A pilot study of pNGVL4a-CRT/E7(detox) for the treatment of patients with HPV16+ cervical intraepithelial neoplasia 2/3 (CIN2/3)

Type II interferons activate MHC-I pathway to enhance antigen presentation of grass carp reovirus VP35 DNA vaccine

Hemorrhagic disease caused by grass carp reovirus (GCRV) poses a significant threat to the health and sustainability of grass carp (Ctenopharyngodon idella) farming. There are no effective measures to control the outbreaks of the disease. While DNA vaccines have proved to be promising to enhance the survival of vaccinated fish to GCRV infection, the protective efficacy is not maximized, and necessitates further improvement. This study explores the immunomodulatory potential of type II interferons (IFNs), including IFN-γ and IFN-γ related molecule (IFN-γrel), as adjuvants for GCRV-VP35 DNA vaccine. Expression plasmids, including pcDNA3.1-VP35, pcDNA3.1-IFN-γ, and/or pcDNA3.1-IFN-γrel, were intramuscularly administered in grass carp, and their effects on the expression of immune genes evaluated. Immunofluorescence microscopy confirmed the localized expression of GCRV-VP35, IFN-γ and IFN-γrel at the injection site, with the persistent expression detected for at least five weeks. Moreover, co-administration of IFN-γ and IFN-γrel plasmids synergistically enhanced the expression of Mx1, Isg15 and Viperin to a greater extent than either plasmid alone. The Igm and Cd8 genes were also upregulated in the spleen and muscle of fish injected with the IFN-γ/IFN-γrel plasmids. Furthermore, our findings reveal that IFN-γ and IFN-γrel robustly upregulated the expression of Mhc I but not Mhc II to promote antigen presentation of VP35 vaccine. The results indicate that type II IFNs have potential as adjuvants to enhance the immunogenicity and efficacy of DNA vaccines in protecting fish against viral infection.

Structural engineering of stabilized, expanded epitope nanoparticle vaccines for HPV

Oncogenic forms of HPV account for 4.5% of the global cancer burden worldwide. This includes cervical, vaginal, vulvar, penile, and anal cancers, as well as head and neck cancers. As such, there is an urgent need to develop effective therapeutic vaccines to drive the immune system's cellular response against cancer cells. One of the primary goals of cancer vaccination is to increase the potency and diversity of anti-tumor T-cell responses; one strategy to do so involves the delivery of full-length cancer antigens scaffolded onto DNA-launched nanoparticles to improve T-cell priming. We developed a platform, making use of structural prediction algorithms such as AlphaFold2, to design stabilized, more full-length antigens of relevant HPV proteins and then display them on nanoparticles. We demonstrated that many such designs for both the HPV16 E6 and E7 antigens assembled and drove strong CD8+ T-cell responses in mice. We further tested nanoparticles in a genetically diverse, more translationally relevant CD-1 mouse model and demonstrated that both E6 and E7 nanoparticle designs drove a CD8+ biased T-cell response. These findings serve as a proof-of-concept study for nanoparticle antigen design as well as identify new vaccine candidates for HPV-associated cancers.

Roles of human papillomavirus in cancers: oncogenic mechanisms and clinical use

Human papillomaviruses, particularly high-risk human papillomaviruses, have been universally considered to be associated with the oncogenesis and progression of various cancers. The genome of human papillomaviruses is circular, double-stranded DNA that encodes early and late proteins. Each of the proteins is of crucial significance in infecting the epithelium of host cells persistently and supporting viral genome integrating into host cells. Notably, E6 and E7 proteins, classified as oncoproteins, trigger the incidence of cancers by fostering cell proliferation, hindering apoptosis, evading immune surveillance, promoting cell invasion, and disrupting the balance of cellular metabolism. Therefore, targeting human papillomaviruses and decoding molecular mechanisms by which human papillomaviruses drive carcinogenesis are of great necessity to better treat human papillomaviruses-related cancers. Human papillomaviruses have been applied clinically to different facets of human papillomavirus-related cancers, including prevention, screening, diagnosis, treatment, and prognosis. Several types of prophylactic vaccines have been publicly utilized worldwide and have greatly decreased the occurrence of human papillomavirus-related cancers, which have benefited numerous people. Although various therapeutic vaccines have been developed and tested clinically, none of them have been officially approved to date. Enhancing the efficacy of vaccines and searching for innovative technologies targeting human papillomaviruses remain critical challenges that warrant continuous research and attention in the future.

Design and evaluation of a multi-epitope DNA vaccine against HPV16

Cervical cancer, among the deadliest cancers affecting women globally, primarily arises from persistent infection with high-risk human papillomavirus (HPV). To effectively combat persistent infection and prevent the progression of precancerous lesions into malignancy, a therapeutic HPV vaccine is under development. This study utilized an immunoinformatics approach to predict epitopes of cytotoxic T lymphocytes (CTLs) and helper T lymphocytes (HTLs) using the E6 and E7 oncoproteins of the HPV16 strain as target antigens. Subsequently, through meticulous selection of T-cell epitopes and other necessary elements, a multi-epitope vaccine was constructed, exhibiting good immunogenic, physicochemical, and structural characteristics. Furthermore, in silico simulations showed that the vaccine not only interacted well with toll-like receptors (TLR2/TLR3/TLR4), but also induced a strong innate and adaptive immune response characterized by elevated Th1-type cytokines, such as interferon-gamma (IFN-γ) and interleukin-2 (IL2). Additionally, our study investigated the effects of different immunization intervals on immune responses, aiming to optimize a time-efficient immunization program. In animal model experiments, the vaccine exhibited robust immunogenic, therapeutic, and prophylactic effects. Administered thrice, it consistently induced the expansion of specific CD4 and CD8 T cells, resulting in substantial cytokines release and increased proliferation of memory T cell subsets in splenic cells. Overall, our findings support the potential of this multi-epitope vaccine in combating HPV16 infection and signify its candidacy for future HPV vaccine development.

Recent advances in HPV biotechnology: understanding host-virus interactions and cancer progression - a review

Cervical cancer ranks as the fourth most common cancer among women globally, posing a significant mortality risk. Persistent infection with high-risk human papillomavirus (HPV) is the primary instigator of cervical cancer development, often alongside coinfection with other viruses, precipitating various malignancies. This study aimed to explore recent biotechnological advances in understanding HPV infection dynamics, host interactions, and its role in oncogenesis. The gathered data shed light on HPV biology, host-virus interplay, viral coinfections, and cellular transformations leading to HPV-associated cancers. Recent years have seen the introduction of diverse vaccination strategies, including live attenuated, subunit, and DNA-based vaccines, complemented by innovative nanotechnology and plant-based products. Despite rich data addressing research inquiries, urgent calls echo for the implementation of contemporary screening and therapeutic modalities at clinical levels. Moreover, extensive public awareness campaigns are imperative to alleviate the burden of HPV-related diseases, emphasizing the necessity for proactive intervention strategies in combating this global health challenge.

Prophylactic and therapeutic vaccine development: advancements and challenges

Biomedical research is fundamental in developing preventive and therapeutic vaccines, serving as a cornerstone of global public health. This review explores the key concepts, methodologies, tools, and challenges in the vaccine development landscape, focusing on transitioning from basic biomedical sciences to clinical applications. Foundational disciplines such as virology, immunology, and molecular biology lay the groundwork for vaccine creation, while recent innovations like messenger RNA (mRNA) technology and reverse vaccinology have transformed the field. Additionally, it highlights the role of pharmaceutical advancements in translating lab discoveries into clinical solutions. Techniques like CRISPR-Cas9, genome sequencing, monoclonal antibodies, and computational modeling have significantly enhanced vaccine precision and efficacy, expediting the development of vaccines against infectious diseases. The review also discusses challenges that continue to hinder progress, including stringent regulatory pathways, vaccine hesitancy, and the rapid emergence of new pathogens. These obstacles underscore the need for interdisciplinary collaboration and the adoption of innovative strategies. Integrating personalized medicine, nanotechnology, and artificial intelligence is expected to revolutionize vaccine science further. By embracing these advancements, biomedical research has the potential to overcome existing challenges and usher in a new era of therapeutic and prophylactic vaccines, ultimately improving global health outcomes. This review emphasizes the critical role of vaccines in combating current and future health threats, advocating for continued investment in biomedical science and technology.

