Topical treatment of CIN 2+ by cidofovir: results of a phase II, double-blind, prospective, placebo-controlled study

Topical delivery of drugs in the treatment of high-grade cervical squamous intraepithelial lesions: A meta-analysis

OBJECTIVE

The present study aims to evaluate the efficacy and effect of localized delivery of drugs in the treatment of high-grade squamous intraepithelial lesion (HSIL) based on a meta-analysis.

STUDY DESIGN

Databases including Cochrane Library, PubMed, Embase, Scopus, CNKI, and Wanfang were searched from their inception till August 2022. Randomized controlled trials (RCTs) that compared the efficacy of drugs and surgery in the treatment of HSIL were collected. A meta-analysis was performed using the software of Review Manager (version 5.4.1).

RESULTS

Eight RCTs involving 523 patients were included in the meta-analysis. For HSIL, the rate of cervical lesions histological regression was 69.85 % in the surgery group and 59.88 % in the drug group, there was no significant difference between the two groups [OR = 0.45, 95 % CI (0.07, 3.03), P = 0.41]. The histological regression rate of cervical lesions in the placebo group was 37.76 %, and the difference between the drug group and the placebo group was statistically significant [OR = 4.94, 95 % CI (2.65, 9.20), P < 0.00001].

CONCLUSION

A total of four drugs were involved in the eight RCTS included in this study, which were imiquimod, 5-fluorouracil (5-FU), cidofovir and interferon. The results showed that although drug administration was effective in the histological regression of HSIL, the efficacy was less than about 10% of surgical treatment. Considering the recurrence of the disease after surgery and the problems of abortion, premature delivery and premature rupture of membranes after cervical conization in reproductive women, drug therapy can be used as a supplement to surgery or conservative treatment to promote the histological regression of cervical lesions in patients with HSIL.

9-oxo-ODAs suppresses the proliferation of human cervical cancer cells through the inhibition of CDKs and HPV oncoproteins

Mucosal human papillomavirus (HPV) subtypes 16 and 18 are causative agents of cervical cancer, a leading cause of cancer-related deaths among women worldwide. In Japan, eggplant calyx is a folk remedy used to treat common warts. 9-oxo-(10E,12E)-octadecadienoic acid, isolated from eggplant calyx, may have antitumor effects. This study investigated the antitumor effects of 9-oxo-(10E, 12Z)-octadecadienoic acid and 9-oxo-(10E,12E)-octadecadienoic acid (9-oxo-ODAs) on human cervical cancer cells. 9-oxo-ODAs suppressed the proliferation of human cervical cancer cell lines (HeLa, and SiHa) in a concentration-dependent manner (IC50 = 25-50 µM). FCM analysis revealed that 9-oxo-ODAs induced apoptosis. Transcriptome, proteomics, and enrichment analyses revealed that treatment with 9-oxo-ODAs significantly altered the cell cycle and p53 pathways and decreased cyclin-dependent kinase 1 (CDK1) protein expression. Real-time PCR analysis demonstrated that 9-oxo-ODAs reduced CDK1 mRNA expression in a concentration-dependent manner. In vitro, 9-oxo-ODAs reduced the HPV oncoprotein expression. In ex vivo human cervical cancer tissues, 9-oxo-ODAs decreased CDK1 expression and increased cleaved caspase 3, an apoptosis marker. Further, 9-oxo-ODAs showed the potential to suppressed metastatic formation and growth of cervical cancer in vivo. These findings suggest that 9-oxo-ODAs induce cell cycle arrest and apoptosis in HPV-positive human cervical cancer cells, and this process involves CDK1. Consequently, 9-oxo-ODAs may be potential therapeutic agents for cervical cancer.

Emerging Treatment Options for Cervical Dysplasia and Early Cervical Cancer

DISCUSSION

of treatment strategies for cervical cancer precursors, review of medical therapies and emerging therapeutics for treatment of cervical cancers, and updates on new approaches to treating early-stage cervical cancers.

Effectiveness of topical cidofovir for treatment of refractory anal high-grade squamous intraepithelial lesion

OBJECTIVES

Ablative electrocautery is effective treating anal high-grade squamous intraepithelial lesions (HSILs). However, persistence or recurrence of the HSIL despite ablative sessions is not uncommon. The aim of this study is to assess the feasibility of topical cidofovir as salvage therapy for the management of refractory HSIL.

DESIGN

A prospective uncontrolled unicenter study of men and transgender people who have sex with men with HIV who had a refractory intra-anal HSIL after ablative treatments and who received topical cidofovir (ointment at 1%, auto-applicated, three times a week, a total of 8 weeks) as salvage therapy. Effectiveness was evaluated on-treatment defining response as resolution or regression to low-grade lesion of HSIL in the biopsy posttreatment. Tolerance and recurrences were recorded.

RESULTS

From 2017 to 2022, 23 patients with refractory intra-anal HSIL (78.3% persistent lesions, 39% affecting > 50% of circumference, and a median of six previous ablative sessions) were treated with topical cidofovir. A response was observed in 16 of 23 patients [69.5% (95% confidence interval (95% CI) 50.8-88.4)]. Local tolerance was reported as regular or bad in 13 patients (52.2%), requiring modification of the treatment in eight patients (three early discontinuation and five dose reduction). Non-serious side effects were reported. After a median follow-up of 30.3 months, two of the 16 patients with a response developed recurrent HSIL [recurrence rate, 25.4% at 12 months (95% CI, 0-35)].

CONCLUSION

Topical cidofovir could be a good option in the management of anal HSIL due to its good effectiveness, low recurrence rate, and acceptable tolerance even in difficult-to-treat lesions.

The Interaction of Human Papillomavirus Infection and Prostaglandin E2 Signaling in Carcinogenesis: A Focus on Cervical Cancer Therapeutics

Chronic infection by high-risk human papillomaviruses (HPV) and chronic inflammation are factors associated with the onset and progression of several neoplasias, including cervical cancer. Oncogenic proteins E5, E6, and E7 from HPV are the main drivers of cervical carcinogenesis. In the present article, we review the general mechanisms of HPV-driven cervical carcinogenesis, as well as the involvement of cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) and downstream effectors in this pathology. We also review the evidence on the crosstalk between chronic HPV infection and PGE2 signaling, leading to immune response weakening and cervical cancer development. Finally, the last section updates the current therapeutic and preventive options targeting PGE2-derived inflammation and HPV infection in cervical cancer. These treatments include nonsteroidal anti-inflammatory drugs, prophylactic and therapeutical vaccines, immunomodulators, antivirals, and nanotechnology. Inflammatory signaling pathways are closely related to the carcinogenic nature of the virus, highlighting inflammation as a co-factor for HPV-dependent carcinogenesis. Therefore, blocking inflammatory signaling pathways, modulating immune response against HPV, and targeting the virus represent excellent options for anti-tumoral therapies in cervical cancer.

