Development of Antibodies against HPV-6 and HPV-11 for the Study of Laryngeal Papilloma.

Laryngeal papilloma (LP), which is associated with infection by human papillomavirus (HPV)-6 or -11, displays aggressive growth. The precise molecular mechanism underlying the tumorigenesis of LP has yet to be uncovered. Building on our earlier research into HPV-6, in this study, the viral gene expression of HPV-11 was investigated by quantitative PCR and DNA/RNA in situ hybridization. Additionally, newly developed antibodies against the E4 protein of HPV-6 and HPV-11 were evaluated by immunohistochemistry. The average viral load of HPV-11 in LP was 1.95 ± 0.66 × 105 copies/ng DNA, and 88% of HPV mRNA expression was found to be E4, E5a, and E5b mRNAs. According to RNA in situ hybridization, E4 and E5b mRNAs were expressed from the middle to upper part of the epithelium. E4 immunohistochemistry revealed a wide positive reaction in the upper cell layer in line with E4 mRNA expression. Other head and neck lesions with HPV-11 infection also showed a positive reaction in E4 immunohistochemistry. The distribution pattern of HPV DNA, viral mRNA, and E4 protein in LP with HPV-11 infection was quite similar to that of HPV-6. Therefore, it might be possible to apply these E4-specific antibodies in other functional studies as well as clinical applications, including targeted molecular therapies in patients with HPV-6 and HPV-11 infection.

Neutralization sites of human papillomavirus-6 relate to virus attachment and entry phase in viral infection.

Human papillomavirus type 6 (HPV6) is the major etiologic agent of genital warts and recurrent respiratory papillomatosis. Although the commercial HPV vaccines cover HPV6, the neutralization sites and mode for HPV6 are poorly understood. Here, we identify the HPV6 neutralization sites and discriminate the inhibition of virus attachment and entry by three potent neutralizing antibodies (nAbs), 5D3, 17D5, and 15F7. Mutagenesis assays showed that these nAbs predominantly target surface loops BC, DE, and FG of HPV6 L1. Cryo-EM structures of the HPV6 pseudovirus (PsV) and its immune complexes revealed three distinct binding modalities - full-occupation-bound to capsid, top-center-bound-, and top-rim-bound to pentamers - and illustrated a structural atlas for three classes of antibody-bound footprints that are located at center-distal ring, center, and center-proximal ring of pentamer surface for 5D3, 17D5, and 15F7, respectively. Two modes of neutralization were identified: mAb 5D3 and 17D5 block HPV PsV from attaching to the extracellular matrix (ECM) and the cell surface, whereas 15F7 allows PsV attachment but prohibits PsV from entering the cell. These findings highlight three neutralization sites of HPV6 L1 and outline two antibody-mediated neutralization mechanisms against HPV6, which will be relevant for HPV virology and antiviral inhibitor design. HighlightsMajor neutralization sites of HPV6 were mapped on the pseudovirus cryo-EM structuremAb 15F7 binds HPV6 capsid with a novel top-rim binding modality and confers a post-attachment neutralizationmAb 17D5 binds capsid in top-centre manner but unexpectedly prevents virus from attachment to cell surface.

High-throughput screening identifies candidate drugs for the treatment of recurrent respiratory papillomatosis.

Recurrent respiratory papillomatosis (RRP) is a benign neoplasm of the larynx caused mainly by human papillomavirus type 6 or 11 and its standard treatment involves repeated surgical debulking of the laryngeal tumors. However, significant morbidity and occasional mortality due to multiple recurrences occur. Conditional reprogramming (CR) was used to establish a HPV-6 positive culture from an RRP patient, named GUMC-403. High-throughput screening was performed at the National Center for Advanced Technology (NCATS) to identify potential drugs to treat this rare but morbid disease. GUMC-403 cells were screened against the NPC library of >2800 approved drugs and the MIPE library of >1900 investigational drugs to identify new uses for FDA-approved drugs or drugs that have undergone significant research and development. From the two libraries, we identified a total of 13 drugs that induced significant cytotoxicity in RRP cells at IC50 values that were clinically achievable. We validated the efficacy of the drugs in vitro using CR 2D and 3D models and further refined our list of drugs to panobinostat, dinaciclib and forskolin as potential therapies for RRP patients.

