Intratumoral HPV16-Specific T Cells Constitute a Type I–Oriented Tumor Microenvironment to Improve Survival in HPV16-Driven Oropharyngeal Cancer

Abstract

Purpose: Human papillomavirus (HPV)-associated oropharyngeal squamous cell cancer (OPSCC) has a much better prognosis than HPV-negative OPSCC, and this is linked to dense tumor immune infiltration. As the viral antigens may trigger potent immunity, we studied the relationship between the presence of intratumoral HPV-specific T-cell responses, the immune contexture in the tumor microenvironment, and clinical outcome.Experimental Design: To this purpose, an in-depth analysis of tumor-infiltrating immune cells in a prospective cohort of 97 patients with HPV16-positive and HPV16-negative OPSCC was performed using functional T-cell assays, mass cytometry (CyTOF), flow cytometry, and fluorescent immunostaining of tumor tissues. Key findings were validated in a cohort of 75 patients with HPV16-positive OPSCC present in the publicly available The Cancer Genome Atlas database.Results: In 64% of the HPV16-positive tumors, type I HPV16-specific T cells were present. Their presence was not only strongly related to a better overall survival, a smaller tumor size, and less lymph node metastases but also to a type I-oriented tumor microenvironment, including high numbers of activated CD161 þ T cells, CD103 þ tissue-resident T cells, dendritic cells (DC), and DC-like macrophages. Conclusions:The viral antigens trigger a tumor-specific T-cell response that shapes a favorable immune contexture for the response to standard therapy. Hence, reinforcement of HPV16-specific T-cell reactivity is expected to boost this process. Clin Cancer Res; 24(3); 634-47. Ó2017 AACR.

NKG2A Blockade Potentiates CD8 T Cell Immunity Induced by Cancer Vaccines

“…Finally, HPV-negative HNSCC, which are generally less well infiltrated by T cells and which display a worse clinical outcome, did not show these immune gene correlations (Fig. S1C) (Ang et al, 2010, Welters et al, 2017). Together, these data suggested a potential negative role of the NKG2A/HLA-E axis via CD8 T cells and NK cells in HPV-induced head and neck cancer.…”

“…T-cell immune reactivity against the HPV16 oncoproteins E6 and E7 (HPV-IR) was assessed in short-term expanded tumor-infiltrating lymphocytes (Welters et al, 2017). Interestingly, HPV-negative tumors and HPV16-positive tumors lacking T cell immune reactivity to HPV antigens (HPV-IR - ) harboured much lower frequencies of NKG2A + CD8 T cells than HPV-induced carcinomas that did harbour HPV16-directed T cell reactivity (HPV-IR + ) (Fig.…”

“…Blood and tumor tissue samples were taken prior to treatment and handled as described previously (Welters et al, 2017). Peripheral blood mononuclear cells (PBMCs) and tumor infiltrating lymphocytes (TILs) were stored until use.…”

“…HPV typing was performed on former fixed paraffin embedded (FFPE) tumor sections at the department of pathology at the LUMC. HPV-specific immune reactivity of TILs was determined in a 5-day proliferation assay (Welters et al, 2017): HPV type 16 negative HNSCC (HPV-, n=5), HPV16-positive tumors without ex vivo immune reactivity (IR-, n=5) and HPV16-positive tumors displaying ex vivo immune reactivity to HPV16 (IR+, n=8). The phenotype and composition of dispersed OPSCC and expanded TILs was analysed by flow cytometry.…”

“…The phenotype of dispersed cervix carcinoma samples was analysed by high dimensional single cell time-of-flight mass cytometry (CyTOF) of 34 markers as described (Welters et al, 2017), with NKG2A- 142 Nd (Z199) replacing the CD34- 142 Nd antibody. Cluster analysis was performed independent from NKG2A expression and visualized in tSNE plots of pre-gated CD3 + CD8 T cells.…”