Importance of the Immune Microenvironment in the Spontaneous Regression of Cervical Squamous Intraepithelial Lesions (cSIL) and Implications for Immunotherapy

Cervical high-grade squamous intraepithelial lesions (cHSILs) develop as a result of a persistent high-risk human papilloma virus (hrHPV) infection. The natural course of cHSIL is hard to predict, depending on a multitude of viral, clinical, and immunological factors. Local immunity is pivotal in the pathogenesis, spontaneous regression, and progression of cervical dysplasia; however, the underlying mechanisms are unknown. The aim of this review is to outline the changes in the immune microenvironment in spontaneous regression, persistence, and responses to (immuno)therapy. In lesion persistence and progression, the immune microenvironment of cHSIL is characterized by a lack of intraepithelial CD3+, CD4+, and CD8+ T cell infiltrates and Langerhans cells compared to the normal epithelium and by an increased number of CD25+FoxP3+ regulatory T cells (Tregs) and CD163+ M2 macrophages. Spontaneous regression is characterized by low numbers of Tregs, more intraepithelial CD8+ T cells, and a high CD4+/CD25+ T cell ratio. A ‘hot’ immune microenvironment appears to be essential for spontaneous regression of cHSIL. Moreover, immunotherapy, such as imiquimod and therapeutic HPV vaccination, may enhance a preexisting pro-inflammatory immune environment contributing to lesion regression. The preexisting immune composition may reflect the potential for lesion regression, leading to a possible immune biomarker for immunotherapy in cHSILs.

An Adsorptive and Antioxidant Vaginal Gel Clears High-Risk HPV- and p16/Ki-67-Associated Abnormal Cytological Cervical Findings: A post-hoc Subgroup Analysis of a Prospective Randomized Controlled Trial on CIN2 and p16 Positive CIN1

Objective: To analyze the course of p16/Ki-67-positive abnormal cytological cervical findings and high risk (hr)-HPV- and p16/Ki-67-clearances in women treated with a vaginal gel.

Methods: 172 women with a histological diagnosis of CIN2 or p16-positive CIN1 lesions were selected based on a positive cytological p16/Ki-67 test. For 3 months, 75 patients in the active arm (AA) daily administered 5 ml of a vaginal gel. Ninety seven patients in the control arm (CA) underwent no treatment (“watchful waiting”). Endpoints were cytological evolution, p16/Ki-67- and hr-HPV-clearances.

Results: At 3 months, cytological regression was observed in 76% (57/75) of patients in the AA compared with 25% (24/97) in the CA. Progression occurred in 5% (4/75) of the AA compared with 15% (15/97) of the CA. The p16/Ki-67 status change was statistically significantly (p < 0.001) in favor of the AA: 77% (58/75) became negative compared to 21% (20/97) in the CA. hr-HPV prevalence decreased significantly (p < 0.001) in the AA from 87 to 44%, while increasing in the CA from 78 to 84%. Cytological regression and p16/Ki-67 changes persisted in the AA at 6 months.

Conclusions: The vaginal gel significantly cleared hr-HPV and p16/Ki-67 and was associated with improved cytological findings, thereby potentially offering an effective option against oncogenic risk.

Clinical Trial Registration: Identifier: [ISRCTN11009040].

Efficacy and safety of an adsorbent and anti-oxidative vaginal gel on CIN1 and 2, on high-risk HPV, and on p16/Ki-67: a randomized controlled trial

PURPOSE

The effect of SAM vaginal gel, a medical device containing adsorptive silicon dioxide and antioxidative sodium selenite and citric acid, on histologically-proven cervical intraepithelial neoplasia type 2 (CIN2) as well as p16 positive CIN1, and on the presence of the onco-marker p16 was investigated.

METHODS

216 women aged 25-60 years were randomized to either receive an intravaginal daily dose of SAM gel for three 28-day periods, or be followed-up without intervention. The primary endpoint was efficacy, defined as a combined histological and cytological regression. At baseline and after 3 months participants had: a guided biopsy including p16 immunohistochemical (IHC) staining, only if a lesion was visible at colposcopy; a cervical smear for cytology, high-risk human papillomavirus (hr-HPV) and a p16/Ki-67 test. At 6 months a further cytology and p16/Ki-67 test was performed.

RESULTS

Regression of CIN lesions was observed in 78 out of 108 patients (72.2%) in the SAM gel arm and in 27 out of 108 patients (25.0%) in the control arm. Similarly, the change in the p16/Ki-67 cytological test status was significantly in favor of the treatment arm. The prevalence of hr-HPV decreased significantly (p < 0.001) in the treatment arm, from 87.0% to 39.8%, while it slightly increased in the control arm, from 78.7% to 83.3%. At 6 months the cytological regression in the treatment group and the highly significant effect on p16/Ki-67 was still present.

CONCLUSION

SAM vaginal gel enhances the regression of cervical lesions and clears hr-HPV and p16/Ki-67 in smears significantly, thus offering an active non-destructive management to prevent cervical cancer.

TRIAL REGISTRATION NUMBER

ISRCTN11009040, date of registration: 10/12/2019; https://doi.org/10.1186/ISRCTN11009040 ; retrospectively registered.

Topical therapies for the treatment of cervical intraepithelial neoplasia (CIN) 2-3: A narrative review

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CIN management is currently surveillance or surgical therapy. This review describes current research on medical therapies.

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Imiquimod is the most studied with evidence of safety and efficacy.

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5-Fluorouracil has also shown promise with two clinical trials showing efficacy as adjuvant and primary treatment.

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Antivirals therapies have produced mixed results with cidofovir showing the most potential.

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The data remains weak regarding hormonal, herbal and alternative therapies rending it difficult to draw conclusions.

Current management of Cervical Intraepithelial Neoplasia (CIN), caused by high-risk human papillomavirus (hr-HPV), is based on surveillance and surgical therapy. Procedures carry potential risks such as preterm birth, and access remains limited throughout the world. However, there are no medical therapies recommended to promote the clearance of hr-HPV infection or CIN. Ultimately, even if less efficacious than excision procedures, medical therapies have the potential to decrease cervical cancer by eliminating barriers to treatment, such as access to treatment, or serving as an adjunct to surgical treatment in both high- and low-resource settings.

This review describes current research on topical therapies with the potential for self-application for the treatment of HPV or CIN. Therapies included are immune-modulators, anti-proliferative medications, antivirals, hormones, and herbal/alternative therapies. Randomized trials of immune-modulating (imiquimod), anti-proliferative (5-fluorouracil), and anti-viral (cidofovir) therapies have had the most promising results. However, no option has sufficient clinical trial evidence to be recommended as treatment for CIN 2–3 and surgery remains the standard of care.

The research described in this review serves as a guide for the development of future trials in the burgeoning arena of topical therapies for CIN 2–3.

Current strategies against persistent human papillomavirus infection (Review)

Human papillomavirus (HPV) is the most common sexually transmitted infection, exhibiting a tropism for the epidermis and mucosae. The link between persistent HPV infection and malignancies involving the anogenital tract as well as the head and neck has been well‑established, and it is estimated that HPV‑related cancers involving various anatomical sites account for 4.5% of all human cancers. Current prophylactic vaccines against HPV have enabled the prevention of associated malignancies. However, the sizeable population base of current infection in whom prophylactic vaccines are not applicable, certain high‑risk HPV types not included in vaccines, and the vast susceptible population in developing countries who do not have access to the costly prophylactic vaccines, put forward an imperative need for effective therapies targeting persistent infection. In this article, the life cycle of HPV, the mechanisms facilitating HPV evasion of recognition and clearance by the host immune system, and the promising therapeutic strategies currently under investigation, particularly antiviral drugs and therapeutic vaccines, are reviewed.

