Search Results (349)

Background: Therapeutic vaccination against human papillomavirus type 16 (HPV16) is frequently limited by the weak HLA-A*02:01 presentation of native E6/E7 oncoprotein epitopes. This study aims to utilize an integrated computational-experimental pipeline to design and evaluate anchor-optimized altered peptide ligands (APLs) for improving peptide presentation and HPV16-specific T-cell responses. Methods: Anchor-residue substitutions were introduced into three wild-type E6/E7 epitopes. Candidates were prioritized in silico based on predicted presentation, affinity, immunogenicity, and toxicity, and subsequently evaluated via in vitro functional assays using HLA-A*02:01-positive donor cells and molecular dynamics (MD) simulations. Results: Anchor optimization successfully converted weak binders into strong binders; for instance, E6apl improved predicted affinity from 329.33 to 6.21 nM. Crucially, candidate E7apl1 exhibited normal CD8⁺ T-cell expansion but reduced IFN-γ secretion, revealing a distinct binding–immunogenicity dissociation. MD simulations suggested that altered peptide conformational dynamics may contribute to differences in functional activity. Subsequently, an optimized six-peptide formulation (three APLs and three wild-type epitopes) was assembled. The resulting multi-epitope HPV-specific cytotoxic T lymphocytes (meHPV-CTLs) mediated target-specific cytotoxicity against cervical cancer cells, achieving 74.1% ± 5.1% specific lysis at an effector-to-target ratio of 30:1, which was largely abrogated by HLA class I blockade. Conclusions: These proof-of-concept findings demonstrate that stable peptide–MHC binding is a necessary but insufficient condition for optimal T-cell activation. The experimentally characterized multi-epitope formulation provides a proof-of-concept strategy for further preclinical evaluation of HPV16-targeted peptide-based immunotherapies. Moreover, because these anchor-optimized APLs are defined at the sequence level, these sequence-defined APLs may potentially be explored in alternative vaccine delivery platforms, including mRNA-based approaches, in future studies. Full article

Background/Objective: Persistent infection with human papillomavirus type 16 (HPV-16) is the principal cause of cervical high-grade squamous intraepithelial lesions (cHSIL) and cervical cancer, yet the established treatments remain limited to ablative or excisional procedures that carry reproductive risk and do not eliminate the underlying infection. We report the preclinical development of ARV-2001, a messenger RNA (mRNA)–lipid nanoparticle (LNP) immunotherapeutic encoding mutated, non-oncogenic HPV-16 E6 and E7 fused to a SARS-CoV-2 spike S2 subdomain enriched in human CD4 helper epitopes, formulated in a novel cholesterol-derived ionizable lipid (ARV-T1). Methods: Interactions of ARV-2001-expressed antigens with p53 and retinoblastoma (Rb) were evaluated in human cervical carcinoma cell line C33A, in lentiviral constructs in primary human keratinocytes, and in soft-agar colony-formation assays. ARV-2001 was administrated by intramuscular (IM) or intradermal (ID) injection in naive mice or in the TC-1 tumor models. Tumor size and survival were monitored over time and tumor-infiltrated lymphocytes were characterized by flow cytometry. Intracellular cytokine staining and Elispot were used to evaluate immunogenicity. Results: In vitro, the mutated E6/E7–S2 antigen lost the ability to degrade p53, to deregulate the retinoblastoma (Rb) pathway, and to support anchorage-independent growth, suggesting abrogation of oncogenic activity. The S2 domain and imiquimod administration each augmented antitumor activity and intratumoral CD8⁺ T-cell infiltration while reducing myeloid-derived suppressor cells in the syngeneic HPV-16 E6/E7 TC-1 tumor models. In addition, ID administration of ARV-2001 into TC-1 tumor-bearing mice was superior to IM administration in terms of both tumor growth inhibition and survival. ID vaccination with ARV-2001 in mice consistently elicited a more potent E6/E7-specific T-cell response than the same dose given IM. Dose-escalation studies showed a dose-dependent T cell response against E6/E7 in ID-injected mice. Conclusions: This study supports future human evaluation of intradermally administrated ARV-2001 for treatment of HPV-16+ cHSIL in clinical trials. Full article

