Treatment of genital warts: Facts and controversies

The expression and significance of PD-L1 in condyloma acuminatum

BACKGROUND

It has been reported that programmed death-ligand 1 (PD-L1) is highly expressed in cells during viral infection, which helps the virus escape host immunity. However, the relationship between human papillomavirus (HPV) and PD-L1 in condyloma acuminatum and whether they participate in immunosuppression have not been reported. In this paper, we aimed to explore the expression and significance of PD-L1 in condyloma acuminatum.

METHODS

The expression of PD-L1 in the wart of condyloma acuminatum patients and the foreskin of healthy individuals was evaluated. Lentivirus transfection was used to introduce the HPV11-E7 gene into HaCaT cells to investigate whether HPV infection could affect the expression of PD-L1. The successfully constructed HPV11-E7 HaCaT cells were cocultured with Jurkat cells, and Jurkat cell apoptosis and proliferation as well as the Jurkat cell cycle were evaluated by flow cytometry and cell counting kit-8 (CCK-8) assays.

RESULTS

PD-L1 was highly expressed in keratinocytes of genital warts. Through the construction of a cell model, we found that HPV11-E7 could upregulate the expression of PD-L1 in HaCaT cells. Furthermore, HPV11-E7 HaCaT cells can promote the apoptosis of Jurkat cells, inhibit the proliferation of Jurkat cells and mediate the cell cycle arrest of Jurkat cells through the PD-1/PD-L1 signalling pathway.

CONCLUSIONS

HPV infection may upregulate PD-L1 expression in the keratinocytes of genital warts and participate in the inhibition of local T-cell function.

Role of the Ribonuclease ONCONASE in miRNA Biogenesis and tRNA Processing: Focus on Cancer and Viral Infections

The majority of transcribed RNAs do not codify for proteins, nevertheless they display crucial regulatory functions by affecting the cellular protein expression profile. MicroRNAs (miRNAs) and transfer RNA-derived small RNAs (tsRNAs) are effectors of interfering mechanisms, so that their biogenesis is a tightly regulated process. Onconase (ONC) is an amphibian ribonuclease known for cytotoxicity against tumors and antiviral activity. Additionally, ONC administration in patients resulted in clinical effectiveness and in a well-tolerated feature, at least for lung carcinoma and malignant mesothelioma. Moreover, the ONC therapeutic effects are actually potentiated by cotreatment with many conventional antitumor drugs. This review not only aims to describe the ONC activity occurring either in different tumors or in viral infections but also to analyze the molecular mechanisms underlying ONC pleiotropic and cellular-specific effects. In cancer, data suggest that ONC affects malignant phenotypes by generating tRNA fragments and miRNAs able to downregulate oncogenes expression and upregulate tumor-suppressor proteins. In cells infected by viruses, ONC hampers viral spread by digesting the primer tRNAs necessary for viral DNA replication. In this scenario, new therapeutic tools might be developed by exploiting the action of ONC-elicited RNA derivatives.

Predictors associated with and the prevalence of condylomata acuminata infection among people in Southern Brazil

Objectives:  To estimate the prevalence of condylomata acuminata/HPV and evaluate associated predictors in infected patients. Methods: In this cross-sectional and retrospective study, medical records of patients who attended a public health referral center located in Southern Brazil, Parana, between April 2012 and March 2017 were reviewed. Epidemiological, clinical, and laboratory data were analyzed using the chi-square and odds ratio (OR) with 95% confidence interval (CI). Results: The overall prevalence of condylomata acuminata/HPV in 3,447 patients was 33.1% (n = 1,140). Coinfection of condylomata/HPV with other STI was noted in 23.7% (n = 270) of cases. The population was characterized by a high prevalence (43.8%) in patients aged < 20 years, women (37.4%), white (33.3%), educational level with more than 8 years of study (33.7%), widowed (39.2%), heterosexual (36.7%), and ages between 13 and 19 years at first sexual intercourse (41.1%). A significant association was observed between male sex and multiple partners and between male sex and irregular use of condoms (p < 0.001). The predictors associated with HPV infection were the age group of up to 29 years (OR 2.0, 95% CI 1.3–3.7, p < 0.013) and homosexual/bisexual (OR 0.2, 95% CI 0.12–0.66, p = 0.003). Conclusion: The findings showed a high prevalence of condylomata acuminata in a public health center study, with emphasis on the age range below the third decade of life and sexual behavior predictors. These predictors are important for the determination of preventive measures against the transmission of infection and the development of cancer.

HPV-11 variability, persistence and progression to genital warts in men: the HIM study

HPV-11 and HPV-6 are the etiological agents of about 90 % of genital warts (GWs). The intra-typic variability of HPV-11 and its association with infection persistence and GW development remains undetermined. Here, HPV infection in men (HIM) participants who had an HPV-11 genital swab and/or GW, preceded or not by a normal skin genital swab were analysed. Genomic variants were characterized by PCR-sequencing and classified within lineages (A, B) and sublineages (A1, A2, A3, A4). HPV-11 A2 variants were the most frequently detected in the genital swab samples from controls and in both genital swabs and GW samples from cases. The same HPV-11 variant was detected in the GW sample and its preceding genital swab. There was a lack of association between any particular HPV-11 variant and the increased risk for GW development.

HPV-6 Molecular Variants Association With the Development of Genital Warts in Men: The HIM Study

Background

Human papillomavirus type 6 (HPV-6) and HPV-11 are the etiological agents of approximately 90% of genital warts (GWs). The impact of HPV-6 genetic heterogeneity on persistence and progression to GWs remains undetermined.