Long Term Effectiveness of Photodynamic Therapy for CIN Treatment

(1) Background: Cervical cancer is the third most commonly diagnosed cancer and the fourth leading cause of cancer death in women worldwide. The highest incidence rates are in Africa, followed by South-Central Asia and South America. According to the Brazilian National Institute of Cancer (INCA), 16,370 new cases of cervical cancer were estimated for each year of the biennium of 2018-2019. About 90% of cervical cancers originate from the malignant progression of cervical intraepithelial neoplasia (CIN) which is classified based on cytohistological characteristics (low- and high-grade lesions). The present study reports the long-term effectiveness of topical photodynamic therapy (PDT) for CIN grades 1 and 2/3 with up to two years of follow up. (2) Methods: A total of 56 patients with CIN 1, ten with CIN 2, and 14 patients for the placebo group were enrolled in this study. (3) Results: 75% (n = 42) of CIN 1 patients presented a complete response to PDT and only 23.2% (n = 13) of recurrence, progression, and/or lesions remaining two years after PDT. For CIN 2/3 patients, 90% were observed to be cured after one and two years of follow up. (4) Conclusions: PDT presented best results two years after a non-invasive, fast, and low-cost procedure and in comparison with the placebo group, preventing the progression of cervical intraepithelial neoplasia and preserving the cervix.

Impact of antiviral AV2 in the topical treatment of HPV-associated lesions of the cervix: Results of a phase III randomized placebo-controlled trial

Background

Non-surgical topical therapies have been assessed in the treatment of precancerous lesions of the cervix. Their use can offer logistical and feasibility advantages in low-resource settings. Antiviral AV2^® is a mixture of natural essential oils (eugenol, carvone, nerolidol, geraniol) in olive oil, and has a broad spectrum anti-viral activity. In a phase II randomized controlled trial (RCT), AV2^® proved effective in reducing the size of cervical lesions associated with human papillomavirus (HPV). The purpose of the present study was to further evaluate the efficacy of AV2 over placebo in the topical treatment of HPV-associated cervical lesions.

Methods

Women aged 25 years and older were included in this phase 3 RCT. Cytology screening, HPV testing and visual inspection of the cervix with 5% acetic acid (VIA) were performed on all participants. VIA-positive women were randomized to one of two groups to receive treatment by either AV2® or placebo. The treatment consisted of 2 puffs of spray of the investigational drug directed to the cervix. Participants were subjected to repeat examinations two months and six months later for assessment of outcomes. The primary outcome was the change of lesions on VIA at 2 months after application of the investigational drug. Secondary outcomes were: HPV clearance and cytologic regression at 2 months and 6 months, and number of participants with AEs.

Results

A total 327 VIA positive women were randomized in two groups (168 in AV2 group and 159 in placebo group). Women in the 2 groups were similar with respect to baseline demographics and clinical characteristics. At 2 months, regression of lesions on VIA was observed in 127 (89.4%) out of 142 women in AV2 group compared to 120 (91.6%) out of 131 women in placebo group (P = 0.7). On cytology, regression of lesions occurred in 14 (56%) out of 25 women in the AV2 arm and in 13 (48.1) out of 27 women in the placebo arm (p = 0.7), and HPV clearance rates were 34.1% and 35% in AV2 group and placebo group respectively (p = 0.8). At 6 months cytologic regression was observed in 64.7% of women in AV2 group and 45.8% in placebo group (p = 0.2), while HPV clearance occurred in 11 (51.9%) out of 17 women in AV2 arm versus 11 (34.4%) in placebo arm (p = 0.3).

Some local side effects (burning, itching, irritation) were similarly noted in the 2 groups (p-values = 0.169, 0.623 and 0.172 respectively) but they were mild and transitory.

Conclusion

A topical application of AV2 onto the cervix can induce the regression of cervical precancerous lesions, but its efficacy does not significantly differ with that of placebo. The discrepancy between the expected and the recorded sample size as well as the huge number of lost to follow-up probably impeded the power of analyses, which could be one of the reasons for the lack of difference seen between AV2 and placebo. Further evaluation of the effects of AV2 with different diagnostic methods and treatment regimen and arms is warranted.

Clinical trial registration

NCT02346227 registered on November 8, 2014;

Efficacy of commercially available biological agents for the topical treatment of cervical intraepithelial neoplasia: a systematic review

BACKGROUND

Cervical cancer is a major public health issue in the world, especially in developing countries. It can be prevented through vaccination against HPV (primary prevention) and through screening and treatment of cervical intraepithelial neoplasia (CIN) (secondary prevention). Surgical methods for treatment of CIN are linked to complications such as bleeding and adverse pregnancy outcomes. Furthermore, these methods are not generally available in resource-poor settings. Therefore, topical agents for local application on the cervix have been used since decades to overpass complications and limitations of the surgical methods.

AIMS

Review of the literature on the efficacy of commercially available biological agents used for topical treatment of cervical intraepithelial neoplasia (CIN).

METHODS

A systematic search through PubMed and the Cochrane database was performed up to December 2017, using the medical subheadings (MesH) for topical agent, treatment, and cervical intraepithelial neoplasia. Appropriate inclusion/exclusion criteria have been used for the selection of eligible clinical studies. Clinical studies containing a minimum of 20 women, aged 18-50 with a diagnosis of CIN 1-3, and at least a 4 weeks follow-up after the end of the topical treatment were included.

RESULTS

The initial electronic database search resulted in a total of 849 articles. After screening titles and abstracts, 62 articles were selected as potential studies. Of these, six articles were included in the review after reading the full text: two were on 5-FluoroUracil, two on trans retinoic acid, one on Imiquimod, and one on Cidofovir. The reported regression/remission rates for CIN differed among studies. In CIN2 patients, the overall remission rate ranged between 43 and 93% for the active agents.

CONCLUSION

Among the topical agents studied, 5-FluoroUracil showed good remission rates above 80%. Varying results seen in this review is due to the differences in quality of the design between studies. Large-scale and less biaised studies are needed to elucidate the true efficacy and safety of topical agents in the treatment of CIN.

High-dose-rate brachytherapy for high-grade vaginal intraepithelial neoplasia: a dosimetric analysis

Purpose

Due to the rarity of vaginal intraepithelial neoplasia (VAIN), it is impossible to define the best treatment approach or to assess vaginal morbidity. However, brachytherapy (BT) could be a valuable choice for VAIN grade 3 (VAIN3). The aim of this paper was to report a single-institution study of the application of high-dose-rate BT and to evaluate clinical outcomes as well as to investigate the dose-effect relationship for vaginal stenosis.

Material and methods

We retrospectively collected hospital records and treatment plans of 14 consecutive women treated in our department from August 2010 to August 2016, with HDR-BT delivered using iridium-192 by a remote after-loading system. Doses in 3D-planned treatment based on computed tomography (CT) were prescribed in high-risk clinical target volume (HR-CTV) at the vaginal wall. Vaginal stenosis was defined as vaginal shortening/narrowing according to CTCAE4.1. The International Commission on Radiation Units & Measurements (ICRU) bladder and rectal points were used for dose report analysis. The posterior-inferior border of the symphysis points was used to derive reference points. The median age of the enrolled women was 60 years, and the median total radiation dose delivered was 35 Gy.

