to induce tumors in inbred FVB/N, BALB/c, and C57BL/6 mice. Solar UV light reliably induced tumors in FVB/N and BALB/c mice. In contrast, C57BL/6 mice were relatively resistant to tumor formation. Most tumors were histologically diagnosed as actinic keratosis, cSCC in situ, or invasive cSCC. Histologically confirmed solar UV-induced invasive cSCC tumors were used to create clonal cSCC cell lines on the BALB/c background. The cSCC cell lines recapitulate the high mutational burden, mutational profile, and driver mutations observed in human disease. These cSCC cell lines constitutively express MHC class I, and thus, can be targeted for destruction by CD8 T cells. T cells constrain the cSCC cell lines, as cSCC tumors grew faster in athymic mice, which lack mature T cells, compared to wild-type mice. In vivo depletion of CD8 and CD4 T cells demonstrated a major role for CD8 T cells and a supportive role for CD4 T cells in controlling cSCC growth. Vaccination with irradiated cSCC cells completely protected mice from tumor challeng
- Published
- 2024