New insights for the development of efficient DNA vaccines

Despite the great potential of DNA vaccines for a broad range of applications, ranging from prevention of infections, over treatment of autoimmune and allergic diseases to cancer immunotherapies, the implementation of such therapies for clinical treatment is far behind the expectations up to now. The main reason is the poor immunogenicity of DNA vaccines in humans. Consequently, the improvement of the performance of DNA vaccines in vivo is required. This mini-review provides an overview of the current state of DNA vaccines and the various strategies to enhance the immunogenic potential of DNA vaccines, including (i) the optimization of the DNA construct itself regarding size, nuclear transfer and transcriptional regulation; (ii) the use of appropriate adjuvants; and (iii) improved delivery, for example, by careful choice of the administration route, physical methods such as electroporation and nanomaterials that may allow cell type-specific targeting. Moreover, combining nanoformulated DNA vaccines with other immunotherapies and prime-boost strategies may help to enhance success of treatment.

Metal-based approaches to fight cervical cancer

Cervical cancer (CC) is one of the leading causes of death among women worldwide. The current treatments for this cancer consist of invasive methods such as chemotherapeutic drugs, radiation, immunotherapy and surgery, which could lead to severe side effects and hinder the patient's life quality. Although metal-based therapies, including cisplatin and ruthenium-based compounds, offer promising alternatives, they lack specificity and harm healthy cells. Combining metal nanoparticles with standard approaches has demonstrated remarkable efficacy and safety in the fight against CC. Overall, this review is intended to show the latest advancements and insights into metal-based strategies, creating a promising path for more effective and safer treatments in the battle against CC.

Current status and future directions for the development of human papillomavirus vaccines

The development of human papillomavirus (HPV) vaccines has made substantive progress, as represented by the approval of five prophylactic vaccines since 2006. Generally, the deployment of prophylactic HPV vaccines is effective in preventing newly acquired infections and incidences of HPV-related malignancies. However, there is still a long way to go regarding the prevention of all HPV infections and the eradication of established HPV infections, as well as the subsequent progression to cancer. Optimizing prophylactic HPV vaccines by incorporating L1 proteins from more HPV subtypes, exploring adjuvants that reinforce cellular immune responses to eradicate HPV-infected cells, and developing therapeutic HPV vaccines used either alone or in combination with other cancer therapeutic modalities might bring about a new era getting closer to the vision to get rid of HPV infection and related diseases. Herein, we summarize strategies for the development of HPV vaccines, both prophylactic and therapeutic, with an emphasis on the selection of antigens and adjuvants, as well as implications for vaccine efficacy based on preclinical studies and clinical trials. Additionally, we outline current cutting-edge insights on formulation strategies, dosing schedules, and age expansion among HPV vaccine recipients, which might play important roles in addressing barriers to vaccine uptake, such as vaccine hesitancy and vaccine availability.

HPV and Cervical Cancer: Molecular and Immunological Aspects, Epidemiology and Effect of Vaccination in Latin American Women

Cervical cancer is primarily caused by Human Papillomavirus (HPV) infection and remains a significant public health concern, particularly in Latin American regions. This comprehensive narrative review addresses the relationship between Human Papillomavirus (HPV) and cervical cancer, focusing on Latin American women. It explores molecular and immunological aspects of HPV infection, its role in cervical cancer development, and the epidemiology in this region, highlighting the prevalence and diversity of HPV genotypes. The impact of vaccination initiatives on cervical cancer rates in Latin America is critically evaluated. The advent of HPV vaccines has presented a significant tool in combating the burden of this malignancy, with notable successes observed in various countries, the latter due to their impact on immune responses. The review synthesizes current knowledge, emphasizes the importance of continued research and strategies for cervical cancer prevention, and underscores the need for ongoing efforts in this field.

Safety, Efficacy, and Immunogenicity of Therapeutic Vaccines for Patients with High-Grade Cervical Intraepithelial Neoplasia (CIN 2/3) Associated with Human Papillomavirus: A Systematic Review

Despite the knowledge that HPV is responsible for high-grade CIN and cervical cancer, little is known about the use of therapeutic vaccines as a treatment. We aimed to synthesize and critically evaluate the evidence from clinical trials on the safety, efficacy, and immunogenicity of therapeutic vaccines in the treatment of patients with high-grade CIN associated with HPV. A systematic review of clinical trials adhering to the PRISMA 2020 statement in MEDLINE/PubMed, Embase, CENTRAL Cochrane, Web of Science, Scopus, and LILACS was undertaken, with no data or language restrictions. Primary endpoints related to the safety, efficacy, and immunogenicity of these vaccines were assessed by reviewing the adverse/toxic effects associated with the therapeutic vaccine administration via histopathological regression of the lesion and/or regression of the lesion size and via viral clearance and through the immunological response of individuals who received treatment compared to those who did not or before and after receiving the vaccine, respectively. A total of 1184 studies were identified, and 16 met all the criteria. Overall, the therapeutic vaccines were heterogeneous regarding their formulation, dose, intervention protocol, and routes of administration, making a meta-analysis unfeasible. In most studies (n = 15), the vaccines were safe and well tolerated, with clinical efficacy regarding the lesions and histopathological regression or viral clearance. In addition, eleven studies showed favorable immunological responses against HPV, and seven studies showed a positive correlation between immunogenicity and the clinical response, indicating promising results that should be further investigated. In summary, therapeutic vaccines, although urgently needed to avoid progression of CIN 2/3 patients, still present sparse data, requiring greater investments in a well-designed phase III RCT.

Immunotherapy that leverages HPV-specific immune responses for precancer lesions of cervical cancer

Cervical cancer and its precursor lesion, cervical intraepithelial neoplasia (CIN), are caused by high-risk human papillomavirus (HPV) viral infection and are highly susceptible to host immunity targeting of HPV viral proteins, which include both foreign antigens and cancer antigens expressed by tumors. Immunotherapy that induces Th1 immunoreactivity against viral proteins is expected to take advantage of this immunological regression mechanism. However, although cancer immunotherapies for cervical cancer and CIN have been developed over the past several decades, none have been commercialized. Most of these immunotherapies target the viral cancer proteins E6 and E7, which are generally the same. The reasons for the underdevelopment of HPV-targeted immunotherapy differ depending on whether the target is invasive cancer or CIN. We here summarize the developmental history of cancer immunotherapy for CIN and discuss strategies for solving the problems that led to this underdevelopment. We note that CIN is a mucosal lesion and propose that inducing mucosal immunity may be the key.

Human Papillomavirus Vaccines

Human papillomavirus (HPV) vaccines are highly effective in preventing the transmission of HPV and thus downstream HPV-related lower genital tract neoplasias. First introduced in 2006, the HPV vaccine has demonstrated clinical efficacy in both men and women. Several commercially available vaccines now exist, but only one is available in the United States. Both prelicensure and postlicensure studies demonstrate robust safety profiles. HPV vaccines should be made available to everyone between the ages of 9 and 26 years of age. Newer vaccination recommendations in expanded populations rely on patient-provider shared decision making. Currently, available HPV vaccines offer little therapeutic benefit. Recent research has identified several new DNA vaccines and delivery modifications with early demonstrated success at eliminating prevalent HPV infections and precancerous lesions. Despite the success of the HPV vaccine, vaccination hesitancy and disinformation continue to threaten our ability to eliminate these deadly cancers. Informational, behavioral, and environmental interventions have mixed success in increasing vaccination rates, but several strategies do exist to increase rates of vaccination.

The landscape of T cell antigens for cancer immunotherapy

The remarkable capacity of immunotherapies to induce durable regression in some patients with metastatic cancer relies heavily on T cell recognition of tumor-presented antigens. As checkpoint-blockade therapy has limited efficacy, tumor antigens have the potential to be exploited for complementary treatments, many of which are already in clinical trials. The surge of interest in this topic has led to the expansion of the tumor antigen landscape with the emergence of new antigen categories. Nonetheless, how different antigens compare in their ability to elicit efficient and safe clinical responses remains largely unknown. Here, we review known cancer peptide antigens, their attributes and the relevant clinical data and discuss future directions.