Results

During a median period of 15 days, the treatment was well tolerated, and no interruption was necessary. Acute toxicity was minimal, whereas late toxicity appeared in 4 patients as G2 and in 3 patients as G3 vaginal stenosis. Patients with stenosis G ≥ 2 received a higher median dose to the rectal point and were mainly over 60 years old.

Conclusions

Patients with VAIN3 seemed to benefit from BT. It is generally assumed that the vagina is radio-resistant, and no constraints have yet been set, but sexual dysfunction after BT is an important cause of long-term distress. Finding applicable dose limits to the vagina could improve patients’ quality of life.

Cidofovir is active against human papillomavirus positive and negative head and neck and cervical tumor cells by causing DNA damage as one of its working mechanisms

Human papillomavirus (HPV) causes cervical cancer and a large fraction of head and neck squamous cell carcinomas (HNSCC). Cidofovir (CDV) proved efficacious in the treatment of several HPV-induced benign and malignant hyper proliferations. To provide a better insight into how CDV selectively eradicates transformed cells, HPV+ and HPV- cervical carcinoma and HNSCC cell lines were compared to normal cells for antiproliferative effects, CDV metabolism, drug incorporation into cellular DNA, and DNA damage. Incorporation of CDV into cellular DNA was higher in tumor cells than in normal cells and correlated with CDV antiproliferative effects, which were independent of HPV status. Increase in phospho-ATM levels was detected following CDV exposure and higher levels of γ-H2AX (a quantitative marker of double-strand breaks) were measured in tumor cells compared to normal cells. A correlation between DNA damage and CDV incorporation into DNA was found but not between DNA damage and CDV antiproliferative effects. These data indicate that CDV antiproliferative effects result from incorporation of the drug into DNA causing DNA damage. However, the anti-tumor effects of CDV cannot be exclusively ascribed to DNA damage. Furthermore, CDV can be considered a promising broad spectrum anti-cancer agent, not restricted to HPV+ lesions.

A stratified randomized double-blind phase II trial of celecoxib for treating patients with cervical intraepithelial neoplasia: The potential predictive value of VEGF serum levels: An NRG Oncology/Gynecologic Oncology Group study

PURPOSE

To examine the effect of celecoxib on cervical intraepithelial neoplasia 3 (CIN 3). This is a NRG Oncology/Gynecologic Oncology Group study with translational biomarkers.

PATIENTS AND METHODS

Patients with CIN 3 were randomized to celecoxib 400mg once daily (67 patients) or placebo (63 patients) for 14-18weeks. The primary outcome measure was histologic regression. A test of equal probabilities of success between two therapies was conducted, using Fisher's Exact Test at alpha=10% and 90% power when the treatment arm boosted the probability of success by 30%. Translational analysis included cervical tissue HPV genotyping, COX-2 expression in biopsies, and serum celecoxib and VEGF levels.

RESULTS

In primary analysis, histologic regression was not significantly higher in the celecoxib group (40%) than in the placebo group (34.1%). However, exploratory analyses suggest patients with high serum VEGF levels exhibited greater regression in the celecoxib arm (47.3%) than in the placebo arm (14.3%). Regression rates were similar by treatment group in patients with low VEGF. VEGF levels increased over time in the placebo group, but remained the same in the treatment group. COX-2 expression in cervical biopsies declined from pre-treatment to the end of treatment with celecoxib; it did not change with placebo.

CONCLUSIONS

Celecoxib at 400mg once daily for 14-18weeks did not significantly decrease the severity of CIN 3 compared with placebo except, possibly, in subjects with high baseline VEGF. Therefore, serum VEGF levels might identify patients who may benefit from celecoxib or other therapies, personalizing future chemoprevention trials for CIN 3.

Synthesis and Antiviral Evaluation of Octadecyloxyethyl Benzyl 9-[(2-Phosphonomethoxy)ethyl]guanine (ODE-Bn-PMEG), a Potent Inhibitor of Transient HPV DNA Amplification

Human papillomavirus (HPV) high-risk genotypes such as HPV-16 and HPV-18 cause the majority of anogenital tract carcinomas, including cervical cancer, the second most common malignancy in women worldwide. Currently there are no approved antiviral agents that reduce or eliminate HPV and reverse virus-associated pathology. We synthesized and evaluated several alkoxyalkyl acyclic nucleoside phosphonate diesters and identified octadecyloxyethyl benzyl 9-[(2-phosphonomethoxy)ethyl]guanine (ODE-Bn-PMEG) as an active compound which strongly inhibited transient amplification of HPV-11, -16, and -18 origin-containing plasmid DNA in transfected cells at concentrations well below its cytotoxic concentrations. ODE-Bn-PMEG demonstrated increased uptake in human foreskin fibroblast cells and was readily converted in vitro to the active antiviral metabolite, PMEG diphosphate. The P-chiral enantiomers of ODE-Bn-PMEG were obtained and appeared to have equivalent antiviral activities against HPV. ODE-Bn-PMEG is a promising candidate for the local treatment of HPV-16 and HPV-18 and other high-risk types, an important unmet medical need.

TOPical Imiquimod treatment of high-grade Cervical intraepithelial neoplasia (TOPIC trial): study protocol for a randomized controlled trial

Background

Cervical intraepithelial neoplasia (CIN) is the premalignant condition of cervical cancer. Whereas not all high grade CIN lesions progress to cervical cancer, the natural history and risk of progression of individual lesions remain unpredictable. Therefore, high-grade CIN is currently treated by surgical excision: large loop excision of the transformation zone (LLETZ). This procedure has potential complications, such as acute haemorrhage, prolonged bleeding, infection and preterm birth in subsequent pregnancies. These complications could be prevented by development of a non-invasive treatment modality, such as topical imiquimod treatment.

The primary study objective is to investigate the efficacy of topical imiquimod 5 % cream for the treatment of high-grade CIN and to develop a biomarker profile to predict clinical response to imiquimod treatment. Secondary study objectives are to assess treatment side-effects, disease recurrence and quality of life during and after different treatment modalities.

Methods/design

The study design is a randomized controlled trial. One hundred forty women with a histological diagnosis of high-grade CIN (CIN 2–3) will be randomized into two arms: imiquimod treatment during 16 weeks (experimental arm) or immediate LLETZ (standard care arm). Treatment efficacy will be evaluated by colposcopy with diagnostic biopsies at 20 weeks for the experimental arm. Successful imiquimod treatment is defined as regression to CIN 1 or less, successful LLETZ treatment is defined as PAP 1 after 6 months. Disease recurrence will be evaluated by cytology at 6, 12 and 24 months after treatment. Side-effects will be evaluated using a standardized report form. Quality of life will be evaluated using validated questionnaires at baseline, 20 weeks and 1 year after treatment. Biomarkers, reflecting both host and viral factors in the pathophysiology of CIN, will be tested at baseline with the aim of developing a predictive biomarker profile for the clinical response to imiquimod treatment.

Discussion

Treatment of high-grade CIN lesions with imiquimod in a selected patient population may diminish complications as a result of surgical intervention. More knowledge on treatment efficacy, side effects and long-term recurrence rates after treatment is necessary.

