Immune dysregulation and tumor-associated gene changes in recurrent respiratory papillomatosis: a paired microarray analysis

VEGF as a Key Actor in Recurrent Respiratory Papillomatosis: A Narrative Review

Recurrent respiratory papillomatosis (RRP) is a benign disease of the upper aerodigestive tract caused by human papillomavirus (HPV) types 6 and 11. The clinical course is unpredictable and some patients, especially younger children, experience a high rate of recurrence with a significant impact on their quality of life. The molecular mechanisms of HPV infection in keratinocytes have been extensively studied throughout the years, with particular regard to its role in causing malignant tumors, like cervical cancer and head and neck carcinomas. A minor but not negligible amount of the literature has investigated the molecular landscape of RRP patients, and some papers have studied the role of angiogenesis (the growth of blood vessels from pre-existing vasculature) in this disease. A central role in this process is played by vascular endothelial growth factor (VEGF), which activates different signaling cascades on multiple levels. The increased knowledge has led to the introduction of the VEGF inhibitor bevacizumab in recent years as an adjuvant treatment in some patients, with good results. This review summarizes the current evidence about the role of VEGF in the pathophysiology of RRP, the molecular pathways activated by binding with its receptors, and the current and future roles of anti-angiogenic treatment.

[Epidemiological features papillomatosis of the larynx in adults: a literature review]

The literature review presents current data on the epidemiology, drug, and surgical treatment of laryngeal papillomatosis in adults. Possible prospects for further study of the prevalence and incidence of the disease and provoking factors of recurrence of the disease for the development of possible preventive measures are considered.

The Efficacy of Human Papillomavirus Vaccination as an Adjuvant Therapy in Recurrent Respiratory Papillomatosis

OBJECTIVE

To characterize the efficacy of human papillomavirus (HPV) vaccination as an adjuvant therapy in recurrent respiratory papillomatosis (RRP).

DATA SOURCES

PubMed, Embase, Cochrane, Google Scholar, ClinicalTrials.gov, and Web of Science databases were queried for articles published before April 2021.

REVIEW METHODS

All retrieved studies (n = 870) were independently analyzed by two reviewers according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement using predefined inclusion and exclusion criteria. 13 studies met inclusion criteria. A random-effects meta-analysis was performed to study intersurgical interval (ISI) and number of surgical procedures per year before and after vaccination.

RESULTS

The systematic review included 13 studies, comprising 243 patients. All studies utilized the Gardasil® quadrivalent vaccine, and one study (Yiu et al. 2019) utilized both the quadrivalent and Gardasil® 9-valent vaccines. Our meta-analysis included 62 patients with ISI data across 4 studies, and 111 patients with data on the number of surgical procedures per month across 7 studies. The mean number of surgical procedures decreased by 4.43 per year after vaccination (95% CI, -7.48 to -1.37). Mean ISI increased after vaccination, with a mean difference of 15.73 months (95% CI, 1.46-29.99). Two studies reported on HPV sero-conversion, with HPV seropositivity of 100% prior to vaccination and 25.93% after vaccination.

CONCLUSION

The addition of HPV vaccination was associated with an increase in time between surgeries and reduction in the number of surgical procedures required. HPV vaccination may be a beneficial adjuvant treatment for RRP.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:2046-2054, 2023.

Involvement of TLR9 in priming the immune response in oral papillomatosis induced by low-risk HPV

Oral papillomatosis represents a benign lesion of the oral mucosa often induced by human papillomavirus (HPV) or having a non-infection local or general etiology. HPVs are very well adapted and efficient viruses able to produce changes in the immune system, endowed with the ability to replicate in the keratinocytes and to remain silent. The natural evolution of HPV infection is different, depending on the efficiency of the innate immune system. The purpose of this study was to explore Toll-like receptor 9 (TLR9) immunohistochemical expression in low-risk (LR)-HPV oral infection and its ability to facilitate an efficient immune response by activating the macrophages, which serve as main antigen-presenting cells. Samples of two groups of oral mucosae - LR-HPV-positive and HPV-negative - were processed for immunohistochemistry technique and incubated with antibody against TLR9 and cluster of differentiation 68 (CD68). Image analysis and morphometry were conducted to assess the intensity of TLR9 immune signal in the epithelium and the number of macrophages labeled by CD68. We found a statistically significant difference between macrophage count for the subjects in HPV-positive and HPV-negative groups; thought no significant differences of TLR9 immune signal was noted, which demonstrates a diminished immune response in HPV-positive group, probably influencing the time of lesion's clearance.

Molecular Mechanisms of Carcinogenesis in Pediatric Airways Tumors

Primary tumors of the airways in the pediatric population are very rare entities. For this reason, little is known about the pathogenesis of these neoplasms. Understanding the biology has different practical implications: for example, it could help in the differential diagnosis, have a prognostic significance, or may lead to the development of a targeted therapy. The aim of this article is to present the current knowledge about pediatric airways tumors, focusing on the molecular mechanisms that cause the onset and progression of these neoplasms. After a brief introduction of epidemiology and clinical presentation, the tumorigenesis of the most frequent pediatric airways tumors will be described: Juvenile-onset recurrent respiratory papillomatosis (JORRP), Subglottic Hemangiona (SH), Rhabdomyosarcoma (RMS), and Mucoepidermoid carcinoma (MEC).

[Recurrent laryngeal papillomatosis]

Human papillomaviruses (HPV) 6 and 11 cause 90% of recurrent laryngeal papillomatosis (RLP). It is unclear whether recurrences are caused by new infections or the spread of infected cells. Symptomatic and sometimes curative treatment is laser surgery or conventional microsurgical removal. RLP surgery aims to relieve shortness of breath and improve the voice. Patients (especially children) are affected by voice problems, repetitive surgeries, pulmonary manifestations, and psychological trauma. Vaccination with Gardasil 9 (Merck & Co., Rahway, NJ, USA) prevents new infections with HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58 and induces vaccine antigen-specific antibodies and CD4+ T helper cells. According to current studies, RLP can be avoided with prophylactic vaccination. The treatment is associated with a general vaccination risk (European Medicines Agency approval: girls and boys from 9 years). Studies also show that the vaccine after removal of HPV-associated neoplasia/papilloma prevents recurrences. Extension of the vaccination recommendation to prevent recurrences of HPV-associated diseases in men may promote applicability and herd immunity. For rare and treatment-refractory cases with laryngotracheal involvement, systemic therapy with bevacizumab (e.g. Avastin; Genentech, San Francisco, CA, USA), a VEGF antibody, is a promising adjuvant treatment option.

Role of chemokines in HPV-induced cancers

Human papillomaviruses (HPVs) cause cancers of the uterine cervix, oropharynx, anus, and vulvovaginal tract. Low-risk HPVs, such as HPV6 and 11, can also cause benign mucosal lesions including genital warts, and in patients with recurrent respiratory papillomatosis, lesions in the larynx, and on occasion, in the lungs. However, both high and less tumorigenic HPVs share a striking commonality in manipulating both innate and adaptive immune responses in HPV- infected keratinocytes, the natural host for HPV infection. In addition, immune/inflammatory cell infiltration into the tumor microenvironment influences cancer growth and prognosis, and this process is tightly regulated by different chemokines. Chemokines are small proteins and exert their biological effects by binding with G protein-coupled chemokine receptors (GPCRs) that are found on the surfaces of select target cells. Chemokines are not only involved in the establishment of a pro-tumorigenic microenvironment and organ-directed metastases but also involved in disease progression through enhancing tumor cell growth and proliferation. Therefore, having a solid grasp on chemokines and immune checkpoint modulators can help in the treatment of these cancers. In this review, we discuss the recent advances on the expression patterns and regulation of the main chemokines found in HPV-induced cancers, and their effects on both immune and non-immune cells in these lesions. Importantly, we also present the current knowledge of therapeutic interventions on the expression of specific chemokine and their receptors that have been shown to influence the development and progression of HPV-induced cancers.

