A novel, broad spectrum therapeutic HPV vaccine targeting the E7 proteins of HPV16, 18, 31, 45 and 52 that elicits potent E7-specific CD8T cell immunity and regression of large, established, E7-expressing TC-1 tumors

Prevalence and Genotypic Diversity of Human Papillomavirus Infection Among Male and Female Sex Workers in Thailand

BACKGROUND

Human papillomavirus (HPV) is associated with cancer. Female sex workers (FSWs) are known to be at risk for HPV, but little is known about male sex workers (MSWs).

METHODS

We examined HPV prevalence and associated risk factors in both populations. During 2022, HPV testing using vaginal or penile samples, HIV testing, and interviews were performed among 100 MSWs and 100 FSWs in Chiang Mai, Thailand.

RESULTS

The prevalence of all HPV types was 63.5% (66% in MSW, 61% in FSW), HPV-16 prevalence was 14%, HPV-52 was 13%, and HPV-18 was 4%. There was no difference between MSW and FSW for these subtypes. The prevalence of HPV-16 or HPV-18 was 17%, and for HPV-16, HPV-18, or HPV-52, it was 26%. HIV-positive participants had a higher prevalence of all HPV types (94% vs. 60%, P = 0.004), HPV-16 or HPV-18 (39% vs. 15%, P = 0.018), and HPV-16, HPV-18, or HPV-52 (50% vs. 23%, P = 0.017).

CONCLUSIONS

We demonstrated an equally high HPV prevalence across the sexes. Further studies are needed to determine if this indicates an equal risk for cancer. Increased HPV awareness, screening, and vaccination should be considered, regardless of gender.

Harnessing tumor immunogenomics: Tumor neoantigens in ovarian cancer and beyond

Ovarian cancer is a major cause of death among gynecological cancers due to its highly aggressive nature. Immunotherapy has emerged as a promising avenue for ovarian cancer treatment, offering targeted approaches with reduced off-target effects. With the advent of next-generation sequencing, it has become possible to identify genomic alterations that can serve as potential targets for immunotherapy. Furthermore, immunogenomics research has revealed the importance of genetic alterations in shaping the cancer immune responses. However, the heterogeneity of immunogenicity and the low tumor mutation burden pose challenges for neoantigen-based immunotherapies. Further research is needed to identify neoantigen-specific tumor-infiltrating lymphocytes (TIL) and establish guidelines for patient inclusion criteria in TIL-based therapy. The study of neoantigens and their implications in ovarian cancer immunotherapy holds great promise, and efforts focused on personalized treatment strategies, refined neoantigen selection, and optimized therapeutic combinations will contribute to improving patient outcomes in the future.

Mathematical Modeling and Computational Prediction of High-Risk Types of Human Papillomaviruses

Cervical cancer is one of the main causes of cancer death all over the world. Most diseases such as cervical epithelial atypical hyperplasia and invasive cervical cancer are closely related to the continuous infection of high-risk types of human papillomavirus. Therefore, the high-risk types of human papillomavirus are the key to the prevention and treatment of cervical cancer. With the accumulation of high-throughput and clinical data, the use of systematic and quantitative methods for mathematical modeling and computational prediction has become more and more important. This paper summarizes the mathematical models and prediction methods of the risk types of human papillomavirus, especially around the key steps such as feature extraction, feature selection, and prediction algorithms. We summarized and discussed the advantages and disadvantages of existing algorithms, which provides a theoretical basis for follow-up research.

TLR9 in the Human Papilloma Virus Infections: Friend or Foe?

Immune system plays dual roles during human papilloma virus (HPV) infections, from defense against the virus to induction or stimulation of the HPV-related cancers. It appears that various differences within the immune-related genes and the functions of the immunological parameters of the patients are the main factors responsible for the roles played by immune system during HPV infections. Toll-like receptors (TLRs) play key roles in the recognition of viruses and activation of immune responses. The molecules also can alter the target cell intracellular signaling and may participate in the transformation of the infected cells. TLR9 is the unique intracellular member of TLRs that recognize foreign DNA, including viral DNA. Thus, TLR9 may play significant roles in the defense against HPV and its related cancers. This review article discusses TLR9 antiviral and pathological roles during HPV infection.