Trial registration

EU Clinical Trials Register EU-CTR2013-001260-34. Registered 18 March 2013.

Medical Ethical Committee approval number: NL44336.068.13 (Medical Ethical Committee Maastricht University Hospital, University of Maastricht).

Affiliation: Maastricht University Hospital.

Registration number ClinicalTrials.gov: NCT02329171.

A Single-Arm, Proof-Of-Concept Trial of Lopimune (Lopinavir/Ritonavir) as a Treatment for HPV-Related Pre-Invasive Cervical Disease

BACKGROUND

Cervical cancer is the most common female malignancy in the developing nations and the third most common cancer in women globally. An effective, inexpensive and self-applied topical treatment would be an ideal solution for treatment of screen-detected, pre-invasive cervical disease in low resource settings.

METHODS

Between 01/03/2013 and 01/08/2013, women attending Kenyatta National Hospital's Family Planning and Gynaecology Outpatients clinics were tested for HIV, HPV (Cervista®) and liquid based cervical cytology (LBC-ThinPrep®). HIV negative women diagnosed as high-risk HPV positive with high grade squamous intraepithelial lesions (HSIL) were examined by colposcopy and given a 2 week course of 1 capsule of Lopimune (CIPLA) twice daily, to be self-applied as a vaginal pessary. Colposcopy, HPV testing and LBC were repeated at 4 and 12 weeks post-start of treatment with a final punch biopsy at 3 months for histology. Primary outcome measures were acceptability of treatment with efficacy as a secondary consideration.

RESULTS

A total of 23 women with HSIL were treated with Lopimune during which time no adverse reactions were reported. A maximum concentration of 10 ng/ml of lopinavir was detected in patient plasma 1 week after starting treatment. HPV was no longer detected in 12/23 (52.2%, 95%CI: 30.6-73.2%). Post-treatment cytology at 12 weeks on women with HSIL, showed 14/22 (63.6%, 95%CI: 40.6-82.8%) had no dysplasia and 4/22 (18.2%, 95%CI: 9.9-65.1%) were now low grade demonstrating a combined positive response in 81.8% of women of which 77.8% was confirmed by histology. These data are supported by colposcopic images, which show regression of cervical lesions.

CONCLUSIONS

These results demonstrate the potential of Lopimune as a self-applied therapy for HPV infection and related cervical lesions. Since there were no serious adverse events or detectable post-treatment morbidity, this study indicates that further trials are clearly justified to define optimal regimes and the overall benefit of this therapy.

TRIAL REGISTRATION

ISRCTN Registry 48776874.

The broad-spectrum anti-DNA virus agent cidofovir inhibits lung metastasis of virus-independent, FGF2-driven tumors

The FDA-approved anti-DNA virus agent cidofovir (CDV) is being evaluated in phase II/III clinical trials for the treatment of human papillomavirus (HPV)-associated tumors. However, previous observations had shown that CDV also inhibits the growth of vascular tumors induced by fibroblast growth factor-2 (FGF2)-transformed FGF2-T-MAE cells. Here, we demonstrate that CDV inhibits metastasis induced by FGF2-driven, virus-independent tumor cells. Pre-treatment of luciferase-expressing FGF2-T-MAE cells with CDV reduced single cell survival and anchorage-independent growth in vitro and lung metastasis formation upon intravenous inoculation into SCID mice. This occurred in the absence of any effect on homing of FGF2-T-MAE cells to the lungs and on the growth of subconfluent cell cultures or subcutaneous tumors in mice. Accordingly, CDV protected against lung metastasis when given systemically after tumor cell injection. Lung metastases in CDV-treated mice showed reduced Ki67 expression and increased nuclear accumulation of p53, indicating that CDV inhibits metastasis by affecting single cell survival properties. The anti-metastatic potential of CDV was confirmed on B16-F10 melanoma cells, both in zebrafish embryos and mice. These findings suggest that CDV may have therapeutic potential as an anti-metastatic agent and warrants further study to select those tumor types that are most likely to benefit from CDV therapy.

Topical cidofovir to treat high-grade anal intraepithelial neoplasia in HIV-infected patients: a pilot clinical trial

OBJECTIVE

To evaluate the efficacy of 1% topical cidofovir cream for the treatment of anal high-grade squamous intraepithelial lesions (HSILs) in HIV-infected individuals.

DESIGN

Single-arm, open-label, pilot clinical trial.

METHODS

The study medication was applied intraanally three times per week for 4 weeks. Lesions were assessed with high-resolution anoscopy and biopsy at weeks 12 and 24. The primary endpoint was complete remission (CR) at week 12, defined as clinical and histological remission. We also evaluated partial remission defined as regression to low-grade squamous intraepithelial lesion.

RESULTS

We included 17 HIV-infected patients with intraanal HSIL. Median (interquartile range) age was 36 years (28-41), median (interquartile range) CD4 cell count was 545 cells/μl (358-630), and viral load was less than 50  copies/ml in 93.7%. Two patients were lost to follow-up, one of them did not apply treatment. At 12 weeks, in the intention-to-treat population, 10 out of 16 patients [62.5%; 95% confidence interval (CI), 38.2-85.7%] had achieved CR. At 24 weeks, seven of the 10 patients (70%; 95% CI, 47-93%) remained in CR, but two out of 10 patients (20%; 95% CI, 0-40%) presented HSIL. One patient did not attend the visit at 24 weeks. Three patients with persistent HSIL at 12 weeks improved at 24 weeks (partial response in one and CR in two). The mean number of human papillomavirus genotypes decreased from 5.2 to 2.7 at 12 weeks (P = 0.002). Local adverse effects were frequent (81%), although there were no discontinuations because of adverse events.

CONCLUSION

One percent topical cidofovir could be an appropriate alternative therapy in HIV-infected patients with anal HSIL.

CLINICAL TRIAL

gov unique identifier: NCT01946009.

Antitumor action of temozolomide, ritonavir and aprepitant against human glioma cells

In the effort to find better treatments for glioblastoma we tested several currently marketed non-chemotherapy drugs for their ability to enhance the standard cytotoxic drug currently used to treat glioblastoma- temozolomide. We tested four antiviral drugs- acyclovir, cidofovir, maraviroc, ritonavir, and an anti-emetic, aprepitant. We found no cytotoxicity of cidofovir and discussed possible reasons for discrepancy from previous findings of others. We also found no cytotoxicity from acyclovir or maraviroc also in contradistinction to predictions. Cytotoxicity to glioma cell line GAMG for temozolomide alone was 14%, aprepitant alone 7%, ritonavir alone 14%, while temozolomide + aprepitant was 19%, temozolomide + ritonavir 34%, ritonavir + aprepitant 64 %, and all three, temozolomide + ritonavir + aprepitant 78%. We conclude that a remarkable synergy exists between aprepitant and ritonavir. Given the long clinical experience with these two well-tolerated drugs in treating non-cancer conditions, and the current median survival of glioblastoma of 2 years, a trial is warranted of adding these two simple drugs to current standard treatment with temozolomide.

An overview of early investigational drugs for the treatment of human papilloma virus infection and associated dysplasia

INTRODUCTION

High-risk HPV (HR-HPV) related invasive cervical cancer (ICC) causes >270,000 deaths per annum world-wide with over 85% of these occurring in low-resource countries. Ablative and excisional treatment modalities are restricted for use with high-grade pre-cancerous cervical disease with HPV infection and low-grade dysplasia mostly managed by a watch-and-wait policy.

