Human Papillomavirus Vaccine

Knowledge of Human Papillomavirus (HPV), Attitudes, and Practices Towards Anti-HPV Vaccination Among Israeli Nurses

Human papillomavirus (HPV) is a small, non-enveloped, double-stranded DNA virus, belonging to the family of Papillomaviridae. It is a highly common infectious agent, which causes one of the most widespread sexually transmitted infections (STIs), involving approximately 20% of sexually active female adolescents and up to 80% of female adults aged 50 years. There exist two major preventative strategies: namely, anti-HPV vaccination and cervical screening. Healthcare providers, including nurses, can play a crucial role in HPV immunization campaigns, counteracting vaccine hesitancy and doing advocacy and counseling. To explore the overall knowledge of HPV and HPV-related issues, as well as the attitudes and practices of Israeli nurses, a modified and adapted, previously validated knowledge, attitudes, and practices (KAP) questionnaire was administered to a sample of 565 participants, 481 female (85.1%) and 84 male (14.9%). Most of them were married (n = 428, 75.8%), with more than 5 years of experience (n = 405, 71.7%), working in the general/internal medicine ward (n = 432, 76.5%), and Jewish (n = 352, 62.3%). Only 87 nurses (15.4%) got vaccinated against HPV. Forty-four (9.1%) of the female nurses never underwent a Pap smear. Higher percentages of right replies were reported only for the item related to available preventative strategies for cervical cancer (82.1% versus 17.9%). Higher percentages of wrong replies were reported for items related to body regions that can be infected by HPV (60.5% versus 39.5%), percentage of girls aged 15-18 years being sexually active (68.0% versus 32.0%). Similar percentages of right and wrong replies were reported for items related to whom the Pap test is recommended (52.7% versus 47.3%), Israeli Ministry of Health's guidelines for anti-HPV vaccination (50.4% versus 49.6%), and percentage of boys aged 15-18 years being sexually active (44.4% versus 55.6%). Concerning the reliability of the third section of the questionnaire, Cronbach's alpha was deemed to be acceptable (α = 0.64). Statistically significant determinants of reporting lower scores in HPV-related attitudes and practices were religion (OR 1.44 [95%CI 1.02-2.04]), and male offspring (OR 1.22 [1.03-1.44]). This study has important implications for policy- and decision-makers in that they should be aware of the overall poor and unsatisfactory level of HPV-related knowledge among Israeli nurses and implement multipronged HPV vaccine promotion programs, taking into account the challenges of a multicultural and diverse society like Israel.

Immunotherapeutic approaches for HPV-caused cervical cancer

Cervical cancer, the fourth most frequent women cancer worldwide, is mostly (about 99%) associated with human papillomavirus (HPV). Despite availability of three effective prophylactic vaccines for more than one decade and some other preventive measures, it is still the fourth cause of cancer death among women globally. Thus, development of therapeutic vaccines seems essential, which has been vastly studied using different vaccine platforms. Even with very wide efforts during the past years, no therapeutic vaccine has been approved yet, which might be partly due to the complex events and interactions taken place in the tumor microenvironment. On the other hand, immunotherapy has opened its way into the management plans of some cancers. The recent approval of pembrolizumab for the treatment of metastatic/recurrent cervical cancer brings new hopes to the management of this disease, while some other immunotherapeutic approaches are also under investigation either alone or in combination with vaccines. Here, following a summary about HPV and its pathogenesis, cervical cancer therapeutic vaccines would be reviewed. Cell-based vaccines as well as immunomodulation and other modalities used along with vaccines would be also discussed.

