Latent papillomavirus infections and their regulation

The human Papillomavirus twilight zone - Latency, immune control and subclinical infection

The incorporation of HPV DNA testing into cervical screening programs has shown that many HPV-positive women are cytologically normal, with HPV-positivity fluctuating throughout life. Such results suggest that papillomaviruses may persist in a latent state after disease clearance, with sporadic recurrence. It appears that virus latency represents a narrow slot in a wider spectrum of subclinical and possibly productive infections. Clinical studies, and animal model infection studies, suggested a key role for host immune surveillance in maintaining such asymptomatic infections, and although infections may also be cleared, most studies have used the term 'clearance' to describe a situation where the presence of HPV DNA falls below the clinical detection level. Given our knowledge of papillomavirus immune evasion strategies and the restricted pattern of viral gene expression required for 'basal cell' persistence, the term 'apparent clearance' and 'subclinical persistence' of infection may better summarise our understanding. Subclinical infection also encompasses the lag phase, which occurs between infection and lesion development. This is dependent on infection titre, with multifocal infections developing more rapidly to disease. These concepts can usefully influence patient management where HPV-positivity occurs sometime after the onset of sexual activity, and where vertical transmission is suspected despite a lag period.

Vaginal microecology and its role in human papillomavirus infection and human papillomavirus associated cervical lesions

The vaginal microecology comprises the vaginal microbiome, immune microenvironment, vaginal anatomy, and the cervicovaginal fluid, which is rich in metabolites, enzymes, and cytokines. Investigating its role in the female reproductive system holds paramount significance. The advent of next-generation sequencing enabled a more profound investigation into the structure of the vaginal microbial community in relation to the female reproductive system. Human papillomavirus infection is prevalent among women of reproductive age, and persistent oncogenic HPV infection is widely recognized as a factor associated with cervical cancer. Extensive previous research has demonstrated that dysbiosis of vaginal microbiota characterized by a reduction in Lactobacillus species, heightens susceptivity to HPV infection, consequently contributing to persistent HPV infection and the progression of cervical lesion. Likewise, HPV infection can exacerbate dysbiosis. This review aims to provide a comprehensive summary of current literatures and to elucidate potential mechanisms underlying the interaction between vaginal microecology and HPV infection, with the intention of offering valuable insights for future clinical interventions.

P16 expression and recurrent cervical intraepithelial neoplasia after cryotherapy among women living with HIV

Background

The expression of p16 protein, a surrogate marker for high-risk human papillomavirus (hrHPV), is associated with cervical dysplasia. We evaluated correlates of p16 expression at treatment for high-grade cervical lesions and its utility in predicting the recurrence of cervical intraepithelial lesions grade 2 or higher (CIN2+) following cryotherapy among women with HIV.

Methods

This is a subgroup analysis of women with HIV in Kenya with baseline cervical biopsy-confirmed CIN2+ who were randomized to receive cryotherapy and followed every six-months for two-years for biopsy-confirmed recurrence of CIN2+. P16 immunohistochemistry was performed on the baseline cervical biopsy with a positive result defined as strong abnormal nuclear expression in a continuous block segment of cells (at least 10-20 cells).

Results

Among the 200 women with CIN2+ randomized to cryotherapy, 160 (80%) had a baseline cervical biopsy specimen available, of whom 94 (59%) were p16-positive. p16 expression at baseline was associated with presence of any one of 14 hrHPV genotypes [Odds Ratio (OR) = 3.2; 95% Confidence Interval (CI), 1.03-9.78], multiple lifetime sexual partners (OR = 1.6; 95% CI, 1.03-2.54) and detectable plasma HIV viral load (>1,000 copies/mL; OR = 1.43; 95% CI, 1.01-2.03). Longer antiretroviral therapy duration (≥2 years) at baseline had lower odds of p16 expression (OR = 0.46; 95% CI, 0.24-0.87) than <2 years of antiretroviral therapy. Fifty-one women had CIN2+ recurrence over 2-years, of whom 33 (65%) were p16-positive at baseline. p16 was not associated with CIN2+ recurrence (Hazard Ratio = 1.35; 95% CI, 0.76-2.40).

Conclusion

In this population of women with HIV and CIN2+, 41% of lesions were p16 negative and baseline p16 expression did not predict recurrence of cervical neoplasia during two-year follow up.

Prophylactic HPV vaccines in patients with HPV-associated diseases and cancer

Individuals with human papillomavirus (HPV)-related disease remain at risk for subsequent HPV infection and related disease after treatment of specific lesions. Prophylactic HPV vaccines have shown benefits in preventing subsequent HPV-related disease when administered before or soon after treatment. Based on our understanding of the HPV life cycle and vaccine mechanism of action, prophylactic HPV vaccination is not expected to clear active persistent HPV infection or unresected HPV-associated dysplastic tissue remaining after surgery. However, vaccination may reasonably be expected to prevent new HPV infections caused by a different HPV type as well as re-infection with the same HPV type, whether from a new exposure to an infected partner or through autoinoculation from an adjacent or distant productively infected site. In this review, we describe the evidence for using prophylactic HPV vaccines in patients with HPV-associated disease before, during, or after treatment and discuss potential mechanisms by which individuals with HPV-associated disease may or may not benefit from prophylactic vaccines. We also consider how precise terminology relating to the use of prophylactic vaccines in this population is critical to avoid the incorrect implication that prophylactic vaccines have direct therapeutic potential, which would be counter to the vaccine's mechanism of action, as well as considered off-label. In other words, the observed effects occur through the known mechanism of action of prophylactic HPV vaccines, namely by preventing virus of the same or a different HPV type from infecting the patient after the procedure.

Viral Prevalence and Genomic Xenology in the Coevolution of HzNV-2 (Nudiviridae) with Host Helicoverpa zea (Lepidoptera: Noctuidae)

Insect viruses have been described from numerous lineages, yet patterns of genetic exchange and viral prevalence, which are essential to understanding host-virus coevolution, are rarely studied. In Helicoverpa zea, the virus HzNV-2 can cause deformity of male and female genitalia, resulting in sterility. Using ddPCR, we found that male H. zea with malformed genitalia (agonadal) contained high levels of HzNV-2 DNA, confirming previous work. HzNV-2 was found to be prevalent throughout the United States, at more than twice the rate of the baculovirus HaSNPV, and that it contained several host-acquired DNA sequences. HzNV-2 possesses four recently endogenized lepidopteran genes and several more distantly related genes, including one gene with a bacteria-like sequence found in both host and virus. Among the recently acquired genes is cytosolic serine hydroxymethyltransferase (cSHMT). In nearly all tested H. zea, cSHMT contained a 200 bp transposable element (TE) that was not found in cSHMT of the sister species H. armigera. No other virus has been found with host cSHMT, and the study of this shared copy, including possible interactions, may yield new insights into the function of this gene with possible applications to insect biological control, and gene editing.

Human Papillomavirus Intermittence and Risk Factors Associated With First Detections and Redetections in the Ludwig-McGill Cohort Study of Adult Women

BACKGROUND

We assessed the incidence and risk factors for first detection and redetection with the same human papillomavirus (HPV) genotype, and prevalence of cytological lesions during HPV redetections.