Advances in HPV-associated tumor management: Therapeutic strategies and emerging insights

With the rapid increase in the incidence of cervical cancer, anal cancer and other cancers, human papillomavirus (HPV) infection has become a growing concern. Persistent infection with high-risk HPV is a major cause of malignant tumors. In addition, microbiota and viruses such as human immunodeficiency virus, herpes simplex virus, and Epstein-Barr virus are closely associated with HPV infection. The limited effectiveness of existing treatments for HPV-associated tumors and the high rates of recurrence and metastasis in patients create an urgent need for novel and effective approaches. In recent years, HPV vaccine coverage has increased and can reduce the incidence of serious adverse events. Overall, this article provides a comprehensive overview of HPV biology, microbiome, and other viral interactions in cancer development, highlighting the need for a more comprehensive approach to cancer prevention and treatment. Current and emerging HPV-related cancer control and treatment strategies are also further explored.

Outcomes of High-Grade Cervical Dysplasia with Positive Margins and HPV Persistence after Cervical Conization

The objective of this work is to assess the 5-year outcomes of patients undergoing conization for high-grade cervical lesions that simultaneously present as risk factors in the persistence of HPV infection and the positivity of surgical resection margins. This is a retrospective study evaluating patients undergoing conization for high-grade cervical lesions. All patients included had both positive surgical margins and experienced HPV persistence at 6 months. Associations were evaluated with Cox proportional hazard regression and summarized using hazard ratio (HR). The charts of 2966 patients undergoing conization were reviewed. Among the whole population, 163 (5.5%) patients met the inclusion criteria, being at high risk due to the presence of positive surgical margins and experiencing HPV persistence. Of 163 patients included, 17 (10.4%) patients developed a CIN2+ recurrence during the 5-year follow-up. Via univariate analyses, diagnosis of CIN3 instead of CIN2 (HR: 4.88 (95%CI: 1.10, 12.41); p = 0.035) and positive endocervical instead of ectocervical margins (HR: 6.44 (95%CI: 2.80, 9.65); p < 0.001) were associated with increased risk of persistence/recurrence. Via multivariate analyses, only positive endocervical instead of ectocervical margins (HR: 4.56 (95%CI: 1.23, 7.95); p = 0.021) were associated with worse outcomes. In this high-risk group, positive endocervical margins is the main risk factor predicting 5-year recurrence.

Development of therapeutic vaccines for the treatment of diseases

Vaccines are one of the most effective medical interventions to combat newly emerging and re-emerging diseases. Prophylactic vaccines against rabies, measles, etc., have excellent effectiveness in preventing viral infection and associated diseases. However, the host immune response is unable to inhibit virus replication or eradicate established diseases in most infected people. Therapeutic vaccines, expressing specific endogenous or exogenous antigens, mainly induce or boost cell-mediated immunity via provoking cytotoxic T cells or elicit humoral immunity via activating B cells to produce specific antibodies. The ultimate aim of a therapeutic vaccine is to reshape the host immunity for eradicating a disease and establishing lasting memory. Therefore, therapeutic vaccines have been developed for the treatment of some infectious diseases and chronic noncommunicable diseases. Various technological strategies have been implemented for the development of therapeutic vaccines, including molecular-based vaccines (peptide/protein, DNA and mRNA vaccines), vector-based vaccines (bacterial vector vaccines, viral vector vaccines and yeast-based vaccines) and cell-based vaccines (dendritic cell vaccines and genetically modified cell vaccines) as well as combinatorial approaches. This review mainly summarizes therapeutic vaccine-induced immunity and describes the development and status of multiple types of therapeutic vaccines against infectious diseases, such as those caused by HPV, HBV, HIV, HCV, and SARS-CoV-2, and chronic noncommunicable diseases, including cancer, hypertension, Alzheimer's disease, amyotrophic lateral sclerosis, diabetes, and dyslipidemia, that have been evaluated in recent preclinical and clinical studies.

Governing HPV-related carcinoma using vaccines: Bottlenecks and breakthroughs

Human papillomavirus (HPV) contributes to sexually transmitted infection, which is primarily associated with pre-cancerous and cancerous lesions in both men and women and is among the neglected cancerous infections in the world. At global level, two-, four-, and nine-valent pure L1 protein encompassed vaccines in targeting high-risk HPV strains using recombinant DNA technology are available. Therapeutic vaccines are produced by early and late oncoproteins that impart superior cell immunity to preventive vaccines that are under investigation. In the current review, we have not only discussed the clinical significance and importance of both preventive and therapeutic vaccines but also highlighted their dosage and mode of administration. This review is novel in its way and will pave the way for researchers to address the challenges posed by HPV-based vaccines at the present time.

Prophylactic and Therapeutic HPV Vaccines: Current Scenario and Perspectives

Persistent human papillomavirus (HPV) infection is recognized as the main cause of cervical cancer and other malignant cancers. Although early detection and treatment can be achieved by effective HPV screening methods and surgical procedures, the disease load has not been adequately mitigated yet, especially in the underdeveloped areas. Vaccine, being regarded as a more effective solution, is expected to prevent virus infection and the consequent diseases in the phases of both prevention and treatment. Currently, there are three licensed prophylactic vaccines for L1-VLPs, namely bivalent, quadrivalent and nonavalent vaccine. About 90% of HPV infections have been effectively prevented with the implementation of vaccines worldwide. However, no significant therapeutic effect has been observed on the already existed infections and lesions. Therapeutic vaccine designed for oncoprotein E6/E7 activates cellular immunity rather than focuses on neutralizing antibodies, which is considered as an ideal immune method to eliminate infection. In this review, we elaborate on the classification, mechanism, and clinical effects of HPV vaccines for disease prevention and treatment, in order to make improvements to the current situation of HPV vaccines by provoking new ideas.

Review of the Standard and Advanced Screening, Staging Systems and Treatment Modalities for Cervical Cancer

Simple Summary

This review discusses the timeline and development of the recommended screening tests, diagnosis system, and therapeutics implemented in clinics for precancer and cancer of the uterine cervix. The incorporation of the latest automation, machine learning modules, and state-of-the-art technologies into these aspects are also discussed.

Abstract

Cancer arising from the uterine cervix is the fourth most common cause of cancer death among women worldwide. Almost 90% of cervical cancer mortality has occurred in low- and middle-income countries. One of the major aetiologies contributing to cervical cancer is the persistent infection by the cancer-causing types of the human papillomavirus. The disease is preventable if the premalignant lesion is detected early and managed effectively. In this review, we outlined the standard guidelines that have been introduced and implemented worldwide for decades, including the cytology, the HPV detection and genotyping, and the immunostaining of surrogate markers. In addition, the staging system used to classify the premalignancy and malignancy of the uterine cervix, as well as the safety and efficacy of the various treatment modalities in clinical trials for cervical cancers, are also discussed. In this millennial world, the advancements in computer-aided technology, including robotic modules and artificial intelligence (AI), are also incorporated into the screening, diagnostic, and treatment platforms. These innovations reduce the dependence on specialists and technologists, as well as the work burden and time incurred for sample processing. However, concerns over the practicality of these advancements remain, due to the high cost, lack of flexibility, and the judgment of a trained professional that is currently not replaceable by a machine.

Effectiveness and Safety of Therapeutic Vaccines for Precancerous Cervical Lesions: A Systematic Review and Meta-Analysis

OBJECTIVE

This study systematically evaluated the effectiveness and safety of therapeutic vaccines for precancerous cervical lesions, providing evidence for future research.

METHODS

We systematically searched the literature in 10 databases from inception to February 18, 2021. Studies on the effectiveness and safety of therapeutic vaccines for precancerous cervical lesions were included. Then, we calculated the overall incidence rates of four outcomes, for which we used the risk ratio (RR) and 95% confidence interval (95% CI) to describe the effects of high-grade squamous intraepithelial lesions (HSILs) on recurrence.