AREAS COVERED

Various pharmacological approaches have been investigated as non-destructive alternatives for the treatment of HR-HPV infection and associated dysplasia. These are discussed dealing with efficacy, ease-of-use (physician or self-applied), systemic or locally applied, side-effects, cost and risks. The main focus is the perceived impact on current clinical practice of a self-applied, effective and safe pharmacological anti-HPV treatment.

EXPERT OPINION

Current prophylactic HPV vaccines are expensive, HPV type restricted and have little effect in already infected women. Therapeutic vaccines are under development but are also HPV type-restricted. At present, the developed nations use national cytology screening and surgical procedures to treat only women identified with HPV-related high-grade dysplastic disease. However, since HPV testing is rapidly replacing cytology as the test-of-choice, a suitable topically-applied and low-cost antiviral treatment could be an ideal solution for treatment of HPV infection per se with test-of-cure carried out by repeat HPV testing. Cytology would only then be necessary for women who remained HPV positive. Although of significant benefit in the developed countries, combining such a treatment with self-sampled HPV testing could revolutionise the management of this disease in the developing world which lack both the infrastructure and resources to establish national cytology screening programs.

Recent advances in the study of HPV-associated carcinogenesis

Human papillomaviruses (HPVs) cause virtually all cervical cancers, the second leading cause of death by cancer among women, as well as other anogenital cancers and a subset of head and neck cancers. Approximately half of women, who develop cervical cancer die from it. Despite the optimism that has accompanied the introduction of prophylactic vaccines to prevent some HPV infections, the relatively modest uptake of the vaccine, especially in the developing world, and the very high fraction of men and women who are already infected, means that HPV-associated disease will remain as a significant public health problem for decades. In this review, we summarize some recent findings on HPV-associated carcinogenesis, such as miRNAs in HPV-associated cancers, implication of stem cells in the biology and therapy of HPV-positive cancers, HPV vaccines, targeted therapy of cervical cancer, and drug treatment for HPV-induced intraepithelial neoplasias.

Emerging drugs for the treatment of cervical cancer

INTRODUCTION

Worldwide, most cervical cancer (CC) patients require the use of drug therapy either adjuvant, concurrent with radiation or palliative.

AREAS COVERED

This review briefly discusses the current achievements in treating CC with an emphasis in emerging agents.

EXPERT OPINION

Concurrent cisplatin with radiation and lately, gemcitabine-cisplatin chemoradiation has resulted in small but significant improvements in the treatment of locally advanced and high-risk early-stage patients. So far, only antiangiogenic therapy with bevacizumab added to cisplatin chemoradiation has demonstrated safety and encouraging results in a Phase II study. In advanced disease, cisplatin doublets yield median survival rates not exceeding 14 months. The first Phase III study of bevacizumab, added to standard chemotherapy cisplatin- or non-cisplatin-containing doublet, has shown significant increase in both overall survival and progression-free survival. Further studies are needed before bevacizumab plus chemotherapy can be considered the standard of care for advanced disease. The characterization of the mutational landscape of CC and developments of novel targeted therapies may result in more effective and individualized treatments for CC. The potential efficacy of knocking down the key alterations in CC, E6 and E7 human papilloma virus oncoproteins must not be overlooked.

Topical hexaminolevulinate photodynamic therapy for the treatment of persistent human papilloma virus infections and cervical intraepithelial neoplasia

INTRODUCTION

Current treatments for high-grade cervical intraepithelial neoplasia (CIN2/3) are mainly excisional procedures, which are associated with significant side effects and pose risks for future pregnancies. An effective and safe therapy is needed to reduce the requirement for surgical interventions in women of reproductive age.

AREAS COVERED

This review looks at the pharmacokinetic and clinical data for topical hexaminolevulinate (HAL) photodynamic therapy (PDT), which is currently entering late phase clinical trials for high-grade CIN. The authors include published studies in patients and volunteers but laboratory and animal studies have been excluded as have studies on other porphyrins such as Photofrin, 5-aminolevulinic acid, methyl aminolevulinate and studies reporting other clinical applications for HAL.

EXPERT OPINION

Topical HAL PDT has potential as a non-surgical tissue-preserving treatment for CIN and persistent oncogenic human papilloma virus infections. HAL PDT selectively treats the entire epithelial sheet, without the tissue destruction seen in excisional procedures. The authors believe that this treatment could replace surgery in a large proportion of patients. It would be of particular value to the high percentage of women who are interested in future child-bearing. If the treatment is approved, it is very likely that physicians will want to use this treatment, as many patients will be keen to consider a non-surgical option.

Immune therapy for human papillomaviruses-related cancers

Human papillomaviruses (HPVs) are a large family of double strand DNA viruses comprising more than 180 types. Infection with HPV is very common and it is associated with benign and malignant proliferation of skin and squamous mucosae. Many HPVs, considered low-risk such as HPV 6 and 11, produce warts; while high-risk viruses, such as HPVs 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, and 58, induce tumors. About 5% of all cancers in men and women are associated with HPV infection. Because there are not antiviral drugs for HPV infection, current therapies for low-risk HPV infections involve physical removal of the lesion by cryotherapy, trichloracetic acid, laser, or surgical removal. Surgical procedures are effective in the treatment of pre-cancerous lesions, however after these procedures, many recurrences appear due to new re-infections, or to failure of the procedure to eliminate the HPV. In addition, HPV can inhibit recognition of malignant cells by the immune system, leading to the development of cancer lesions. When this occurs, radiotherapy and chemotherapy are then used. Unfortunately, about 50% of the HPV-cancer patients still die. In the past decade, a better knowledge of the natural history of the virus-host interaction and of the immune response against this viral infection has brought new therapeutic strategies geared to modulate the immune system to generate an efficient virus-specific cytotoxic response. Novel HPV protein-expressing vaccines have shown some significant clinical efficacy and systemic HPV-specific cytotoxic T cell responses. This review will describe the current status of the several therapeutic strategies used to treat HPV-induced lesions, and discuss the various new therapies now being tested.

New molecular targets against cervical cancer

Cervical cancer is the third most commonly diagnosed cancer worldwide and the fourth leading cause of cancer death in women. Major advances but still insufficient achievements in the treatment of locally advanced and high-risk early stage patients have occurred in the last decade with the incorporation of concurrent cisplatin with radiation and, lately, gemcitabine added to cisplatin chemoradiation. Despite a number of clinical studies incorporating molecular-targeted therapy as radiosensitizers being in progress, so far, only antiangiogenic therapy with bevacizumab added to cisplatin chemoradiation has demonstrated safety and shown encouraging results in a Phase II study. In advanced disease, cisplatin doublets do not have a great impact on the natural history of the disease with median survival rates not exceeding 13 months. The first Phase III study of bevacizumab, added to cisplatin or a non-cisplatin-containing doublet, showed significant increase in both overall survival and progression-free survival. Further studies are needed before bevacizumab plus chemotherapy can be considered the standard of care for advanced disease. Characterization of the mutational landscape of cervical cancer has already been initiated, indicating that, for now, few of these targetable alterations match with available agents. Progress in both the mutational landscape knowledge and developments of novel targeted therapies may result in more effective and individualized treatments for cervical cancer. The potential efficacy of knocking down the key alterations in cervical cancer – E6 and E7 human papillomavirus oncoproteins – must not be overlooked.

