Oncogenic Human Papillomavirus Research Articles

A Cell-Based Renilla Luminescence Reporter Plasmid Assay for High-Throughput Screening to Identify Novel FDA-Approved Drug Inhibitors of HPV-16 Infection.

Like cervical cancer, anal cancer is caused by human papillomavirus (HPV). HPV is the most common sexually transmitted agent and is found in the anal canal of almost all HIV-positive men who have sex with men (MSM). Rates of HPV anal cancer are disproportionately higher in this population. Although the nanovalent HPV vaccine is efficacious in protecting against oncogenic HPV types, a substantial proportion of MSM remains unvaccinated and anal HPV infection continues to be an important public health burden. Therefore, it is important to identify strategies to prevent HPV infection. We report on two promising and interlinked strategies: (1) the development of a cell-based Renilla luminescence reporter assay using HPV-16 pseudovirions that encapsidate SV40-driven Renilla luminescence reporter expression plasmid and (2) use of this assay for high-throughput screening (HTS) of FDA- and internationally approved drugs to identify those that could be repurposed to prevent HPV infection. We conducted a screen of 1906 drugs. The assay was valid with a Z' of 0.67 ± 0.04, percent coefficient of variance of 10.0, and signal-to-background noise window of 424.0 ± 8.0. Five drugs were chosen for further analyses based on selection parameters of ≥77.0% infection of HPV-16 pseudovirion-driven Renilla expression with <20.0% cytotoxicity. Of these, the antifungal pentamidine and a gamma-amino butyric acid receptor agonist securinine exhibited ≥90.0% infection with <10.0% cytotoxicity. This luminescent cell-based reporter expression plasmid assay for HTS is a valid method to identify FDA- and internationally approved drugs with the potential to be repurposed into prevention modalities for HPV infection.

Abstract LB-200: A cGMP-grade chimeric papillomavirus candidate vaccine (HPV16 RG1-VLP) confers long term cross-protection compared to a nonavalent hpv vaccine in a pre-clinical papillomavirus animal model

Abstract Background: The National Cancer Institute (NCI) PREVENT Cancer Program (PREVENT) is a peer-reviewed R&amp;D pipeline with the core emphasis on preclinical development and clinical translation of novel cancer preventive interventions. One of the latest PREVENT-supported projects include cGMP production and IND enabling studies of a broad spectrum experimental human papillomavirus (HPV) vaccine- HPV16 RG1-VLP. This monovalent chimeric virus-like particle (VLP) displays 360 copies of the highly conserved epitope RG1 (aa 17-36 of minor capsid protein HPV16 L2) in the DE loop of HPV16L1 VLP backbone, and is capable of eliciting broadly neutralizing antibodies that target several clinically relevant HPV genotypes. RG-1 induced cross-neutralizing titers are typically lower than anti-L1 antibodies generated by currently licensed HPV vaccines. Hence, durability of protection has been cited as a cause of concern. Here, using engineering-run cGMP grade HPV16-RG1VLPs formulated with alhdyrogel®, the durability of protection 6 month post-vaccination of HPV16 RG1-VLPs against Gardasil-9®, a licensed HPV vaccine was evaluated using an established papillomavirus disease model. Methods: New Zealand white rabbits (n=15 per treatment group) were administered three intra-muscular vaccinations of HPV16-RG1 (80 µg), human doses of Gardasil-9®, or no vaccine (adjuvant only). Following vaccination, in vivo protection was assessed against 8 high-risk oncogenic HPVs utilizing methods from an established cottontail rabbit papillomavirus (CRPV) disease model. Within each treatment group, 5 rabbits were challenged two weeks post-final vaccination (at peak serum ELISA titer), while another 5 were challenged six months post-final vaccination to assess durability of protection. The remainder 5 rabbits will be challenged one year post final vaccination. Results: During the peak-titer period, rabbits vaccinated with monovalent HPV16-RG1VLP were protected from disease development, which was comparable to the protection afforded by Gardasil-9®. Six months after final vaccination, despite lower serum titers, HPV16-RG1VLP immunized rabbits were still protected from disease development with vaccine efficacy comparable to that of Gardasil-9®. And, in some instances, HPV16-RG1VLP vaccine demonstrated a superior cross-protection. Conclusions: Even as a monovalent formulation, HPV16 RG1 VLP vaccination was able to provide comparable protection against a number of high-risk oncogenic HPV types, including types not covered by Gardasil-9®, even after six months post-vaccination. As a monovalent VLP, HPV16 RG1 VLP holds promise as a broad-spectrum preventative vaccine candidate that could potentially provide broader protection at lower production costs. Studies evaluating protection one-year-post vaccination is currently in progress. Citation Format: Jiafen Hu, Karla Balogh, Ken Matsui, Huimin Tan, Pola Olczak, George Buchman, Brian Howard, Jonathan White, Michelle Kennedy, Shizuko Sei, Elizabeth Glaze, Sarah Brendle, Christina Schellenbacher, Reinhard Kirnbauer, Richard Roden, Robert Shoemaker, Neil Christensen, Joshua Weiyuan Wang. A cGMP-grade chimeric papillomavirus candidate vaccine (HPV16 RG1-VLP) confers long term cross-protection compared to a nonavalent hpv vaccine in a pre-clinical papillomavirus animal model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-200.