RESULTS

A total of 39 studies were included, all reported in English, published from 1989 to 2021 in 16 countries. The studies covered 22,865 women aged 15-65 years, with a total of 5,794 vaccinated, and 21 vaccines were divided into six types. Meta-analysis showed that the overall incidence rate of HSIL regression in vaccine therapies was 62.48% [95% CI (42.80, 80.41)], with the highest rate being 72.32% for viral vector vaccines [95% CI (29.33, 99.51)]. Similarly, the overall incidence rates of HPV and HPV16/18 clearance by vaccines were 48.59% [95% CI (32.68, 64.64)] and 47.37% [95% CI (38.00, 56.81)], respectively, with the highest rates being 68.18% [95% CI (45.13, 86.14)] for bacterial vector vaccines and 55.14% [95% CI (42.31, 67.66)] for DNA-based vaccines. In addition, a comprehensive analysis indicated that virus-like particle vaccines after conization reduced the risk of HSIL recurrence with statistical significance compared to conization alone [RR = 0.46; 95% CI (0.29, 0.74)]. Regarding safety, only four studies reported a few severe adverse events, indicating that vaccines for precancerous cervical lesions are generally safe.

CONCLUSION

Virus-like particle vaccines as an adjuvant immunotherapy for conization can significantly reduce the risk of HSIL recurrence. Most therapeutic vaccines have direct therapeutic effects on precancerous lesions, and the effectiveness in HSIL regression, clearance of HPV, and clearance of HPV16/18 is great with good safety. That is, therapeutic vaccines have good development potential and are worthy of further research.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO https://www.crd.york.ac.uk/PROSPERO/, CRD42021275452.

The Efficacy of Therapeutic DNA Vaccines Expressing the Human Papillomavirus E6 and E7 Oncoproteins for Treatment of Cervical Cancer: Systematic Review

Cervical cancer is recognized as a serious public health problem since it remains one of the most common cancers with a high mortality rate among women despite existing preventative, screening, and treatment approaches. Since Human Papillomavirus (HPV) was recognized as the causative agent, the preventative HPV vaccines have made great progress over the last few years. However, people already infected with the virus require an effective treatment that would ensure long-term survival and a cure. Currently, clinical trials investigating HPV therapeutic vaccines show a promising vaccine-induced T-cell mediated immune response, resulting in cervical lesion regression and viral eradication. Among existing vaccine types (live vector, protein-based, nucleic acid-based, etc.), deoxyribonucleic acid (DNA) therapeutic vaccines are the focus of the study, since they are safe, cost-efficient, thermostable, easily produced in high purity and distributed. The aim of this study is to assess and compare existing DNA therapeutic vaccines in phase I and II trials, expressing HPV E6 and E7 oncoproteins for the prospective treatment of cervical cancer based on clinical efficacy, immunogenicity, viral clearance, and side effects. Five different DNA therapeutic vaccines (GX-188E, VGX-3100, pNGVL4a-CRT/E7(detox), pNGVL4a-Sig/E7(detox)/HSP70, MEDI0457) were well-tolerated and clinically effective. Clinical implementation of DNA therapeutic vaccines into treatment regimen as a sole approach or in combination with conservative treatment holds great potential for effective cancer treatment.

In Silico Model Estimates the Clinical Trial Outcome of Cancer Vaccines

Over 30 years after the first cancer vaccine clinical trial (CT), scientists still search the missing link between immunogenicity and clinical responses. A predictor able to estimate the outcome of cancer vaccine CTs would greatly benefit vaccine development. Published results of 94 CTs with 64 therapeutic vaccines were collected. We found that preselection of CT subjects based on a single matching HLA allele does not increase immune response rates (IRR) compared with non-preselected CTs (median 60% vs. 57%, p = 0.4490). A representative in silico model population (MP) comprising HLA-genotyped subjects was used to retrospectively calculate in silico IRRs of CTs based on the percentage of MP-subjects having epitope(s) predicted to bind ≥ 1–4 autologous HLA allele(s). We found that in vitro measured IRRs correlated with the frequency of predicted multiple autologous allele-binding epitopes (AUC 0.63–0.79). Subgroup analysis of multi-antigen targeting vaccine CTs revealed correlation between clinical response rates (CRRs) and predicted multi-epitope IRRs when HLA threshold was ≥ 3 (r = 0.7463, p = 0.0004) but not for single HLA allele-binding epitopes (r = 0.2865, p = 0.2491). Our results suggest that CRR depends on the induction of broad T-cell responses and both IRR and CRR can be predicted when epitopes binding to multiple autologous HLAs are considered.

A New Generation of Vaccines in the Age of Immunotherapy

PURPOSE OF REVIEW

Cancer vaccines are one of the most extensively studied immunotherapy type in solid tumors. Despite favorable presuppositions, so far, the use of cancer vaccines has been associated with disappointing results. However, a new generation of vaccines has been developed, promising to revolutionize the immunotherapy field.

RECENT FINDINGS

In this review, we aim to highlight the advances in cancer vaccines and the remaining hurdles to overcome. Cancer vaccination has experienced tremendous progress in the last decade, with myriad promising developments. Future efforts should focus on optimization of target identification, streamlining of most appropriate vaccination strategies, and adjuvant development, as well as predictive biomarker identification. Cautious optimism is warranted in the face of early successes seen in recent clinical trials for oncolytic vaccines. If an approach were to prove successful, it could revolutionize cancer therapy the way ICIs did in the previous decade.

Physiopathology and effectiveness of therapeutic vaccines against human papillomavirus

Human papillomavirus (HPV) is a well-known sexually transmitted disorder globally. Human papillomavirus (HPV) is the 3rd most common cancer that causes cervical carcinoma, and globally it accounts for 275,000 deaths every year. The load of HPV-associated abrasions can be lessened through vaccination. At present, three forms of prophylactic vaccines, Cervarix, Gadrasil, and Gardasil 9, are commercially accessible but all these prophylactic vaccines have not the ability to manage and control developed abrasions or infections. Therefore, a considerable amount of the population is not secured from HPV infectivity. Consequently, the development of therapeutic HPV vaccines is a crucial requirement of this era, for the treatment of persisting infections, and to stop the progression of HPV-associated cancers. Therapeutic vaccines are a developing trial approach. Because of the constitutive expression of E6 and E7 early genes in cancerous and pre-cancerous tissues, and their involvement in disturbance of the cell cycle, these are best targets for this therapeutic vaccine treatment. For the synthesis and development of therapeutic vaccines, various approaches have been examined comprising cell-based vaccines, peptide/protein-based vaccines, nucleic acid-based vaccines, and live-vector vaccines all proceeding towards clinical trials. This review emphasizes the development, progress, current status, and future perspective of several vaccines for the cure of HPV-related abrasions and cancers. This review also provides an insight to assess the effectiveness, safety, efficacy, and immunogenicity of therapeutic vaccines in the cure of patients infected with HPV-associated cervical cancer.

Nanomedicine-mediated optimization of immunotherapeutic approaches in cervical cancer

Cervical cancer shows immense complexity at the epigenetic, genetic and cellular levels, limiting conventional treatment. Immunotherapy has revolutionized nanomedicine and rejuvenated the field of tumor immunology. Although several immunotherapeutic approaches have shown favorable clinical responses, their efficacies vary, with subsets of patients benefitting. The success of cancer immunotherapy requires the enhancement of cytokines and antitumor effector cell production and activation. Recently, the feasibility of nanoparticle-based cytokine approaches in tumor immunotherapy has been highlighted. Immunotherapeutic nanoparticle-based platforms form a novel strategy enabling researchers to co-deliver immunomodulatory agents, target tumors, improve pharmacokinetics and minimize collateral toxicity to healthy cells. This review looks at the potential of immunotherapy and nanotechnologically enhanced immunotherapeutic approaches for cervical cancer.