Essential oils derived from plants have gained increasing interest in recent years for their potential antimicrobial, antiviral, and disinfectant properties. However, data specifically examining the virucidal efficacy of essential oils against human papillomavirus (HPV), a major human pathogen, remains very limited. In this study, we compared the chemical composition of sandalwood essential oils derived from five different species (Santalum album, S. austrocaledonicum, S. insulare, S. paniculatum, and S. spicatum). We further investigated the ability of S. album sandalwood oil, the species highest in α- and β-santalol content, to inactivate infectious HPV type 16 virions dried onto glass carriers at contact times of 5 and 30 min. HPV-16 is a high-risk HPV type frequently associated with cervical and other cancers. A RT-qPCR assay based on E1^E4 spliced transcript detection was used to measure viral infectivity levels post-treatment. S. album oil exhibited moderate but incomplete virucidal activity, achieving a mean 2.59 log reduction (99.7% inactivation) of HPV-16 after a 30 min contact time. In contrast, the shorter 5 min contact time resulted in negligible reductions in viral infectivity compared to untreated controls. These data suggest that while S. album oil has the ability to inactivate HPV, it requires relatively long contact times to achieve significant reduction. Full article

Human papillomavirus type 16 (HPV16) is a major etiological agent of cervical and other epithelial cancers, yet the mechanisms underlying host–pathogen interactions remain incompletely understood. In this study, we investigated the responses of human peripheral blood leukocytes to engineered HPV16 L1/L2 chimeric virus-like particles (VLPs), produced in suspension by HEK 293-F cells. These VLPs were designed to mimic native viral structures while incorporating chimeric features that enhance stability and immunogenicity. Through experimental assays, we characterized leukocyte engagement, primarily involving leukocyte phenotyping, VLP internalization, confocal colocalization, and endocytic pathway analyses. We demonstrated that recombinant L1/L2 proteins assembled into structured VLPs capable of interacting with mononuclear cells, including lymphocytes and monocytes, but not with polymorphonuclear cells, such as neutrophils, eosinophils and basophils. Uptake occurred via the CD71 transferrin receptor-mediated pathway, in addition to other endocytic routes analyzed, as confirmed by blockage assays using chlorpromazine, rCTB, filipin, nystatin, liquemine, and sodium azide. Confocal colocalization and endocytic pathway analyses further supported receptor-mediated uptake. These findings demonstrate that HPV16 L1/L2 chimeric VLPs interact with and are internalized by human peripheral blood mononuclear cells through CD71-associated and other endocytic pathways. The study provides new insights into HPV16 VLP–leukocyte interactions and contributes to a better understanding of the cellular mechanisms involved in VLP uptake, which may be relevant for future studies on HPV biology and VLP-based vaccine development. Full article

Background: Women treated for cervical intraepithelial neoplasia grade 2 (CIN2) face an increased risk of disease recurrence due to persistent or newly acquired human papillomavirus (HPV) infections, suggesting a potential role for adjuvant HPV vaccination. While a growing body of literature evaluates the outcomes of HPV vaccination following a large loop excision of the transformation zone (LLETZ) for high-grade squamous intraepithelial lesions (CIN2–3), data specifically focused on isolated CIN2 remain limited. This study aims to evaluate the clinical efficacy of the nonavalent HPV vaccine (9vHPV) as an adjuvant strategy to reduce CIN2+ recurrence in women undergoing LLETZ for histologically confirmed, isolated CIN2. Methods: Between November 2017 and November 2024, women undergoing LLETZ for histologically confirmed CIN2 received their first dose of adjuvant 9vHPV within one month of surgery. Patients who achieved double-negative co-testing (Pap test and high-risk HPV DNA test) at the 6-month post-LLETZ follow-up were included in the study group. Conversely, patients with at least one positive test result at 6 months were excluded to rule out residual disease. The study group underwent a subsequent Pap smear at 12 months and a full co-test at 18 months post-surgery; upon achieving negative results through the 18th month, patients returned to the organized screening program. The primary outcome was the recurrence rate, defined as histologically confirmed CIN2+ occurring more than 6 months post-treatment. It was compared against an unvaccinated historical control group treated with LLETZ prior to the study period. The secondary outcome evaluated the prevalence of HPV genotypes at baseline and at the time of recurrence. Results: In the vaccinated group, 3 women (2.03%) experienced CIN2+ recurrence compared to 6 women (5.71%) in the unvaccinated control group. This represents an absolute risk difference of 3.69% and a relative risk reduction of 64.6%, though the difference did not reach statistical significance via Fisher’s exact test (p = 0.165). In the study group, two recurrences were detected at 18 months (associated cytologies: ASC-H and LSIL; genotypes: HPV 51/53 and 16, respectively) and one at four years (cytology: HSIL; genotype: HPV 33/58). In the control group, recurrences occurred at 12 months (n = 3), 18 months (n = 2), and four years (n = 1). Associated cytology revealed HSIL in three cases, ASC-H in one case, LSIL in one case, and ASCUS in the final case. The corresponding HPV genotypes were 16 (two cases), 18, 51, 31 and 56 (co-infection), and one case of high-risk HPV, not further genotyped. Conclusions: Adjuvant 9vHPV administration after LLETZ for isolated CIN2 was associated with a clinically substantial lower absolute recurrence rate (2.03% vs. 5.71%, corresponding to a 64.6% relative risk reduction). Although this reduction did not achieve statistical significance ($p=0.165$) due to our small sample size and a low baseline recurrence rate in this isolated cohort, the effect size is highly comparable to broader CIN2+ studies. The study was likely underpowered to prove statistical significance, and larger multi-center studies are required to confirm the statistical value of adjuvant vaccination specifically in isolated CIN2 lesions. Full article