Construction and immune effect of an HPV16/18/58 trivalent therapeutic adenovirus vector vaccine

Objective

This study aims to prepare candidate vaccines for cervical cancer immunotherapy by inserting the fused genes of human papillomavirus (HPV)16/18/58 mE6E7 lacking transforming activity into an adenovirus vector and to verify its efficiency in model mice with tumor expressing the associated HPV genes.

Methods

The E6/E7 genes of HPV16/18/58 were point-mutated to abolish their transforming activity, and adenovirus (AD)-HPV16/18/58 mE6E7 adenovirus vaccine was constructed. The immune effect of the adenovirus vaccine against HPV16/18/58-type tumors was analyzed by tumor morphology, enzyme linked immunosorbent assay, enzyme-linked immunospot and specific cytotoxic T lymphocyte (CTL) and T lymphocyte subsets.

Results

The HPV16/18/58 mE6E7 plasmid containing point mutations was verified by quantitative real-time polymerase chain reaction (qRT-PCR), enzyme digestion and electrophoresis, and gene sequencing. qRT-PCR and Western blots verified that AD-HPV16/18/58 mE6E7 could express the HPV16 mE6E7, HPV18 mE6E7 and HPV58 mE6E7 fusion genes and proteins in cells. The results of animal experiments were as follows: In the vaccine group, the tumors formed later, the incubation period was longer, the growth was slower, growth was inhibited, and the survival period was significantly prolonged. The immunological results all showed that the vaccine could induce effective humoral and cellular immunity in mice with three types of tumors, compared with the phosphate buffered saline (PBS) group and the adenovirus-negative control (AD-NC) group, the differences were statistically significant (P < 0.05).

Conclusion

We successfully constructed the HPV16/18/58 trivalent therapeutic adenovirus vaccine AD-HPV16/18/58 mE6E7. The AD-HPV16/18/58 mE6E7 adenovirus vaccine can protect immunized mice to a certain extent from TC-1, U14/LV-HPV18 E6E7 and U14/LV-HPV58 E6E7 cells, which contain HPV16, 18 and 58 E6 and/or E7 genes, respectively.

HPV-inactive cell populations arise from HPV16-transformed human keratinocytes after p53 knockout

HPV-inactive head and neck and cervical cancers contain HPV DNA but do not express HPV E6/E7. HPV-positive primary head and neck tumors usually express E6/E7, however they may produce HPV-inactive metastases. These observations led to our hypothesis that HPV-inactive cancers begin as HPV-active lesions, losing dependence on E6/E7 expression during progression. Because HPV-inactive cervical cancers often have mutated p53, we investigated whether p53 loss may play a role in the genesis of HPV-inactive cancers. p53 knockout (p53-KO) by CRISPR-Cas9 resulted in a 5-fold reduction of E7 mRNA in differentiation-resistant HPV16 immortalized human keratinocytes (HKc/DR). E7 expression was restored by 5-Aza-2 deoxycytidine in p53 KO lines, suggesting a role of DNA methylation in this process. In-situ hybridization showed that p53 KO lines consist of mixed populations of E6/E7-positive and negative cells. Hence, loss of p53 predisposes HPV16 transformed cells to losing dependence on the continuous expression of HPV oncogenes for proliferation.

Intranasal Therapeutic Peptide Vaccine Promotes Efficient Induction and Trafficking of Cytotoxic T Cell Response for the Clearance of HPV Vaginal Tumors

Human papillomavirus (HPV)-induced cancers continue to affect millions of women around the world, and the five year survival rate under the current standard of care for these cancers is less than 60% in some demographics. Therefore there is still an unmet need to develop an effective therapy that can be easily administered to treat established HPV cervical cancer lesions. We sought to investigate the potential of an intranasal HPV peptide therapeutic vaccine incorporating the combination of α-Galactosylceramide (α-GalCer) and CpG-ODN adjuvants (TVAC) against established HPV genital tumors in a syngeneic C57BL/6J mouse model. We obtained evidence to show that TVAC, delivered by the mucosal intranasal route, induced high frequencies of antigen-specific CD8 T cells concurrent with significant reduction in the immunosuppressive regulatory T cells and myeloid derived suppressor cells in the tumor microenvironment (TME), correlating with sustained elimination of established HPV genital tumors in over 85% of mice. Inclusion of both the adjuvants in the vaccine was necessary for significant increase of antigen-specific CD8 T cells to the tumor and antitumor efficacy because vaccination incorporating either adjuvant alone was inefficient. These results strongly support the utility of the TVAC administered by needle-free intranasal route as a safe and effective strategy for the treatment of established genital HPV tumors.