Anogenital siğiller: İnsan papilloma virüsü, klinik bulguları ve tedavi stratejileri üzerine bir güncelleme

Anogenital warts is a major health problem caused by human papillomavirus (HPV). To date, more than 200 subtypes of HPV exist. Depending on the type of HPV and the immune status of the patient, various clinical forms may appear. The most detected types are HPV 6 and 11 which are responsible for approximately 90% of anogenital warts. High oncogenic strains HPV types 16 and 18 are responsible not only for servical cancer but also other cancers such as vagina, vulva, penis, anus, head and neck. Besides, anogenital warts impact the individual’s quality of life leading significant psychosocial problems. Treatment options for anogenital warts include cytodestructive, immune-mediated and surgical therapies. Treatment choice depends on the location, number, and size of the warts; patient situation (eg, pregnancy, ability to comply with therapy, immunsuppression); availability of clinical expertise; and patient preferences, cost, and convenience. This article updates the epidemiological, etiological, clinical features and therapeutic choices in anogenital warts. Özet

The high-risk HPV oncogene E7 upregulates miR-182 expression through the TGF-β/Smad pathway in cervical cancer.

Accumulating experimental evidence has shown that the aberrant expression of microRNAs (miRNAs) is involved in the development and progression of human cervical cancer. Previously, we identified miR-182 as an oncomiRNA in cervical cancer. However, the mechanism by which miR-182 is regulated and the interaction between human papillomavirus (HPV) and miR-182 in cervical cancer development remains unknown. In the present study, we explored the link between HPV E7 and miR-182 and verified that high-risk HPV E7 upregulated miR-182 expression through TGF-β/Smad4 signaling pathway in cervical cancer. By contrast, low-risk HPV E7 did not affect the expression of TGF-β and miR-182. Mechanistically, as high-risk HPV E7 bound to pRb, E2F was released from the complex and bound to the TGF-β promoter region, resulting in TGF-β overexpression. Furthermore, the Smad4 signaling pathway was activated upon TGF-β overexpression, which led to an interaction between Smad4 and the miR-182 promoter region, subsequently inducing the upregulation of miR-182 in both cervical cancer cells and the surrounding normal cells. In conclusion, this newly identified high-risk HPV E7/TGF-β/miR-182 regulatory network might inform the development of specific therapeutic strategies for cervical cancer.