METHODS

The Ludwig-McGill cohort study followed women aged 18-60 years from São Paulo, Brazil in 1993-1997 for up to 10 years. Women provided cervical samples for cytology testing and HPV DNA testing at each visit. A redetection was defined as a recurring genotype-specific HPV positive result after 1 or more intervening negative visits. Predictors of genotype-specific redetection were assessed using adjusted hazard ratios (aHR) with Cox regression modeling.

RESULTS

In total, 2184 women contributed 2368 incident HPV genotype-specific first detections and 308 genotype-specific redetections over a median follow-up of 6.5 years. The cumulative incidence of redetection with the same genotype was 6.6% at 1 year and 14.8% at 5 years after the loss of positivity of the first detection. Neither age (aHR 0.90; 95% confidence interval [CI], .54-1.47 for ≥45 years vs < 25 years) nor new sexual partner acquisition (aHR 0.98; 95% CI, .70-1.35) were statistically associated with genotype-specific redetection. High-grade squamous intraepithelial lesion prevalence was similar during first HPV detections (2.9%) and redetection (3.2%).

CONCLUSIONS

Our findings suggest many HPV redetections were likely reactivations of latent recurring infections.

Cervical Health in Systemic Lupus Erythematosus

Objective

A health disparity exists for African American (AA) women with systemic lupus erythematosus (SLE) who have increased prevalence of human papilloma virus (HPV) infection and cervical neoplasia. We used a self-sampling brush to obtain cervical cells to assess cytology, HPV infection, and vaginal cytokine production in AA women with SLE.

Methods

Thirty AA women with SLE ages 18-50 years consented to participate. Clinical information was obtained by review of records and patient interviews, and surveys administered to assess cervical health history, knowledge of HPV, and satisfaction with the self-sampling brush. Vaginal samples were analyzed for cytology, HPV DNA and RNA, and vaginal cytokine RNA.

Results

Our cohort (mean 36.9, ±9.4 years) had moderate/severe SLE and were on immunosuppressives. The majority had history of abnormal pap smears (63%) with prevalent risk factors for HPV infection: multiple sex partners (9.5 ± 7), not vaccinated for HPV (83.3%), smoking (26.7%), and not using condoms (73.3%). Most were aware of HPV causing cervical cancer (70%) but were unaware of other HPV-related diseases. Most preferred self-sampling over traditional pap smear (80%). Abnormal cytology was detected in 13.3%. HPV DNA was detected in 70%, with half showing multiple types, and all showing active infection (+RNA). HPV-infected samples demonstrated RNA expression of multiple cytokines with no specific/ consistent pattern.

Conclusion

Our high-risk cohort lacked knowledge about HPV-related diseases and were not employing strategies to reduce their risk with vaccination and condoms. This study highlights the need for cervical health education, increased monitoring, and intervention in these high-risk women.

Detection of Five Types of HPV Genotypes Causing Anogenital Warts (Condyloma Acuminatum) Using PCR-Tm Analysis Technology

Objectives

Condyloma acuminatum (CA) is a common sexually transmitted disease caused by human papillomavirus (HPV) infection. We established a high-throughput, simple, low-cost, and accurate HPV-typing assay (polymerase chain reaction-melting temperature [PCR-Tm] analysis) to detect HPV in CA.

Materials and Methods

We detected 280 cervical scraping samples, including positive samples of HPV-6 (26), HPV-11 (12), HPV-16 (22), HPV-42 (18), HPV-43 (25), HPV-multiple (19), HPV- other type (58), and HPV-negative samples (100). All samples were compared by PCR-Tm analysis and a flow fluorescence hybridization assay. Sequencing was used to confirm the results of the PCR-Tm analysis.

Results

PCR-Tm analysis was specific for each genotype (HPV-6, HPV-11, HPV-16, HPV-42, and HPV-43). The sensitivity of the PCR-Tm analysis assay for each genotype was 10³, 10³, 10³, 10³, and 10² copies/reaction, respectively. Most of the 158 samples, including 58 HPV-other type positive and 100 HPV-negative samples tested by the flow fluorescence hybridization assay, were tested negative by PCR-Tm analysis. For the 122 remaining samples, 26 HPV-6, 12 HPV-11, 22 HPV-16, 18 HPV-42, 25 HPV-43, and 19 multiple HPV infections were detected through PCR-Tm analysis. In total, 25 HPV-6, 12 HPV-11, 21 HPV-16, 18 HPV-42, 25 HPV-43, and only 10 multiple HPV infections were detected by the flow fluorescence hybridization assay. The kappa coefficient for the analysis of PCR-Tm analysis and flow fluorescence hybridization assay was 0.940 (P < 0.0001), and the 95% confidence interval of the kappa coefficient was 90.3–97.7%.

Conclusion

PCR-Tm analysis enabled the detection of HPV-6, HPV-11, HPV-16, HPV-42, and HPV-43, including single and multiple infections.

Possible Reactivation of Latent Anal Human Papillomavirus Associated with Markers of Immune Dysfunction in Gay and Bisexual Men

BACKGROUND

It is unknown whether reactivation of human papillomavirus (HPV) after latency occurs in the anus. We measured incidence and predictors of incident anal HPV in sexually inactive gay and bisexual men (GBM) as a surrogate of HPV reactivation.

METHODS

The Study of the Prevention of Anal Cancer collected data on sexual behavior, anal cytology, HPV DNA, histology and HPV serology. HPV incidence during periods when zero sexual partners were reported in the last six months at both the current and previous annual visit ("no sexual activity") was analyzed by Cox regression using the Wei-Lin-Weissfeld method to determine univariable predictors.

RESULTS

Of 617 men enrolled, 525 had results for ≥2 visits, of whom 58 (11%) had ≥ one period of "no sexual activity". During sexually inactive periods, there were 29 incident high risk HPV infections in 20 men, which occurred more commonly in older men (Ptrend = 0.010), HIV-positive men (HR = 3.12; 95% CI, 0.91-16.65), longer duration of HIV (Ptrend = 0.028), history of AIDS defining illness (P = 0.010), lower current (P = 0.010) and nadir CD4 count (P = 0.014). For 18 of 29 infections with available results, 12 men remained type-specific HRHPV L1 seronegative. None were consistently seropositive. A new diagnosis of HSIL occurred in only two men, caused by an HPV type other than the incident type.

CONCLUSIONS

Our findings suggest that in sexually inactive GBM, anal HRHPV incidence is relatively common, and is associated with increasing age and immune dysfunction, a pattern consistent with HPV reactivation.

IMPACT

Reactivation of anal HPV may occur.

Impact of Human Papillomavirus on Wnt/Beta-Catenin Signaling in Morphological Inconspicuous Cervicovaginal Cells

INTRODUCTION

The aim of this study was to identify early changes in the Wnt/beta-catenin signaling pathway in high-risk human papillomavirus (HPV) infected cervicovaginal cells and to correlate these changes with cell proliferation, apoptosis, and autophagic processes.

METHODS

We evaluated 91 cervicovaginal smears of women with (n = 41) and without (n = 50) HPV-DNA. Smears were stained against beta-catenin, c-myc, secreted frizzled-related protein 4 (sFRP4), cleaved caspase-3, and the autophagy markers Beclin-1 and light chain 3B. In addition, sFRP-1, -2, -3, -4, -5 mRNA levels were determined by quantitative reverse transcription-PCR in primary keratinocytes and FaDu cells expressing HPV16-E6, -E7, or -E6E7.