A multi-genotype therapeutic human papillomavirus vaccine elicits potent T cell responses to conserved regions of early proteins

Despite an efficacious prophylactic human papillomavirus (HPV) vaccine there is still a considerable global burden of HPV-related disease. Therapeutic vaccines that could prevent cancers in at-risk women are urgently needed. Most candidate therapeutic vaccines have focused on two high-risk (hr) HPV genotypes, 16 and 18, and two viral targets, E6 and E7, which may limit global coverage and efficacy. We designed the synthetic gene '5GHPV3' by selecting conserved regions from each of the six early proteins and generating consensus sequences to represent five hrHPV genotypes. 5GHPV3 was delivered by plasmid DNA, chimpanzee adenovirus (ChAdOx1) and modified vaccinia Ankara (MVA) vectors in prime-boost regimens to mice. ChAdOx1-5GHPV3 / MVA-5GHPV3 induced higher magnitude and more durable HPV-specific T cell responses than other regimens. Vaccine-induced T cells were polyfunctional and persisted at high frequencies for at least six weeks. Importantly, HPV-specific effector CD8 + T cells were detected in the cervix following systemic administration of ChAdOx1-5GHPV3 / MVA-5GHPV3 and increased in frequency over time, indicating continued trafficking of T cells to the cervix. Finally, T cells specific for 5GHPV3 encoded antigens were detected by IFN-γ Elispot in women with current or past hrHPV infections, confirming the presence of epitopes relevant to natural immune control.

Therapeutic vaccines for high-risk HPV-associated diseases

Cancer is the second leading cause of death worldwide, and it is estimated that Human papillomavirus (HPV) related cancers account for 5% of all human cancers. Current HPV vaccines are extremely effective at preventing infection and neoplastic disease; however, they are prophylactic and do not clear established infections. Therapeutic vaccines which trigger cell-mediated immune responses for the treatment of established infections and malignancies are therefore required. The E6 and E7 early genes are ideal targets for vaccine therapy due to their role in disruption of the cell cycle and their constitutive expression in premalignant and malignant tissues. Several strategies have been investigated for the development of therapeutic vaccines, including live-vector, nucleic acid, peptide, protein-based and cell-based vaccines as well as combinatorial approaches, with several vaccine candidates progressing to clinical trials. With the current understanding of the HPV life cycle, molecular mechanisms of infection, carcinogenesis, tumour biology, the tumour microenvironment and immune response mechanisms, an approved HPV therapeutic vaccine seems to be a goal not far from being achieved. In this article, the status of therapeutic HPV vaccines in clinical trials are reviewed, and the potential for plant-based vaccine production platforms described.

Preclinical development of peptide vaccination combined with oncolytic MG1-E6E7 for HPV-associated cancer

Human papilloma virus (HPV)-associated cancer is a significant global health burden and despite the presence of viral transforming antigens within neoplastic cells, therapeutic vaccinations are ineffective for advanced disease. HPV positive TC1 cells are susceptible to viral oncolysis by MG1-E6E7, a custom designed oncolytic Maraba virus. Epitope mapping of mice vaccinated with MG1-E6E7 enabled the rational design of synthetic long peptide (SLP) vaccines against HPV16 and HPV18 antigens. SLPs were able to induce specific CD8+ immune responses and the magnitude of these responses significantly increased when boosted by MG1-E6E7. Logically designed vaccination induced multi-functional CD8+ T cells and provided complete sterilising immunity of mice challenged with TC1 cells. In mice bearing large HPV-positive tumours, SLP vaccination combined with MG1-E6E7 was able to clear tumours in 60% of mice and these mice were completely protected against a long term aggressive re-challenge with the TC1 tumour model. Combining conventional SLPs with the multi-functional oncolytic MG1-E6E7 represents a promising approach against advanced HPV positive neoplasia.