Oropharyngeal tumor cells induce COX-2 expression in peripheral blood monocytes by secretion of IL-1α

Oropharyngeal squamous cell cancer (OPC) accounts for 3% of all cancers and greater than 1.5% of all cancer deaths in the United States, with marked treatment-associated morbidity in survivors. More than 80% of OPC is caused by HPV16. Tumors induced by HPV have been linked to impaired immune functions, with most studies focused on the local tumor microenvironment. Fewer studies have characterized the effects of these tumors on systemic responses in OPC, especially innate responses that drive subsequent adaptive responses, potentially creating feed-back loops favorable to the tumor. Here we report that elevated plasma levels of PGE2 are expressed in half of patients with OPC secondary to overexpression of COX-2 by peripheral blood monocytes, and this expression is driven by IL-1α secreted by the tumors. Monocytes from patients are much more sensitive to the stimulation than monocytes from controls, suggesting the possibility of enhanced immune-modulating feed-back loops. Furthermore, control monocytes pre-exposed to PGE2 overexpress COX-2 in response to IL-1α, simulating responses made by monocytes from some OPC patients. Disrupting the PGE2/IL-1α feed-back loop can have potential impact on targeted medical therapies.

Expanded Basal Compartment and Disrupted Barrier in Vocal Fold Epithelium Infected with Mouse Papillomavirus MmuPV1

Laryngeal infection with low-risk human papillomaviruses can cause recurrent respiratory papillomatosis (RRP), a disease with severe effects on vocal fold epithelium resulting in impaired voice function and communication. RRP research has been stymied by limited preclinical models. We recently reported a murine model of laryngeal MmuPV1 infection and disease in immunodeficient mice. In the current study, we compare quantitative and qualitative measures of epithelial proliferation, apoptosis, differentiation, and barrier between mice with MmuPV1-induced disease of the larynx and surrounding tissues and equal numbers of uninfected controls. Findings supported our hypothesis that laryngeal MmuPV1 infection recapitulates many features of RRP. Like RRP, MmuPV1 increased proliferation in infected vocal fold epithelium, expanded the basal compartment of cells, decreased differentiated cells, and altered cell–cell junctions and basement membrane. Effects of MmuPV1 on apoptosis were equivocal, as with RRP. Barrier markers resembled human neoplastic disease in severe MmuPV1-induced disease. We conclude that MmuPV1 infection of the mouse larynx provides a useful, if imperfect, preclinical model for RRP that will facilitate further study and treatment development for this intractable and devastating disease.

Reduced NK Cell Cytotoxicity by Papillomatosis-Derived TGF-β Contributing to Low-Risk HPV Persistence in JORRP Patients

The role of natural killer (NK) cells in juvenile-onset recurrent respiratory papillomatosis (JORRP) patients remains elusive. In this study, we find increased NK cell percentage, particularly CD11b-CD27- (DN) subsets in peripheral blood of JORRP patients and associated with disease activity. RNA sequencing shows a downregulated "natural killer cell-mediated cytotoxicity" feature in JORRP tumors. We also find impaired cytotoxic capacity and lower expression of NK cell-activating receptors including NKp30 and NKp46. Higher transforming growth factor-beta 1 (TGF-β1) is found both in plasma and tumor tissues of JORRP, and anti-TGF-β1 antibody could restore NK cell cytolytic activity and upregulate NKp30 and NKG2D expression. Also, we find a significantly higher Chemokine receptor type 6 (CXCR6) on NK cells in tumors compared with that in peripheral blood. Finally, RT-PCR analysis show that both HPV6-E6-E7 and HPV11-E6-E7 overexpression leads to higher TGFB1 expression compared with control SNU-1076 cell line, and higher CXCR6 expression is detected on NK coculture with HPV11-E6-E7-overexpressing cells. In conclusion, we demonstrate that TGF-β1 by papillomatosis leads to decreased NK cell cytotoxicity through downregulating NK cell-activating receptors in JORRP patients.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Hypopharynx, Larynx, Trachea and Parapharyngeal Space

In this article, we review the chapter on tumors of the larynx, hypopharynx, trachea and parapharyngeal space in the new edition of the WHO book, focusing on the new developments in comparison to the previous edition. Squamous cell carcinoma (SCC) and its variants are by far the most common malignancies at these locations, with very limited new insights. The most important is the introduction of new targeted treatment-checkpoint inhibitors, with a new task for pathologists, who may help to predict the response to treatment by analyzing the expression of targeted proteins in biopsy samples. Precancerous lesions remain a controversial topic and, similarly to other organs, it is acceptable to use the terms "dysplasia" or "squamous intraepithelial lesion" (SIL), but there is a slight difference between low-grade dysplasia and low-grade SIL: in the former, mild atypia must be present, while the latter also includes hyperplastic epithelium without atypia. Two approaches have been proposed: a two-tiered system with low- and high-grade dysplasia/SIL and a three-tiered system with an additional category, carcinoma in situ. We are still searching for reliable diagnostic markers to surpass the subjectivity in biopsy diagnosis, with a few potential candidate markers on the horizon, e.g., stem cell markers. Other tumors are rare at these locations, e.g., hematolymphoid, neuroendocrine and salivary gland neoplasms, and are no longer included in Chapter 3. They must be diagnosed according to criteria described in specific chapters. The same holds true for soft tissue tumors, with the exception of cartilaginous neoplasms, which are still included in Chapter 3.

A review of the risk factors associated with juvenile-onset recurrent respiratory papillomatosis: genetic, immune and clinical aspects

BACKGROUND

Juvenile-onset recurrent respiratory papillomatosis (JoRRP) is one of the most common benign lesions of hyperplastic respiratory epithelial tissue in children and is predominantly caused by human papillomaviruses (HPVs) 6 and 11. The clinical course of the disease is variable, and some patients even develop a malignancy. The purpose of this review was to summarize the related factors affecting the disease course in patients with JoRRP.

DATA SOURCES

We used databases, including PubMed and Google Scholar, to search for publications on factors associated with the genetic, immune, and clinical aspects of JoRRP. The most relevant articles to the scope of this review were chosen for analysis.

RESULTS

Mother-to-child transmission is the most important mode of disease transmission; other factors, such as immune condition or genetic susceptibility, may be important determinants of JoRRP occurrence. Genetically, the presence of DRB1*0301 and HPV 6/11 E6/E7 is associated with a more severe disease. Immunewise, patients have an enhanced T helper 2-like response. In addition, regulatory T cells are enriched in tumors and may become one of the effective prognostic indicators. For clinical characteristics, patients infected with HPV-11 have more aggressive disease. However, compared with HPV type, age at first onset is a more important factor related to the aggressiveness of JoRRP. Furthermore, socioeconomic status may also affect the course.

CONCLUSIONS

Genetic, immune, and some clinical factors have been noted to play an important role in the course of JoRRP. Exploring definite influencing factors will be an important direction of research in the future.