RESULTS

Our data indicated that the Wnt/beta-catenin signaling is activated in HPV (+) cervicovaginal cells that can already be detected in cells with no obvious changes in cellular morphology (HPV [+]/cyto [-]). These cells also had significantly higher sFRP4 levels when compared to HPV-negative samples. In primary keratinocytes, sFRP4 was found to be absent and sFRP1 and sFRP2 to be repressed in the presence of HPV16-E6 and E7. Interestingly, sFRP4 is expressed in FaDu cells and can be upregulated in the presence of E6E7. Curiously, SFRP4 expression correlated with an increase in the level of autophagic markers in HPV (+)/cyto (-) smears.

CONCLUSION

In conclusion, the activation of the Wnt/beta-catenin signaling pathway and upregulation of sFRP4, paralleled by an activation of the autophagic pathway may represent predisposing cellular factors early after HPV infection which need to be further determined in larger study.

Human papilloma virus in the etiopathogenesis of allergic nasal polyposis: A prospective study

PURPOSE

To evaluate and compare the prevalence of high-risk HPV and low-risk HPV types in patients with chronic rhinosinusitis with nasal polyposis (CRSwNP) and healthy controls.

MATERIALS AND METHODS

A prospective cohort study was conducted in a tertiary care hospital on the patients of CRSwNP undergoing surgical management. All patients underwent preoperative endoscopic evaluation and radiological assessment using NCCT of the nose and paranasal sinuses. The severity of the disease was graded using the Lund-Mackay score on NCCT. All patients underwent endoscopic polypectomy and the sample of tissues was sent for HPV DNA detection using Hybrid Capture II® technique. The clinicopathological characteristics of HPV positive and negative patients were compared.

RESULTS

Sixty cases and 20 controls were included in the study. All controls were negative for HPV DNA. 27 patients (45%) had the presence of HPV DNA, out of which 23 had only LR-HPV and 1 had only HR-HPV types. Three patients had both HR-HPV and LR-HPV subtypes. There was a significant difference between the cases and controls for the presence of HPV DNA (p < 0.001). However, the patients with HPV-positive DNA in the nasal specimen did not differ significantly from HPV-negative patients in age, gender, or severity of the disease.

CONCLUSIONS

Human papillomaviruses may play a significant role in the etiopathogenesis of CRSwNP, however, do not impact the degree of sinus involvement.

Proportion of incident genital human papillomavirus detections not attributable to transmission and potentially attributable to latent infections: Implications for cervical cancer screening

BACKGROUND

Infections with human papillomaviruses (HPV) may enter a latent state, and eventually become reactivated following loss of immune control. It is unclear what proportion of incident HPV detections are reactivations of previous latent infections versus new transmissions.

METHODS

The HITCH cohort study prospectively followed young newly-formed heterosexual partners recruited between 2005-2011 in Montréal, Canada. We calculated the fraction of incident HPV detections non-attributable to sexual transmission risk factors with a Bayesian Markov model. Results are the median (2.5-97.5 th percentiles) of the estimated posterior distribution.

RESULTS

544 type-specific incident HPV detection events occurred in 849 participants; 33% of incident HPV detections occurred in participants whose HITCH partners were negative for that HPV type and who reported no other sex partners over follow-up. We estimate that 43% (38-48%) of all incident HPV detections in this population were not attributable to recent sexual transmission and might be potentially reactivation of latent infections.

CONCLUSIONS

A positive HPV test result in many cases may be a reactivated past infection, rather than a new infection from recent sexual behaviors or partner infidelity. The potential for reactivation of latent infections in previously HPV-negative women should be considered in the context of cervical cancer screening.

Human papillomaviruses: diversity, infection and host interactions

Human papillomaviruses (HPVs) are an ancient and highly successful group of viruses that have co-evolved with their host to replicate in specific anatomical niches of the stratified epithelia. They replicate persistently in dividing cells, hijack key host cellular processes to manipulate the cellular environment and escape immune detection, and produce virions in terminally differentiated cells that are shed from the host. Some HPVs cause benign, proliferative lesions on the skin and mucosa, and others are associated with the development of cancer. However, most HPVs cause infections that are asymptomatic and inapparent unless the immune system becomes compromised. To date, the genomes of almost 450 distinct HPV types have been isolated and sequenced. In this Review, I explore the diversity, evolution, infectious cycle, host interactions and disease association of HPVs.

Episome partitioning and symmetric cell divisions: Quantifying the role of random events in the persistence of HPV infections

Human Papillomaviruses (HPV) are one of the most prevalent sexually transmitted infections (STI) and the most oncogenic viruses known to humans. The vast majority of HPV infections clear in less than 3 years, but the underlying mechanisms, especially the involvement of the immune response, are still poorly known. Building on earlier work stressing the importance of randomness in the type of cell divisions in the clearance of HPV infection, we develop a stochastic mathematical model of HPV dynamics that combines the previous aspect with an explicit description of the intracellular level. We show that the random partitioning of virus episomes upon stem cell division and the occurrence of symmetric divisions dramatically affect viral persistence. These results call for more detailed within-host studies to better understand the relative importance of stochasticity and immunity in HPV infection clearance.

Every year, infections by Human Papillomaviruses (HPV) are responsible for a large share of infectious cancers. The prevalence of HPVs is very high, which makes it a major public health issue. Fortunately, most HPV infections (80 to 90%) are cleared naturally within three years. Among the few that persist into chronic infections, the majority also naturally regress. Hence for a given HPV infection, the risk of progression towards cancerous status is low. The immune response is often invoked to explain HPV clearance in non-persisting infections, but many uncertainties remain. Besides immunity, randomness was also suggested to play an important role. Here, we examine how random events occurring during the life cycle of the virus could alter the persistence of the virus inside the host. We develop a mechanistic model that explicitly follows the dynamic of viral copies inside host cells, as well as the dynamics of the epithelium. In our model, infection extinction occurs when all viral copies end up in differentiated cells and migrate towards the surface. This can happen upon cell division during the random allocation of the episomes (i.e. independent circular DNA copies of the viral genome) or when a stem cell divides symmetrically to generate two differentiated cells. We find that the combination of these random events drastically affects infection persistence. More generally, the importance of random fluctuations could match that of immunity and calls for further studies at the within-host and the epidemiological level.

The Impact of Laryngopharyngeal Reflux on Occurrence and Clinical Course of Recurrent Respiratory Papillomatosis

OBJECTIVES/HYPOTHESIS

Laryngopharyngeal reflux (LPR) has been proposed both as a trigger for recurrent respiratory papillomatosis (RRP) onset and as a factor favoring an aggressive clinical course.

STUDY DESIGN

In this prospective study, 106 participants were recruited within a period of 24 months at the Department of Otorhinolaryngology and Cervicofacial Surgery, University Medical Centre Ljubljana.