A novel therapeutic vaccine composed of a rearranged human papillomavirus type 16 E6/E7 fusion protein and Fms-like tyrosine kinase-3 ligand induces CD8+ T cell responses and antitumor effect

The development of cervical cancer is mainly caused by infection with high risk genotypes of human papillomavirus, particularly type 16 (HPV16), which accounts for more than 50% of cervical cancer. The two early viral oncogenes, E6 and E7, are continuously expressed in cervical cancer cells and are necessary to maintain the malignant cellular phenotype, thus providing ideal targets for immunotherapy of cervical cancer. In this study, a novel vaccine strategy was developed based on a rationally shuffled HPV16 E6/E7 fusion protein, the addition of Fms-like tyrosine kinase-3 ligand (Flt3L) or the N domain of calreticulin (NCRT), and the usage of a CpG adjuvant. Four recombinant proteins were constructed: m16E6E7 (mutant E6/E7 fusion protein), rm16E6E7 (rearranged mutant HPV16 E6/E7 fusion protein), Flt3L-RM16 (Flt3L fused to rm16E6E7), and NCRT-RM16 (NCRT fused to rm16E6E7). Our results suggest that Flt3L-RM16 was the most potent of these proteins in terms of inducing E6- and E7-specific CD8⁺ T cell responses. Additionally, Flt3L-RM16 significantly induced regression of established E6/E7-expressing TC-1 tumors. Higher doses of Flt3L-RM16 trended toward higher levels of antitumor activity, but these differences did not reach statistical significance. In summary, this study found that Flt3L-RM16 fusion protein is a promising therapeutic vaccine for immunotherapy of HPV16-associated cervical cancer.

Targeting the undruggable: immunotherapy meets personalized oncology in the genomic era

Owing to recent advances in genomic technologies, personalized oncology is poised to fundamentally alter cancer therapy. In this paradigm, the mutational and transcriptional profiles of tumors are assessed, and personalized treatments are designed based on the specific molecular abnormalities relevant to each patient's cancer. To date, such approaches have yielded impressive clinical responses in some patients. However, a major limitation of this strategy has also been revealed: the vast majority of tumor mutations are not targetable by current pharmacological approaches. Immunotherapy offers a promising alternative to exploit tumor mutations as targets for clinical intervention. Mutated proteins can give rise to novel antigens (called neoantigens) that are recognized with high specificity by patient T cells. Indeed, neoantigen-specific T cells have been shown to underlie clinical responses to many standard treatments and immunotherapeutic interventions. Moreover, studies in mouse models targeting neoantigens, and early results from clinical trials, have established proof of concept for personalized immunotherapies targeting next-generation sequencing identified neoantigens. Here, we review basic immunological principles related to T-cell recognition of neoantigens, and we examine recent studies that use genomic data to design personalized immunotherapies. We discuss the opportunities and challenges that lie ahead on the road to improving patient outcomes by incorporating immunotherapy into the paradigm of personalized oncology.

The potential of plants for the production and delivery of human papillomavirus vaccines

The available vaccines against human papillomavirus have some limitations such as low coverage due to their high cost, reduced immune coverage and the lack of therapeutic effects. Recombinant vaccines produced in plants (genetically engineered using stable or transient expression systems) offer the possibility to obtain low cost, efficacious and easy to administer vaccines. The status on the development of plant-based vaccines against human papillomavirus is analyzed and placed in perspective in this review. Some candidates have been characterized at a preclinical level with interesting outcomes. However, there is a need to perform the immunological characterization of several vaccine prototypes, especially through the oral administration route, as well as develop new candidates based on new chimeric designs intended to provide broader immunoprotection and therapeutic activity.

Polymeric nanoparticles for co-delivery of synthetic long peptide antigen and poly IC as therapeutic cancer vaccine formulation

The aim of the current study was to develop a cancer vaccine formulation for treatment of human papillomavirus (HPV)-induced malignancies. Synthetic long peptides (SLPs) derived from HPV16 E6 and E7 oncoproteins have been used for therapeutic vaccination in clinical trials with promising results. In preclinical and clinical studies adjuvants based on mineral oils (such as incomplete Freund's adjuvant (IFA) and Montanide) are used to create a sustained release depot at the injection site. While the depot effect of mineral oils is important for induction of robust immune responses, their administration is accompanied with severe adverse and long lasting side effects. In order to develop an alternative for IFA family of adjuvants, polymeric nanoparticles (NPs) based on hydrophilic polyester (poly(d,l lactic-co-hydroxymethyl glycolic acid) (pLHMGA)) were prepared. These NPs were loaded with a synthetic long peptide (SLP) derived from HPV16 E7 oncoprotein and a toll like receptor 3 (TLR3) ligand (poly IC) by double emulsion solvent evaporation technique. The therapeutic efficacy of the nanoparticulate formulations was compared to that of HPV SLP+poly IC formulated in IFA. Encapsulation of HPV SLP antigen in NPs substantially enhanced the population of HPV-specific CD8+ T cells when combined with poly IC either co-encapsulated with the antigen or in its soluble form. The therapeutic efficacy of NPs containing poly IC in tumor eradication was equivalent to that of the IFA formulation. Importantly, administration of pLHMGA nanoparticles was not associated with adverse effects and therefore these biodegradable nanoparticles are excellent substitutes for IFA in cancer vaccines.