Targeting E7 antigen to the endoplasmic reticulum degradation pathway promotes a potent therapeutic antitumor effect

It has been previously reported that targeting and retaining antigens in the endoplasmic reticulum (ER) can induce an ER stress response. In this study, we evaluated the antitumor effect of E7 antigen fused to an ERresident protein, cyclooxygenase-2, which possesses a 19-aminoacid cassette that directs it to the endoplasmic reticulum-associated protein degradation (ERAD) pathway. The featured DNA constructs, COX2-E7 and COX2-E7ΔERAD, with a deletion in the 19-aminoacid cassette, were used to evaluate the importance of this sequence. In vitro analysis of protein expression and ER localisation were verified. We observed that both constructs induced an ER stress response. This finding correlated with the antitumor effect in mice injected with TC-1 cells and treated with different DNA constructs by biolistic vaccination. Immunisation with COX2-E7 and COX2-E7ΔERAD DNA constructs induced a significant antitumor effect in mice, without a significant difference between them, although the COX2-E7 construct induced a significant E7-specific immune response. These results demonstrate that targeting the E7 antigen to the ERAD pathway promotes a potent therapeutic antitumor effect. This strategy could be useful for the design of other antigen-specific therapies.

Cervical Cancer Immunotherapy: Facts and Hopes

It is a sad fact that despite being almost completely preventable through human papillomavirus (HPV) vaccination and screening, cervical cancer remains the fourth most common cancer to affect women worldwide. Persistent high-risk HPV (hrHPV) infection is the primary etiologic factor for cervical cancer. Upward of 70% of cases are driven by HPV types 16 and 18, with a dozen other hrHPVs associated with the remainder of cases. Current standard-of-care treatments include radiotherapy, chemotherapy, and/or surgical resection. However, they have significant side effects and limited efficacy against advanced disease. There are a few treatment options for recurrent or metastatic cases. Immunotherapy offers new hope, as demonstrated by the recent approval of programmed cell death protein 1-blocking antibody for recurrent or metastatic disease. This might be augmented by combination with antigen-specific immunotherapy approaches, such as vaccines or adoptive cell transfer, to enhance the host cellular immune response targeting HPV-positive cancer cells. As cervical cancer progresses, it can foster an immunosuppressive microenvironment and counteract host anticancer immunity. Thus, approaches to reverse suppressive immune environments and bolster effector T-cell functioning are likely to enhance the success of such cervical cancer immunotherapy. The success of nonspecific immunostimulants like imiquimod against genital warts also suggest the possibility of utilizing these immunotherapeutic strategies in cervical cancer prevention to treat precursor lesions (cervical intraepithelial neoplasia) and persistent hrHPV infections against which the licensed prophylactic HPV vaccines have no efficacy. Here, we review the progress and challenges in the development of immunotherapeutic approaches for the prevention and treatment of cervical cancer.

Cationic Nanoparticle-Based Cancer Vaccines

Cationic nanoparticles have been shown to be surprisingly effective as cancer vaccine vehicles in preclinical and clinical studies. Cationic nanoparticles deliver tumor-associated antigens to dendritic cells and induce immune activation, resulting in strong antigen-specific cellular immune responses, as shown for a wide variety of vaccine candidates. In this review, we discuss the relation between the cationic nature of nanoparticles and the efficacy of cancer immunotherapy. Multiple types of lipid- and polymer-based cationic nanoparticulate cancer vaccines with various antigen types (e.g., mRNA, DNA, peptides and proteins) and adjuvants are described. Furthermore, we focus on the types of cationic nanoparticles used for T-cell induction, especially in the context of therapeutic cancer vaccination. We discuss different cationic nanoparticulate vaccines, molecular mechanisms of adjuvanticity and biodistribution profiles upon administration via different routes. Finally, we discuss the perspectives of cationic nanoparticulate vaccines for improving immunotherapy of cancer.

Development of DNA Vaccine Targeting E6 and E7 Proteins of Human Papillomavirus 16 (HPV16) and HPV18 for Immunotherapy in Combination with Recombinant Vaccinia Boost and PD-1 Antibody

Immunotherapy for cervical cancer should target high-risk human papillomavirus types 16 and 18, which cause 50% and 20% of cervical cancers, respectively. Here, we describe the construction and characterization of the pBI-11 DNA vaccine via the addition of codon-optimized human papillomavirus 18 (HPV18) E7 and HPV16 and 18 E6 genes to the HPV16 E7-targeted DNA vaccine pNGVL4a-SigE7(detox)HSP70 (DNA vaccine pBI-1). Codon optimization of the HPV16/18 E6/E7 genes in pBI-11 improved fusion protein expression compared to that in DNA vaccine pBI-10.1 that utilized the native viral sequences fused 3' to a signal sequence and 5' to the HSP70 gene of Mycobacterium tuberculosis Intramuscular vaccination of mice with pBI-11 DNA better induced HPV antigen-specific CD8+ T cell immune responses than pBI-10.1 DNA. Furthermore, intramuscular vaccination with pBI-11 DNA generated stronger therapeutic responses for C57BL/6 mice bearing HPV16 E6/E7-expressing TC-1 tumors. The HPV16/18 antigen-specific T cell-mediated immune responses generated by pBI-11 DNA vaccination were further enhanced by boosting with tissue-antigen HPV vaccine (TA-HPV). Combination of the pBI-11 DNA and TA-HPV boost vaccination with PD-1 antibody blockade significantly improved the control of TC-1 tumors and extended the survival of the mice. Finally, repeat vaccination with clinical-grade pBI-11 with or without clinical-grade TA-HPV was well tolerated in vaccinated mice. These preclinical studies suggest that the pBI-11 DNA vaccine may be used with TA-HPV in a heterologous prime-boost strategy to enhance HPV 16/18 E6/E7-specific CD8+ T cell responses, either alone or in combination with immune checkpoint blockade, to control HPV16/18-associated tumors. Our data serve as an important foundation for future clinical translation.IMPORTANCE Persistent expression of high-risk human papillomavirus (HPV) E6 and E7 is an obligate driver for several human malignancies, including cervical cancer, wherein HPV16 and HPV18 are the most common types. PD-1 antibody immunotherapy helps a subset of cervical cancer patients, and its efficacy might be improved by combination with active vaccination against E6 and/or E7. For patients with HPV16+ cervical intraepithelial neoplasia grade 2/3 (CIN2/3), the precursor of cervical cancer, intramuscular vaccination with a DNA vaccine targeting HPV16 E7 and then a recombinant vaccinia virus expressing HPV16/18 E6-E7 fusion proteins (TA-HPV) was safe, and half of the patients cleared their lesions in a small study (NCT00788164). Here, we sought to improve upon this therapeutic approach by developing a new DNA vaccine that targets E6 and E7 of HPV16 and HPV18 for administration prior to a TA-HPV booster vaccination and for application against cervical cancer in combination with a PD-1-blocking antibody.

Vaccination Strategies for the Control and Treatment of HPV Infection and HPV-Associated Cancer

Human papillomavirus (HPV) is the most common sexually transmitted infection, currently affecting close to 80 million Americans. Importantly, HPV infection is recognized as the etiologic factor for numerous cancers, including cervical, vulval, vaginal, penile, anal, and a subset of oropharyngeal cancers. The prevalence of HPV infection and its associated diseases are a significant problem, affecting millions of individuals worldwide. Likewise, the incidence of HPV infection poses a significant burden on individuals and the broader healthcare system. Between 2011 and 2015, there were an estimated 42,700 new cases of HPV-associated cancers each year in the United States alone. Similarly, the global burden of HPV is high, with around 630,000 new cases of HPV-associated cancer occurring each year. In the last decade, a total of three preventive major capsid protein (L1) virus-like particle-based HPV vaccines have been licensed and brought to market as a means to prevent the spread of HPV infection. These prophylactic vaccines have been demonstrated to be safe and efficacious in preventing HPV infection. The most recent iteration of the preventive HPV vaccine, a nanovalent, L1-VLP vaccine, protects against a total of nine HPV types (seven high-risk and two low-risk HPV types), including the high-risk types HPV16 and HPV18, which are responsible for causing the majority of HPV-associated cancers. Although current prophylactic HPV vaccines have demonstrated huge success in preventing infection, existing barriers to vaccine acquisition have limited their widespread use, especially in low- and middle-income countries, where the burden of HPV-associated diseases is highest. Prophylactic vaccines are unable to provide protection to individuals with existing HPV infections or HPV-associated diseases. Instead, therapeutic HPV vaccines capable of generating T cell-mediated immunity against HPV infection and associated diseases are needed to ameliorate the burden of disease in individuals with existing HPV infection. To generate a cell-mediated immune response against HPV, most therapeutic vaccines target HPV oncoproteins E6 and E7. Several types of therapeutic HPV vaccine candidates have been developed including live-vector, protein, peptide, dendritic cell, and DNA-based vaccines. This chapter will review the commercially available prophylactic HPV vaccines and discuss the recent progress in the development of therapeutic HPV vaccines.

