Spatial cellular order underlies locally-confined mechanisms of immune resistance in oropharyngeal cancer.

Abstract

Oropharyngeal squamous cell carcinomas (OPSCCs) frequently result from oncogenic human papilloma virus (HPV) infections (HPV-OPSCC). The mechanisms underlying effective immune escape, despite abundant viral antigens, are incompletely understood. Here, we performed single-cell spatial gene expression profiling of HPV-OPSCC to characterize cellular organization and mechanisms of immune resistance. We describe distinct tumor-parenchymal immune foci that differ in cytokine expression, spatial location, immune cell infiltration and cancer cell states. Furthermore, immune foci display profound differences related to co-inhibitory receptor signaling and immunosuppressive myeloid cells, suggesting that different tumor-parenchymal regions may be dominated by distinct, locally-confined mechanisms of immunosuppression. Additionally, senescent-like HPV-OPSCC cells lacking HPV transcripts (HPVoff) are evident across the tumor parenchyma and able to evade HPV-specific T cell-mediated immunity in vitro. HPVoff cells are enriched within hypoxic regions and near IFN-γ producing T cells suggesting that both hypoxia and IFN-γ signaling can promote the HPVoff phenotype. In conclusion, our findings highlight a complex cellular interplay underlying heterogeneous cancer cell states, spatial immune cell organization, and diverse mechanisms of immune escape.