Vaccine adjuvant uses of poly-IC and derivatives

Pathogen-associated molecular patterns (PAMPs) are stand-alone immunomodulators or 'danger signals,' that are increasingly recognized as critical components of many modern vaccines. Polyinosinic-polycytidylic acid (poly-IC) is a synthetic dsRNA that can activate multiple elements of the host defense in a pattern that parallels that of a viral infection. When properly combined with an antigen, it can be utilized as a PAMP-adjuvant, resulting in modulation and optimization of the antigen-specific immune response. We briefly review the preclinical and clinical uses of poly-IC and two poly-IC derivatives, poly-IC12U (Ampligen) and poly-ICLC (Hiltonol), as vaccine adjuvants.

Therapeutic in situ autovaccination against solid cancers with intratumoral poly-ICLC: case report, hypothesis, and clinical trial

Pathogen-associated molecular patterns (PAMP) are stand-alone innate and adaptive immunomodulators and critical vaccine components. We present a strategy of sequential intratumoral (i.t.) and intramuscular (i.m.) injections of the stabilized dsRNA viral mimic and PAMP, polyinosinic-polycytidylic acid-polylysine-carboxymethylcellulose (poly-ICLC, Hiltonol; Oncovir). We report the first treated patient, a young man with an exceptionally advanced facial embryonal rhabdomyosarcoma with extension to the brain. After treatment, the patient showed tumor inflammation consistent with immunotherapy, followed by gradual, marked tumor regression, with extended survival. Sequential i.t. and i.m. poly-ICLC injections mimicking a viral infection can induce an effective, in situ, personalized systemic therapeutic "autovaccination" against tumor antigens of a patient. We postulate a three-step immunomodulatory process: (i) innate-immune local tumor killing induced by i.t. poly-ICLC; (ii) activation of dendritic cells with Th1 cell- and CTL-weighted priming against the released tumor antigens; and (iii) i.m. poly-ICLC maintenance of the systemic antitumor immune response via chemokine induction, facilitation of CTL killing through the induction of costimulators such as OX40, inflammasome activation, and increase in the T-effector/Treg ratio. These results support the use of certain simple and inexpensive i.t. PAMPs to favorably stimulate effective immunity against solid cancers. A phase II clinical trial testing the hypothesis presented has begun accrual (clinicaltrials.gov, NCT01984892).

Tumor prevention in HPV8 transgenic mice by HPV8-E6 DNA vaccination

The genus beta human papillomavirus 8 (HPV8) is involved in the development of cutaneous squamous cell carcinomas (SCCs) in individuals with epidermodysplasia verruciformis. Immunosuppressed transplant recipients are prone to harbor particularly high betapapillomavirus DNA loads, which may contribute to their highly increased risk of SCC. Tumor induction in HPV8 transgenic mice correlates with increased expression of viral oncogenes E6 and E2. In an attempt to prevent skin tumor development, we evaluated an HPV8-E6-DNA vaccine, which was able to stimulate a detectable HPV8-E6-specific cell-mediated immune response in 8/15 immunized mice. When skin of HPV8 transgenic mice was grafted onto non-transgenic littermates, the grafted HPV8 transgenic tissue was not rejected and papillomas started to grow within 14 days all over the transplant of 9/9 non-vaccinated and 7/15 not successfully vaccinated mice. In contrast, no papillomas developed in 6/8 successfully vaccinated mice. In the other two of these eight mice, a large ulcerative lesion developed within the initial papilloma growth or papilloma development was highly delayed. As the vaccine completely or partially prevented papilloma development without rejecting the transplanted HPV8 positive skin, the immune system appears to attack only keratinocytes with increased levels of E6 protein, which would give rise to papillomas.