Comprehensive multiomic characterization of human papillomavirus-driven recurrent respiratory papillomatosis reveals distinct molecular subtypes

Recurrent respiratory papillomatosis (RRP) is a debilitating neoplastic disorder of the upper aerodigestive tract caused by chronic infection with low-risk human papillomavirus types 6 or 11. Patients with severe RRP can require hundreds of lifetime surgeries to control their disease and pulmonary papillomatosis can be fatal. Here we report the comprehensive genomic and transcriptomic characterization of respiratory papillomas. We discovered and characterized distinct subtypes with transcriptional resemblance to either a basal or differentiated cell state that associate with disease aggressiveness and differ in key molecular, immune and APOBEC mutagenesis profiles. Through integrated comparison with high-risk HPV-associated head and neck squamous cell carcinoma, our analysis revealed divergent molecular and immune papilloma subtypes that form independent of underlying genomic alterations. Cumulatively our results support the development of dysregulated cellular proliferation and suppressed anti-viral immunity through distinct programs of squamous cell differentiation and associated expression of low-risk HPV genes. These analyses provide insight into the pathogenesis of respiratory papillomas and provide a foundation for the development of therapeutic strategies.

Cem Sievers et al. performed genomic and transcriptomic analysis in human recurrent respiratory papillomatosis (RRP). They found that RRP harbors few genomic alterations, but that distinct transcriptional subtypes correlate with HPV gene expression and frequency of clinically-indicated interventions.

HPV and Recurrent Respiratory Papillomatosis: A Brief Review

Recurrent Respiratory Papillomatosis (RRP) is a rare but severe manifestation of human papillomavirus (HPV). As our knowledge about HPV infections has expanded, it has become possible to understand the course of RRP disease and unravel plausible efficient methods to manage the disease. However, the surge in reports on HPV has not been accompanied by a similar increase in research about RRP specifically. In this paper, we review the clinical manifestation and typical presentation of the illness. In addition, the pathogenesis and progression of the disease are described. On the other hand, we discuss the types of treatments currently available and future treatment strategies. The role of vaccination in both the prevention and treatment of RRP will also be reviewed. We believe this review is essential to update the general knowledge on RRP with the latest information available to date to enhance our understanding of RRP and its management.

Immune delineation of laryngeal papilloma reveals enhanced neutrophil associated gene profile

Laryngeal papilloma (LP) is a rare benign disease, caused by recurrent multisite papillomas that are referred to as recurrent respiratory papillomatosis (RRP). RRP is caused primarily by two types of human papillomavirus (HPV): HPV6 and HPV11. The immune dysregulation within the microenvironment of the lesions has been shown to likely play a role in the development of RRP. The present study aimed at analyzing the transcriptional profile of immune response genes and cancer-related genes in the LP microenvironment. We used the NanoString^® nCounter^® analysis system to study expression of 730 genes among seven paired samples of LP and healthy laryngeal (HL) tissue. qRT-PCR and flow cytometric analysis was performed to confirm identified transcripts and follow-up scores of infiltrating immune cells, respectively. In total, 113 differentially expressed transcripts were detected of which 37 showed increased expression levels and 76 decreased expression levels in the LP samples compared to the HL samples (fold change ≥ 2). Transcripts with increased expression levels included S100As (A7, A8, and A12), CEACAM1, neutrophil activation associated cytokines (IL8), chemokines (CXCL6), and IL receptors, e.g., IL4R. Transcripts with decreased expression in LP were associated with innate and adaptive immunity. Overall, HPV6 and 11 were present in 67% and 33% of the patients, respectively. There was a significant increase in neutrophils and a significant decrease in CD8⁺ T cells in LP. LP samples display an immune profile characterized by enhanced expression of neutrophilic markers and significantly reduced T cell-associated markers.

Effect of E2 and long control region polymorphisms on disease severity in human papillomavirus type 11 mediated mucosal disease: Protein modelling and functional analysis

Interaction of the long control region (LCR) and the E2 protein of HPV11s was studied by in silico modelling and in vitro functional analysis. Genomes of HPV11s from fifteen (six known and nine novel) patients (two solitary papillomas, eleven respiratory papillomatoses of different severity, one condyloma acuminatum and one cervical atypia) were sequenced; E2 polymorphisms were analysed in silico by protein modelling. E2 and LCR variants were cloned into pcDNA3.1+ expression vector and into pALuc reporter vector, respectively, transfected to HEp2 cells alone or in different combinations and the luciferase activity was measured. In the E2, the ubiquitous polymorphism K308R caused stronger binding between the dimers but did not alter DNA binding; E2s with this polymorphism were significantly less efficient than the reference in promoting LCR activity. The unique polymorphism Q86K changed the negative surface charge of E2 (Q86) to positive (K86). The unique polymorphisms S245F and N247T in the hinge region disrupt a probable phosphorylation site in a RXXS motif targeted by protein kinase A and B, but do not affect directly the amino acids critical to nuclear transport. Both unique patterns partly restored the LCR activating potential disrupted by K308R. A unique E2/E4 ORF with a 58-bp deletion leading to a frameshift and an early stop codon resulted in a practically nonfunctional E2, and was associated with a papillomatosis with dysplasia. When testing existing LCR-E2 combinations, LCR with intrinsically lower enhancer capacity was only marginally activated by its E2 (R308 and the deletion mutant), and did not significantly exceed the activity of the reference LCR without E2. Combined with more potent LCRs associated with more severe disease, the activity was significantly higher, but still significantly lower than LCRs with reference E2. In summary, LCR-E2 interaction determined by their polymorphisms may explain, at least partly, differences in disease severity.

A novel cancer preventative botanical mixture, TriCurin, inhibits viral transcripts and the growth of W12 cervical cells harbouring extrachromosomal or integrated HPV16 DNA

BACKGROUND

The phytochemical mixture TriCurin (curcumin, epigallocatechin gallate (EGCG) and resveratrol) eliminates human papillomavirus (HPV) (+) cancer cells in vitro and in vivo. In this study, we further evaluate TriCurin.

METHODS

The activity of TriCurin and its individual compounds was assayed on W12 cells, derived from a cervical precancer containing episomal and integrated HPV16 DNA, using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays, microscopy and reverse transcription-polymerase chain reaction (RT-PCR), and on HeLa cells by gene expression analysis. The stability and toxicity of TriCurin microemulsion were tested in an organotypic cervical tissue model.

RESULTS

TriCurin and its individual compounds inhibit the growth of W12 cells, episomal, type 1 and 2 integrants; the relative order of activity is TriCurin, EGCG, curcumin, or resveratrol. RT-PCR shows that TriCurin activates p53 and suppresses HPV16 mRNAs E1, E2, E4, E6 and E7 at 24 h in W12 cells. Gene expression analysis shows that TriCurin activates pro-apoptotic genes and represses anti-apoptotic genes in HeLa cells. TriCurin in a microemulsion is stable and non-toxic to cervical tissue. The combination of TriCurin and tanshinone IIA exhibits additional synergy against HeLa cells.

CONCLUSIONS

TriCurin, and the combination of TriCurin with tanshinone IIA, are effective against HPV (+) cells. The phytochemical mixture, in the microemulsion-based cream, is a promising therapeutic for the prevention and treatment of cervical cancer.

P16 detection in benign, precursor epithelial lesions and carcinomas of head and neck

BACKGROUND

Human papillomavirus (HPV) had recently been implicated in the pathogenesis of Head and Neck SCCs. The biological role of HPV in benign and pre-cancerous lesions is far less studied. p16 is a widely accepted marker to detect immonohistochemically the presence of HPV.

METHODS

We evaluated, immunohistochemically, expression of p16 in 212 specimens: glottis, supraglottis, oropharynx, nasal/paranasal, with various diagnoses: hyperplasia, polyp/nodule, keratosis, papilloma, inverted papilloma, dysplasia, cancer (SCC). Analysis was completed according to location and disease.