The Role of Viruses in Carcinogenesis and Molecular Targeting: From Infection to Being a Component of the Tumor Microenvironment

About a tenth of all cancers are caused by viruses or associated with viral infection. Recent global events including the coronavirus disease-2019 (COVID-19) pandemic means that human encounter with viruses is increased. Cancer development in individuals with viral infection can take many years after infection, demonstrating that the involvement of viruses in cancer development is a long and complex process. This complexity emanates from individual genetic heterogeneity and the many steps involved in cancer development owing to viruses. The process of tumorigenesis is driven by the complex interaction between several viral factors and host factors leading to the creation of a tumor microenvironment (TME) that is ideal and promotes tumor formation. Viruses associated with human cancers ensure their survival and proliferation through activation of several cellular processes including inflammation, migration, and invasion, resistance to apoptosis and growth suppressors. In addition, most human oncoviruses evade immune detection and can activate signaling cascades including the PI3K-Akt-mTOR, Notch and Wnt pathways associated with enhanced proliferation and angiogenesis. This expert review examines and synthesizes the multiple biological factors related to oncoviruses, and the signaling cascades activated by these viruses contributing to viral oncogenesis. In particular, I examine and review the Epstein-Barr virus, human papillomaviruses, and Kaposi's sarcoma herpes virus in a context of cancer pathogenesis. I conclude with a future outlook on therapeutic targeting of the viruses and their associated oncogenic pathways within the TME. These anticancer strategies can be in the form of, but not limited to, antibodies and inhibitors.

High resolution cryo EM analysis of HPV16 identifies minor structural protein L2 and describes capsid flexibility

Human papillomavirus (HPV) is a significant health burden and leading cause of virus-induced cancers. HPV is epitheliotropic and its replication is tightly associated with terminal keratinocyte differentiation making production and purification of high titer virus preparations for research problematic, therefore alternative HPV production methods have been developed for virological and structural studies. In this study we use HPV16 quasivirus, composed of HPV16 L1/L2 capsid proteins with a packaged cottontail rabbit papillomavirus genome. We have achieved the first high resolution, 3.1 Å, structure of HPV16 by using a local subvolume refinement approach. The high resolution enabled us to build L1 unambiguously and identify L2 protein strands. The L2 density is incorporated adjacent to conserved L1 residues on the interior of the capsid. Further interpretation with our own software for Icosahedral Subvolume Extraction and Correlated Classification revealed flexibility, on the whole-particle level through diameter analysis and local movement with inter-capsomer analysis. Inter-capsomer expansion or contraction, governed by the connecting arms, showed no bias in the magnitude or direction of capsomer movement. We propose that papillomavirus capsids are dynamic and capsomers move as rigid bodies connected by flexible linkers. The resulting virus structure will provide a framework for continuing biochemical, genetic and biophysical research for papillomaviruses. Furthermore, our approach has allowed insight into the resolution barrier that has previously been a limitation in papillomavirus structural studies.

Antiviral therapy for the sexually transmitted viruses: recent updates on vaccine development

INTRODUCTION

The sexually transmitted infections (STIs) caused by viruses including human T cell leukemia virus type-1 (HTLV-1), human immunodeficiency virus-1 (HIV-1), human simplex virus-2 (HSV-2), hepatitis C virus (HCV), hepatitis B virus (HBV), and human papillomavirus (HPV) are major public health issues. These infections can cause cancer or result in long-term health problems. Due to high prevalence of STIs, a safe and effective vaccine is required to overcome these fatal viruses.

AREAS COVERED

This review includes a comprehensive overview of the literatures relevant to vaccine development against the sexually transmitted viruses (STVs) using PubMed and Sciencedirect electronic search engines. Herein, we discuss the efforts directed toward development of effective vaccines using different laboratory animal models including mice, guinea pig or non-human primates in preclinical trials, and human in clinical trials with different phases.

EXPERT OPINION

There is no effective FDA approved vaccine against the sexually transmitted viruses (STVs) except for HBV and HPV as prophylactic vaccines. Many attempts are underway to develop vaccines against these viruses. There are several approaches for improving prophylactic or therapeutic vaccines such as heterologous prime/boost immunization, delivery system, administration route, adjuvants, etc. In this line, further studies can be helpful for understanding the immunobiology of STVs in human. Moreover, development of more relevant animal models is a worthy goal to induce effective immune responses in humans.