Intranasal immunization with recombinant Lactococci carrying human papillomavirus E7 protein and mouse interleukin-12 DNA induces E7-specific antitumor effects in C57BL/6 mice

The use of Lactococcus lactis for the co-delivery of antigens and cytokines has been shown to successfully induce a special immune response. However, it is unknown whether the same results may be triggered through immunization of animals with L. lactis simultaneously carrying protein antigen and cytokine DNA. The present study evaluated the protective effects of intranasally administered live L. lactis strains carrying human papillomavirus 16 E7 protein and murine interleukin-12 (IL-12) DNA (LL-E7_P-IL-12_D) in a TC-1 tumor animal model. C57BL/6 mice were intranasally immunized with recombinant lactococci, and assays for cytotoxicity measurement and tumor protection were carried out to assess the immunological effects of the vaccine candidates. IL-12 and interferon-γ serum levels were measured and immunization with LL-E7_P-IL-12_D was shown to induce an E7-specific immune response and to confer protection against TC-1-induced tumors in vivo. Mice in the LL-E7P-IL-12D group showed an 80% survival rate when the control mice had died. Therapeutic immunization with recombinant L. lactis strains 7 days after TC-1 injection led to a reduction in the number of palpable tumors in treated mice. The antitumor effects of the vaccination occurred through an E7-specific cytotoxic T-lymphocyte response. In the present study, the use of a single L. lactis strain, to co-administer protein antigen and adjuvant DNA, successfully induced an antigen-specific immune response. These observations demonstrate a new strategy for the use of L. lactis as a delivery vector of therapeutic molecules and antigens.

Genetic alterations in head and neck squamous cell carcinoma: The next-gen sequencing era

Head and neck squamous cell carcinoma is the sixth most common cancer in the world with approximately 650000 new cases diagnosed annually. Next-generation molecular techniques and results from phase 2 of the Cancer Genome Atlas becoming available have drastically improved our current knowledge on the genetics basis of head and neck squamous cell carcinoma. New insights and new perspectives on the mutational landscape implicated in head and neck squamous cell carcinoma provide improved tools for prognostication. More importantly, depend on the patient’s tumor subtypes and prognosis, deescalated or more aggressive therapy maybe chosen to achieve greater potency while minimizing the toxicity of therapy. This paper aims to review our current knowledge on the genetic mutations and altered molecular pathways in head and neck squamous cell carcinoma. Some of the most common mutations in head and neck squamous cell carcinoma reported by the cancer genome atlas including TP53, NOTCH1, Rb, CDKN2A, Ras, PIK3CA and EGFR are described here. Additionally, the emerging role of epigenetics and the role of human papilloma virus in head and neck squamous cell carcinoma are also discussed in this review. The molecular pathways, clinical applications, actionable molecular targets and potential therapeutic strategies are highlighted and discussed in details.

An enhanced heterologous virus-like particle for human papillomavirus type 16 tumour immunotherapy

Cervical cancer is caused by high-risk, cancer-causing human papillomaviruses (HPV) and is the second highest cause of cancer deaths in women globally. The majority of cervical cancers express well-characterized HPV oncogenes, which are potential targets for immunotherapeutic vaccination. Here we develop a rabbit haemorrhagic disease virus (RHDV) virus-like particle (VLP)-based vaccine designed for immunotherapy against HPV16 positive tumours. An RHDV-VLP, modified to contain the universal helper T cell epitope PADRE and decorated with an MHC I-restricted peptide (aa 48–57) from the HPV16 E6, was tested for its immunotherapeutic efficacy against the TC-1 HPV16 E6 and E7-expressing tumour in mice. The E6-RHDV-VLP-PADRE was administered therapeutically for the treatment of a pre-existing TC-1 tumour and was delivered with antibodies either to deplete regulatory T cells (anti-CD25) or to block T cell suppression mediated through CTLA-4. As a result, the tumour burden was reduced by around 50% and the median survival time of mice to the humane endpoint was almost doubled the compared to controls. The incorporation of PADRE into the RHDV-VLP was necessary for an E6-specific enhancement of the anti-tumour response and the co-administration of the immune modifying antibodies contributed to the overall efficacy of the immunotherapy. The E6-RHDV-VLP-PADRE shows immunotherapeutic efficacy, prolonging survival for HPV tumour-bearing mice. This was enhanced by the systemic administration of immune-modifying antibodies that are commercially available for use in humans. There is potential to further modify these particles for even greater efficacy in the path to development of an immunotherapeutic treatment for HPV precancerous and cancer stages.