RESULTS

Hyperplasias/polyps were all negative for p16. A small percentage of papillomas was p16+ regardless of their location (12.5 %), the majority of inverted papillomas were p16+ (78.6 %) and statistically significant (p < 0.04). In carcinomas, 18/59 were p16+ (30.5 %): nasal/paranasal SCCs had a significantly higher percentage of p16+ cancer cells compared to glottis (p = 0.009), while tumours of the supraglottis/oropharynx had an intermediate score for p16+ cells (p = 0.07). Dysplasias were p16+ in 9/64 (14 %) regardless of grading (p = 0.03 compared to carcinomas).

CONCLUSION

p16 was highly detected in inverted papillomas and in certain anatomic sites; however, it failed to be traced in benign lesions and only rarely encountered in dysplasias.

Altered Monocyte and Langerhans Cell Innate Immunity in Patients With Recurrent Respiratory Papillomatosis (RRP)

The micromilieu within respiratory papillomas supports persistent human papillomavirus (HPV) infection and disease recurrence in patients with recurrent respiratory papillomatosis (RRP). These patients show polarized (T_H2-/Treg) adaptive immunity in papillomas and blood, enriched immature Langerhans cell (iLC) numbers, and overexpression of cyclooxygenase-2/prostaglandin E₂ (PGE₂) in the upper airway. Blood monocyte-derived, and tissue-derived iLCs from RRP patients and controls were now studied to more fully understand innate immune dysregulation in RRP. Patients' monocytes generated fewer iLCs than controls, due to a reduced fraction of classical monocytes that generated most but not all the iLCs. Prostaglandin E₂, which was elevated in RRP plasma, reduced monocyte-iLC differentiation from controls to the levels of RRP patients, but had no effect on subsequent iLC maturation. Cytokine/chemokine responses by iLCs from papillomas, foreskin, and abdominal skin differed significantly. Freshly derived tissue iLCs expressed low CCL-1 and high CCL-20 mRNAs and were unresponsive to IL-36γ stimulation. Papilloma iLCs uniquely expressed IL-36γ at baseline and expressed CCL1 when cultured overnight outside their immunosuppressive microenvironment without additional stimulation. We conclude that monocyte/iLC innate immunity is impaired in RRP, in part due to increased PGE₂ exposure in vivo. The immunosuppressive papilloma microenvironment likely alters iLC responses, and vice versa, supporting T_H2-like/Treg HPV-specific adaptive immunity in RRP.

Relationship between inflammation and the severity of Recurrent Respiratory Papillomatosis

OBJECTIVE

To characterize inflammatory cells in Recurrent Respiratory Papillomatosis (RRP) and to correlate it with severity using the Derkay laryngoscopic scale.

MATERIALS AND METHODS

The data and biopsies from 36 patients with Juvenile (JRRP) and 56 patients with Adult (ARRP) were collected and analyzed under light microscopy. The patients were separated into groups according to the Derkay index: ≥20 for the most severe and < 20 for the less severe cases. Immunohistochemical analysis using CD3, CD4, CD8, CD15, CD20, CD68, FoxP3 and MUM-1 antibodies was performed, and the inflammatory cells were quantified. All the clinicopathological characteristics and the results of the immunohistochemical analysis were compared among the groups proposed using the Chi-Square test and correlated through the Spearman correlation test.

RESULTS

The ARRP showed significantly higher quantities of CD3+, CD8+ and MUM1+ cells (p < .05) than the JRRP samples. The presence of CD15+ cells showed positive correlation with the Derkay index (p < .05), while the MUM-1+ cells showed an inverse correlation (p = .01).

CONCLUSION

There are differences between the inflammatory cells population in the juvenile and adult groups and it can be related to disease severity.

Immunological tolerance of low-risk HPV in recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is characterized by benign exophytic lesions of the respiratory tract caused by the human papillomavirus (HPV), in particular low-risk HPV6 and HPV11. Aggressiveness varies greatly among patients. Surgical excision is the current standard of care for RRP, with adjuvant therapy used when surgery cannot control disease recurrence. Numerous adjuvant therapies have been used to control RRP with some success, but none are curative. Current literature supports a polarization of the adaptive immune response to a T helper type 2 (Th2)-like or T regulatory phenotype, driven by a complex interplay between innate immunity, adaptive immunity and HPV6/11 proteins. Additionally, certain immunogenetic polymorphisms can predispose individuals to an HPV6/11-tolerant microenvironment. As a result, immunomodulatory efforts are being made to restore the host immune system to a more balanced T cell phenotype and clear viral infection. Literature has shown exciting evidence for the role of HPV vaccination with Gardasil or Gardasil-9 as both primary prevention, by decreasing incidence through childhood vaccinations, and secondary prevention, by treating active RRP disease. Multi-institution randomized clinical trials are needed to better assess their efficacy as treatment for active disease. Interestingly, a DNA vaccine has recently shown in-vitro success in generating a more robust CD8⁺ T cell response. Furthermore, clinical trials for programmed death 1 (PD-1) inhibitors are under investigation for RRP management. Molecular insights into RRP, in particular the interplay between RRP and the immune system, are needed to advance our understanding of this disease and may lead to the identification of immunomodulatory agents to better manage RRP.

Clinical Activity of Nivolumab for Human Papilloma Virus-Related Juvenile-Onset Recurrent Respiratory Papillomatosis

BACKGROUND

Juvenile-onset recurrent respiratory papillomatosis (JO-RRP) is a human papilloma virus-mediated progressive benign neoplasm that affects children and young adults. Primary management consists of regular surgical debulking to maintain airway patency and vocal function. Like condyloma acuminata, JO-RRP is associated with immune dysregulation, and T cells isolated from papillomas express an anergic phenotype. Therefore, we hypothesized that programmed death protein 1 axis inhibition could stabilize tumor growth.

MATERIALS AND METHODS

We treated two patients with refractory JO-RRP using nivolumab, with the primary objective of assessing clinical activity. We explored baseline papilloma features using immunohistochemistry and comprehensive genomic profiling.

RESULTS

Both patients experienced symptomatic improvement, and interval laryngoscopies revealed a reduction in papillomatosis burden. One patient has not required subsequent surgical debridement for almost 2 years. On pathologic examination of pretreatment papillomas from both cases, infiltrating T cells were evident in the papilloma stroma, and papilloma programmed death ligand 1 expression was absent. Papilloma mutational load ranged between three and six mutations per megabase for each case. From on-treatment biopsy tissue, a higher amount of intraepithelial T cells and programmed death ligand 1 expression were detected in the papilloma.

CONCLUSION

Nivolumab appears to have promising activity in JO-RRP, and further clinical investigation with more patients in clinical trials is warranted.

IMPLICATIONS FOR PRACTICE

To the authors' knowledge, this article is the first report describing clinical activity with a programed cell death-1 (PD-1) inhibitor to treat a rare but detrimental type of respiratory tract epithelial neoplasm that afflicts young adults. Two patients were treated, and tumor features, such as mutational load, were examined with the intent to stimulate future hypotheses for translational research. The safety and activity of PD-1 inhibitors in this population still need to be corroborated in clinical trials and should not yet be adopted into clinical practice.

Microarray analysis of human keratinocytes from different anatomic sites reveals site-specific immune signaling and responses to human papillomavirus type 16 transfection

BACKGROUND

Stratified human keratinocytes (SHKs) are an essential part of mucosal innate immune response that modulates adaptive immunity to microbes encountered in the environment. The importance of these SHKs in mucosal integrity and development has been well characterized, however their regulatory immunologic role at different mucosal sites, has not. In this study we compared the immune gene expression of SHKs from five different anatomical sites before and after HPV16 transfection using microarray analyses.