Therapeutic DNA Vaccine Against HPV16-Associated Cancer

Human papillomavirus (HPV) is a contagious cause of anogenital and oropharyngeal cancers developing from persistently infected and subsequently transformed basal keratinocytes of mucosal epithelium. DNA-based immunotherapy offers great potential for the treatment of persisting HPV infections and associated cancers. Preclinical testing of therapeutic DNA-based HPV-targeted immunotherapy requires robust animal models which mimic HPV-associated cancer disease in humans. Here we describe a detailed protocol of intradermal delivery of a therapeutic DNA vaccine and a grafting model of neoantigen expressing skin to evaluate vaccine efficacy against HPV16 mediated hyperproliferative epithelium in mice.

Recent developments in immunotherapy of cancers caused by human papillomaviruses

A subset of oncogenic human papillomaviruses (HPVs) is the main cause of genital cancers, most importantly cervical cancer and an increasing number of head and neck cancers. Despite the availability of prophylactic vaccines against the most prevalent oncogenic HPV types, HPV‐induced malignancies are still a major health and economic burden. Besides conventional treatment with surgery, chemotherapy and radiation, immunotherapy is emerging as an efficient adjuvant option. Here, we review relevant studies and ongoing clinical trials using immune checkpoint inhibitors, therapeutic vaccines, gene editing approaches and adoptive T cell therapies, with special focus on engineered TCR T cells, which are showing encouraging results and could lead to significant improvement in the treatment of HPV+‐infected cancer patients.

Checkpoint Inhibitors in Gynecological Malignancies: Are we There Yet?

The emergence of immune checkpoint inhibitors (ICIs) has revolutionized the field of oncology. For many cancer types, treatment paradigms have changed, as immunotherapy is increasingly being integrated into frontline standard-of-care treatments and producing meaningful and prolonged responses. This has inspired an avalanche of clinical trials studying ICIs in all types of malignancies, including gynecological cancers. Ovarian and endometrial cancers are characterized by DNA damage repair defects, either via disruption of the homologous recombination DNA repair mechanism in the former or via defects in the mismatch repair (MMR) pathway in the latter, which lead to a high load of neoantigens in both. Cervical cancer is dependent on the expression of human papillomavirus (HPV) proteins, which induce an immune response. Regardless, clinical trials testing ICIs in gynecological malignancies have initially led to disappointing results. Despite durable responses in some patients, overall response rates have been dismal. Nevertheless, in recent years, with the development of better predictive tumor biomarkers, such as microsatellite instability for endometrial cancer and programmed death ligand 1 for cervical cancer, ICIs have found their way into routine treatments for patients with advanced-stage disease. ICI-based combinations, although adding toxicity, have further improved response rates, and new combinations are currently being tested in clinical trials, as are other immunotherapy modalities, such as adoptive cell transfer and HPV-based vaccines. This review summarizes current clinical evidence supporting the use of immunotherapy in gynecological malignancies and describes studies in progress, with a focus on ICIs and predictive response biomarkers.

Nucleic Acid-Based Approaches for Tumor Therapy

Within the last decade, the introduction of checkpoint inhibitors proposed to boost the patients' anti-tumor immune response has proven the efficacy of immunotherapeutic approaches for tumor therapy. Furthermore, especially in the context of the development of biocompatible, cell type targeting nano-carriers, nucleic acid-based drugs aimed to initiate and to enhance anti-tumor responses have come of age. This review intends to provide a comprehensive overview of the current state of the therapeutic use of nucleic acids for cancer treatment on various levels, comprising (i) mRNA and DNA-based vaccines to be expressed by antigen presenting cells evoking sustained anti-tumor T cell responses, (ii) molecular adjuvants, (iii) strategies to inhibit/reprogram tumor-induced regulatory immune cells e.g., by RNA interference (RNAi), (iv) genetically tailored T cells and natural killer cells to directly recognize tumor antigens, and (v) killing of tumor cells, and reprograming of constituents of the tumor microenvironment by gene transfer and RNAi. Aside from further improvements of individual nucleic acid-based drugs, the major perspective for successful cancer therapy will be combination treatments employing conventional regimens as well as immunotherapeutics like checkpoint inhibitors and nucleic acid-based drugs, each acting on several levels to adequately counter-act tumor immune evasion.

Adjuvant Human Papillomavirus Vaccine to Reduce Recurrent Cervical Dysplasia in Unvaccinated Women: A Systematic Review and Meta-analysis

OBJECTIVE

To perform a systematic review and meta-analysis evaluating the efficacy of adjuvant human papillomavirus (HPV) vaccination in preventing recurrent cervical intraepithelial neoplasia (CIN) 2 or greater after surgical excision.

DATA SOURCES

Electronic databases (Cochrane, PubMed, EMBASE, MEDLINE, Scopus, and ClinicalTrials.gov) were searched for studies comparing surgical excision alone to surgical excision with adjuvant HPV vaccination for CIN 2 or greater. Studies published from January 1990 to January 2019 were included.

METHODS

A total of 5,901 studies were reviewed. The primary outcomes evaluated included: recurrence of CIN 2 or greater, CIN 1 or greater, and HPV 16,18 associated CIN within 6-48 months. We used Covidence software to assist with screening, and meta-analysis was performed using Review Manager.

TABULATION, INTEGRATION, AND RESULTS

Six studies met inclusion criteria and were included in the final analysis. In total 2,984 women were included; 1,360 (45.6%) received adjuvant HPV vaccination after surgical excision, and 1,624 (54.4%) received either placebo or surgical management alone for CIN 2 or greater. Recurrence of CIN 2 or greater occurred within 6-48 months in 115 women (3.9%) overall; however, recurrence was significantly lower for vaccinated women: 26 of 1,360 women (1.9%) vs 89 of 1,624 unvaccinated women (5.9%) (relative risk [RR] 0.36 95% CI 0.23-0.55). The risk of CIN 1 or greater was also significantly lower with adjuvant HPV vaccination, occurring in 86 of 1,360 vaccinated women (6.3%) vs 157 of 1,624 unvaccinated women (9.7%) (RR 0.67 95% CI 0.52-0.85). Thirty-five women developed recurrent CIN 2 or greater lesions specific to HPV 16,18; nine received adjuvant vaccination (0.9%) vs 26 who were unvaccinated (2.0%) (RR 0.41 95% CI 0.20-0.85).

CONCLUSION

Adjuvant HPV vaccination in the setting of surgical excision for CIN 2 or greater is associated with a reduced risk of recurrent cervical dysplasia overall and a reduction in the risk of recurrent lesions caused by the most oncogenic strains (HPV 16,18). Human papillomavirus vaccination should therefore be considered for adjuvant treatment in patients undergoing surgical excision for CIN 2 or greater.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42019123786.

Advances in immunotherapy for cervical cancer

PURPOSE OF REVIEW

Novel therapies are needed for the treatment of recurrent cervical cancer. The best chemotherapy regimen to date has a response rate of 48% with an overall survival of 17 months, with limited options for second-line chemotherapy. Immunotherapy can induce a strong immune response in cervical cancer due to retained viral antigens and is reviewed in this article.