Age at diagnosis, but not HPV type, is strongly associated with clinical course in recurrent respiratory papillomatosis.

BACKGROUND: Recurrent Respiratory Papillomatosis (RRP) is a rare disease characterized by the growth of papillomas in the airway and especially the larynx. The clinical course is highly variable among individuals and there is poor understanding of the factors that drive an aggressive vs an indolent course. METHODS: A convenience cohort of 339 affected subjects with papillomas positive for only HPV6 or HPV11 and clinical course data available for 1 year or more, from a large multicenter international study were included. Exploratory data analysis was conducted followed by inferential analyses with frequentist and Bayesian statistics. RESULTS: We examined 339 subjects: 82% were diagnosed prior to the age of 18 years, 65% were infected with HPV6, and 69% had an aggressive clinical course. When comparing age at diagnosis with clinical course, the probability of aggressiveness is high for children under five years of age then drops rapidly. For patients diagnosed after the age of 10 years, an indolent course is more common. After accounting for confounding between HPV11 and young age, HPV type was minimally associated with aggressiveness. Fast and Frugal Trees (FFTs) were utilized to determine which algorithms yield the highest accuracy to classify patients as having an indolent or aggressive clinical course and consistently created a branch for diagnostic age at ~5 years old. There was no reliable strong association between clinical course and socioeconomic or parental factors. CONCLUSION: In the largest cohort of its type, we have identified a critical age at diagnosis which demarcates a more aggressive from less aggressive clinical course.

EphrinB1: novel microtubule associated protein whose expression affects taxane sensitivity.

Microtubules (MTs) are components of the cytoskeleton made up of polymerized alpha and beta tubulin dimers. MT structure and function must be maintained throughout the cell cycle to ensure proper execution of mitosis and cellular homeostasis. The protein tyrosine phosphatase, PTPN13, localizes to distinct compartments during mitosis and cytokinesis. We have previously demonstrated that the HPV16 E6 oncoprotein binds PTPN13 and leads to its degradation. Thus, we speculated that HPV infection may affect cellular proliferation by altering the localization of a PTPN13 phosphatase substrate, EphrinB1, during mitosis. Here we report that EphrinB1 co-localizes with MTs during all phases of the cell cycle. Specifically, a cleaved, unphosphorylated EphrinB1 fragment directly binds tubulin, while its phosphorylated form lacks MT binding capacity. These findings suggest that EphrinB1 is a novel microtubule associated protein (MAP). Importantly, we show that in the context of HPV16 E6 expression, EphrinB1 affects taxane response in vitro. We speculate that this reflects PTPN13's modulation of EphrinB1 phosphorylation and suggest that EphrinB1 is an important contributor to taxane sensitivity/resistance phenotypes in epithelial cancers. Thus, HPV infection or functional mutations of PTPN13 in non-viral cancers may predict taxane sensitivity.

Dysphonia as a sign of HPV laryngeal infection: a case report.

BACKGROUND: Voice dysfunction or dysphonia may be associated with several clinical conditions. Among these, laryngeal human papillomavirus (HPV)-induced lesions should be considered as a possible causative factor. We report a case of dysphonia in a patient presenting with an HPV laryngeal lesion. We also discuss the clinical features of the disease, its histopathological findings, and treatment and rigorous follow-up. CASE PRESENTATION: We report a case of laryngeal papilloma in a 29-year-old, Afro-descendant, male patient with dysphonia. He was a non-smoker and was not a drug user. Videolaryngostroboscopy revealed signs suggestive of pharyngolaryngeal reflux. The right vocal fold presented with a papillomatous aspect in the posterior third, which underwent excision. Histopathological examination showed a nodular lesion of the right vocal fold, conclusive of squamous papilloma with absence of malignancy. CONCLUSION: Patients presenting with persistent voice dysfunction or dysphonia should be investigated for possible laryngeal HPV infection. Diagnostic confirmation by HPV genotyping is important for follow-up of potential recurrence.