METHODS

Individual pools of human keratinocytes from foreskin, cervix, vagina, gingiva, and tonsils (HFKs, HCKs, HVKs, HGKs and HTLKs) were prepared. Organotypic (raft) cultures were established for both normal and HPV16 immortalized HFKs, HCKs, HVKs, HGKs and HTLKs lines which stably maintained episomal HPV16 DNA. Microarray analysis was carried out using the HumanHT-12 V4 gene chip (Illumina). Immune gene expression profiles were obtained by global gene chip (GeneSifter) and Ingenuity pathway analysis (IPA) for each individual site, with or without HPV16 transfection.

RESULTS

We examined site specific innate immune response gene expression in SHKs from all five different anatomical sites before and after HPV16 transfection. We observed marked differences in SHK immune gene repertoires within and between mucosal tracts before HPV 16 infection. In addition, we observed additional changes in SHKs immune gene repertoire patterns when these SHKs were productively transfected with HPV16. Some immune response genes were similarly expressed by SHKs from different sites. However, there was also variable expression of non-immune response genes, such as keratin genes, by the different SHKs.

CONCLUSIONS

Our results suggest that keratinocytes from different anatomical sites are likely hard wired in their innate immune responses, and that these immune responses are unique depending on the anatomical site from which the SHKs were derived. These observations may help explain why select HPV types predominate at different mucosal sites, cause persistent infection at these sites, and on occasion, lead to HPV induced malignant and benign tumor development.

Current and future management of recurrent respiratory papillomatosis

Objectives

Recurrent respiratory papillomatosis (RRP) is a chronic disease of the respiratory tract that occurs in both children and adults. It is caused by the human papillomavirus (HPV), in particular low‐risk HPV6 and HPV11, and aggressiveness varies among patients. RRP remains a chronic disease that is difficult to manage. This review provides perspectives on current and future management of RRP.

Results

The current standard of care is surgical excision, with adjuvant therapies as needed. Surgical management of RRP has evolved with the introduction of microdebriders and photoangiolytic lasers; the latter can now be used in the office setting. Numerous adjuvant pharmacologic therapies have been utilized with some success. Also, exciting preliminary data show that HPV vaccines may prolong the time to recurrence in the RRP population. There is also optimism that wide‐spread HPV vaccination could reduce RRP incidence indirectly by preventing vertical HPV transmission to newborns.

Conclusion

To date, the biology of RRP is not well understood, although it has been noted to become more aggressive in the setting of immune suppression. Additional research is needed to better understand immune system dysfunction in RRP such that immunomodulatory approaches may be developed for RRP management.

Level of Evidence

4

Interferon-γ Treatment of Human Laryngotracheal Stenosis-Derived Fibroblasts

Importance

Laryngotracheal stenosis (LTS) is a fibroproliferative disorder of the glottis, subglottis, and trachea. In models of fibrosis from other organ systems, the CD4+ T-cell response has been shown to regulate extracellular matrix deposition. Specifically, helper T cell 2 (TH2) promotes fibrosis, whereas TH1 and associated cytokines have been shown to be antifibrotic. However, this antifibrotic effect of the TH1 response has not been demonstrated in LTS.

Objective

To determine whether the TH1 cytokine interferon-γ inhibits the function of LTS-derived fibroblasts in vitro.

Design, Setting, and Participants

This in vitro controlled study included 6 patients with iatrogenic LTS undergoing routine surgical subglottic and tracheal dilation at a single institution. Fibroblasts were isolated from biopsy specimens of laryngotracheal scar and normal-appearing trachea. The presence of fibroblasts was confirmed by an immunohistochemical analysis. Laryngotracheal stenosis-derived fibroblasts were treated with interferon-γ and compared with untreated controls (2 sets of untreated, LTS-derived fibroblasts [media did not contain interferon-γ]) and normal airway fibroblasts (fibroblasts isolated from normal trachea). Data were collected from August 2015 through June 2016.

Interventions

Treatment with interferon-γ, 10 ng/mL.

Main Outcomes and Measures

Cellular proliferation, fibrosis gene expression (using quantitative reverse transcription polymerase chain reaction analysis), soluble collagen, and cellular histologic features were assessed.

Results

Among the 6 patients (6 women; mean [SD] age, 38.3 [17.2] years), LTS-derived fibroblast proliferation was reduced in patients who received interferon-γ treatment compared with untreated controls on days 3 (mean difference, -6515 cells; 95% CI, -10 630 to -2600 cells) to 6 (mean difference, -47 521 cells; 95% CI, -81 285 to -13 757 cells). Interferon-γ treatment reduced collagen types I and III gene expression by 86% and 68%, respectively, and resulted in lower total collagen production (10.94 vs 14.89 μg/mL). In addition, interferon-γ treatment resulted in a 32% reduction in expression of transforming growth factor β in LTS-derived fibroblasts.

Conclusions and Relevance

Interferon-γ reduced proliferation, soluble collagen production, and collagen expression in LTS-derived fibroblasts while also reducing the expression of the profibrotic cytokine transforming growth factor β. These findings suggest that therapeutics aimed at increasing interferon-γ and the TH1 response could attenuate LTS.

IL-36 induces cytokine IL-6 and chemokine CXCL8 expression in human lung tissue cells: Implications for pulmonary inflammatory responses

IL-36α, IL-36β and IL-36γ are cytokine members of IL-1 family. Although IL-36 expression was observed in human lung during pulmonary infections, it remains unknown whether IL-36 could act directly on lung tissue cells during pulmonary inflammatory responses. In this study, we showed that IL-36 receptor was expressed in human lung fibroblasts and bronchial epithelial cells. Correspondingly, IL-36α, IL-36β or IL-36γ up-regulated gene expression of cytokine IL-6 and chemokine CXCL8 in human lung fibroblasts and bronchial epithelial cells, and promoted IL-6 and CXCL8 release from human lung fibroblasts and bronchial epithelial cells. The production of IL-6 and CXCL8 in these lung tissues cells induced by IL-36α, IL-36β or IL-36γ was regulated by p38MAPK, ERK or Akt signaling pathways. Taken together, the above results suggest that IL-36-mediated IL-6 and CXCL8 production in human lung fibroblasts and bronchial epithelial cells may be involved in pulmonary inflammation especially caused by bacterial or viral infections.

Lymphocyte profile and cytokine mRNA expression in peripheral blood mononuclear cells of patients with recurrent respiratory papillomatosis suggest dysregulated cytokine mRNA response and impaired cytotoxic capacity

Objectives

Recurrent respiratory papillomatosis (RRP) is a relatively rare, chronic disease caused by Human Papilloma Virus (HPV) 6 and 11, and characterized by wart‐like lesions in the airway affecting voice and respiratory function. The majority of HPV infections are asymptomatic and resolve spontaneously, however, some individuals are afflicted with persistent HPV infections. Failure to eliminate HPV 6 and 11 due to a defect immune responsiveness to these specific genotypes is proposed to play a major role in the development of RRP.

Methods

We performed a phenotypic characterization of peripheral blood mononuclear cells (PBMC) collected from 16 RRP patients and 12 age‐matched healthy controls, using immunoflow cytometry, and monoclonal antibodies against differentiation and activation markers. The cytokine mRNA profile of monocytes, T helper‐, T cytotoxic‐, and NK cells was assessed using RT‐qPCR cytokine analysis, differentiating between Th1‐, Th2‐, Th3/regulatory‐, and inflammatory immune responses.

Results

We found a dominance of cytotoxic T cells, activated NK cells, and high numbers of stressed MIC A/B expressing lymphocytes. There was an overall suppression of cytokine mRNA production and an aberrant cytokine mRNA profile in the activated NK cells.