RECENT FINDINGS

Current clinical trials include treatment with Listeria that elicits an immune response against the E7 oncoprotein and active vaccines against the E7 oncoprotein. Although the response rates to programmed cell death 1 (PD-1) inhibition alone have been modest, the landmark survival reported in these trials suggests the activity of these agents may not be measured by RECIST criteria. The KEYNOTE-158 trial has led to the approval of pembrolizumab in recurrent programmed cell death ligand 1 (PD-L1) positive cervical cancer. Combinations of programmed cell death 1 and anticytotoxic T-lymphocyte-associated protein 4 inhibitors (CTLA4) inhibitors have shown promising and durable activity. There is active research with new combinations of checkpoint inhibitors, as well as combinations of these drugs with chemotherapy and radiation, and other novel approaches.

SUMMARY

Immune therapy has broad activity in cervical cancer. Responses to immunotherapy can be dramatic and durable. Continued work to find the optimal combination and setting for immunotherapy is ongoing.

Human Papillomavirus Vaccines: An Updated Review

Human papillomavirus (HPV) vaccines, which were introduced in many countries in the past decade, have shown promising results in decreasing HPV infection and related diseases, such as warts and precancerous lesions. In this review, we present the updated information about current HPV vaccines, focusing on vaccine coverage and efficacy. In addition, pan-gender vaccination and current clinical trials are also discussed. Currently, more efforts should be put into increasing the vaccine’s coverage, especially in low- and middle-income countries. Provision of education on HPV and vaccination is one of the most important methods to achieve this. Vaccines that target HPV types not included in current vaccines are the next stage in vaccine development. In the future, all HPV-related cancers, such as head and neck cancer, and anal cancer, should be tracked and evaluated, especially in countries that have introduced pan-gender vaccination programs. Therapeutic vaccines, in combination with other cancer treatments, should continue to be investigated.

Nomogram-based prediction of cervical dysplasia persistence/recurrence

The widespread introduction of screening methods allow to identify cervical dysplasia before having invasive cancer. The risk of developing cervical dysplasia persistence/ recurrence following conization represent a major health issue. Although several studies tried to identify predictors for cervical dysplasia persistence/recurrence, no previous study has been conducted to develop a risk calculator. The current study aimed to identify predictors of cervical dysplasia persistence/recurrence among women undergoing primary conization. We aimed to build nomograms estimating the risk of developing cervical dysplasia recurrence. Data of consecutive women with diagnosis of high-risk human papillomavirus (HPV) undergoing conization were retrospectively evaluated (1503 patients). The risk of developing cervical dysplasia persistence/recurrence was assessed with Kaplan-Meier and Cox's hazard models. Additionally, two nomograms were built to estimate likelihood of cervical dysplasia recurrence: the first based on baseline and operative parameters and the second focusing on type-specific HPV detected. The performance of the above nomograms was assessed using concordance index. A total of 1503 patients were analyzed. After a mean (SD) follow-up of 48.6 ( ± 17.5) months, 84 (5.6%) patients required secondary conization. By multivariate analysis, HIV infection [hazard ratio (HR): 7.78; 95% confidence interval (CI): 2.77-21.81; P < 0.001], positive margins (HR: 26.2; 95% CI: 14.1-48.71; P < 0.001) and persistence of HPV (HR: 6.82; 95% CI: 4.15-11.21; P < 0.001) correlated with cervical intraepithelial neoplasia 2+ persistence/recurrence. The importance of those variables was corroborated by our first nomogram. The second nomogram suggested the impact of type-specific HPV infection in predicting cervical dysplasia persistence/ recurrence. HPV16, HPV18, HPV33, HPV35 and HPV45 were the HPV types most commonly associated with cervical dysplasia persistence/recurrence. The concordance index was greater than 0.70 for both nomograms, thus suggesting the reproducibility of our models. We developed the first two nomograms predicting this risk. The findings of this study require external validation. Once validated our data might be useful to plan a tailored postoperative surveillance of women receiving primary conization.

Expression of the Reverse Transcriptase Domain of Telomerase Reverse Transcriptase Induces Lytic Cellular Response in DNA-Immunized Mice and Limits Tumorigenic and Metastatic Potential of Murine Adenocarcinoma 4T1 Cells

Telomerase reverse transcriptase (TERT) is a classic tumor-associated antigen overexpressed in majority of tumors. Several TERT-based cancer vaccines are currently in clinical trials, but immune correlates of their antitumor activity remain largely unknown. Here, we characterized fine specificity and lytic potential of immune response against rat TERT in mice. BALB/c mice were primed with plasmids encoding expression-optimized hemagglutinin-tagged or nontagged TERT or empty vector and boosted with same DNA mixed with plasmid encoding firefly luciferase (Luc DNA). Injections were followed by electroporation. Photon emission from booster sites was assessed by in vivo bioluminescent imaging. Two weeks post boost, mice were sacrificed and assessed for IFN-γ, interleukin-2 (IL-2), and tumor necrosis factor alpha (TNF-α) production by T-cells upon their stimulation with TERT peptides and for anti-TERT antibodies. All TERT DNA-immunized mice developed cellular and antibody response against epitopes at the N-terminus and reverse transcriptase domain (rtTERT) of TERT. Photon emission from mice boosted with TERT/TERT-HA+Luc DNA was 100 times lower than from vector+Luc DNA-boosted controls. Bioluminescence loss correlated with percent of IFN-γ/IL-2/TNF-α producing CD8+ and CD4+ T-cells specific to rtTERT, indicating immune clearance of TERT/Luc-coexpressing cells. We made murine adenocarcinoma 4T1luc2 cells to express rtTERT by lentiviral transduction. Expression of rtTERT significantly reduced the capacity of 4T1luc2 to form tumors and metastasize in mice, while not affecting in vitro growth. Mice which rejected the tumors developed T-cell response against rtTERT and low/no response to the autoepitope of TERT. This advances rtTERT as key component of TERT-based therapeutic vaccines against cancer.

Targeted Gene Delivery Therapies for Cervical Cancer

Despite being largely preventable through early vaccination and screening strategies, cervical cancer is the most common type of gynecological malignancy worldwide and constitutes one of the leading causes of cancer deaths in women. Patients with advanced or recurrent disease have a very poor prognosis; hence, novel therapeutic modalities to improve clinical outcomes in cervical malignancy are needed. In this regard, targeted gene delivery therapy is presented as a promising approach, which leads to the development of multiple strategies focused on different aspects. These range from altered gene restoration, immune system potentiation, and oncolytic virotherapy to the use of nanotechnology and the design of improved and enhanced gene delivery systems, among others. In the present manuscript, we review the current progress made in targeted gene delivery therapy for cervical cancer, the advantages and drawbacks and their clinical application. At present, multiple targeted gene delivery systems have been reported with encouraging preclinical results. However, the translation to humans has not yet shown a significant clinical benefit due principally to the lack of efficient vectors. Real efforts are being made to develop new gene delivery systems, to improve tumor targeting and to minimize toxicity in normal tissues.

Advances in therapeutic vaccines for treating human papillomavirus-related cervical intraepithelial neoplasia

AIM

Human papillomavirus (HPV) is the etiologic agent of the majority of cervical intraepithelial lesions (CIN) and cervical cancers. While prophylactic HPV vaccines prevent infections from the main high-risk HPV types associated with cervical cancer, alternative nonsurgical and nonablative therapeutics to treat HPV infection and preinvasive HPV diseases have been experimentally investigated. Therapeutic vaccines are an emerging investigational strategy. This review aims to introduce the results of the main clinical trials on the use of therapeutic vaccines for treating HPV infection and -related CIN, reporting the ongoing studies on this field.

METHODS

Data research was conducted using MEDLINE, EMBASE, Web of Sciences, Scopus, ClinicalTrial.gov, OVID and Cochrane Library querying for all articles related to therapeutic vaccines for the treatment of HPV-related CIN. Selection criteria included randomized clinical trials, nonrandomized controlled studies and review articles.

RESULTS

Preliminary data are available on the evaluation of therapeutic vaccines for treating cervical HPV infections and CIN. Despite having in vitro demonstrated to obtain humoral and cytotoxic responses, therapeutic vaccines have not yet clinically demonstrated consistent success; moreover, each class of therapeutic vaccines has advantages and limitations. Early clinical data are available in the literature for these compounds, except for MVA E2, which reached the phase III clinical trial status, obtaining positive clinical outcomes.