Cervical cancer (CC) affects women worldwide, and more than 95% of cases are caused by persistent infection with high-risk human papillomavirus (HR-HPV), such as type 16, which promotes the progression of precancerous lesions to cancer. This study aimed to identify differentially expressed proteins (DEPs) in biopsies from patients with HPV16+ low-grade squamous intraepithelial lesions (LSILs) and from patients with HPV16+ squamous cell carcinoma (SCC) compared with those from HPV-negative normal cervical tissue (NCT HPV−) controls. The samples were analyzed by high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS) using a data-independent acquisition (DIA) approach. Data processing and differential protein expression analysis were performed with the DIA-NN software (Data-Independent Acquisition Neural Networks), followed by bioinformatics analyses, including Venn diagrams, pathway enrichment, functional interactome, The Cancer Genome Atlas (TCGA)-SCC data integration, and Western blot detection. In total, 1607 DEPs associated with cell adhesion and extracellular matrix proteins were identified in LSILs, whereas 1516 DEPs associated with catalytic and transport activities were identified in SCC; the proteins overexpressed in LSILs (332) were enriched in processes such as metabolism, immune response activation, and stress and cell death responses. In contrast, proteins overexpressed in SCC (205) were associated with the cell cycle, DNA damage, drug metabolism, proteasome degradation, methylation, and immune response. Interaction analyses highlighted proteins related to early proteins 1,5,6 and 7 (E1, E5, E6, and E7). In terms of the two DEPs, S100 calcium binding protein A10 (S100A10/p11) and thymidine phosphorylase (TYMP) were detected in patients with LSIL, HSIL, and SCC at the protein level, consistent with their higher transcript levels in public datasets. Given the small, exploratory cohort, these findings are hypothesis-generating, and validation in a larger, balanced, independent cohort is required. In conclusion, this study identified DEPs associated with the progression of premalignant lesions to SCC that may represent candidate biomarkers and therapeutic targets warranting further investigation. Full article

Background/Objectives: Anal squamous cell carcinoma (SCCA) is an HPV-driven malignancy with rising incidence, yet systematic HPV genotyping across recurrences and metastases is lacking. We characterized the complete HPV genotype distribution across the disease course. Methods: We retrospectively analyzed 213 tumor specimens from 136 patients (82 female, 54 male) with histologically confirmed SCCA, spanning primary, recurrent, and metastatic disease (2009–2019 and from 2020 onwards). Patients contributed one or more specimens depending on the number of sampled disease events; specimens comprised 138 primary biopsies, 55 recurrence biopsies, 2 re-recurrence biopsies, and 18 distant metastases. HPV genotyping was conducted using a validated 28-type multiplex real-time PCR assay (Anyplex™ II HPV28, Seegene Inc.). Results: HPV DNA was detected in 179/213 specimens (84.0%; 95% CI 78.9–88.7) and 125/136 patients (91.9%; 95% CI 86.8–96.3). Across 269 HPV type detections, 24 distinct types were identified, with HPV 16 predominating both per-specimen (90.5%) and per-detection (60.2%) values. Non-HPV-16/18 high-risk types accounted for one in four high-risk detections (54/219; 24.7%; 95% CI 19.4–30.8). HPV positivity differed significantly by specimen type: 90.6% in primary biopsies versus 70.9% in recurrences (p = 0.001) and 72.2% in metastases (p = 0.038). Co-infections occurred in 24.6% of HPV-positive specimens (95% CI 18.5–31.6), with up to eight types. In metastases, the spectrum narrowed to 4 of 24 types; two harbored HPV 33 as the sole high-risk type. Conclusions: SCCA harbors a substantially broader HPV type spectrum than previously recognized. One in four high-risk detections lies beyond HPV 16/18, and high-risk types other than HPV 16 were the sole high-risk genotype detected in individual metastatic specimens. HPV positivity rates are significantly lower across specimen types, while the metastatic type spectrum converges on a few high-risk genotypes. Broad-spectrum HPV genotyping beyond types 16 and 18 warrants adoption as standard practice in SCCA diagnostics and surveillance, and potential stratification for HPV-directed therapies. Full article