Conclusion

These findings demonstrate an immune dysregulation with inverted CD4⁺/CD8⁺ ratio and aberrant cytokine mRNA production in RRP patients, compared to healthy controls.

Poly(I:C) induces controlled release of IL-36γ from keratinocytes in the absence of cell death

The epithelium is part of an integrated immune system where cytokines, toll-like receptors and their ligands, and extracellular vesicles play a crucial role in initiating an innate immune response. IL-36γ is a pro-inflammatory member of the IL-1 family that is mainly expressed by epithelial cells, but regulation of its expression and release are only beginning to be understood. Previous studies reported that IL-36γ is abundant in recurrent respiratory papillomatosis, a rare but devastating disease caused by human papillomaviruses (HPV) types 6 and 11, in which papillomas recurrently grow in and block the airway. Despite the overexpression of IL-36γ, papilloma tissues show no evidence of inflammation, possibly due to suppression of its release by HPVs. We have used primary human foreskin keratinocytes as a model to study IL-36γ regulation in normal epithelial cells. Low doses of poly(I:C) mediate expression and release of IL-36γ without inducing the cell death reported by those using high doses. PKR, an enzyme required for inflammasome activation, does not contribute to controlled release of IL36γ. The keratinocytes secrete IL-36γ in two forms, soluble and in extracellular vesicles. We conclude that there are two separately regulated pathways for the controlled secretion of IL-36γ from keratinocytes, which could contribute to the modulation of both local and systemic immune responses to viruses and other pathogens.

The IL-1 cytokine family and its role in inflammation and fibrosis in the lung

The IL-1 cytokine family comprises 11 members (7 ligands with agonist activity, 3 receptor antagonists and 1 anti-inflammatory cytokine) and is recognised as a key mediator of inflammation and fibrosis in multiple tissues including the lung. IL-1 targeted therapies have been successfully employed to treat a range of inflammatory conditions such as rheumatoid arthritis and gouty arthritis. This review will introduce the members of the IL-1 cytokine family, briefly discuss the cellular origins and cellular targets and provide an overview of the role of these molecules in inflammation and fibrosis in the lung.

Identification of key target genes and pathways in laryngeal carcinoma

The purpose of the present study was to screen the key genes associated with laryngeal carcinoma and to investigate the molecular mechanism of laryngeal carcinoma progression. The gene expression profile of GSE10935 [Gene Expression Omnibus (GEO) accession number], including 12 specimens from laryngeal papillomas and 12 specimens from normal laryngeal epithelia controls, was downloaded from the GEO database. Differentially expressed genes (DEGs) were screened in laryngeal papillomas compared with normal controls using Limma package in R language, followed by Gene Ontology (GO) enrichment analysis and pathway enrichment analysis. Furthermore, the protein-protein interaction (PPI) network of DEGs was constructed using Cytoscape software and modules were analyzed using MCODE plugin from the PPI network. Furthermore, significant biological pathway regions (sub-pathway) were identified by using iSubpathwayMiner analysis. A total of 67 DEGs were identified, including 27 up-regulated genes and 40 down-regulated genes and they were involved in different GO terms and pathways. PPI network analysis revealed that Ras association (RalGDS/AF-6) domain family member 1 (RASSF1) was a hub protein. The sub-pathway analysis identified 9 significantly enriched sub-pathways, including glycolysis/gluconeogenesis and nitrogen metabolism. Genes such as phosphoglycerate kinase 1 (PGK1), carbonic anhydrase II (CA2), and carbonic anhydrase XII (CA12) whose node degrees were >10 were identified in the disease risk sub-pathway. Genes in the sub-pathway, such as RASSF1, PGK1, CA2 and CA12 were presumed to serve critical roles in laryngeal carcinoma. The present study identified DEGs and their sub-pathways in the disease, which may serve as potential targets for treatment of laryngeal carcinoma.

Immune Dysregulation in Patients Persistently Infected with Human Papillomaviruses 6 and 11

Human Papillomaviruses (HPVs) 6 and 11 are part of a large family of small DNA viruses, some of which are commensal. Although much of the population can contain or clear infection with these viruses, there is a subset of individuals who develop persistent infection that can cause significant morbidity and on occasion mortality. Depending on the site of infection, patients chronically infected with these viruses develop either recurrent, and on occasion, severe genital warts or recurrent respiratory papillomas that can obstruct the upper airway. The HPV-induced diseases described are likely the result of a complex and localized immune suppressive milieu that is characteristic of patients with persistent HPV infection. We review data that documents impaired Langerhans cell responses and maturation, describes the polarized adaptive T-cell immune responses made to these viruses, and the expression of class select II MHC and KIR genes that associate with severe HPV6 and 11 induced disease. Finally, we review evidence that documents the polarization of functional T_H2 and T-regulatory T-cells in tissues persistently infected with HPV6 and 11, and we review evidence that there is suppression of natural killer cell function. Together, these altered innate and adaptive immune responses contribute to the cellular and humoral microenvironment that supports HPV 6 and 11-induced disease.

Decreased Langerhans cell responses to IL-36γ: altered innate immunity in patients with recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is a rare, chronic disease caused by human papillomaviruses (HPVs) types 6 and 11 that is characterized by the polarization of adaptive immune responses that support persistent HPV infection. Respiratory papillomas express elevated mRNA levels of IL-36γ, a proinflammatory cytokine in comparison to autologous clinically normal laryngeal tissues; however there is no evidence of inflammation in these lesions. Consistent with this, respiratory papillomas do not contain TH1-like CD4(+) T-cells or cytotoxic CD8(+) T-cells, but instead contain a predominance of TH2-like and T regulatory cells (Tregs). In addition, papillomas also are infiltrated with immature Langerhans cells (iLCs). In this study, we show that papilloma cells express IL-36γ protein, and that human keratinocytes transduced with HPV11 have reduced IL-36γ secretion. We now provide the first evidence that peripheral blood-derived iLCs respond to IL-36γ by expressing inflammatory cytokines and chemokines. When stimulated with IL-36γ, iLCs from patients with RRP had lower expression levels of the TH2-like chemokine CCL-20 as compared with controls. Patients' iLCs also had decreased steady state levels of CCL-1, which is a proinflammatory chemokine. Moreover, CCL-1 levels in iLCs inversely correlated with the severity of RRP. The combined decrease of TH1- and a TH2-like chemokines by iLCs from patients could have consequences in the priming of IFN-γ expression by CD8(+) T-cells. Taken together, our results suggest that, in RRP, there is a defect in the proinflammatory innate immune responses made by iLCs in response to IL-36γ. The consequence of this defect may lead to persistent HPV infection by failing to support an effective HPV-specific, TH1-like and/or Tc1-like adaptive response, thus resulting in the predominant TH2-like and/or Treg micromilieu present in papillomas.

Concurrent oral human papilloma virus infection in patients with recurrent respiratory papillomatosis: a preliminary study

OBJECTIVES/HYPOTHESIS

To determine oral human papilloma virus (HPV) colonization in patients with adult-onset recurrent respiratory papillomatosis (AO-RRP) and their long-term partners.

STUDY DESIGN

Prospective, cohort study

METHODS

Patients with pathology-confirmed AO-RRP and a small cohort of their long-term partners were subjected to a standardized oral rinse and swab protocol to obtain oral epithelial cells. DNA from these samples was extracted and subjected to both qualitative analyses via multiplex polymerase chain reaction as well as to a commercially available linear array assay for the determination of specific HPV subtypes.

