May 26, 2018
Source: Oral Oncol. 2018 Jul;82:75-82. doi: 10.1016/j.oraloncology.2018.05.010. Epub 2018 May 26.
Authors: K. Hladíková, S. Partlová, V. Koucký, J. Bouček, J.F. Fonteneau, M. Zábrodský, R. Tachezy, M. Grega, R. Špíšek, A. Fialová
Human papillomavirus (HPV) type 16 infection is one of the most important etiological agents of oropharyngeal squamous cell carcinoma. Patients with HPV-associated carcinomas of the head and neck were reported to have a better clinical outcome than patients with HPV-negative tumors. Because HPV16 E6 and E7 oncoproteins are highly immunogenic and constitutively expressed, HPV-specific T cell immunity may play the key role in improving the prognosis of these patients.
Tumor-derived T cells were expanded in high levels of IL-2 and stimulated with HPV16 E6/E7 peptides in the presence or absence of anti-PD-1 monoclonal antibody nivolumab and soluble Tim-3.
HPV16-specific tumor-infiltrating T cells were present in 73.1% of HPV-associated oropharyngeal tumors. HPV16 specific CD8+ TILs were able to produce IFNγ upon specific stimulation and predominantly expressed PD-1 but not Tim-3. Specific IFNγ production was further enhanced after a blockade of both PD-1 and Tim-3 pathways but not after a PD-1 blockade alone. Additionally, the specific stimulation of anti-HPV16 CD8+ T cells suppressed Tim-3 upregulation after the PD-1 blockade.
Our data provide the rationale for combination cancer immunotherapy approaches, including the dual blockade of PD-1 and Tim-3 and, potentially, the use of HPV16-directed therapeutic vaccines.