Frequency Distribution of Various Oncogenes of Human Papillomavirus in Genital Cancerous Lesions in the City of Gorgan

Background: The high-risk types of human papillomavirus (HPV) have been identified as one of the main causes of genital cancers over the recent years, therefore their accurate diagnosis plays an important role in controlling cancer and maintaining the community health. Objectives: Since a primary diagnosis of this virus is not possible through serologic methods and cell culture, the present study has been conducted with the aim to identify and determine the frequency of oncogenic types of HPV from paraffin block samples using PCR. Methods: In this cross-sectional study, which was carried out in 2017, a total amount of 97 genital samples coated in paraffin were collected from precancerous and cancerous lesions. Their DNA was extracted using special kits, and PCR and post PCR techniques were applied using specific primers. Results: 58 samples (59.8%) showed positive results in terms of the presence of HPV DNA, which indicated a high frequency for HPV. Moreover, 56.9% of HPV genotypes were classified under high-risk and 43.1% under low-risk categories, out of which HPV-16 (22.2%), HPV-11 (19%) and HPV-6 (12.7%) had the highest frequencies, respectively. Conclusions: The results of this study show that HPV could be considered as the main factor responsible for the changes in genital tissues is men and women, which have the potential to develop cancer. Furthermore, the involvement of various types of this virus in creating simultaneous and multiple infections further emphasizes the significance of screening and constant control of this virus.

Chromogenic In Situ Hybridization as a Tool for HPV-Related Head and Neck Cancer Diagnosis.

Human papillomavirus (HPV) infection is a major risk factor for a subtype of oropharyngeal squamous cell carcinoma (OPSCC), which tends to be associated with a better outcome than alcohol- and tobacco-related OPSCC. Chromogenic in situ hybridization (CISH) of HPV viral RNA could allow the semiquantitative evaluation of viral transcripts of the oncogenic proteins E6 and E7 and an in situ visualization with a good spatial resolution. This technique allows the diagnosis of an active infection with the visualization of HPV transcription in the tumoral HPV-infected cells. An advantage of this technique is the avoidance of contamination from nonneoplastic HPV-infected cells adjacent to the tumor. Overall, its good diagnosis performances have it considered to be the gold standard for active HPV infection identification. Since E6 and E7 viral protein interaction with cell proteins pRb and p53 is mandatory for cell transformation, HPV RNA CISH is functionally relevant and acutely reflects active oncogenic HPV infection. This technique is clinically relevant as well since "low" or "high" HPV transcription levels helped the identification of two prognosis groups among HPV-related p16-positive head and neck cancer patients. Here we present the protocol for manual HPV RNA CISH performed on formalin-fixed paraffin-embedded (FFPE) slides with a kit obtained from the manufacturer. Instead of chromogenic revelation, RNA in situ hybridization may also be performed with fluorescent revelation (RNA FISH). It may also be combined with conventional immunostaining.

Routine cervical screening by primary HPV testing: early findings in the renewed National Cervical Screening Program.

To report human papillomavirus (HPV) testing patterns and rates of oncogenic HPV-positivity for specimens submitted during the first 6 months after the National Cervical Screening Program switched from cytology- to primary HPV-based screening. Retrospective cross-sectional review of 195606 specimens submitted for HPV testing, 1 December 2017 - 31 May 2018. Large community-based general pathology laboratory in metropolitan Sydney. Prevalence of oncogenic HPV types (all, HPV16/18, non-HPV16/18) by reason for HPV test (primary screening, non-screening); for oncogenic HPV-positive women in the age band recommended for primary HPV screening (25-74 years), prevalence of cytologic abnormality and rates of 12-month follow-up and colposcopy recommendations. 195606 samples were received: 157700 (80.6%) for primary screening, 37906 (19.4%) for non-screening tests. Oncogenic HPV was detected in 8.1% of screening tests (95% CI, 7.9-8.2%) and 20.9% of non-screening tests (95% CI, 20.5-21.3%); 35.5% (95% CI, 34.7-36.4%) of women of recommended screening age with positive oncogenic HPV screening test results also had a cytologic abnormality. The proportion of HPV16/18-positive samples with high grade abnormality was 15.3% (95% CI, 14.2-16.6%); for samples positive for other oncogenic HPV types, the proportion was 6.3% (95% CI, 5.8-6.8%). Repeat HPV testing after 12 months was recommended for 5.4% (95% CI, 5.3-5.5%) and direct colposcopy for 2.6% (95% CI, 2.5-2.7%) of screened women aged 25-74 years. High grade cytologic abnormalities were more common in women positive for HPV16/18, supporting their higher risk classification. Colposcopy referral rates were higher than during primary cytology-based testing, as predicted by clinical trial and modelling data. The prevalence of HPV was much higher in non-screening than in primary screening samples. Our findings indicate the renewed program is performing as expected during the initial HPV screening round.