Background: Head and neck squamous cell carcinomas (HNSCCs) are highly immunosuppressive, and tumor-associated macrophages constitute a major component of HNSCC tumor microenvironments. Here, we investigate the effects of circulating small extracellular vesicles (sEVs) from HNSCC patients on primary macrophages, to elucidate systemic sEV-mediated immune regulation in HNSCC patients. Methods: sEVs were isolated from plasma by size-exclusion chromatography. Internalization of PKH26-labeled sEVs was demonstrated, and mass spectrometry analysis was performed on HNSCC sEVs and sEV-treated macrophages. NF-κB activation was investigated by Western blot and p65 translocation assay. Downstream, mRNA and protein levels of cytokines and chemotaxis of T cells were investigated. Results: Proteomic analysis revealed time-dependent modulation of the macrophage proteome and NF-κB signaling pathway, which was confirmed by Western blot and p65 translocation assay. sEVs from HNSCC patients negative for human papillomavirus type 16 (HPV) differentially modulated NF-κB signaling and sEV uptake mechanisms compared with sEVs from HPV-positive patients and healthy donors. Conclusions: Circulating sEVs derived from HNSCC patient plasma modulate macrophage proteomic profiles and NF-κB signaling. HPV16 status was associated with differential sEV-mediated macrophage regulation, suggesting a potential role of sEVs in systemic immune modulation in HNSCC. Full article

Cancer incidence among adolescents is increasing, yet cancer risk reduction education remains largely absent from school-based curricula. This pilot study assessed whether a small-scale early, developmentally appropriate intervention could improve cancer literacy to support long-term risk reduction. This pilot study used a convergent parallel mixed-methods pre–post design to evaluate two separate, 45 min, school-based cancer education interventions delivered to 24 middle-school students in Pennsylvania. The intervention delivered developmentally appropriate content on cancer biology, modifiable risk factors, genetics, HPV vaccination, and self-advocacy using a low-resource, low-investment model easy for schools to implement. Pre- and post-intervention surveys assessed student knowledge, awareness, and health-related perceptions. Survey data were analyzed both descriptively using frequencies and percentages and thematically. Post-intervention results demonstrated substantial improvements across all domains. Correct definition of cancer increased from 16% to 100%. Awareness of modifiable risk factors increased to 96%, sunscreen knowledge to 90%, genetic testing awareness to 83%, and HPV vaccine understanding from 21% to 57%. Students also reported increased confidence in recognizing symptoms and engaging in health-seeking behaviors. Findings suggest that small-scale, school-based cancer education interventions are feasible and effective in improving adolescent cancer literacy. These results support the need for larger, controlled studies to evaluate long-term knowledge retention and behavioral outcomes. Full article

Pteridium aquilinum is a globally distributed plant species, highly adaptable to various environments and historically significant as a food source for both animals and humans. This study evaluated the in vivo effects of aqueous extracts from Pteridium aquilinum rhizomes and freeze-dried fiddleheads in a transgenic mouse model of human papillomavirus type 16 (HPV16)-induced cancer. Rhizome extract was administered in drinking water at concentrations of 0.0125, 0.025, and 0.05 g/mL for 28 days across six experimental groups (n = 5): G1 (wild-type, control), G2 (wild-type, 0.05 g/mL), G3 (HPV, control), G4 (HPV, 0.0125 g/mL), G5 (HPV, 0.025 g/mL), and G6 (HPV, 0.05 g/mL). Freeze-dried fiddleheads were incorporated into the diet at concentrations of 12.5%, 25%, and 50%, also using six groups (n = 5). Humane endpoints, body weight, and food and water consumption were monitored weekly. The rhizome extract was associated with more pronounced biological effects compared to fiddleheads, particularly at the histological and molecular levels. Conversely, freeze-dried fiddleheads were better tolerated. The results indicate that rhizomes were associated with great biological impact under the present experimental conditions, particularly in HPV16 transgenic mice, highlighting a potential synergistic effect with HPV. The potential risks associated with Pteridium aquilinum consumption, as well as preparation methods, should be carefully considered, even for rhizomes which are often regarded as less harmful than other plant parts. Full article

