High infiltration of CD68+ macrophages is associated with poor prognoses of head and neck squamous cell carcinoma patients and is influenced by human papillomavirus

// Imelda Seminerio 1 , Nadege Kindt 1 , Geraldine Descamps 1 , Justine Bellier 1, 5 , Jerome R. Lechien 1 , Quentin Mat 1 , Charles Pottier 2 , Fabrice Journe 1, 3 and Sven Saussez 1, 4 1 Department of Human Anatomy and Experimental Oncology, Research Institute for Health Sciences and Technology, Faculty of Medicine and Pharmacy, University of Mons, Mons B-7000, Belgium 2 Department of Pathology, C.H.U., SART TILMAN, University of Liege, Liege 4000, Belgium 3 Laboratory of Oncology and Experimental Surgery, Jules Bordet Institute, Universite Libre de Bruxelles, Brussels 1000, Belgium 4 Department of Oto-Rhino-Laryngology, Faculty of Medicine, Universite Libre de Bruxelles (ULB), Brussels B-1000, Belgium 5 Present address: Metastasis Research Laboratory, GIGA-Cancer, University of Liege, Liege 4000, Belgium Correspondence to: Imelda Seminerio, email: imelda.seminerio@umons.ac.be Sven Saussez, email: sven.saussez@umons.ac.be Keywords: head and neck squamous cell carcinoma; human papillomavirus; CD68; macrophages; mouse Received: November 30, 2017      Accepted: January 19, 2018      Published: January 24, 2018 ABSTRACT Incidence of human papillomavirus (HPV)-related head and neck squamous cell carcinomas (HNSCCs) has increased over the last few decades. The reaction of the host immune system to these tumors remains biologically complex. Here, we investigated CD68+ macrophage numbers, reporting the prognostic value in comparison to other risk factors. We also examined CD68+ macrophage infiltration during disease progression regarding the impact of HPV infection, and we studied the role of HPV16-E6/E7 oncoproteins in CD68+ macrophage recruitment. CD68+ macrophage numbers were evaluated in 10 cases of tumor-free peri-tumoral epithelia, 43 cases of low-grade dysplasia, 45 cases of high-grade dysplasia and 110 cases of carcinoma. Our in vivo model was developed in 80 C3H/HeN mice orthotopically injected with HPV16-E6, -E7 or -E6/E7-transfected SCC-VII cell lines. High CD68+ macrophage numbers in the intra-tumoral compartment were associated with shorter patient survival (recurrence-free survival: p = 0.001; overall survival: p = 0.01). Multivariate analyses reported that CD68+ macrophage infiltration and tumor stage were strong and independent prognostic factors of HNSCC. CD68+ macrophage numbers increased during HNSCC progression both in intra-epithelial ( p < 0.001) and stromal compartments ( p < 0.001). A higher density of CD68+ macrophages was observed in advanced stages ( p = 0.004). Patients with transcriptionally active HPV infections had higher CD68+ macrophage density than did HPV-negative patients ( p = 0.003). CD68+ macrophage infiltration was higher in HPV-E7+ and −E6/E7+ mouse tumors than in -E6+ tumors ( p = 0.029 and p < 0.001). In conclusion, the extent of CD68+ macrophage infiltration is a significant prognostic factor for HNSCC patients. The recruitment of macrophages increases during disease progression and is influenced by the HPV virus.