Transforming activity of an oncoprotein-encoding circular RNA from human papillomavirus

Single-stranded circular RNAs (circRNAs), generated through ‘backsplicing’, occur more extensively than initially anticipated. The possible functions of the vast majority of circRNAs remain unknown. Virus-derived circRNAs have recently been described in gamma-herpesviruses. We report that oncogenic human papillomaviruses (HPVs) generate circRNAs, some of which encompass the E7 oncogene (circE7). HPV16 circE7 is detectable by both inverse RT-PCR and northern blotting of HPV16-transformed cells. CircE7 is N6-methyladenosine (m6A) modified, preferentially localized to the cytoplasm, associated with polysomes, and translated to produce E7 oncoprotein. Specific disruption of circE7 in CaSki cervical carcinoma cells reduces E7 protein levels and inhibits cancer cell growth both in vitro and in tumor xenografts. CircE7 is present in TCGA RNA-Seq data from HPV-positive cancers and in cell lines with only episomal HPVs. These results provide evidence that virus-derived, protein-encoding circular RNAs are biologically functional and linked to the transforming properties of some HPV.

Identification and characterization of novel human papillomaviruses in oral rinse samples from oral cavity and oropharyngeal cancer patients

ObjectivesThe objectives of this study were to: I) discover novel human papillomaviruses (HPVs) using next generation sequencing (NGS) technology in oral rinse samples collected from oral cavity cancer (OCC) and oropharyngeal cancer (OPC) patients; II) determine the prevalence of novel HPVs in archived OCC and OPC tissue samples; and III) examine the frequency of novel oncogenic HPVs in cancer and non-cancer oral rinse samples using real-time PCR. MethodsOral rinse samples were collected from 100 head and neck cancer patients, and 110 healthy individuals. NGS techniques were used to detect novel HPVs. ResultsThree potentially new types of HPV were discovered. Novel virus (NV) 14.4 was closely related to HPV76 with an 89% homology and is a member of the genus Beta-papillomavirus (β-PV); NV69.1 was distantly related to the genus Alpha-papillomavirus (α-PV), and NV95 was closely related to HPV147 with a 65–77% homology and is part of the genus Gamma-papillomavirus (γ-PV). In archived oral tissue samples, NV14.4 was detected in a single patient with OCC. Of the oral rinse samples, NV69.1 was more prevalent than the other two NVs. ConclusionsOur results demonstrated that there are novel HPVs present in oral rinse samples that may be associated with OCC and OPC. These novel HPVs can be identified and characterized using NGS techniques.

The E6/E7 oncogenes of human papilloma virus and estradiol regulate hedgehog signaling activity in a murine model of cervical cancer

Human papilloma virus oncogenes and estradiol are major etiologic factors associated with cervical cancer. In order to understand the mechanism by which these two factors promote carcinogenesis, the role of the Hedgehog (Hh) signaling pathway was evaluated during the normal growth of cervical epithelium and in the presence of E6/E7 oncogenes and exogenous estradiol. Hh signaling activity was determined in live animals (i.e., Gli-Luc reporter levels) during the estrous cycle and was found to be higher in the cervical area during the major growth phases, proestrus-estrus, in comparison to the diestrus phase. The same pattern was observed in transgenic mice expressing the E6/E7 oncogenes, though with notably higher levels than in control mice. Adding estradiol also markedly increased Gli activity in the cervix and the skin. In agreement with the correlation between high bioluminescence and tissue growth in different context, cervical cell proliferation was reduced upon Hh signaling inhibition in mice. Treatment with itraconazole, a putative novel Hh inhibitor, at an early stage of cervical carcinogenesis, did not decrease Hh signaling but it did reduce growth. Therefore, Hh signaling likely contributes to cervical carcinogenesis and itraconazole is effective to reduce growth but by a mechanism involving additional signaling pathways.