Insights into the mechanism of action of cidofovir and other acyclic nucleoside phosphonates against polyoma- and papillomaviruses and non-viral induced neoplasia

Acyclic nucleoside phosphonates (ANPs) are well-known for their antiviral properties, three of them being approved for the treatment of human immunodeficiency virus infection (tenofovir), chronic hepatitis B (tenofovir and adefovir) or human cytomegalovirus retinitis (cidofovir). In addition, cidofovir is mostly used off-label for the treatment of infections caused by several DNA viruses other than cytomegalovirus, including papilloma- and polyomaviruses, which do not encode their own DNA polymerases. There is considerable interest in understanding why cidofovir is effective against these small DNA tumor viruses. Considering that papilloma- and polyomaviruses cause diseases associated either with productive infection (characterized by high production of infectious virus) or transformation (where only a limited number of viral proteins are expressed without synthesis of viral particles), it can be envisaged that cidofovir may act as antiviral and/or antiproliferative agent. The aim of this review is to discuss the advances in recent years in understanding the mode of action of ANPs as antiproliferative agents, given the fact that current data suggest that their use can be extended to the treatment of non-viral related malignancies.

Topical 5-fluorouracil for treatment of cervical intraepithelial neoplasia 2: a randomized controlled trial

OBJECTIVE

The objective of the study was to evaluate the efficacy of intravaginal application of 5% 5-fluorouracil (5-FU) for the treatment of cervical intraepithelial neoplasia (CIN) 2 in women.

STUDY DESIGN

Women aged 18-29 years with CIN 2 were recruited for this randomized controlled trial of observation vs treatment with intravaginal 5-FU. Women in the observation group returned in 6 months for a Papanicolaou smear, colposcopy, and a human papillomavirus (HPV) deoxyribonucleic acid test. Women in the 5-FU group were treated with intravaginal 5-FU once every 2 weeks for a total of 16 weeks and were similarly evaluated at 6 months. All women who had a baseline visit were included in the intention-to-treat analysis. Values of P < .05 were considered statistically significant.

RESULTS

Between August 2010 and June 2013, 60 women were randomized and had a baseline visit for intervention (n = 31) vs observation (n = 29). Of women who had cervical biopsy results at 6 months, regression of disease was demonstrated in 93% of women in the 5-FU group (26 of 28) and 56% of women in the observation group (15 of 27). Under the intention-to-treat analysis, a relative risk for cervical disease regression of 1.62 (95% confidence interval [CI], 1.10-2.56) was found between the 5-FU and observation arms (P = .01). When the cervical biopsy, Papanicolaou smear, and HPV results were combined for the 6 month follow-up visit, 50% of the 5-FU group (14 of 28) had a documented normal biopsy, normal Papanicolaou smear, and negative HPV test compared with 22% in the observation group (6 of 27) (relative risk, 2.25; 95% confidence interval, 1.05-5.09; P < .05). There were no moderate or severe side effects in the intervention group.

CONCLUSION

Topical 5-FU appears to be an effective medical therapy for CIN 2 in young women. 5-FU is readily available and may be considered as an off-label treatment option for young women with CIN 2 who are interested in the treatment of disease but want to avoid excisional procedures.

Emerging biological treatments for uterine cervical carcinoma

Cervical cancer is the third most common cancer worldwide, and the development of new diagnosis, prognostic, and treatment strategies is a major interest for public health. Cisplatin, in combination with external beam irradiation for locally advanced disease, or as monotherapy for recurrent/metastatic disease, has been the cornerstone of treatment for more than two decades. Other investigated cytotoxic therapies include paclitaxel, ifosfamide and topotecan, as single agents or in combination, revealing unsatisfactory results. In recent years, much effort has been made towards evaluating new drugs and developing innovative therapies to treat cervical cancer. Among the most investigated molecular targets are epidermal growth factor receptor and vascular endothelial growth factor (VEGF) signaling pathways, both playing a critical role in cervical cancer development. Studies with bevacizumab or VEGF receptor tyrosine kinase have given encouraging results in terms of clinical efficacy, without adding significant toxicity. A great number of other molecular agents targeting critical pathways in cervical malignant transformation are being evaluated in preclinical and clinical trials, reporting preliminary promising data.

In the current review, we discuss novel therapeutic strategies which are being investigated for the treatment of advanced cervical cancer.

Cidofovir selectivity is based on the different response of normal and cancer cells to DNA damage

Background

Cidofovir (CDV) proved efficacious in treatment of human papillomaviruses (HPVs) hyperplasias. Antiproliferative effects of CDV have been associated with apoptosis induction, S-phase accumulation, and increased levels of tumor suppressor proteins. However, the molecular mechanisms for the selectivity and antitumor activity of CDV against HPV-transformed cells remain unexplained.

Methods

We evaluated CDV drug metabolism and incorporation into cellular DNA, in addition to whole genome gene expression profiling by means of microarrays in two HPV⁺ cervical carcinoma cells, HPV^- immortalized keratinocytes, and normal keratinocytes.

Results

Determination of the metabolism and drug incorporation of CDV into genomic DNA demonstrated a higher rate of drug incorporation in HPV⁺ tumor cells and immortalized keratinocytes compared to normal keratinocytes. Gene expression profiling clearly showed distinct and specific drug effects in the cell types investigated. Although an effect on inflammatory response was seen in all cell types, different pathways were identified in normal keratinocytes compared to immortalized keratinocytes and HPV⁺ tumor cells. Notably, Rho GTPase pathways, LXR/RXR pathways, and acute phase response signaling were exclusively activated in immortalized cells. CDV exposed normal keratinocytes displayed activated cell cycle regulation upon DNA damage signaling to allow DNA repair via homologous recombination, resulting in genomic stability and survival. Although CDV induced cell cycle arrest in HPV^- immortalized cells, DNA repair was not activated in these cells. In contrast, HPV⁺ cells lacked cell cycle regulation, leading to genomic instability and eventually apoptosis.

Conclusions

Taken together, our data provide novel insights into the mechanism of action of CDV and its selectivity for HPV-transformed cells. The proposed mechanism suggests that this selectivity is based on the inability of HPV⁺ cells to respond to DNA damage, rather than on a direct anti-HPV effect. Since cell cycle control is deregulated by the viral oncoproteins E6 and E7 in HPV⁺ cells, these cells are more susceptible to DNA damage than normal keratinocytes. Our findings underline the therapeutic potential of CDV for HPV-associated malignancies as well as other neoplasias.