RESULTS

Samples were collected from 27 patients with AO-RRP and six long-term sexual partners. Qualitative analysis of agarose gel products using a multiple genotype primer cocktail suggested the presence of HPV DNA in oral rinse or swabs in 26 patients (96%) and four partner samples (67%). A subset of these positive patient samples was then subjected to genotyping; a spectrum of HPV subtypes was observed. Interestingly, HPV81 was identified in many samples.

CONCLUSION

Recent data suggest that less than 7% of the general population is HPV positive in the oral cavity. Our data suggest that the oral colonization rate is much higher in patients with AO-RRP. Additionally, long-term sexual partners of patients with RRP had a much higher rate of HPV positivity. These preliminary data may have implications for viral transmission and provide a framework for enhanced patient education as well as further investigation.

LEVEL OF EVIDENCE

4.

Genetic dysregulation in recurrent respiratory papillomatosis

OBJECTIVES/HYPOTHESIS

Recurrent respiratory papillomatosis (RRP) is a devastating disease, caused by infection of the upper aerodigestive tract with human papillomavirus types 6 and 11. There is no cure for RRP, and surgical removal is the mainstay of treatment. The purpose of this project was to compare genes of cell cycle, apoptosis, and inflammatory cytokines in laryngeal papilloma versus normal tissue for a better understanding of the molecular mechanisms of the disease to discover novel therapies.

STUDY DESIGN

Basic science research study.

METHODS

Papilloma tissue was obtained from patients requiring surgical debridement. For comparison, normal mucosa was obtained from the excised uvula of patients undergoing uvulopalatopharyngoplasty. Total RNA was extracted from both groups and then probed using customized reverse transcriptase real time polymerase chain reaction gene arrays.

RESULTS

The custom arrays examine expression of 84 separate genes within the cell cycle, apoptosis, and inflammatory cytokine pathways. Our findings based on 11 papilloma samples run in comparison to normal mucosa shows that the MCL-1 gene of the apoptosis pathway is significantly downregulated. cytokine genes IL1-A, IL-8, IL-18, and IL-31 are also significantly dysregulated.

CONCLUSIONS

Genes of cell cycle and apoptosis are generally upregulated and downregulated, respectively, as expected in papilloma tissue, with MCL-1 achieving significance when compared to normal tissue. The finding of particular interest is that inflammatory cytokine genes were significantly downregulated, including IL1-A, IL-18, and IL-31. This finding may explain why patients infected with the virus are unable to mediate a T-cell immune clearance of their disease.

Risk factors for the development and severity of juvenile-onset recurrent respiratory papillomatosis: a systematic review

OBJECTIVES

Juvenile-onset recurrent respiratory papillomatosis (JoRRP) is a rare yet aggressive disease caused by human papillomavirus (HPV). Although many newborns are likely exposed to HPV, few develop JoRRP and the clinical course of the disease varies from one child to another. This systematic review seeks to provide an up-to-date understanding of the risk factors for acquisition and severity.

METHODS

We conducted a comprehensive literature search in EMBASE, MEDLINE and EBMR databases using various combinations of keywords related to JoRRP etiology, risk factors and severity. We also searched Google Scholar and the reference lists of eligible studies. Our search was limited to original studies published in French or English between 1995 and July 2012 and to patients under 20 years of age.

RESULTS

Of 1362 citations, we retrieved 102 articles and found 14 additional studies. We retained 32 studies meeting inclusion criteria. All were observational and together included 2296 JoRRP cases. Risk factors could be classified mainly as maternal and birth history, viral genotype, and host factors. A history of genital warts during pregnancy and delivery was strongly linked to the development of JoRRP. Depending on ethnicity, specific human leukocyte antigen class II alleles and immune response factors were important determinants of JoRRP acquisition and severity. HPV-11 genotype and younger age at onset of JoRRP were important predictors of severity.

CONCLUSIONS

Genetic and immunological profiles underlying the acquisition and clinical course are not readily modifiable. Thus, preventing condylomas in women of childbearing age could reduce the burden of this life-threatening disease.

A Decade of Global mRNA and miRNA Profiling of HPV-Positive Cell Lines and Clinical Specimens

For more than a decade, global gene expression profiling has been extensively used to elucidate the biology of human papillomaviruses (HPV) and their role in cervical- and head-and-neck cancers. Since 2008, the expression profiling of miRNAs has been reported in multiple HPV studies. Two major strategies have been employed in the gene and miRNA profiling studies: In the first approach, HPV positive tumors were compared to normal tissues or to HPV negative tumors. The second strategy relied on analysis of cell cultures transfected with single HPV oncogenes or with HPV genomes compared to untransfected cells considered as models for the development of premalignant and malignant transformations.In this review, we summarize what we have learned from a decade of global expression profiling studies. We performed comprehensive analysis of the overlap of the lists of differentially expressed genes and microRNAs, in both tissue samples and cell culture based studies. The review focuses mainly on HPV16, however reports from other HPV species are used as references. We discuss the low degree of consensus among different studies and the limitation of differential expression analysis as well as the fragmented miRNA-mRNA target correlation evidence. Furthermore, we propose an approach for future research to include more comprehensive miRNA-mRNA target correlation analysis and to apply systems biology/gene networks methodology.

T(H)2-like chemokine patterns correlate with disease severity in patients with recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP), characterized by the recurrent growth of benign tumors of the respiratory tract, is caused by infection with human papillomavirus (HPV), predominantly types 6 and 11. Surgical removal of these lesions can be required as frequently as every 3 to 4 wks to maintain a patent airway. There is no approved medical treatment for this disease. In this study, we have characterized the T(H)2-like chemokine profile (CCL17, CCL18, CCL20, CCL22) in patients with RRP and asked whether it was modulated in patients who had achieved significant clinical improvement. CCL17, CCL18 and CCL22 messenger RNAs (mRNAs) were increased in papillomas compared with clinically normal laryngeal epithelium of the RRP patients. Overall, CCL20 mRNA expression was not increased, but there was intense, selective CCL20 protein expression in the basal layer of the papillomas. Patients with RRP expressed more CCL17 (p = 0.003), CCL18 (p = 0.0003), and CCL22 (p = 0.007) in their plasma than controls. Plasma CCL18 decreased over time in three patients enrolled in a pilot clinical trial of celecoxib, and the decrease occurred in conjunction with clinical improvement. There was a significant correlation between sustained clinical remission in additional patients with RRP and reduced levels of CCL17 (p = 0.01), CCL22 (p = 0.002) and CCL18 (p = 0.05). Thus, the change in expression of these three plasma T(H)2-like chemokines may, with future studies, prove to serve as a useful biomarker for predicting disease prognosis.

Recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is a rare, benign disease with no known cure. RRP is caused by infection of the upper aerodigestive tract with the human papillomavirus (HPV). Passage through the birth canal is thought to be the initial transmission event, but infection may occur in utero. HPV vaccines have helped to provide protection from cervical cancer; however, their role in the prevention of RRP is undetermined. Clinical presentation of initial symptoms of RRP may be subtle. RRP course varies, and current management focuses on surgical debulking of papillomatous lesions with or without concurrent adjuvant therapy.