METHODS

This study compared a group of RRP patients (N = 36) with a group of LPR patients (N = 28) and a group of healthy participants (N = 42) based on Reflux Symptom Index (RSI), Reflux Finding Scores (RFS), and saliva analyses (pH, pepsin concentration, bile acid concentration, and pepsin enzymatic activity).

RESULTS

The RRP group compared to the LPR group showed a statistically significant difference only in RSI and RFS scores, while the RRP group compared to healthy controls showed significantly higher values in all tested parameters (RSI score, RFS, saliva pH, pepsin concentration, bile acids concentration, pepsin enzymatic activity).

CONCLUSIONS

LPR is common in RRP patients and significantly more prevalent compared to healthy controls. Our results show that saliva analyses are a better office-based tool than RSI questionnaires and RFS scores for diagnosing LPR in RRP patients.

LEVEL OF EVIDENCE

Level 3 Laryngoscope, 2021.

Prevalence and Risk Factors of Infection with High Risk Human Papilloma Viruses among HIV-Positive Women with Clinical Manifestations of Tuberculosis in a Middle-Income Country

Women living with HIV-1 are at high risk of infection with human papillomavirus of high carcinogenic risk (HR HPVs). M. tuberculosis (TB) promotes HPV infection and increases the risk to develop HPV-associated cancer. Our knowledge of persisting HR HPVs genotypes, and of the factors promoting HR HPV infection in people living with HIV-1 with clinical TB manifestations is sparse. Here, we analyzed 58 women living with HIV-1 with clinical TB manifestations (WLWH with TB) followed up in specialized centers in Russia, a middle income country endemic for HIV-1 and TB, for the presence in cervical smears of DNA of twelve HR HPV genotypes. DNA encoding HPV16 E5, E6/E7 was sequenced. Sociodemographic data of patients was collected by questionnaire. All women were at C2-C3 stages of HIV-infection (by CDC). The majority were over 30 years old, had secondary education, were unemployed, had sexual partners, experienced 2–3 pregnancies and at least one abortion, and were smokers. The most prevalent was HPV16 detected in the cervical smears of 38% of study participants. Altogether 34.5% of study participants were positive for HR HPV types other than HPV16; however, but none of these types was seen in more than 7% of tested samples. Altogether, 20.7% of study participants were positive for several HR HPV types. Infections with HPVs other than HPV16 were common among WLWH with generalized TB receiving combined ART/TB-therapy, and associated with their ability to work, indirectly reflecting both their health and lifestyle. The overall prevalence of HR HPVs was associated with sexual activity of women reflected by the number of pregnancies, and of HPV 16, with young age; none was associated to CD4+-counts, route of HIV-infection, duration of life with HIV, forms of TB-infection, or duration of ART, characterizing the immune status. Thus, WLWH with TB—especially young—were predisposed to infection with HPV16, advancing it as a basis for a therapeutic HPV vaccine. Phylogenetic analysis of HPV16 E5, E6/E7 DNA revealed no common ancestry; sequences were similar to those of the European and American HPV16 strains, indicating that HPV vaccine for WLWH could be the same as HPV16 vaccines developed for the general population. Sociodemographic and health correlates of HR HPV prevalence in WLWH deserve further analysis to develop criteria/recommendations for prophylactic catch-up and therapeutic HPV vaccination of this highly susceptible and vulnerable population group.

ICOSL in host defense at epithelial barriers: lessons from ICOSLG deficiency

Autosomal recessive mutations in Inducible T Cell Costimulator Ligand (ICOSLG) result in a combined immunodeficiency syndrome of humans, saliently marked by recurrent respiratory tract infections and significant disease with DNA-based viruses at epithelial barriers, including human papillomavirus (HPV). These features are also seen in persons with loss of function of the complementary gene, ICOS. The infection phenotypes associated with these natural experiments disclose a critical role of the corresponding proteins, ICOSL and ICOS, in human immunity at mucocutaneous barriers. Here, we review the syndromes of ICOSL and ICOS deficiency and explore the mechanisms by which the ICOSL:ICOS axis mediates epithelial host defenses.

Correlation of the ALA-PDT Treatment Efficacy and the HPV Genotype Profile of Genital Warts after Cryotherapy Failure and Podophyllotoxin Therapy in Male Patients

Background: Genital warts are the manifestation of the human papillomavirus (HPV) infection, which may last for weeks or months before the clinical presentation. The primary aim of the study was the correlation of the DNA HPV genotypes eradication with the treatment response in male patients with persistent genital warts. Methods: Twenty-one male patients (age range: 22–58) after failure of cryotherapy and podophyllotoxin treatment were enrolled in the study. Genetic tests (Real Time - PCR method) analyzed the presence of DNA-HPV before and 6 months after four sessions (4 weeks apart) of photodynamic therapy with 5-aminolaevulinic acid (ALA-PDT). The treatment efficacy was evaluated before each PDT session and at the end of the study. Results: The single HPV DNA type was present in 15/21 of the patients (13/15 HPV6). The high-risk HPV types were found in 8/21 subjects, of which 6/8 had several types. Six months after four sessions of PDT, complete response was found in 16/21 (76.19%; p = 0.0007) of patients, and DNA HPV clearance was found in 66.67% (p = 0.03). The eradication rate differed among patients with primary low-risk and high-risk HPV types—76.92% (10/13; p = 0.0003) and 50% (4/8; p = 0.05) respectively. Conclusion: ALA-PDT is an effective treatment even after the failure of previous modalities. The persistence of clinical lesions and high oncological risk HPV types should be an indication for treatment prolongation.

CDH1 and SNAI1 are regulated by E7 from human papillomavirus types 16 and 18

A common characteristic of cancer types associated with viruses is the dysregulated expression of the CDH1 gene, which encodes E‑cadherin, in general by activation of DNA methyltransferases (Dnmts). In cervical cancer, E7 protein from high risk human papillomaviruses (HPVs) has been demonstrated to interact with Dnmt1 and histone deacetylase type 1 (HDAC1). The present study proposed that E7 may regulate the expression of CDH1 through two pathways: i) Epigenetic, including DNA methylation; and ii) Epigenetic‑independent, including the induction of negative regulators of CDH1 expression, such as Snail family transcriptional repressor Snai1 and Snai2. To test this hypothesis, HPV16‑ and HPV18‑positive cell lines were used to determine the methylation pattern of the CDH1 promoter and its expression in association with its negative regulators. Different methylation frequencies were identified in the CDH1 promoter in HeLa (88.24%) compared with SiHa (17.65%) and Ca Ski (0%) cell lines. Significant differences in the expression of SNAI1 were observed between these cell lines, and an inverse association was identified between the expression levels of SNAI1 and CDH1. In addition, suppressing E7 not only increased the expression of CDH1, but notably decreased the expression of SNAI1 and modified the methylation pattern of the CDH1 promoter. These results suggested that the expression of CDH1 was dependent on the expression of SNAI1 and was inversely associated with the expression of E7. The present results indicated that E7 from HPV16/18 regulated the expression of CDH1 by the two following pathways in which Snai1 is involved: i) Hypermethylation of the CDH1 promoter region and increasing expression of SNAI1, as observed in HeLa; and ii) Hypomethylation of the CDH1 promoter region and expression of SNAI1, as observed in SiHa. Therefore, the suppression of CDH1 and expression of SNAI1 may be considered to be biomarkers of metastasis in uterine cervical cancer.

