title: Cervical (pre)neoplastic microenvironment promotes the emergence of tolerogenic dendritic cells via RANKL secretion.
abstract: The progression of genital human papillomavirus (HPV) infections into preneoplastic lesions suggests that infected/malignant cells are not adequately recognized by the immune system. In this study, we demonstrated that cervical/vulvar cancer cells secrete factor(s) that affect both the maturation and function of dendritic cells (DC) leading to a tolerogenic profile. Indeed, DC cocultured with cancer cell lines display both a partially mature phenotype after lipopolysaccharide (LPS) maturation and an altered secretory profile (IL-10highand IL-12p70low). In addition, tumor-converted DC acquire the ability to alter T-cell proliferation and to induce FoxP3+suppressive T cells from naive CD4+T cells. Among the immunosuppressive factors implicated in DC alterations in genital (pre)neoplastic microenvironment, we identified receptor activator of nuclear factor kappa-B ligand (RANKL), a TNF family member, as a potential candidate. For the first time, we showed that RANKL expression strongly increases during cervical progression. We also confirmed that RANKL is directly secreted by cancer cells and this expression is not related to HPV viral oncoprotein induction. Interestingly, the addition of osteoprotegerin (OPG) in coculture experiments reduces significantly the inhibition of DC maturation, the release of a tolerogenic cytokine profile (IL-12lowIL-10high) and the induction of regulatory T (Treg) cells. Our findings suggest that the use of inhibitory molecules directed against RANKL in cervical/vulvar (pre)neoplastic lesions might prevent alterations of DC functionality and represent an attractive strategy to overcome immune tolerance in such cancers.
authors.affiliation: Laboratory of Experimental Pathology; GIGA-Cancer; University of Liège ; Liège, Belgium.
authors.forename: Stéphanie A
authors.initials: SA
authors.lastname: Demoulin
authors.affiliation: Department of Pathology; University Hospital of Liège ; Liège, Belgium.
authors.forename: Joan
authors.initials: J
authors.lastname: Somja
authors.affiliation: Laboratory of Experimental Pathology; GIGA-Cancer; University of Liège ; Liège, Belgium.
authors.forename: Anaëlle
authors.initials: A
authors.lastname: Duray
authors.affiliation: Laboratory of Experimental Pathology; GIGA-Cancer; University of Liège ; Liège, Belgium.
authors.forename: Samuel
authors.initials: S
authors.lastname: Guénin
authors.affiliation: Laboratory of Experimental Pathology; GIGA-Cancer; University of Liège ; Liège, Belgium.
authors.forename: Patrick
authors.initials: P
authors.lastname: Roncarati
authors.affiliation: Department of Pathology; University Hospital of Liège ; Liège, Belgium.
authors.forename: Philippe O
authors.initials: PO
authors.lastname: Delvenne
authors.affiliation: Laboratory of Experimental Pathology; GIGA-Cancer; University of Liège ; Liège, Belgium.
authors.forename: Michael F
authors.initials: MF
authors.lastname: Herfs
authors.affiliation: Laboratory of Experimental Pathology; GIGA-Cancer; University of Liège ; Liège, Belgium.
authors.forename: Pascale M
authors.initials: PM
authors.lastname: Hubert
keywords:  LC, Langerhans cells; LPS, lipopolysaccharide; APC, antigen presenting cells; DC, dendritic cells; GILZ, glucocorticoid-induced leucine zipper; HPV, human papillomavirus; HSIL, high grade intraepithelial lesions; IHC, immunohistochemistry; ILT3, Immunoglobulin-like transcript 3; KN, normal keratinocytes; LSIL, low grade intraepithelial lesion; MFI, mean fluorescence intensity; OPG, osteoprotegerin; PBMC, peripheral blood mononuclear cells; pDC, plasmacytoid dendritic cells; RANKL; RANKL, Receptor activator of nuclear factor kappa-B ligand; SCC, squamous cell carcinoma; SIL, squamous intraepithelial neoplasia; Treg cells; Treg cells, regulatory T cells; VIN, vulvar intraepithelial neoplasia; cervical cancers; dendritic cells; tolerogenicity