IL-36α exerts pro-inflammatory effects in the lungs of mice

Interleukin (IL-) 36 cytokines (previously designated as novel IL-1 family member cytokines; IL-1F5- IL-1F10) constitute a novel cluster of cytokines structurally and functionally similar to members of the IL-1 cytokine cluster. The effects of IL-36 cytokines in inflammatory lung disorders remains poorly understood. The current study sought to investigate the effects of IL-36α (IL-1F6) and test the hypothesis that IL-36α acts as a pro-inflammatory cytokine in the lung in vivo. Intratracheal instillation of recombinant mouse IL-36α induced neutrophil influx in the lungs of wild-type C57BL/6 mice and IL-1αβ(-/-) mice in vivo. IL-36α induced neutrophil influx was also associated with increased mRNA expression of neutrophil-specific chemokines CXCL1 and CXCL2 in the lungs of C57BL/6 and IL-1αβ(-/-) mice in vivo. In addition, intratracheal instillation of IL-36α enhanced mRNA expression of its receptor IL-36R in the lungs of C57BL/6 as well as IL-1αβ(-/-) mice in vivo. Furthermore, in vitro incubation of CD11c(+) cells with IL-36α resulted in the generation of neutrophil-specific chemokines CXCL1, CXCL2 as well as TNFα. IL-36α increased the expression of the co-stimulatory molecule CD40 and enhanced the ability of CD11c(+) cells to induce CD4(+) T cell proliferation in vitro. Furthermore, stimulation with IL-36α activated NF-κB in a mouse macrophage cell line. These results demonstrate that IL-36α acts as a pro-inflammatory cytokine in the lung without the contribution of IL-1α and IL-1β. The current study describes the pro-inflammatory effects of IL-36α in the lung, demonstrates the functional redundancy of IL-36α with other agonist cytokines in the IL-1 and IL-36 cytokine cluster, and suggests that therapeutic targeting of IL-36 cytokines could be beneficial in inflammatory lung diseases.

Integrative analyses reveal novel strategies in HPV11,-16 and -45 early infection

The interaction between human papillomavirus (HPV) and host cells is not well understood. We investigate the early stage of HPV infections by global expression profiling in a cell model, in which HaCaT cells were transfected with HPV11, HPV16 or HPV45 genomes. We report the differential expression of genes not previously implicated in HPV biology, such as the PSG family and ANKRD1, and of genes implicated in the biology of other viruses, e.g. MX1, IFI44 and DDX60. Carcinogenesis-related genes, e.g. ABL2, MGLL and CYR61, were upregulated by high-risk HPV16 and -45. The integrative analysis revealed the suppression of DNA repair by HPV11 and -16, and downregulation of cytoskeleton genes by all HPV types. Various signalling pathways were affected by the HPVs: IL-2 by HPV11; JAK-STAT by HPV16; and TGF-β, NOTCH and tyrosine kinase signalling by HPV45. This study uncovered novel strategies employed by HPV to establish infection and promote uncontrolled growth.

Constitutive overexpression of the oncogene Rac1 in the airway of recurrent respiratory papillomatosis patients is a targetable host-susceptibility factor

Recurrent respiratory papillomatosis (RRP) is caused by human papillomaviruses (HPVs), primarily types 6 and 11. The disease is characterized by multiple recurrences of airway papillomas, resulting in high levels of morbidity and significant mortality. The prevalence of latent HPV in the larynx of the general population is much greater than the prevalence of RRP, suggesting a host-susceptibility factor for disease. We report that the oncogene Rac1 and its downstream product cyclooxygenase-2 (COX-2) are both constitutively expressed at high levels throughout the airway of these patients, independent of active HPV infection. Use of the COX-2 inhibitor celecoxib in primary papilloma cell culture resulted in the downregulation of HPV transcription. Furthermore, a proof-of-principle study treating three patients with severe RRP with celecoxib resulted in remission of disease in all cases. Therefore, we have identified the first pharmacologically targetable host-susceptibility pathway that contributes to RRP recurrence.

Immune suppression in premalignant respiratory papillomas: enriched functional CD4+Foxp3+ regulatory T cells and PD-1/PD-L1/L2 expression

PURPOSE

Respiratory papillomas, caused by human papillomaviruses types 6 and 11 (HPV6/11), are premalignant lesions with potential for malignant conversion. The cytokine and chemokine micromilieu of papillomas is T(H)2-like with a marked absence of IFN-γ expression. To illuminate why patients with recurrent respiratory papillomatosis (RRP) fail to effectively control their disease, we further investigated the suppressive cellular microenvironment in papillomas.

EXPERIMENTAL DESIGN

CD4(+)CD25(+)CD127(low/-)Foxp3(+) regulatory T cells (Treg) and CD4(+)CD25(-)CD127(low/-)Foxp3(-) T cells within papillomas were characterized and isolated. Their suppressor function was measured by inhibition of peripheral blood mononuclear cell (PBMC) proliferation. Expression of PD-1, CD69, and Helios was identified on these T cells. PD-L1, PD-L2, CCL17, and CCL22 mRNA was also identified in papillomas by quantitative PCR.

RESULTS

Functional Tregs were markedly enriched in papillomas and strongly inhibited anti-CD3 and anti-CD28 antibody activated PBMC proliferation. The natural Treg marker Helios was reduced on Tregs from papillomas, indicating that the majority of Tregs in papillomas are adaptive. The majority of the papilloma-derived CD4(+) T cells expressed the CD4(+)CD25(-)CD127(low/-)Foxp3(-)PD1(+)CD69(+) phenotype and failed to suppress PBMC proliferation, suggesting that they are chronically activated and exhausted. The Treg-attracting chemokine CCL22 was equally expressed by all laryngeal tissues examined. However, CCL17 was robustly expressed by papillomas compared with unaffected laryngeal tissues from RRP patients and individuals without RRP. PD-L1 was elevated in papillomas compared with control laryngeal tissues.

CONCLUSIONS

Papilloma CD4(+) T cells are enriched with functional Tregs, and the adaptive Helios(-) Treg fraction was increased within the T(H)2-like papilloma micromilieu. CD4(+)CD25(-)CD127(low/-)Foxp3(-) T-cells failed to suppress PBMC proliferation and may be exhausted. The PD-1/PDL-1 pathway may represent an additional immunosuppressive mechanism that contributes to defective HPV6/11 clearance in RRP.

Recurrent respiratory papillomatosis: a complex defect in immune responsiveness to human papillomavirus-6 and -11

Recurrent respiratory papillomatosis (RRP) is a rare disease of the larynx caused by infection with human papillomaviruses (HPV) -6 or -11, associated with significant morbidity and on occasion mortality. Here we summarize our current understanding of the permissive adaptive and innate responses made by patients with RRP that support chronic HPV infection and prevent immune clearance of these viruses. Furthermore, we provide new evidence of T(H)2-like polarization in papillomas and blood of patients with RRP, restricted CD4 and CD8 Vbeta repertoires, the effect of HPV-11 early protein E6 on T-cell alloreactivity, enriched Langerhans cell presence in papillomas, and evidence that natural killer cells are dysfunctional in RRP. We review the immunogenetic mechanisms that regulate the dysfunctional responses made by patients with RRP in response to HPV infection of the upper airway. In addition, we are identifying T-cell epitopes on HPV-11 early proteins, in the context of human leukocyte antigen (HLA) class II alleles enriched in RRP that should help generate a therapeutic vaccine. Taken together, RRP is a complex, multigene disease manifesting as a tissue and HPV-specific, immune deficiency that prevents effective clearance and/or control of HPV-6 and -11 infection.

The natural history of human papillomavirus infections of the mucosal epithelia

Human papillomaviruses (HPVs), members of a very large family of small DNA viruses, cause both benign papillomas and malignant tumors. While most research on these viruses over the past 30 years has focused on their oncogenic properties in the genital tract, they also play an important role in diseases of the upper aerodigestive tract. Rapidly accelerating advances in knowledge have increased our understanding of the biology of these viruses and this knowledge, in turn, is being applied to new approaches to prevent, diagnose, and treat HPV-induced diseases. In this introductory article, we provide an overview of the structure and life cycle of the mucosal HPVs and their interactions with their target tissues and cells. Finally, we provide our thoughts about treatments for HPV-induced diseases, present and future.