Knowledge of Human Papillomavirus (HPV), Attitudes and Practices Towards Anti-HPV Vaccination Among Israeli Pediatricians, Gynecologists, and Internal Medicine Doctors: Development and Validation of an Ad Hoc Questionnaire

Human papillomavirus (HPV) is a highly widespread virus which is responsible for one of the most common sexually transmitted infections. Two main preventative strategies exist: anti-HPV vaccination and cervical screening. Health-care workers play a key role in promoting public health campaigns; however, vaccine hesitancy is an often under-recognized challenge. To investigate the overall knowledge of HPV and HPV-related issues, as well as the attitudes and practices of health professionals towards recommending the anti-HPV vaccine, an ad hoc knowledge, attitudes, and practices (KAP) questionnaire was developed and validated in a sample of 139 Israeli pediatricians, gynecologists, and internal medicine doctors. The KAP questionnaire was found to be psychometrically valid and sound (with an r_KR-20 coefficient of 0.74 for the second part and a Cronbach's alpha of 0.85 for the third part). Furthermore, the present study confirmed the importance of health-care providers in recommending the immunization practice. Parents that had been strongly advised by health-care providers to vaccinate their children accepted immunization for their girls (odds ratio (OR) 1.09 (95% CI 1.04-1.14)) and boys (OR 1.06 (95% CI 1.02-1.10)), had a lower probability of deciding to postpone the immunization appointment (OR 0.81 (95% CI 0.66-0.98)), had fewer doubts and concerns about the vaccine (OR 0.69 (95% CI 0.54-0.89)), and had a lower probability of refusing the vaccination (OR 0.93 (95% CI 0.86-0.99)). Interestingly, the use of new, emerging tools such as ad hoc websites, applications, and other interactive devices reduced vaccine hesitancy (OR 0.90 (95% CI 0.82-0.99)) and concerns about the side-effects of the vaccine (OR 0.92 (95% CI 0.86-0.99)). However, among Israeli health-care workers, knowledge was generally moderate, with updated information lacking in about 30% of surveyed health-care providers and approximately 20% of them not recommending the anti-HPV vaccine among boys. This study has practical implications for policy- and decision-makers in that they should be aware of the overall level of knowledge among health-care workers and should implement ad hoc educational interventions to address gaps in knowledge and help medical providers routinely recommend the anti-HPV vaccine both to male and female children and adolescents.

Advances in Designing and Developing Vaccines, Drugs and Therapeutic Approaches to Counter Human Papilloma Virus

Human papillomavirus (HPV) is a viral infection with skin-to-skin based transmission mode. HPV annually caused over 500,000 cancer cases including cervical, anogenital and oropharyngeal cancer among others. HPV vaccination has become a public-health concern, worldwide, to prevent the cases of HPV infections including precancerous lesions, cervical cancers, and genital warts especially in adolescent female and male population by launching national programs with international alliances. Currently, available prophylactic and therapeutic vaccines are expensive to be used in developing countries for vaccination programs. The recent progress in immunotherapy, biotechnology, recombinant DNA technology and molecular biology along with alternative and complementary medicinal systems have paved novel ways and valuable opportunities to design and develop effective prophylactic and therapeutic vaccines, drugs and treatment approach to counter HPV effectively. Exploration and more researches on such advances could result in the gradual reduction in the incidences of HPV cases across the world. The present review presents a current global scenario and futuristic prospects of the advanced prophylactic and therapeutic approaches against HPV along with recent patents coverage of the progress and advances in drugs, vaccines and therapeutic regimens to effectively combat HPV infections and its cancerous conditions.

Infection and coinfection by human papillomavirus, Epstein-Barr virus and Merkel cell polyomavirus in patients with squamous cell carcinoma of the larynx: a retrospective study

Background

Human papillomavirus (HPV) is recognized as an important risk factor for laryngeal carcinogenesis. Although HPV-16 and 18 have been strongly implicated, the presence of other high-risk HPV (HR-HPV) genotypes or the coinfection with Epstein-Barr virus (EBV) or Merkel cell polyomavirus (MCPV) may increase the risk, but their etiological association has not been definitively established.

Methods

We characterized the genotype-specific HPV and the frequency of EBV and MCPV infections through the detection of their DNA in 195 laryngeal specimens of squamous cell carcinoma (SCC) histologically confirmed.