Conversion of Sox2-dependent Merkel cell carcinoma to a differentiated neuron-like phenotype by T antigen inhibition

Normal cells can be transformed into cancer cells by viral oncogenes. Reversion of a viral human cancer cell, however, into a differentiated cell by viral oncogene inhibition has not been described. Merkel cell carcinoma (MCC) is a neuroendocrine cancer caused by Merkel cell polyomavirus (MCV) that encodes a T antigen oncogene. When MCV⁺ MCC cells with T antigen knockdown are cocultured with keratinocytes, the MCC phenotype converts to a differentiated neuronal phenotype and loses Merkel cell factor Sox2 and Atoh1 expression. MCV large T activates Sox2 and Atoh1 by its ability to inhibit retinoblastoma. Sox2 inhibition similarly induced this phenotypic conversion of MCC. These findings suggest that MCV induces cancer by dysregulating embryonic Merkel cell differentiation pathways.

Viral cancers show oncogene addiction to viral oncoproteins, which are required for survival and proliferation of the dedifferentiated cancer cell. Human Merkel cell carcinomas (MCCs) that harbor a clonally integrated Merkel cell polyomavirus (MCV) genome have low mutation burden and require viral T antigen expression for tumor growth. Here, we showed that MCV⁺ MCC cells cocultured with keratinocytes undergo neuron-like differentiation with neurite outgrowth, secretory vesicle accumulation, and the generation of sodium-dependent action potentials, hallmarks of a neuronal cell lineage. Cocultured keratinocytes are essential for induction of the neuronal phenotype. Keratinocyte-conditioned medium was insufficient to induce this phenotype. Single-cell RNA sequencing revealed that T antigen knockdown inhibited cell cycle gene expression and reduced expression of key Merkel cell lineage/MCC marker genes, including HES6, SOX2, ATOH1, and KRT20. Of these, T antigen knockdown directly inhibited Sox2 and Atoh1 expression. MCV large T up-regulated Sox2 through its retinoblastoma protein-inhibition domain, which in turn activated Atoh1 expression. The knockdown of Sox2 in MCV⁺ MCCs mimicked T antigen knockdown by inducing MCC cell growth arrest and neuron-like differentiation. These results show Sox2-dependent conversion of an undifferentiated, aggressive cancer cell to a differentiated neuron-like phenotype and suggest that the ontology of MCC arises from a neuronal cell precursor.

Lower Genital Tract Precancer and Cancer in Hematopoietic Cell Transplant Survivors and the Role of HPV: A Systematic Review and Future Perspectives

Female recipients of hematopoietic cell transplant (HCT) may develop lower genital tract (LGT) dysplasia or new malignancies. A comprehensive systematic review to delineate the occurrence and risk factors for post-HCT LGT precancer and cancer in women was conducted via electronic search of the Cochrane Library, PubMed, Embase, Wiley Online Library, from 1990 to 2018. All studies on the risk, presentation, or incidence of LGT (cervix, vulva, vagina) precancer or cancer post-HCT were included. Reviews, case reports, meta-analysis, book chapters, and studies without the relevant clinical outcomes were excluded. Post-HCT incidence and risk factors for developing LGT precancer or cancer were assessed and determined. Twenty-two out of the original 344 studies met the selection criteria. The risk of LGT cancers in allo-HCT recipients was found to be significantly higher than in the general population, with the standardized incidence ratios of 1.5–48 for cervical cancer and from 19 to 287 for dysplasia. Our review portrays an increased risk of premalignant and malignant neoplasms of female LGT, which have an incompletely described epidemiology and outcomes. Similar to other immunocompromised states, HCT recipients require specific cervical screening guidelines and can greatly benefit from HPV vaccinations. However, there is a lack of prospective data regarding optimum cervical screening in HCT recipients and limited programs offer HPV vaccinations worldwide.

One-step detection of human papilloma viral infection using quantum dot-nucleotide interaction specificity

Due to the close relationship between carcinogenesis and human papillomavirus (HPV), and since they are transmitted via huge number of asymptomatic carriers, the detection of HPV is really needed to reduce the risk of developing cancer. According to the best of our knowledge, our study provides the very first method for one-step detection of viral infection and if it has initiated the subsequent cancer proliferation. The proposed novel nanosystem consists of magnetic glass particles (MGPs), which were attached with DNA probe on their surface to hybridize with target DNAs. The MGP-probe-DNA hybrid was finally conjugated with CdTe/ZnSe core/shell quantum dots (QDs). The proposed detection system is based on a novel mechanism in which the MGPs separate out the target DNAs from different biological samples using external magnetic field for better and clear detection and the QDs give different fluorescent maxima for different target DNAs due to their ability to interact differently with different nucleotides. Firstly, the method was optimized using HPV genes cloned into synthetic plasmids. Then it was applied directly on the samples from normal and cancerous cells. After that, the real hospital samples of head and neck squamous cell carcinoma (HNSCC) with or without the infection of HPV were also analyzed. Our novel nano-system is proved successful in detecting and distinguishing between the patients suffering by HPV infection with or without subsequent cancer having detection limit estimated as 1.0 x 10⁹ (GEq/mL). The proposed methodology is faster and cost-effective, which can be applied at the clinical level to help the doctors to decide the strategy of medication that may save the life of the patients with an early treatment.

HPV Infections in Heterosexual Couples: Mechanisms and Covariates of Virus Transmission

Sexual intercourse is regarded as the primary route of human papillomavirus (HPV) transmission. Reported rates of the genotype-specific genital concordance of HPV infection among heterosexual partners vary. Most studies have evaluated only male/female genital transmission, but lately, the oral region has gained interest because of a rising trend of HPV-associated oropharyngeal cancer. Risk factors for type-specific concordance have been reported as an increasing number of younger couples, persistent HPV infection, higher frequency of sexual intercourse, rising number of spouse's lifetime sexual partners, and sexual relations with prostitutes. However, the concordance of the same genital HPV genotype does not absolutely mean that it has been transmitted by the current partner. There are also other possible non-sexual transmission routes. The detected HPV infection may also be a reactivation of a previous infection. The high complexity of HPV transmission dynamics within an individual him-/herself as well as within sexual couples is discussed in this article.

Human papillomavirus DNA detection-guided ALA-photodynamic therapy for anogenital condyloma acuminata: A report of two cases

5-aminolevulinic acid (ALA) mediated photodynamic therapy (PDT) is a highly effective, safe, and promising treatment for human papillomavirus (HPV)-induced anogenital condyloma acuminata (CA). Specific HPV subtypes are responsible for the pathogenesis of CA and dynamic changes in viral loads may reflect the efficiency of PDT. Here we present two cases of anogenital CA successfully treated by ALA-PDT under the guidance of HPV DNA detection including genotype identification and viral load measurement, which provided clues for unexpected intra-anal infection. Both of these male patients were free of detectable HPV at the end of the treatment and no recurrence was observed after 1 year. We conclude that the HPV DNA detection can accurately guide ALA-PDT, indicate unnoticed lesions, as well as improve and evaluate the efficiency.