ADAM17-dependent signaling is required for oncogenic human papillomavirus entry platform assembly.

Oncogenic human papillomaviruses (HPV) are small DNA viruses that infect keratinocytes. After HPV binding to cell surface receptors, a cascade of molecular interactions mediates the infectious cellular internalization of virus particles. Aside from the virus itself, important molecular players involved in virus entry include the tetraspanin CD151 and the epidermal growth factor receptor (EGFR). To date, it is unknown how these components are coordinated in space and time. Here, we studied plasma membrane dynamics of CD151 and EGFR and the HPV16 capsid during the early phase of infection. We find that the proteinase ADAM17 activates the extracellular signal-regulated kinases (ERK1/2) pathway by the shedding of growth factors which triggers the formation of an endocytic entry platform. Infectious endocytic entry platforms carrying virus particles consist of two-fold larger CD151 domains containing the EGFR. Our finding clearly dissects initial virus binding from ADAM17-dependent assembly of a HPV/CD151/EGFR entry platform.

Protamine sulfate may prevent infections by pathogens that require heparan sulfate proteoglycan interactions, including high- and low-risk Human Papillomaviruses and Chlamydia trachomatis..

e13065 Background: Human papillomaviruses (HPVs) are the most common pathogens of the reproductive tract with 80% of the population acquiring an infection at least once in their lifetime. Globally, high-risk (oncogenic) HPVs cause 630,000 new cancer cases per year and are responsible for 99% of cervical cancers. Regardless of available screening and preventive measures, cervical cancer is the fourth most common malignancy in women worldwide causing more than 445,000 new cases and 270,000 deaths annually. Like many pathogens of the reproductive tract, initiation of HPV infections require attachment to negatively-charged heparan sulfate proteoglycans (HSPG) present in the extracellular matrix and plasma membrane of host cells. To better define the role of HSPGs in HPV infections, we used protamine sulfate (PrS), a polycationic peptide that is FDA approved to neutralize heparin. Structural similarities between HSPGs and heparin allow PrS to bind HSPGs preventing HPV-HSPG interactions and infection. In order to further evaluate proof of concept for PrS we expanded our investigation to Chlamydia trachomatis, another genital tract pathogen whose mechanism of infection has been reported to rely on HSPGs. Methods: High and low risk HPV viruses were used in prophylactic and post exposure cell-based assays and a preclinical prophylactic mouse vaginal challenge model to evaluate the effects of PrS on infection. Chlamydia trachomatis serovar L2 was also used in prophylactic cell-based assays to evaluate the effects of PrS on infection. Results: A single dose prophylactic application of PrS reduced infection by high- and low-risk HPV genotypes by up to 95% in vitro (p-value &lt; 0.001) in a dose response manner and 60% in vivo (p-value 0.05). In addition, post-HPV exposure PrS treatment significantly decreased infection. PrS showed the greatest effectiveness in the first two hours after HPV exposure. In line with our data on HPV, Chlamydia trachomatis infection showed a statistically significant decrease in cells pretreated with PrS (p-value 0.05). Conclusions: Inhibition of attachment by PrS presents a unique opportunity to provide a new cheap prophylactic modality for HPV infection, which would reduce cervical cancer global burden.

Comparison of HPV detection in HIV-infected and HIV-uninfected Kenyan women with or without cervical dysplasia.