Long-term study of a quadrivalent human papillomavirus vaccine.

BACKGROUND: We present a long-term safety, immunogenicity, and effectiveness study of a quadrivalent human papillomavirus (HPV4) vaccine. METHODS: Sexually naive boys and girls aged 9 to 15 years (N = 1781) were assigned (2:1) to receive HPV4 vaccine or saline placebo at day 1 and months 2 and 6. At month 30, the placebo group (n = 482) received HPV4 vaccine following the same regimen and both cohorts were followed through month 96. Subjects ≥ 16 years were eligible for effectiveness evaluations. The primary objective was to evaluate the long-term anti-HPV6/11/16/18 serological levels. The secondary objective was to estimate vaccine effectiveness against HPV6/11/16/18-related persistent infection or disease. RESULTS: For each of the HPV4 vaccine types, vaccination-induced anti-HPV response persisted through month 96. Among 429 subjects who received HPV4 vaccine at a mean age of 12, none developed HPV6/11/16/18-related disease or persistent infection of ≥ 12 months' duration. Acquisition of new sexual partners (among those ≥ 16 years) was ∼1 per year. Subjects receiving HPV4 vaccine at month 30 (mean age 15 years) had a similar baseline rate of seropositivity to ≥ 1 of the 4 HPV types to those vaccinated at day 1 (mean age 12 years; 1.9% [9 of 474] vs 1.7% [20 of 1157]); however, 4 of the 9 subjects vaccinated at the later age were seropositive to 3 vaccine types, indicating previous HPV exposure. No new significant serious adverse events were observed for 8 years postvaccination in both genders. CONCLUSIONS: When administered to adolescents, the HPV4 vaccine demonstrated durability in clinically effective protection and sustained antibody titers over 8 years.

Condiloma gigante (tumor de Buschke-L÷wenstein) de la vulva / Giant condyloma (Buschke-Lowenstein tumor) of the vulva

El condiloma gigante o tumor de Buschke-Löwenstein, a pesar de ser considerado una entidad benigna debido a sus características anatomopatológicas, presenta una alta capacidad de recurrencia y transformación maligna, con una mortalidad del 20 por ciento. Se presenta el caso de una paciente con un tumor de Buschke-Löwenstein de 5 años de evolución que tomó vulva y ocluyó el orificio vaginal con extensión periuretral y ano. El diagnóstico viral mostró la presencia del virus del papiloma humano tipo 6 como único genotipo infectante. Se le aplicó un tratamiento compuesto de cirugía, radioterapia, inmunoterapia y antiviral con resultados satisfactorios. El seguimiento a 5 años mostró la aparición de pequeños condilomas acuminados los cuales fueron tratados con ácido tricloroacético. Es de gran importancia realizar un diagnóstico clínico y anatomopatológico del tumor de Buschke-Löwenstein previo al tratamiento, con vista a definir el grado de penetración e invasión local. La cirugía con amplio margen con o sin otros tratamientos adicionales es la terapéutica más eficaz reportada en el manejo de esta afección. Un seguimiento clínico de las pacientes permite detectar la posible recurrencia de la enfermeda(AU)

In spite of being considered a benign entity due to anatomo-pathological characteristics, giant Condylom or Buschke-L÷wenstein tumour has a high capacity of recurrence and malignant transformation, with a 20 percent of mortality. To present a patient's case that has a Buschke-L÷wenstein tumour of 5 years of evolution, that involved the vulvae, periuretral, anus and vagina. Viral diagnostics showed a presence of the Human Papillomavirus type 6 as the only infecting genotype. Surgery, radiotherapy, immunotherapy and antiviral treatments were applied to her with satisfactory results. The follow up 5 years showed arising of smalls condyloma acuminatum which were treated with tricloroacetic acid. A clinical and anatomo-pathological diagnosis of the Buschke-L÷wenstein tumour in order to define the penetration´s grade and local invasion, it is necessary before the treatment. The wide margin surgery with or without additional treatment is the most efficient therapeutic reported in handling this pathology. A continuous clinical following allows to detect a possible recurrence of this disease(AU)

Association of high-risk human papillomavirus infection with oral epithelial dysplasia.