Oral fibropapillomatosis and epidermal hyperplasia of the lip in newborn lambs associated with bovine Deltapapillomavirus

Congenital fibropapillomatosis of the gingiva and oral mucosa and epidermal hyperplasia of the lip are described, for the first time, in two newborn lambs. Expression of the E5 oncoprotein of bovine deltapapillomavirus types 2 (BPV-2) and -13 (BPV-13) was detected in both fibropapillomas and the hyperplastic epidermal cells suggesting the BPV infection was the cause of the proliferative lesions. No DNA sequences of BPV-1 and BPV-14 were detected. Both BPV-2 and BPV-13 DNA were also amplified from peripheral blood mononuclear cells (PBMCs) of the newborn lambs’ dams. The concordance between BPV genotypes detected in the blood of dam and the oral and skin pathological samples of their offspring suggests that a vertical hematogeneous transmission was most likely source of BPV infection. Immunoblotting revealed the presence of E5 dimers allowing the viral protein to be biologically active. E5 dimers bind and activate the platelet derived growth factor β receptor (PDGFβR), a major molecular mechanism contributing to disease. The detection of E5 protein within the proliferating cells therefore adds further evidence that the BPV infection was the cause of the proliferative lesions seen in these lambs. This is the first evidence of vertical transmission of BPVs in sheep resulting in a clinical disease.

Treatment of latent or subclinical Genital HPV Infection with 5-aminolevulinic acid-based photodynamic therapy

BACKGROUND

Genital HPV infections are widely prevalent. HPV can persist and be transmitted to partners even after warts are gone. The HPV genotype and viral load assay can reveal whether infections are persistent or latent, and it can serve as a predictor of infection clearance. Although numerous studies have demonstrated that photodynamic therapy (PDT) is effective against condyloma acuminata, there is no data on its effects on latent, persistent infections.

METHODS

A total of 20 patients with latent or subclinical HPV infection were evaluated. At each patient visit, polymerase chain reaction was used to identify HPV genotypes and measure the viral loads, which reflect the status of HPV infection. We administered 5-aminolevulinic acid (ALA)-based PDT weekly for patients with active infections, while no treatment was administered to patients with regressing infections.

RESULTS

PDT treatment can effectively eliminate HPV, significantly reducing viral loads after three rounds of treatment (p < 0.001). The rate of negative HPV DNA test results was higher in patients with latent or subclinical infections than in patients with genital warts after one round of PDT treatment.

CONCLUSIONS

ALA-PDT can effectively eliminate latent or subclinical HPV infections. Additionally, our assay for identifying HPV genotypes and viral loads, which reflect the status of HPV infection, can accurately guide ALA-PDT treatment.

Evidence for chronic mechanical irritation as a causative factor in oral cancer: application of Bradford Hill criteria

Chronic mechanical irritation (CMI) of the oral mucosa has been proposed as a risk factor for oral cancer (OC), but the available evidence is limited and controversial. One of the main limitations is the lack of proper criteria to define and classify CMI. The objective of this narrative review is to apply the Bradford Hill causality criteria to assess such an association based on the published literature. The level of evidence is not conclusive, mainly due to methodological shortcomings. Hence, to systematize future CMI research, we recommend the following items should be included: a clear definition for CMI, ascertaining any temporal association, recording all types of CMI: dental, prosthetic, and functional. Finally, it is important to emphasize that studies dealing with risk factors for OC should not only be restricted to established factors such as tobacco, alcohol, and areca nut consumption but should also consider other factors including the patient’s dental condition. In this regard, CMI, tooth loss, periodontal disease, and many others could be included. The causality criteria set out by Bradford Hill could be used for studying different controversial risk factors for OC.

Redetection of human papillomavirus type 16 infections of the cervix in mid-adult life

PURPOSE

To assess whether HPV 16 originally detected in adolescent women can be redetected in adulthood.

METHODS

A convenience sample of 27 adult women with known HPV 16 detection during adolescence was assessed for HPV 16 redetection. A comparison of the long control region (LCR) DNA sequences was performed on some of the original and redetected HPV 16 isolates.

RESULTS

Median age at reenrollment was 27.5 years (interquartile range of 26.7-29.6). Reenrollment occurred six years on average after the original HPV 16 detection. Eleven of 27 women had HPV 16 redetected. Some of these HPV 16 infections had apparently cleared during adolescence. LCR sequencing was successful in paired isolates from 6 women; in 5 of 6 cases the redetected HPV 16 isolates were identical to those detected during adolescence, CONCLUSIONS: HPV 16 may be episodically detected in young women, even over long time periods. HPV 16 redetection with identical LCR sequences suggests low-level persistent infection rather than true clearance, although newly acquired infection with an identical HPV 16 isolate cannot be excluded. However, this study suggests that a new HPV 16-positive test in a clinical setting may not indicate a new infection.

Epstein-Barr Virus and Human Papillomaviruses Interactions and Their Roles in the Initiation of Epithelial-Mesenchymal Transition and Cancer Progression

Oncoviruses are implicated in around 20% of all human cancers including both solid and non-solid malignancies. Epstein–Barr virus (EBV) and human papillomaviruses (HPVs) are the most common oncoviruses worldwide. Currently, it is well established that onco-proteins of EBV (LMP1, LMP2A, and EBNA1) and high-risk HPVs (E5 and E6/E7) play an important role in the initiation and/or progression of several human carcinomas, including cervical, oral, and breast. More significantly, it has been recently pointed out that viral onco-proteins of EBV and high-risk HPVs can be co-present and consequently cooperate to initiate and/or amplify epithelial–mesenchymal transition (EMT), which is the hallmark of cancer progression and metastasis. This could occur by β-catenin, JAK/STAT/SRC, PI3k/Akt/mTOR, and/or RAS/MEK/ERK signaling pathways, which onco-proteins of EBV and HPVs share. This review presents the most recent advances related to EBV and high-risk HPVs onco-proteins interactions and their roles in the progression of human carcinomas especially oral and breast via the initiation of EMT.

Oncogenic human papillomaviruses

Human papillomaviruses (HPVs) are an ancient group of viruses with small, double-stranded DNA circular genomes. They are species-specific and have a strict tropism for mucosal and cutaneous stratified squamous epithelial surfaces of the host. A subset of these viruses has been demonstrated to be the causative agent of several human cancers. Here, we review the biology, natural history, evolution and cancer association of the oncogenic HPVs.This article is part of the themed issue 'Human oncogenic viruses'.

HIV-positive women have higher risk of human papilloma virus infection, precancerous lesions, and cervical cancer

OBJECTIVE

HIV-positive women have higher human papillomavirus (HPV) prevalence and cervical cancer incidence than HIV-negative women, partly because of HIV's modifying effect on HPV pathogenesis. We synthesized the literature on the impact of HIV on HPV natural history.

DESIGN

Systematic review and meta-analysis.

METHODS

We searched the literature for studies evaluating HPV acquisition and persistence or precancer progression by HIV status. Data on HPV natural history by HIV status, CD4 cell counts, viral load, and antiretroviral therapy (ART) were summarized using fixed effect models.