e17015 Background: Cervical cancer, a malignancy caused by human papillomavirus (HPV) infection, is the most common malignancy in women living in sub-Saharan African countries including Kenya. HIV co-infection accelerates the natural course of cervical cancer. To determine the specific HPV type distribution in HIV-infected women compared to HIV-uninfected women, with and without evidence of cervical dysplasia. Methods: Demographic information, behavioral data, and a cervical swab were collected from women 18 and 45 years of age, HIV-infected or HIV-uninfected, who presented for cervical cancer screening at Moi Referral and Teaching Hospital in Eldoret, Kenya. Women were triaged based on the presence or absence of cervical dysplasia. HPV testing was performed using the Roche Linear Array Assay. Results were compared between women with or without HIV co-infection and between those with or without cervical dysplasia, using Chi-square tests or Fisher’s exact tests. Results: 223 women had normal VIAs. All had HPV testing, 221 had valid results: 115 HIV-infected women (mean age 37 years) and 106 HIV-uninfected (mean age 33 years). 175 women had abnormal VIAs. 143 women had HPV testing performed, 140 had valid results: 70 HIV-infected women (mean age 38.5 years) and 70 HIV-uninfected (mean age 31.3 years). Greater than 90% of all HIV-infected women in both projects were receiving anti-retroviral therapy at enrollment. HPV of any type was detected in 48% of all women with normal VIA vs. 61% of women with abnormal VIA (P = 0.018). High risk (HR)-HPV was detected in 38% of all women with normal VIA vs. 51% of all women with abnormal VIA (P = 0.012). HIV-uninfected women with normal VIA had significantly lower detection of all HPV (P = 0.026), high risk-HPV (P = 0.018), IARC high risk-HPV (P = 0.047), A9 types (P = 0.050), and individual types HPV 16 (P = 0.0274), HPV 18 (P = 0.007), and HPV 51 (P = 0.009) than HIV-uninfected women with abnormal VIA. Among HIV-infected women, there was no difference in detection of any group of HPV types or individual types with respect to VIA results. Conclusions: HIV-uninfected women without cervical dysplasia had lower detection of oncogenic HPV than HIV-uninfected women with dysplasia. In contrast, HPV detection did not differ among HIV-infected women between those with or without cervical dysplasia. In addition, VIA appears to lack specificity for HPV-associated cervical dysplasia, as 39% of women with abnormal VIA examinations did not have any HPV detected, and 49% of women with abnormal VIA examinations did not have any HR-HPV detected.

10 years of UK NEQAS digital morphology in haematology

Assess oral gargle-tumor human papillomavirus (HPV) agreement among oropharyngeal squamous cell carcinoma (OPSCC) cases by several disease characteristics.171 treatment naïve OPSCC were enrolled 2014–2017. Tumors were categorized as early or late disease with early disease defined as T1-2 with no nodal involvement or at most a single ipsilateral positive node <3 cm. Oral gargle samples were obtained via a 30-second rinse and gargle. The RHA Kit HPV SP10-LiPA25 was utilized for HPV genotyping of tumor (FFPE) and oral gargle specimens. Sensitivity, specificity, positive and negative predictive value, percent agreement, and 95% exact binomial confidence intervals were estimated. Multivariable logistic regression models were fit to predict agreement.83.0% and 93.0% of oral gargle and tumor specimens were HPV positive. Oral gargle-tumor agreement for any oncogenic HPV type and HPV 16 was 73.7%. High oncogenic HPV oral gargle-tumor agreement was observed for late disease presentation, p16 positive cases, and tumors at the tonsils (74.5–80.8%). Similar trends were observed for HPV 16. Agreement for any oncogenic HPV and HPV 16 was significantly higher for late vs. early disease (77.9% vs 57.1%, p = 0.01). Oral gargle-tumor oncogenic HPV and HPV 16 agreement was independently associated with age ≥50 years and late disease presentation.Overall, oral-tumor HPV agreement among OPSCC was relatively high. However, oral-tumor HPV agreement was significantly lower among younger cases and those diagnosed with earlier disease. Additional biomarkers are needed to improve oral HPV test characteristics to identify OPSCC early.

Dietary Polyphenols, Resveratrol and Pterostilbene Exhibit Antitumor Activity on an HPV E6-Positive Cervical Cancer Model: An in vitro and in vivo Analysis.

