Human papillomaviruses (HPVs) represent a large family of viral types associated with significant clinical disease of mucosal epithelium and oral and anogenital cancers. Increased evidences indicate that microbial imbalance may play a critical role in the development of multiple diseases, such as cancer, autoimmune conditions, and increased susceptibility to viral infection. However, to date few data are available on the complex interplay between persistent mucosal HPV infection, microbiota and cancer development. This project is focused on a comprehensive characterization of the role of oral and anogenital microenvironment in HPV driven cancer initiation and progression. Although HPV cancerogenesis has been thoroughly studied, its heterogeneous nature makes its understanding, prevention and proper treatment a remaining challenge in clinical settings. Through an integrative analysis of mucosal microbiota, HPV parameters (genotypes, E6/E7 mRNA expression and HPV genome integration), and type I/III interferon (IFN) signature, this pilot study will explore how microbiota mediate regulation of innate immune response in three different settings of HPV disease (oral, genital and anal), identifying predictive risk markers of precancerous mucosal lesions progression, and possibly therapeutic strategies to restore an healthy microenvironment. A clinical plus of the project is the focus on the HIV-1 risk group, men sex men (MSM), characterized by a high rate of HPV infection and anal cancer. Moreover, the IFN lambda production, which represents a key component of the mucosal immunity, has never been investigated in oral and anal HPV infection. This pilot study will provided first evidences on the functional implications of microbiota and host immune interactions in terms of risk assessment of HPV disease, opening new perspectives on the understanding of the potential effect of bacteria microbiota on IFN response, HPV persistence and cancerogenesis.
HPV are responsible for the development of almost all cervical cancers. HPV is also found in 95% of anal cancer and in 50% of penile, vulvar, and vaginal cancers, and they are increasingly found in a subset of head and neck cancers, i.e., oropharyngeal squamous cell carcinomas (OPSCC) (Gao et al., 2016). Increasing evidence indicates a key role for bacterial dysbiosis in driving carcinogenesis (Schwabe and Jobin C, 2013). Progressive growth of preneoplastic anal HPV lesions has been related to local and systemic immune dysregulation shaped by the microbiota profiles (Tummers B & Burg SH, 2015; Guimarães AG et al., 2015). However, in previous studies, there were no follow up, and the resolution of bacterial species was limited, therefore not allowing conclusive findings on the impact of bacterial species composition on the HPV related lesions. It has been also shown that by increasing IFN-related developmental regulator 1 (IFRD1)-expression, HPV impairs IFN production and immune cell attraction, contributing to immune evasion and HPV persistence (Tummers B et al., 2015). Of note, the IFN lambdas production, which represents a key component of the mucosal antiviral response, as well as the type I IFN signature, were not investigated (Lazear HM &Nice TJ 2015). In this context, the possibility to restore an healthy mucosal microenvironment through supplementation with probiotics is a new emerging area of interest (Mudd JC & Brenchley JM, 2016). A recent pilot study suggests that probiotics promote the clearance of HPV-related cervical abnormalities (Verhoeven V et al., 2013, our preliminary data), but no data are available for anal HPV infection. Since OPSCC incidence has increased in recent years, especially among younger women, there is also need to investigate microbiota-mediate alteration of host immune response (i.e. activation of type I/III IFNs response). Thus the project main goal is a comprehensive characterization of the role of mucosal microenvironment (microbiota and molecular type I and III IFN profiles) in HPV-driven cancer initiation and progression. Although HPV cancerogenesis has been thoroughly studied, its heterogeneous nature makes its understanding, prevention and proper treatment a remaining challenge in clinical settings. Through an integrative analysis of microbiota, HPV parameters (HPV genotype, integration status and E6/E7 mRNAs expression), and type I /III IFN transcriptome, this pilot study will explore for the first time to our knowledge the functional implications of host-microbiota interactions in HPV disease, identifying predictive risk markers of mucosal lesions progression, and possibly therapeutic strategies to restore an healthy mucosal microenvironment. A clinical plus of the project is that it will be entirely performed in vivo and focused on all type of HPV infection (genital, anal and oral). Moreover, the HIV risk group, MSM, characterized by a high rate of HPV infection and anal cancer will be included for the analysis of microbiota and IFN response. The following emerging questions will be addressed in HPV infected patients: i) Does a genital, anal or oral ¿disbiotic¿ profile related to HPV disease exist, and can it be used as predictive marker of high grade lesion development? ii) Which is the impact of virological parameters (HPV genotyping/integration) on HPV related lesions progression? iii) Is there a relationship between mucosal microbiota profile(s) and type I and III IFN response? iv) Can the type I/III IFN signatures affect the persistence of HPV infection? The feasibility of this pilot study is based on ad hoc multidisciplinary approach among clinicians from different departments of Sapienza University of Rome, virologists, and epidemiologist/statisticians. The specific expertise of each team, most of them collaborating here for the first time, will allow the development of new strong collaborations among the Sapienza¿s Departments, aiming at developing synergistic outcomes and opening future prospective in scientific interventions, on microbiome and HPV-cancer.