Methods

HPV Infection in Men (HIM) Study participants who had HPV-6 genital swabs and/or GWs preceded by a viable normal genital swab were analyzed. Variants characterization was performed by polymerase chain reaction sequencing and samples classified within lineages (A, B) and sublineages (B1, B2, B3, B4, B5). Country- and age-specific analyses were conducted for individual variants; odds ratios and 95% confidence intervals for the risk of GWs according to HPV-6 variants were calculated.

Results

B3 variants were most prevalent. HPV-6 variants distribution differed between countries and case status. HPV-6 B1 variants prevalence was increased in GWs and genital swabs of cases compared to controls. There was difference in B1 and B3 variants detection in GW and the preceding genital swab. We observed significant association of HPV-6 B1 variants detection with GW development.

Conclusions

HPV-6 B1 variants are more prevalent in genital swabs that precede GW development, and confer an increased risk for GW. Further research is warranted to understand the possible involvement of B1 variants in the progression to clinically relevant lesions.

Ranpirnase eradicates human papillomavirus in cultured cells and heals anogenital warts in a Phase I study

BACKGROUND

Human papillomaviruses (HPV), the causative agents of anogenital warts, are the most prevalent sexually transmitted infectious agents, and wart treatment poses a persistent challenge. We assessed the safety and efficacy of treating HPV with ranpirnase, an endoribonuclease from the northern leopard frog that has been used extensively in Phase III oncology trials.

METHODS

As initial verification of ranpirnase antiviral activity, we assessed its ability to eliminate papillomaviruses in cultured cells. To further assess its feasibility for treating anogenital warts in humans, we performed a Phase I study. Forty-two male volunteers with genital/perianal warts were treated topically with three different formulations of 1 mg/ml ranpirnase. Patients were monitored for 8 weeks or until healing. Four patients with HIV were treated in accordance with the compassionate programme but were not evaluated.

RESULTS

In cultured cells, ranpirnase showed specific activity against HPV-11 with low toxicity (selectivity index >88). The broad applicability of ranpirnase for treating papillomaviruses was verified using the cottontail rabbit papillomavirus. In the clinical study, eight participants were lost-to-follow-up or discontinued due to protocol violation or non-compliance. Among 30 evaluable participants, topical ranpirnase was moderately well-tolerated, with discontinuation by 5 (16.7%) due to adverse reactions. Clinical healing was achieved by 25 participants (83.3%) and 50% improvement by the 5 discontinued participants (16.7%). The median time to clinical healing was 30 days.

CONCLUSIONS

This study provides the first in vitro and clinical evidence of the antiviral efficacy of ranpirnase against HPV and supports assessment of ranpirnase in expanded clinical studies.

The four steps in the prevention of human papillomavirus-associated neoplasia: considerations for preventive measures, screening, disease impact, and potential overtreatments in HPV-related pathology

There is no cure currently available for HPV infections, although ablative and excisional treatments of some dysplasias often result in a clinical and virological cure. Effective control measures of HPV-associated cancers rely on the prevention at four different levels. Apart from sexual abstinence, primary prevention is realized through vaccines targeting the most frequent HPV types: negative attitudes towards HPV vaccination and high costs are the main obstacles. The aim of secondary prevention is to detect precancerous changes before they develop into invasive cancer, while tertiary prevention involves actual treatment of high-grade lesions: in many countries routine screening with cytology is being challenged with HPV DNA testing. Quaternary prevention comprehends those actions adopted to mitigate or avoid unnecessary or excessive medical interventions, and may well be addressed in avoiding treatments for low-grade intraepithelial neoplasia. Though some gynecologists commonly recommend treatment for low-grade disease and women tend to prefer active management if not properly informed, harms arising from unnecessary treatments, increased costs, work overload for second-level health services, and induced psychosocial distress are causing on-going problems. Prevention efforts of genital HPV-associated cancers should concentrate in: (1) enhancing primary prevention through vaccination of all eligible subjects, (2) achieving high levels of adherence to routine screening programs, (3) treating precancerous lesions, and (4) monitoring current guidelines recommendations to avoid overtreatments. Novel research projects should be designed to study the delicate mechanisms of immune response to HPV.

Anogenital Warts in Childhood - Always a Marker for Sexual Abuse?

Human papilloma viruses (HPV) are common pathogens associated with a wide range of cutaneous and mucosal infections in childhood. Different HPV types can cause common warts and anogenital warts. Condylomata acuminata in children may be, but are not necessarily, an indicator of sexual abuse. Each individual case therefore requires careful examination, with consideration of other possible means of transmission. Diagnosis of anogenital warts is generally by means of clinical examination. Additional histological, serological or molecular genetic investigation may be indicated occasionally. The high rate of spontaneous remission and the rate of recurrence after treatment should be considered. The available topical and surgical treatment options are discussed.

[New surgical approaches for the treatment of anogenital HPV infections]

HPV infections in the anogenital region may have very heterogeneous clinical features. Most often typical papillomatous condylomata acuminata are observed that usually present no differential diagnostic difficulty. In contrast, the clinical findings of higher grade intraepithelial dysplasias with flat papules and erythematous/ eczematous lesions are often quite inconspicuous and hardly characteristic. The goal of therapy is to prevent further progression to carcinoma, removal of bothersome tumors and avoidance of complications. Surgical methods are preferentially employed for extensive lesions, unfavorable locations and higher grade dysplasia. Options include removal with scissors or scalpel, laser therapy and electrocautery. For purely intraepithelial alterations, superficial ablative techniques are usually preferable over excision. Further developments such as argon plasma coagulation reduce the risk of unwanted deep thermal destruction with the accompanying complications. The risks for the surgeon and the surgical team during treatment should also not be neglected. With consideration of all relevant aspects, the combination of different methods may reduce the risk of complications and frequency of recurrences. Due to the high recurrence rate independent of the selected therapy, consistent follow-up after primary therapy is crucial for the long-term success.