Human papilloma virus (HPV)-induced cervical cancer is one of the most frequent cancers in women residing in underdeveloped countries. Natural compounds like polyphenols continue to be of scientific interest as non-toxic effective alternative treatments. Our previous work showed the efficacy of two polyphenols, resveratrol, and pterostilbene on human HeLa cells. Here we explored the in vitro anti-cancer activity and in vivo anti-tumor potential of these two structurally similar compounds on HPV oncogene E6 and E7 positive murine TC1 cells. In vitro analysis confirmed the cytotoxic potential of both resveratrol and pterostilbene compounds with each having a low IC50 value and each showing the ability to downregulate viral oncogene E6. Further in vivo studies on TC1 tumors developing in mice indicated that treatment with either resveratrol or pterostilbene can significantly inhibit tumor development, with both compounds capable of downregulating E6 and VEGF tumor protein levels. Interestingly, the decrease in tumor size in pterostilbene was associated with tumor cell apoptosis, as indicated by an upregulation of activated caspase-3 whereas in resveratrol-treated mice it was accompanied by arrest of cell cycle, as indicated by a downregulation of PCNA. Thus, resveratrol and pterostilbene can serve as potential antineoplastic agents against HPV E6+ tumors and may suppress tumor growth via two different mechanisms.

Association of Immunosuppression and Human Immunodeficiency Virus (HIV) Viremia With Anal Cancer Risk in Persons Living With HIV in the United States and Canada.

People living with human immunodeficiency virus (HIV; PLWH) have a markedly elevated anal cancer risk, largely due to loss of immunoregulatory control of oncogenic human papillomavirus infection. To better understand anal cancer development and prevention, we determined whether recent, past, cumulative, or nadir/peak CD4+ T-cell count (CD4) and/or HIV-1 RNA level (HIV RNA) best predict anal cancer risk. We studied 102 777 PLWH during 1996-2014 from 21 cohorts participating in the North American AIDS Cohort Collaboration on Research and Design. Using demographics-adjusted, cohort-stratified Cox models, we assessed associations between anal cancer risk and various time-updated CD4 and HIV RNA measures, including cumulative and nadir/peak measures during prespecified moving time windows. We compared models using the Akaike information criterion. Cumulative and nadir/peak CD4 or HIV RNA measures from approximately 8.5 to 4.5 years in the past were generally better predictors for anal cancer risk than their corresponding more recent measures. However, the best model included CD4 nadir (ie, the lowest CD4) from approximately 8.5 years to 6 months in the past (hazard ratio [HR] for <50 vs ≥500 cells/µL, 13.4; 95% confidence interval [CI], 3.5-51.0) and proportion of time CD4 <200 cells/µL from approximately 8.5 to 4.5 years in the past (a cumulative measure; HR for 100% vs 0%, 3.1; 95% CI, 1.5-6.6). Our results are consistent with anal cancer promotion by severe, prolonged HIV-induced immunosuppression. Nadir and cumulative CD4 may represent useful markers for identifying PLWH at higher anal cancer risk.

PI3K/AKT/mTOR Signaling Regulates the Virus/Host Cell Crosstalk in HPV-Positive Cervical Cancer Cells.

Human papillomavirus (HPV)-induced cancers will remain a significant clinical challenge for decades. Thus, the development of novel treatment strategies is urgently required, which should benefit from improving our understanding of the mechanisms of HPV-induced cell transformation. This should also include analyses of hypoxic tumor cells, which represent a major problem for cancer therapy. Recent evidence indicates that the PI3K/AKT/mTOR network plays a key role for the virus/host cell crosstalk in both normoxic and hypoxic HPV-positive cancer cells. In normoxic cells, the efficacy of the senescence induction upon experimental E6/E7 repression depends on active mTORC1 signaling. Under hypoxia, however, HPV-positive cancer cells can evade senescence due to hypoxic impairment of mTORC1 signaling, albeit the cells strongly downregulate E6/E7. Hypoxic repression of E6/E7 is mediated by the AKT kinase, which is activated under hypoxia by its canonical upstream regulators mTORC2 and PI3K. This review highlights our current knowledge about the oxygen-dependent crosstalk of the PI3K/AKT/mTOR signaling circuit with the HPV oncogenes and the phenotypic state of the host cell. Moreover, since the PI3K/AKT/mTOR pathway is considered to be a promising target for anticancer therapy, we discuss clinical implications for the treatment of HPV-positive cervical and head and neck squamous cell carcinomas.