OBJECTIVE: The aim of this study was to evaluate cases of oral epithelial dysplasia for biologically significant human papillomavirus (HPV) infection. STUDY DESIGN: Forty consecutive cases of high-grade dysplasia and 37 cases of low-grade dysplasia were examined for p16(INK4a) expression by immunohistochemistry. High-risk HPV infection was assessed in p16-positive cases using in situ hybridization. Proliferation index was assessed with MIB-1 immunohistochemistry. RESULTS: Eleven of 40 high-grade dysplasias and one of 37 low-grade dysplasias were p16 positive. High-risk HPV was detected in seven cases of p16-positive high-grade dysplasia. The difference between high- and low-grade dysplasia was statistically significant (P = .01). HPV-positive high-grade dysplasias showed a distinctive histologic appearance and MIB-1 labeling pattern. Most high-risk HPV-positive cases were seen in the floor of mouth. CONCLUSION: High-risk HPV was associated with a subset of cases of severe epithelial dysplasia/carcinoma in situ that demonstrated diffuse loss of squamous differentiation and a high proliferation index.

Genital warts and infection with human immunodeficiency virus in high-risk women in Burkina Faso: a longitudinal study.

BACKGROUND: Human papillomaviruses are the most common sexually transmitted infections, and genital warts, caused by HPV-6 and 11, entail considerable morbidity and cost. The natural history of genital warts in relation to HIV-1 infection has not been described in African women. We examined risk factors for genital warts in a cohort of high-risk women in Burkina Faso, in order to further describe their epidemiology. METHODS: A prospective study of 765 high-risk women who were followed at 4-monthly intervals for 27 months in Burkina Faso. Logistic and Cox regression were used to identify factors associated with prevalent, incident and persistent genital warts, including HIV-1 serostatus, CD4+ count, and concurrent sexually transmitted infections. In a subset of 306 women, cervical HPV DNA was tested at enrollment. RESULTS: Genital wart prevalence at baseline was 1.6% (8/492) among HIV-uninfected and 7.0% (19/273) among HIV-1 seropositive women. Forty women (5.2%) experienced at least one incident GW episode. Incidence was 1.1 per 100 person-years among HIV-uninfected women, 7.4 per 100 person-years among HIV-1 seropositive women with a nadir CD4+ count >200 cells/µL and 14.6 per 100 person-years among HIV-1 seropositive women with a nadir CD4+ count ≤ 200 cells/µL. Incident genital warts were also associated with concurrent bacterial vaginosis, and genital ulceration. Antiretroviral therapy was not protective against incident or persistent genital warts. Detection of HPV-6 DNA and abnormal cervical cytology were strongly associated with incident genital warts. CONCLUSIONS: Genital warts occur much more frequently among HIV-1 infected women in Africa, particularly among those with low CD4+ counts. Antiretroviral therapy did not reduce the incidence or persistence of genital warts in this population.

Development of genital warts after incident detection of human papillomavirus infection in young men.

Determining the rate at which men develop genital warts after infection with alpha genus human papillomavirus (HPV) types will provide important information for the design of prevention strategies. We conducted a cohort study of 18-21-year-old men who underwent triannual genital examinations. The 24-month cumulative genital wart incidence was 57.9% (95% confidence interval [CI], 38.1%-79.1%) among 46 men with incident detection of HPV-6 or HPV-11 infection, 2.0% (95% CI, 0.5%-7.9%) among 161 men with incident detection of infection with other HPV types, and 0.7% (95% CI, 0.2%-2.8%) among 331 men who tested negative for HPV. Our results suggest that genital warts are common after HPV-6 or HPV-11 infection in young men.

Local hyperthermia could induce antiviral activity by endogenous interferon-dependent pathway in condyloma acuminata.