RESULTS

Overall, 38 of 1845 abstracts identified met inclusion criteria. HIV-positive women had higher HPV acquisition [relative risk (RRpooled) 2.64, 95% confidence interval (CI) 2.04-3.42] and lower HPV clearance (hazard ratiopooled 0.72, 95% CI 0.62-0.84) than HIV-negative women. HPV acquisition was higher with declining CD4 cell count and was lower in those virally suppressed on ART. HIV was associated with higher incidence of low-grade squamous intraepithelial lesions (LSIL; RRpooled 3.73, 95% CI 2.62-5.32) and high-grade squamous intraepithelial lesions (HSIL; hazard ratiopooled 1.32, 95% CI 1.10-1.58), largely because of increased HPV persistence. ART lowered progression from normal cytology to LSIL (hazard ratiopooled 0.65, 95% CI 0.52-0.82), but not HSIL. Cervical cancer incidence was associated with HIV positivity (RR 4.1, 95% CI 2.3-6.6), but not with ART.

CONCLUSION

HIV-positive women have higher risk of acquiring HPV, with risk inversely associated with CD4 cell count. ART lowered HPV acquisition, increased clearance, and reduced precancer progression, likely via immune reconstitution. Although some of our results are limited by small number of studies, our study can inform screening guidelines and mathematical modeling for cervical cancer prevention.

Low Rate of Cervical Cancer Screening among Women with Hematologic Malignancies after Stem Cell Transplant

Annual cervical cancer screening with Papanicolaou (Pap) and human papillomavirus (HPV) testing after stem cell transplant (SCT) is recommended, but the uptake is unknown. We aimed to determine the prevalence and predictors of cervical cancer screening in patients with hematologic malignancies. We searched MarketScan Commercial Claims database for women who underwent allogeneic or autologous SCT. The primary outcome was cervical cancer screening, defined as procedures or abnormal results for HPV and/or Pap testing according administrative codes within 2 years after SCT. A multivariable logistic regression model was fitted with cancer type, SCT year, age, geographic area, insurance plan, comorbidity, and presence of graft-versus-host disease (GVHD).The study included 1484 patients; 1048 patients (70.6%) had autologous and 436 (29.4%) allogeneic SCT. Mean age was 52.5 years. Overall, 660 patients (44.5%) had screening within 2 years after SCT, 214 (49.1%) with allogeneic SCT and 446 (42.6%) with autologous SCT (P = .02). In the allogeneic SCT group, patients with GVHD had a lower rate of screening than patients without GVHD (42.5% versus 55.4%, P < .01), and GVHD was associated with lower odds of screening (odds ratio, .50; 95% confidence interval, .32 to .79). In the autologous SCT group, patients with comorbid medical conditions had a lower rate of screening than patients without comorbidity (36.0% versus 45.7%, P < .01). In both allogeneic and autologous SCT groups older patients had lower odds of screening. Cervical cancer screening rates after SCT are low, particularly in patients with GVHD, who are at significant risk of second malignancies. Future work is needed to develop strategies to increase uptake.

Human papillomavirus E7 induces p63 expression to modulate DNA damage response

Cervical cancer is the third most common malignancy diagnosed in women worldwide. The major aetiological factor underlying the malignant transformation of cervical cells is the persistent infection with high-risk human papillomaviruses (HR-HPV), with more than 99% of cases expressing viral sequences. Here, we report a previously unknown mechanism driven by high-risk human papillomavirus E7 protein to modulate response to DNA damage in cervical cancer cells. Our data shows that HR-HPV E7 oncoprotein induces the transcription of the p53-family member p63, which modulates DNA damage response pathways, to facilitate repair of DNA damage. Based on our findings, we proposed a model, where HR-HPV could interfere with the sensitivity of transformed cells to radiation therapy by modulating DNA damage repair efficiency. Importantly, we have shown for the first time a critical role for p63 in response to DNA damage in cervical cancer cells.

Dermatologic manifestations among human immunodeficiency virus patients in Morocco and association with immune status

OBJECTIVE

The objective was to determine if the type and number of skin diseases can be clinical indicators of underlying immune status in HIV1 disease by estimating and correlating with the CD4 count and CDC stage.

MATERIALS AND METHODS

This was a retrospective cross-sectional descriptive study. All consecutive patients infected with HIV1 followed at the Dermatology Department of Rabat Military Hospital between January 2008 and January 2017 were studied for dermatological manifestations, CD4 count and CDC clinical stage.

RESULTS

A total of 170 patients with 304 dermatological manifestations were included. The most common dermatoses were fold dermatophytic infections (67%), genital warts (43%), herpes zoster (21%), xerosis (21%), and oral candidiasis (12%). The number of dermatologic manifestations was significantly greater in patients with CD4 count less than 200/mm³ or in stage C of the CDC classification. Five types of skin diseases (dermatophyte infections of the folds, genital warts, shingles, oral candidiasis, and seborrheic dermatitis) were significantly associated (P < 0.05) with CD4 count <200/mm³ . Seborrheic dermatitis was the only one skin disease significantly associated with AIDS stage. In multivariate analysis, genital warts (OR = 0.3, 95% CI 0.10-0.92) are independently associated with CD4 count less than 200 CD4/mm³ .

CONCLUSIONS

Skin manifestations not only act as markers but also reflect the underlying immune status. Seborrheic dermatitis and genital warts appear to be a marker of immune status, and seborrheic dermatitis appears to be associated with CDC stage C, especially in their chronic and severe forms.

Cervical HPV prevalence and genotype distribution in immunosuppressed Danish women

INTRODUCTION

Women receiving immunosuppressive treatment due to organ transplantation are at increased risk of Human papilloma virus (HPV)-related diseases, including cervical neoplasia. This pilot study aimed to describe the cervical HPV prevalence and genotype distribution in immunosuppressed Danish women.

MATERIAL AND METHODS

We included women who underwent renal (RTR) or bone marrow transplantation (BMTR) in 2009-2012 or 2014 at Aarhus University Hospital, Denmark. Women undergoing transplantation in 2009-2012 had one cervical cytology performed, whereas women undergoing transplantation in 2014 had three, one before and two after transplantation. The samples were examined for cytological abnormalities and tested for HPV using Cobas^® HPV Test and CLART^® HPV2 Test.

RESULTS

Of 94 eligible cases we included 60 RTR and BMTR. The overall prevalence of high-risk HPV was 15.0 [95% confidence interval (CI) 7.1-26.6] and the prevalence was higher among BMTR (29.4; 95% CI 10.3-56.0) than RTR (9.3%, 95% CI 2.6-22.1), although this was not statistically significant (p = 0.10). The distribution of high-risk HPV was broad, with HPV 45 as the most common genotype (3.3%). The prevalences of high-risk HPV types included in the bivalent/quadrivalent and the nonavalent vaccines were 1.7 and 8.3%, respectively. The prevalence of low-grade and high-grade cytological abnormalities was 6.7 and 5.0%, respectively.

CONCLUSIONS

Immunosuppressed women were infected with a broad range of high-risk HPV genotypes and the prevalence of cytological abnormalities was higher than found in previous studies of the general population. The nonavalent HPV vaccine will offer immunosuppressed individuals a greater protection against HPV-related diseases compared with the bivalent/quadrivalent HPV vaccines.