Association of HPV genotypes with external anogenital warts: a cross sectional study

BackgroundThis study was undertaken to determine the distribution of type-specific human papillomavirus (HPV) in external anogenital warts, and the correlation with clinical presentation of warts and demographic data of patients.MethodsGenital warts specimens were obtained from 129 men and 27 women attending a dermatology clinic, who had been advised surgical excision. The tissues were fixed and screened for HPV DNA by using real-time PCR. HPV genotype was determined by PCR-based sequencing.ResultsSixteen different HPV genotypes were detected, comprising 4 oncogenic HPV genotypes (16, 18, 33, 38), 2 low-risk HPV types (LR) (6, 81), HPV 9, and other types associated with common warts (1a, 2, 4, 7, 27b, 27, 57b, 57c, 65). Oncogenic HPV types were found in 34.62% of patients, LR HPV types in 14.4%, HPV 9 in 0.64%, and common warts type in 50.6%. The prevalence of HPV infection with a single type was 88.4, 9.0% for two types, and 2.6% for three types. Multiple logistic regression model showed that age, gender, nationality, number of warts, size of each wart, and positive history of wart in sexual partner, were not predictors of HPV type. However, patients with anogenital warts of one to six months duration were three times more likely to have oncogenic HPV infection compared to those with less than one month.ConclusionsThis study shows that oncogenic HPV types are detected in around 35% of patients with genital warts, and are prevalent in warts of one to six months duration.

Cellular immune responses against natural human papillomavirus infections among men in Kisumu, Kenya

Human papillomavirus (HPV) is associated with ano-genital and cervical cancer. Persistence of oncogenic HPV genotypes is a requirement for development and progression of malignancies. Although, >70% of women clear incident HPV infections, data on natural history and HPV immunology among men is limited. To evaluate cell-mediated immune responses to natural HPV infections among men, we assessed cytokine responses on PBMCs collected from men with persistent or cleared HPV. Men with HPV clearance and those with HPV persistence had increased odds (6-times and 3-times respectively) of mounting cytokine responses compared to HPV uninfected men. Th1 cytokines IFN-γ (5.1-fold) and IL-2 (4.2-fold) were significantly (p < 0.0001) upregulated among men with HPV clearance compared to HPV uninfected men. Among men with HPV clearance compared to those with persistent HPV infection, only IFN-γ (2.4–fold) and IL-2 (3.0–fold) were significantly (p < 0.0001) upregulated. Th1 cell-mediated cytokine response was associated with natural HPV clearance in men.

CGAS-STING responses are dampened in high-risk HPV type 16 positive head and neck squamous cell carcinoma cells

Head and neck cancers (HNCs) are a major health problem and a leading cause of morbidity and mortality worldwide. More than 90% of these tumours are head and neck squamous cell carcinomas (HNSCCs). Amongst the common risk factors for HNCs (tobacco and alcohol use), there is a strong association of human papillomavirus (HPV) with HNSCCs. HPV type 16 (HPV 16), the major high-risk HPV type, is most commonly associated with HPV-driven HNSCCs. The promiscuous nature of the major HPV oncogene, E7, allows its interaction with a myriad of host proteins including STING, a component of the viral DNA-sensing cyclic GMP-AMP synthase (cGAS) - stimulator of interferon genes (STING) machinery. Sensing of viral DNA by the cGAS-STING machinery results in a type I interferon (IFN)-mediated anti-viral response. Amelioration of IFN responses resulting from the direct blockade of STING by E7 was first demonstrated in high-risk HPV type 18 (HPV 18) positive (+) cervical squamous cell carcinoma (CESC) cells. However, the role of E7 from HPV 16 (HPV 16E7) in antagonising cGAS-STING responses have not been investigated, let alone in the context of HNSCCs. Here, we show that HPV 16E7+, but not HPV 16E7 negative (−), HNSCC cells respond poorly to cGAS-STING activation stimulus. We further confirm that this inhibition occurred via the highly conserved LXCXE motif in 16E7. This finding contributes to the better understanding of role of high-risk HPV E7 in blocking cGAS-STING pathway, especially in the context of HNSCCs.