CONCLUSION

Despite promising results, to date many obstacles are still present before hypothesize an introduction in the clinical practice within the next years. Further studies will draw a definitive conclusion on the role of therapeutic vaccines in this setting.

Perspectives in HPV Secondary Screening and Personalized Therapy Basing on Our Understanding of HPV-Related Carcinogenesis Pathways

As cervical cancer is one of the most common malignancies in women worldwide even with present screening methods, the incidence in most developed countries is not decreasing for the last 15-20 years. A shift has been observed in the age of diagnosis in favour of younger women, and treatment of already developed cervical cancer is a challenge for surgeons. It is imperative to find new diagnostic methods for accurately pointing out patients at high risk of developing malignant disease and developing personalized treatment. Since cervical cancer is almost exclusively associated with HPV infection, understanding changes happening in an infected cell may prove invaluable for search of such methods, but it may also prove helpful in the diagnosis and treatment of other anogenital and nasopharyngeal region cancers. This review follows HPV-related changes in infected cell biology to point what potential markers and targets for therapy are in option when dealing with HPV-related diseases.

Immunotherapy for Gynecologic Cancer: Current Applications and Future Directions

The role of the immune system in the development of cancer has been a subject of ongoing clinical investigation in recent years. Emerging data demonstrate that tumorigenesis resulting in ovarian, uterine, and cervical cancers is a consequence of impaired host immune responses to cancerous cells. Leveraging the immune system through the use of immune checkpoint inhibitors, therapeutic vaccine therapy, and adoptive cell transfer presents a profound opportunity to revolutionize cancer treatment. This review will encompass the role of the immune system in development of gynecologic cancers and highlight recent data regarding immunotherapy applications in ovarian, uterine, and cervical cancers.

Therapeutic Vaccines for HPV-Associated Malignancies

Human papillomavirus (HPV)-related malignancies are responsible for almost all cases of cervical cancer in women, and over 50% of all cases of head and neck carcinoma. Worldwide, HPV-positive malignancies account for 4.5% of the global cancer burden, or over 600,000 cases per year. HPV infection is a pressing public health issue, as more than 80% of all individuals have been exposed to HPV by age 50, representing an important target for vaccine development to reduce the incidence of cancer and the economic cost of HPV-related health issues. The approval of Gardasil^® as a prophylactic vaccine for high-risk HPV 16 and 18 and low-risk HPV6 and 11 for people aged 11-26 in 2006, and of Cervarix^® in 2009, revolutionized the field and has since reduced HPV infection in young populations. Unfortunately, prophylactic vaccination does not induce immunity in those with established HPV infections or HPV-induced neoplasms, and there are currently no therapeutic HPV vaccines approved by the US Food and Drug Administration. This comprehensive review will detail the progress made in the development of therapeutic vaccines against high-risk HPV types, and potential combinations with other immunotherapeutic agents for more efficient and rational designs of combination treatments for HPV-associated malignancies.

Current status of therapeutic HPV vaccines

The accumulating successes of immune-based treatments for solid tumors have prompted an explosion of cancer clinical trials testing strategies to elicit tumor-specific immune effector responses, either alone, in combination with immune checkpoint blockade, or with conventional cancer treatment modalities. However, across the board, clinical responses have been achieved in only a limited subset of cancer patients, underscoring a critical need to identify mechanisms and biomarkers of response, as well as mechanisms of resistance to therapy. Cancers caused by human papillomavirus (HPV) are driven by two viral oncoproteins, E6 and E7, both of which are functionally required for cellular transformation, thereby providing non-'self', tumor-specific antigenic targets. Immune responses that are specific for either or both of these oncoproteins can be used to follow the magnitude and kinetics of immune responses to therapeutic interventions. Moreover, identifying neoantigens is not a concern in early-stage disease - since HPV cancers are driven by HPV oncoproteins, the somatic mutational load in early disease is low, particularly in comparison to non-HPV-related squamous cancers arising in the same organ site [1,2]. Cancers caused by HPV are a model clinical setting in which to test principles of immunotherapies, and to discover mechanisms of interactions between tumors and their attendant immune milieu. In this review, we will use examples of insights gained from studies of HPV disease to illustrate major themes of immune-based therapeutic strategies.

Immune responses to a HSV-2 polynucleotide immunotherapy COR-1 in HSV-2 positive subjects: A randomized double blinded phase I/IIa trial

Background

Genital herpes simplex infection affects more than 500 million people worldwide. We have previously shown that COR-1, a therapeutic HSV-2 polynucleotide vaccine candidate, is safe and well tolerated in healthy subjects.

Objective

Here, we present a single center double-blind placebo-controlled, randomized phase I/IIa trial of COR-1 in HSV-2 positive subjects in which we assessed safety and tolerability as primary endpoints, and immunogenicity and therapeutic efficacy as exploratory endpoints.

Methods

Forty-four HSV-2+ subjects confirmed by positive serology or pathology, and positive qPCR during baseline shedding, with a recurrent genital HSV-2 history of at least 12 months including three to nine reported lesions in 12 months prior to screening, aged 18 to 50 years females and males with given written informed consent, were randomized into two groups. Three immunizations at 4-week intervals and one booster immunization at 6 months, each of 1 mg COR-1 DNA or placebo, were administered intradermally as two injections of 500 μg each to either one forearm or both forearms.

Results

No serious adverse events, life-threatening events or deaths occurred throughout the study. As expected, HSV-2 infected subjects displayed gD2-specific antibody titers prior to immunization. COR-1 was associated with a reduction in viral shedding after booster administration compared with baseline.

Conclusions

This study confirms the previously demonstrated safety of COR-1 in humans and indicates a potential for use of COR-1 as a therapy to reduce viral shedding in HSV-2 infected subjects.

Therapeutic Vaccines Against Human Papilloma Viruses: Achievements and Prospects

Human papillomaviruses of high carcinogenic risk (HR HPVs) are major etiological agents of malignant diseases of the cervix, vulva, penis, anal canal, larynx, head, and neck. Prophylactic vaccination against HPV, which mainly covers girls and women under 25, does not prevent vertical and horizontal HPV transmission in infants and children and does not have a therapeutic effect. As a result, a significant proportion of the population is not protected from the HPV infection and development of HPV-associated neoplastic transformation and cancer, which indicates the need for development and introduction of therapeutic HPV vaccines. Unlike prophylactic vaccines aimed at the formation of virus-neutralizing antibodies, therapeutic vaccines elicit cellular immune response leading to the elimination of infected and malignant cells expressing viral proteins. The ideal targets for vaccine immunotherapy are highly conserved HR HPV oncoproteins E6 and E7 expressed in precancerous and tumor tissues. Here, we describe expression of these proteins during different stages of HPV infection, their antigenic and immunogenic properties, and T-cell epitopes, the response to which correlates with natural regression of HPV-induced neoplastic changes. The review describes patterns of E6 and E7 oncoproteins presentation to the immune system as components of candidate vaccines along with the results of the most promising preclinical trials and animal models used in these trials. Special attention is paid to vaccine candidates which have shown efficacy in clinical trials in patients with HPV-associated neoplastic changes.

Complementary approaches to study NKT cells in cancer

NKT cells are a small but influential member of the T cell family, recognizing lipids presented by the non-classical MHC-like molecule CD1d rather than peptides presented by classical MHC molecules. They bridge between the innate and adaptive immune systems, serving as rapid responders but also allowing the T cell immune system to recognize lipid antigens, for example derived from tumors or bacteria. They also serve as potent regulatory cells, controlling other immune responses. Type I NKT cells use a semi-invariant T cell receptor (TCR) whereas type II use diverse TCRs. Most often, type I NKT cells promote tumor immunity whereas type II tend to suppress it, and the two subtypes crossregulate each other, forming an immunoregulatory axis. Lack of tools to study these important cells has limited the understanding of these, but newer tools have allowed great advances, especially in mouse models. These range from transgenic and knock-out mice to CD1d tetramers carrying ligands for type I or II NKT cells, to antibodies and NKT cell hybridomas. Here we describe these complementary tools and approaches and their use to study NKT cells and their role in the immunology and immunotherapy of cancer.