Local hyperthermia has been successfully used in the treatment of viral warts by mechanisms that have largely remained unclear. Using an organotypic culture system, we found that hyperthermia at 42 °C and 45 °C could induce a significant increase in the transcriptional expression of interferon (IFN)-α, IFN-ß and IFN-γ, in a temperature-dependent manner in condyloma acuminata (CA), but not in normal skin. Accordingly, local hyperthermia could enhance the expression of 2'-5' oligoadenylate synthase and double-stranded RNA (dsRNA)-dependent protein kinase, two antiviral enzymes downstream of the IFN-dependant pathway. Hyperthermia led to an increase in IFN-α/ß receptor transcripts, and an increase in the levels in phospho-Stat1 and phospho-Stat2 in CA, though it had no influence on the levels of Jak1, Tyk2, Stat1 and Stat2 transcriptional expression. Local hyperthermia was proved effective in treating human papillomavirus-infected skin. These results suggested that hyperthermia took effect partly by inducing the expression of local endogenous IFN and partly by subsequent IFN-induced antiviral activity via Jak-STATs signalling pathway in CA.

Human papillomavirus as an independent predictor in oral squamous cell cancer.

AIM: There is an increasing evidence for the role of high risk human papillomavirus (HPV) in the pathogenesis of oral squamous cell carcinoma (OSCC). The purpose of this study is to evaluate the relevance of HPV infection to the survival and prognosis of OSCC. METHODOLOGY: Fifty-two patients with OSCC were followed from 4 to 88 months with a median of 50.7 months. HPV DNA was identified in formalin-fixed, paraffin-embedded tumor specimens by nested PCR with MY09/MY11 and GP5+/GP6+ primer pairs and the HPV genotype was determined by direct DNA sequencing. Association between the HPV status and risk factors for cancer as well as tumor-host characteristics were analyzed. Survival curves were calculated by the Kaplan-Meier method and analyzed using the log-rank test. RESULTS: HPV was found in 40.4% of the tumors with HPV16 accounting for 63.5%, HPV18 for 30.8%, HPV6 for 3.9% and HPV11 for 1.8%. No infection with more than one HPV genotype was detected. HPV infection was significantly associated with poor histological grade, TNM stage I-II, alcohol usage and no smoking status. Multivariate analysis showed that HPV had an independent prognostic effect on the overall survival after adjusting other confounding factors such as histological grade, TNM stage and tobacco usage. The presence of HPV was significantly correlated with a better survival in patients with OSCC. CONCLUSION: HPV infection can act as an independent predictor for the survival and prognosis of OSCC.

Cell polarity proteins: common targets for tumorigenic human viruses.

Loss of polarity and disruption of cell junctions are common features of epithelial-derived cancer cells, and mounting evidence indicates that such defects have a direct function in the pathology of cancer. Supporting this idea, results with several different human tumor viruses indicate that their oncogenic potential depends in part on a common ability to inactivate key cell polarity proteins. For example, adenovirus (Ad) type 9 is unique among human Ads by causing exclusively estrogen-dependent mammary tumors in experimental animals and in having E4 region-encoded open reading frame 1 (E4-ORF1) as its primary oncogenic determinant. The 125-residue E4-ORF1 protein consists of two separate protein-interaction elements, one of which defines a PDZ domain-binding motif (PBM) required for E4-ORF1 to induce both cellular transformation in vitro and tumorigenesis in vivo. Most notably, the E4-ORF1 PBM mediates interactions with a selected group of cellular PDZ proteins, three of which include the cell polarity proteins Dlg1, PATJ and ZO-2. Data further indicate that these interactions promote disruption of cell junctions and a loss of cell polarity. In addition, one or more of the E4-ORF1-interacting cell polarity proteins, as well as the cell polarity protein Scribble, are common targets for the high-risk human papillomavirus (HPV) E6 or human T-cell leukemia virus type 1 (HTLV-1) Tax oncoproteins. Underscoring the significance of these observations, in humans, high-risk HPV and HTLV-1 are causative agents for cervical cancer and adult T-cell leukemia, respectively. Consequently, human tumor viruses should serve as powerful tools for deciphering mechanisms whereby disruption of cell junctions and loss of cell polarity contribute to the development of many human cancers. This review article discusses evidence supporting this hypothesis, with an emphasis on the human Ad E4-ORF1 oncoprotein.