Genital human papillomavirus infections: current and prospective therapies

Infection with human papillomaviruses (HPVs) is very common and associated with benign and malignant epithelial proliferations of skin and internal squamous mucosae. A subset of the mucosal HPVs are oncogenic and associated with 5 % of all cancers in men and women. There are two licensed prophylactic vaccines, both target HPV 16 and 18, the two most pathogenic, oncogenic types and one, additionally, targets HPV 6 and 11 the cause of genital warts. The approach of deliberate immunization with oncogenic HPV E6 and/or E7 proteins and the generation of antigen-specific cytotoxic T-cells as an immunotherapy for HPV-associated cancer and their high-grade pre-cancers has been tested with a wide array of potential vaccine delivery systems in Phase I/II trials with varying success. Understanding local viral and tumour immune evasion strategies is a prerequisite for the rational design of therapeutic vaccines for HPV-associated infection and disease, progress in this is discussed. There are no antiviral drugs for the treatment of HPV infection and disease. Current therapies are not targeted antiviral therapies, but either attempt physical removal of the lesion or induce inflammation and a bystander immune response. There has been recent progress in the identification and characterization of molecular targets for small molecule antagonists of the HPV proteins E1, E2 and E6 or their interactions with their cellular targets. Lead compounds that could disrupt E1-E2 protein-protein interactions have been discovered as have inhibitors of E6-E6-AP-binding interactions. Some of these compounds showed nanomolar affinities and high specificities and demonstrate the feasibility of this approach for HPV infections. These studies are, however, at an early phase and it is unlikely that any specific anti-HPV chemotherapeutic will be in the clinic within the next 10-20 years.

Treatment options for anal intraepithelial neoplasia and evidence for their effectiveness

There is a growing range of treatment options for anal intraepithelial neoplasia (AIN). In HIV-positive patients, sustained treatment is often required to achieve clearance. The treatments considered are topically applied fluorouracil, imiquimod, cidofovir and trichloroacetic acid, the potential treatments of topical lopinavir and photodynamic therapy with aminolevulenic acid, and the surgical methods of electrosurgery, infrared coagulation and laser. Destructive treatment methods, possibly including TCA, are more effective than self applied topical treatments. Combining or alternating different treatments should be considered.

Cervical cancer prevention in low- and middle-income countries: feasible, affordable, essential

The annual worldwide burden of the preventable disease cervical cancer is more than 530,000 new cases and 275,000 deaths, with the majority occurring in low- and middle-income countries (LMIC), where cervical cancer screening and early treatment are uncommon. Widely used in high-income countries, Pap smear (cytology based) screening is expensive and challenging for implementation in LMICs, where lower-cost, effective alternatives such as visual inspection with acetic acid (VIA) and rapid human papillomavirus (HPV)-based screening tests offer promise for scaling up prevention services. Integrating HPV screening with VIA in "screen-and-treat-or-refer" programs offers the dual benefits of HPV screening to maximize detection and using VIA to triage for advanced lesions/cancer, as well as a pelvic exam to address other gynecologic issues. A major issue in LMICs is coinfection with human immunodeficiency virus (HIV) and HPV, which further increases the risk for cervical cancer and marks a population with perhaps the greatest need of cervical cancer prevention. Public-private partnerships to enhance the availability of cervical cancer prevention services within HIV/AIDS care delivery platforms through initiatives such as Pink Ribbon Red Ribbon present an historic opportunity to expand cervical cancer screening in LMICs.

Cervical cancer prevention in low- and middle-income countries: feasible, affordable, essential

The annual worldwide burden of the preventable disease cervical cancer is more than 530,000 new cases and 275,000 deaths, with the majority occurring in low- and middle-income countries (LMIC), where cervical cancer screening and early treatment are uncommon. Widely used in high-income countries, Pap smear (cytology based) screening is expensive and challenging for implementation in LMICs, where lower-cost, effective alternatives such as visual inspection with acetic acid (VIA) and rapid human papillomavirus (HPV)-based screening tests offer promise for scaling up prevention services. Integrating HPV screening with VIA in "screen-and-treat-or-refer" programs offers the dual benefits of HPV screening to maximize detection and using VIA to triage for advanced lesions/cancer, as well as a pelvic exam to address other gynecologic issues. A major issue in LMICs is coinfection with human immunodeficiency virus (HIV) and HPV, which further increases the risk for cervical cancer and marks a population with perhaps the greatest need of cervical cancer prevention. Public-private partnerships to enhance the availability of cervical cancer prevention services within HIV/AIDS care delivery platforms through initiatives such as Pink Ribbon Red Ribbon present an historic opportunity to expand cervical cancer screening in LMICs.

Next-generation treatment strategies for human papillomavirus-related head and neck squamous cell carcinoma: where do we go?

Oncogenic human papillomavirus (HPV) is currently recognised as a major risk factor for the development of head and neck squamous cell carcinomas (HNSCC). HPV is mostly detected in tumours arising from the oropharynx and more specifically from the tonsil. HPV-related tumours display clinical and molecular characteristics that are distinct from HPV-unrelated tumours, which are generally induced by alcohol and tobacco abuse. Detection of biologically active HPV in HNSCC has prognostic relevance, which warrants the separate classification of HPV-induced tumours and is a prerequisite for further optimisation of treatment protocols for this distinct group. Current guidelines for the treatment of oropharyngeal squamous cell carcinoma (OPSCC) have not incorporated specific treatment modalities for HPV-related tumours. The development of such treatment options is still in a preclinical phase or in early clinical trials. Recent data on treatment response of OPSCC have been obtained by retrospectively analysing HPV-status and indicate that patients with HPV-related tumours show a favourable prognosis, independent of the type of treatment. These patients may benefit from de-intensified treatment, which should be assessed in prospective clinical trials. The development and future use of new antiviral and immunomodulatory therapeutics may be instrumental in this approach to improve survival rates and decrease disease-and-treatment-related morbidity. In this review we will focus on present therapeutic HPV-targeting strategies and discuss future directions for de-intensified treatment of HPV-positive HNSCC.

Human papillomavirus: gene expression, regulation and prospects for novel diagnostic methods and antiviral therapies

Human papillomaviruses (HPVs) cause diseases ranging from benign warts to invasive tumors. A subset of these viruses termed 'high risk' infect the cervix where persistent infection can lead to cervical cancer. Although many HPV genomes have been sequenced, knowledge of virus gene expression and its regulation is still incomplete. This is due in part to the lack, until recently, of suitable systems for virus propagation in the laboratory. HPV gene expression is polycistronic initiating from multiple promoters. Gene regulation occurs at transcriptional, but particularly post-transcriptional levels, including RNA processing, nuclear export, mRNA stability and translation. A close association between the virus replication cycle and epithelial differentiation adds a further layer of complexity. Understanding HPV mRNA expression and its regulation in the different diseases associated with infection may lead to development of novel diagnostic approaches and will reveal key viral and cellular targets for development of novel antiviral therapies.

Stability of 0.5% cidofovir stored under various conditions for up to 6 months

OBJECTIVE

To evaluate the effect of time, temperature and storage vial material on the antiviral activity of 0.5% cidofovir solution.

PROCEDURES

Commercial 7.5% cidofovir solution for injection was diluted with normal saline to a 0.5% concentration. Aliquots were stored in plastic and glass vials at 4, -20, and -80 degrees C for 30, 60, 120, and 180 days. Antiviral activity against feline herpesvirus was evaluated in a virus titration assay at time zero (baseline) and at each subsequent time point.

RESULTS

Cidofovir caused a fourfold log reduction in virus titer at baseline and at each time point and for each storage condition (P < 0.001).

CONCLUSION

0.5% cidofovir demonstrated stable antiviral activity when stored for up to 6 months in glass or plastic, at 4, -20, and -80 degrees C.