Dynamics of HPV viral loads reflect the treatment effect of photodynamic therapy in genital warts

BACKGROUND

Photodynamic therapy (PDT) has demonstrated good clinical cure rates and low recurrence rates in the treatment of genital warts. Human papillomavirus (HPV) genotypes and viral load assays can reflect the status of persistent or latent infection and serve as a predictor of infection clearance.

METHODS

Specimens from 41 patients with HPV infection were obtained, and the HPV genotypes and viral load were analyzed using real-time polymerase chain reaction (PCR) assays. Traditional treatment, such as radiofrequency, microwave, or surgical therapy, was used to remove the visible lesions, and then PDT treatment was performed every week. HPV DNA testing was performed at every patient visit and the frequency of PDT treatment was determined by changes in HPV viral loads.

RESULTS

HPV viral loads decreased significantly after PDT treatment. There were significant differences in HPV viral loads between pretherapy and three or six rounds of PDT treatment. Significant differences were also observed between single and multiple type HPV infection after six rounds of PDT treatment. Patients with single type HPV infection had significantly higher rates of negative HPV DNA test results, as compared with patients with multiple infections after six rounds of PDT treatment; however, there was no difference in recurrence rates between the two groups.

CONCLUSIONS

Dynamic monitoring of HPV genotypes and viral loads can be used to guide PDT treatment and indicate PDT treatment efficacy in eliminating HPV.

Molecular characterization, prevalence and clinical relevance of Phodopus sungorus papillomavirus type 1 (PsuPV1) naturally infecting Siberian hamsters (Phodopus sungorus)

Phodopus sungorus papillomavirus type 1 (PsuPV1), naturally infecting Siberian hamsters (Phodopus sungorus) and clustering in the genus Pipapillomavirus (Pi-PV), is only the second PV type isolated from the subfamily of hamsters. In silico analysis of three independent complete viral genomes obtained from cervical adenocarcinoma, oral squamous cell carcinoma and normal oral mucosa revealed that PsuPV1 encodes characteristic viral proteins (E1, E2, E4, E6, E7, L1 and L2) with conserved functional domains and a highly conserved non-coding region. The overall high prevalence (102/114; 89.5 %) of PsuPV1 infection in normal oral and anogenital mucosa suggests that asymptomatic infection with PsuPV1 is very frequent in healthy Siberian hamsters from an early age onward, and that the virus is often transmitted between both anatomical sites. Using type-specific real-time PCR and chromogenic in situ hybridization, the presence of PsuPV1 was additionally detected in several investigated tumours (cervical adenocarcinoma, cervical adenomyoma, vaginal carcinoma in situ, ovarian granulosa cell tumour, mammary ductal carcinoma, oral fibrosarcoma, hibernoma and squamous cell papilloma) and normal tissues of adult animals. In the tissue sample of the oral squamous cell carcinoma individual, punctuated PsuPV1-specific in situ hybridization spots were detected within the nuclei of infected animal cells, suggesting viral integration into the host genome and a potential etiological association of PsuPV1 with sporadic cases of this neoplasm.

Why Human Papillomavirus Acute Infections Matter

Most infections by human papillomaviruses (HPVs) are `acute', that is non-persistent. Yet, for HPVs, as for many other oncoviruses, there is a striking gap between our detailed understanding of chronic infections and our limited data on the early stages of infection. Here we argue that studying HPV acute infections is necessary and timely. Focusing on early interactions will help explain why certain infections are cleared while others become chronic or latent. From a molecular perspective, descriptions of immune effectors and pro-inflammatory pathways during the initial stages of infections have the potential to lead to novel treatments or to improved handling algorithms. From a dynamical perspective, adopting concepts from spatial ecology, such as meta-populations or meta-communities, can help explain why HPV acute infections sometimes last for years. Furthermore, cervical cancer screening and vaccines impose novel iatrogenic pressures on HPVs, implying that anticipating any viral evolutionary response remains essential. Finally, hints at the associations between HPV acute infections and fertility deserve further investigation given their high, worldwide prevalence. Overall, understanding asymptomatic and benign infections may be instrumental in reducing HPV virulence.

Changing Stem Cell Dynamics during Papillomavirus Infection: Potential Roles for Cellular Plasticity in the Viral Lifecycle and Disease

Stem cells and cellular plasticity are likely important components of tissue response to infection. There is emerging evidence that stem cells harbor receptors for common pathogen motifs and that they are receptive to local inflammatory signals in ways suggesting that they are critical responders that determine the balance between health and disease. In the field of papillomaviruses stem cells have been speculated to play roles during the viral life cycle, particularly during maintenance, and virus-promoted carcinogenesis but little has been conclusively determined. I summarize here evidence that gives clues to the potential role of stem cells and cellular plasticity in the lifecycle papillomavirus and linked carcinogenesis. I also discuss outstanding questions which need to be resolved.

Mechanisms and strategies of papillomavirus replication

Animal and human papillomaviruses (HPVs) replicate persistently in specific types of stratified epithelia of their host. After the initial infection, the viral genome replicates at low levels in the dividing cells of the epithelium, and these cells form a reservoir of infection that can last for decades. When the infected cells differentiate, viral genomes replicate to high levels to form progeny virus that is released from the surface of the epithelium. This complex life cycle requires several different modes of viral DNA replication, but papillomaviruses are masters at hijacking key cellular processes to facilitate their own reproduction.

[The detection of the human papilloma virus during hyperplastic processes in the nose, ears and throat]

The objective of the present work was to carry out the virological and histological studies of various neoplastic and hyperplastic processes in the nose, ears, and throat with a view to identifying the presence of human papilloma virus and Epstein-Barr virus. The brush biopsies and remote neoplasms obtained from 18 patients (including 2 children and 16 adults) presenting with various ENT diseases and tumours were available for the virological investigation with the use of the polymerase chain reaction (PCR) and a system MY09-MY11 degenerate primers . The histological study of biopsies and remote neoplasms was carried out by means of conventional light microscopy. The virological and histological studies conducted in parallel confirmed the diagnostic significance of morphological changes at the tissue and cellular levels caused by the human papilloma virus.

Reactivation of Latent HPV Infections After Renal Transplantation

Female renal transplant recipients (RTRs) have an increased risk for developing human papillomavirus (HPV)-related (pre)malignant lesions of the genital tract. This study aims to assess the genital prevalence of HPV before and after renal transplantation (RT). In female patients who were counseled for RT at the Radboud University Medical Center Nijmegen, the Netherlands, gynecological examination was performed at first visit, and 1 and 2 years later. HPV self-sampling and questionnaires on sexual behavior were performed every 3 months. In 65 patients who underwent RT, the high-risk human papillomavirus (hrHPV) prevalence as assessed with the highly sensitive SPF₁₀ -LiPA₂₅ test increased significantly from 19% before to 31% after RT (p = 0.045). Based upon the clinically validated Cobas 4800 HPV test, the hrHPV prevalence increased from 10% before to 14% after RT (p = 0.31). During follow-up, no changes in sexual behavior were reported. Thirty-three patients who did not undergo RT showed a hrHPV prevalence of 21% at study entry and of 27% after 12 months with the sensitive test, and a stable prevalence of 16% with the clinically validated test. The results of this study indicate that activation of latent HPV infections may contribute to the increased risk of HPV-related (pre)malignant lesions in female RTRs.