Two different HPV-11E6 fusion proteins trap p53 in the cytoplasm and induce apoptosis.

Mucosal high risk human papillomaviruses (HPVs) have been shown to be the major cause of cervical cancer. However, the reason why the low risk HPVs only cause proliferative but non-invasive lesions of infected epithelia remains elusive. Because p53 interacts with high risk HPVs E6 and plays a very important role in carcinogenesis, it is assumed that low risk HPVs E6 might interact with p53 in a different pattern. We used mammalian green fluorescent protein (GFP) tagged and polyhistidine (His) tagged proteins expression systems to express HPV-11E6 fusion proteins in wild-type (wt)p53 cell lines, such as 293T and MCF-7 cells to trace the traffic and location of E6s and p53. We showed that: (1) Following transfection, HPV-11E6 was predominantly expressed in the cytoplasm; (2)Using immunocytochemistry and Western blotting, endogenous wt p53 was shown to be trapped in cytoplasm by HPV-11E6 expression. (3) Apoptosis was increased in HPV-11E6 expressed cells. In conclusion, the entrapment of endogenous wt p53 in cytoplasm by the low risk HPV-11E6 may be one of the reasons why low risk HPV is not able to induce malignant transformation.

Human herpesvirus type 6 reactivation after haematopoietic stem cell transplantation.

Human herpesvirus type 6 (HHV6) is known to reactivate after hematopoetic stem cell transplantation (HSCT) and has been suggested to be associated with increased mortality and severe clinical manifestations, including graft versus host disease (GvHD). The exact etiological role of HHV6 reactivation in increased morbidity and mortality after HSCT remains unclear. This review will focus on the current available evidence of HHV6 reactivation after HSCT and its immuno-modulatory capacities, with particular emphasis on the severe complication GvHD. At present, no effective specific antiviral treatment for HHV6 reactivation has been identified. The currently available antiviral agents are outlined, as well as possible future strategies for the treatment of HHV6 reactivation. Non-toxic, specific treatment or prevention of HHV6 reactivation might improve the safety and efficacy of the HSCT procedure.

Treatment patterns and associated costs for genital warts in Italy.

OBJECTIVE: Genital warts are caused by human papillomavirus (HPV), principally types 6 and 11, and are highly contagious. This study assessed treatment patterns and costs of management of genital warts in Italy. RESEARCH DESIGN AND METHODS: This was a retrospective, observational study conducted among gynaecologists, dermatologists, and specialists at sexually transmitted disease clinics in Italy. Resource-use data related to genital warts were collected for patients at risk in the age range 14-64 years examined during 2005. Unit costs were assigned to resource use to provide estimates of the direct, indirect and total costs per case of genital warts. RESULTS: Twenty-eight investigators enrolled 341 patients aged 15-64 years, including 194 (56.9%), 81 (23.7%) and 66 (19.4%) patients with newly diagnosed, recurrent and resistant genital warts, respectively. Most patients (333/341; 97.7%) had at least one outpatient visit, while 43 (12.6%) patients were hospitalised, including 39 patients without an overnight stay (day-hospital cases, 11.4%). Self-applied medication was prescribed for 124 (36.4%) patients. Most outpatient cases (267/333; 80.2%) underwent an office-based procedure. Mean annual direct medical costs per patient, which were funded predominantly by the Italian National Health Service (there was some patient co-payment), were €242 for men and €332 for women. When productivity losses were included, mean total annual costs were €325 for men and €464 for women. CONCLUSIONS: This is the first study of treatment patterns and costs for genital warts in Italy. Treatment patterns differ in some respects from those observed in other European countries, but costs generally appear similar. Despite the limitations of physician selection bias and over-representation of North Italy in the patient sample, the findings of this study may be useful in estimating the cost-effectiveness of introducing a quadrivalent HPV vaccination programme in Italy.