Results

HPV DNA was detected in 93 (47.7%) specimens. HPV-11 was the most frequent with 68 cases (73.1%), and HPV-52 was the most frequently HR-HPV found with 51 cases, which corresponds to 54.8% of all HPV-positive specimens. EBV DNA was detected in 54 (27.7%) tumor tissue specimens of which 25 (46.3%) were in coinfection with HPV. MCPV DNA was detected only in 11 (5.6%) cases of which 5 (45.4%) were in coinfection with an HR-HPV. No association between the presence of DNA of the three examined viruses and the patient smoking habits, alcohol consumption, age, the keratinization status, differentiation grade, or localization of the tumor in the larynx were found.

Discussion

HPV-52 was the most prevalent HR-HPV, which may suggest that this and other genotypes in addition to HPV-16 and 18 could be considered for prophylaxis. However, further studies including non-cancer larynx cases and the evaluation of other molecular markers and viral co-infection mechanisms are needed to determine the role of the different HR-HPV genotypes, EBV, and MCPV in the etiology of SCC of the larynx.

Human papilloma virus: Apprehending the link with carcinogenesis and unveiling new research avenues (Review)

Human papilloma viruses (HPV) are a small group of non‑enveloped viruses belonging to the Papillomaviridae family with strong similarities to polyoma viruses. The viral particles consist of a genome in the form of a circular double‑stranded DNA, encompassing eight open reading frames, as well as a non‑enveloped icosahedral capsid. HPV infection is considered the most common sexually transmitted disease in both sexes and is strongly implicated in the pathogenesis of different types of cancer. 'High‑risk' mucosal HPV types, predominantly types 16, 18, 31, 33 and 35, are associated with most cervical, penile, vulvar, vaginal, anal, oropharyngeal cancers and pre‑cancers. Screening for HPV is necessary for the prognosis and for determining treatment strategies for cancer. Novel HPV markers, including proteomic and genomic markers, as well as anti‑papillomavirus vaccines are currently available. The aim of this comprehensive review was to thoroughly present the updated information on virus development, cancer occurrence, treatment and prevention strategies, in an attempt to shed further light into the field, including novel research avenues.

Viral Oncology: Molecular Biology and Pathogenesis

Oncoviruses are implicated in approximately 12% of all human cancers. A large number of the world's population harbors at least one of these oncoviruses, but only a small proportion of these individuals go on to develop cancer. The interplay between host and viral factors is a complex process that works together to create a microenvironment conducive to oncogenesis. In this review, the molecular biology and oncogenic pathways of established human oncoviruses will be discussed. Currently, there are seven recognized human oncoviruses, which include Epstein-Barr Virus (EBV), Human Papillomavirus (HPV), Hepatitis B and C viruses (HBV and HCV), Human T-cell lymphotropic virus-1 (HTLV-1), Human Herpesvirus-8 (HHV-8), and Merkel Cell Polyomavirus (MCPyV). Available and emerging therapies for these oncoviruses will be mentioned.

Modulation of DNA methylation by human papillomavirus E6 and E7 oncoproteins in cervical cancer

Human papillomaviruses (HPVs) are double stranded circular DNA viruses that infect cutaneous and mucosal epithelial cells. Almost 99% of cervical cancer has a HPV infection. The early oncoproteins E6 and E7 are important in this cellular transformation process. Epigenetic mechanisms have long been known to result in decisive alterations in DNA, leading to alterations in DNA-protein interactions, alterations in chromatin structure and compaction and significant alterations in gene expression. The enzymes responsible for these epigenetic modifications are DNA methyl transferases (DNMTs), histone acetylases and deacetylases. Epigenetics has an important role in cancer development by modifying the cellular micro environment. In this review, the authors discuss the role of HPV oncoproteins E6 and E7 in modulating the epigenetic mechanisms inside the host cell. The oncoproteins induce the expression of DNMTs which lead to aberrant DNA methylations and disruption of the normal epigenetic processes. The E7 oncoprotein may additionally directly bind and induce methyl transferase activity of the enzyme. These modulations lead to altered gene expression levels, particularly the genes involved in apoptosis, cell cycle and cell adhesion. In addition, the present review discusses how epigenetic mechanisms may be targeted for possible therapeutic interventions for HPV mediated cervical cancer.