New treatments for human papillomavirus infection

Human papillomavirus infection is very common. In this article, we review the latest developments in the treatment of lesions caused by this virus, with a particular focus on anogenital warts. Sinecatechins and new imiquimod formulations are among the most significant new developments. Others include photodynamic therapy and intralesional immunotherapy, but there is insufficient evidence to recommend their routine use. Finally, while therapeutic vaccines and inhibitory molecules appear to hold great promise, they are still in the early phases of investigation. More studies are needed, and these should have similar designs, larger samples, and sufficiently long follow-up periods to enable the direct comparison of the short-term and long-term effectiveness of different treatment options.

Role of infectious agents in the carcinogenesis of brain and head and neck cancers

This review concentrates on tumours that are anatomically localised in head and neck regions. Brain cancers and head and neck cancers together account for more than 873,000 cases annually worldwide, with an increasing incidence each year. With poor survival rates at late stages, brain and head and neck cancers represent serious conditions. Carcinogenesis is a multi-step process and the role of infectious agents in this progression has not been fully identified. A major problem with such research is that the role of many infectious agents may be underestimated due to the lack of or inconsistency in experimental data obtained globally. In the case of brain cancer, no infection has been accepted as directly oncogenic, although a number of viruses and parasites are associated with the malignancy. Our analysis of the literature showed the presence of human cytomegalovirus (HCMV) in distinct types of brain tumour, namely glioblastoma multiforme (GBM) and medulloblastoma. In particular, there are reports of viral protein in up to 100% of GBM specimens. Several epidemiological studies reported associations of brain cancer and toxoplasmosis seropositivity. In head and neck cancers, there is a distinct correlation between Epstein-Barr virus (EBV) and nasopharyngeal carcinoma (NPC). Considering that almost every undifferentiated NPC is EBV-positive, virus titer levels can be measured to screen high-risk populations. In addition there is an apparent association between human papilloma virus (HPV) and head and neck squamous cell carcinoma (HNSCC); specifically, 26% of HNSCCs are positive for HPV. HPV type 16 was the most common type detected in HNSCCs (90%) and its dominance is even greater than that reported in cervical carcinoma. Although there are many studies showing an association of infectious agents with cancer, with various levels of involvement and either a direct or indirect causative effect, there is a scarcity of articles covering the role of infection in carcinogenesis of brain and head and neck cancers. We review recent studies on the infectious origin of these cancers and present our current understanding of carcinogenic mechanisms, thereby providing possible novel approaches to cancer treatment.

Optimizing cancer treatments to induce an acute immune response: radiation Abscopal effects, PAMPs, and DAMPs

Clinical results indicate improved survival in poorly differentiated prostate cancer patients following a treatment schedule that maximizes hormone therapy prior to radiation. This may be because of a systemic immune response, called an abscopal effect. A literature review showed an association between acute infection and abscopal cancer remission. This led to the theory that, in the presence of endogenous cancer-specific antigens exposed by cancer necrosis, an innate immune response can adapt to respond to those antigens via a cross-talk mechanism. This theory was validated in an animal model. An acute innate immune T-cell response was stimulated using cluster vaccination with Poly(I:C). In the presence of exogenous cancer-specific antigens, this immune response became adaptive, creating an abscopal effect that resulted in cancer resolution. These concepts may be of clinical value, improving outcomes by inducing systemic abscopal effects.

New promising molecular targets in head and neck squamous cell carcinoma

PURPOSE OF REVIEW

Despite advances in multimodality therapy, the overall 5-year survival rate is 40-50% in patients with head and neck squamous cell carcinoma (HNSCC) and current multimodality approaches impart significant toxicities. This review highlights promising targets with the potential to improve clinical outcomes in HNSCC.

RECENT FINDINGS

In addition to mutagenic exposure to tobacco and alcohol as risk factors, recent studies have shown that human papillomavirus is one of the main causes of HNSCC and as such is being investigated as a therapeutic target. Furthermore, recent data generated from whole exome sequencing of HNSCC, new insights into the biology of DNA damage repair, and increased understanding of tumor hypoxia responses are pointing to new therapeutic possibilities for treating HNSCC.

SUMMARY

HNSCC is a heterogeneous disease. Improved treatment will require a rapid translation of basic science research, and the simultaneous development of novel therapeutics and corresponding biomarkers to guide their application.