Background/Objectives: Human papillomavirus (HPV) infection is the leading cause of cervical cancer and is associated with several anogenital and oropharyngeal malignancies. Although licensed HPV vaccines are highly effective, access remains limited in many low- and middle-income countries due to cost, supply shortages, and implementation barriers. In this study, we evaluated the immunogenicity and safety of Gardisun, a newly developed quadrivalent prophylactic HPV vaccine, compared with Gardasil^®. Methods: This Phase III randomized, double-blind, active-controlled, parallel-group non-inferiority trial enrolled 450 healthy participants stratified by sex and randomized (1:1) to receive three 0.5 mL intramuscular doses of Gardisun or Gardasil^® on Days 0, 60, and 180. Participants were followed through to Day 210. The primary endpoint was the geometric mean titer (GMT) of antibodies against HPV types 6, 11, 16, and 18 one month after the administration of the third dose. Non-inferiority was defined as the lower bound of the 95% confidence interval (CI) for the GMT ratio exceeding 0.67. Safety was assessed through adverse event monitoring. Results: Of the 450 randomized participants, 422 completed the Month 7 visit and 429 received all three doses. Both vaccines induced antibody responses and seroconversion rates for all HPV types. The primary analysis met the non-inferiority criterion for HPV-6, while prespecified sensitivity analyses supported the existence of non-inferiority across all evaluated HPV types. Most adverse events were mild and transient, with no vaccine-related serious adverse events reported. Conclusions: Gardisun demonstrated robust immunogenicity and a safety profile comparable to that of Gardasil^®, supporting its potential as an accessible alternative quadrivalent HPV vaccine for broader vaccination programs in resource-limited settings. Full article

Background: The International Agency for Research on Cancer estimated around 3197 annual deaths along with 5008 newly diagnosed cases of cervical cancer in Pakistan. Worldwide, introduced in 164 WHO member states, the HPV vaccine provides over ninety percent (90%) protection from human papillomavirus (16 & 18 types) infections. This article intended to document the vaccine (HPV) introduction in a low-middle-income country through the lens of EPI preparedness, vaccination coverage achieved, community acceptance, and implementation challenges during Phase I. Methodology: The research applied a qualitative and quantitative mix method to review the intricate procedure of new vaccine rollout within the national context. A qualitative participant observation approach assessed the planning, approval, and implementation phases of the HPV vaccine. Quantitative data statistics were evaluated for national & regional vaccination coverages, rapid convenience assessment findings, and adverse events reports. Results: The overall reported administrative HPV campaign coverage was 75%, with the maximum regional coverage of 81% by the Punjab, followed by 66% of the Sindh, 43% by the Azad Jammu & Kashmir, and 38% by the Islamabad. Rapid Convenience Assessment findings highlighted the main reasons for refusal (71%), with unavailable girls during the campaign (22%) for non-HPV vaccination. Community acceptance varied across the regions, with notable challenges in implementation being observed. Discussion & Way Forward: Initial phase campaign coverage (70.6%) was greater than the worldwide reported first dose mean coverage (61.6%) for the same multi-age cohort, indicative of an encouraging start in resource limited setting. Documented coverage was below the high-performing countries but comparable to multiple low and middle-income countries. Federal Directorate of Immunization, in collaboration with provincial EPI stakeholders, should prioritize including the newly introduced HPV vaccine in the routine immunization schedule of the Phase I regions and should also implement the lessons learned in the subsequent rollout phases in 2026 in Khyber Pakhtunkhwa and 2027 in Balochistan & Gilgit Baltistan. Expanding fixed EPI sites for HPV vaccination, promoting school-centered vaccination, rationalizing outreach in marginalized areas, sustaining the cold chain system, implementing a culturally acceptable communication plan, and resolving internet connectivity challenges are the key strategies to address implementation challenges. Full article

Human papillomavirus (HPV) infection remains a major global health challenge, particularly when persistent high-risk genotypes lead to oncogenic progression. While prophylactic vaccines are effective, their role in accelerating the clearance of existing infections is still being explored. This study aimed to investigate the potential efficacy of adjunctive Pidotimod therapy combined with the nonavalent HPV vaccine in reducing persistent genotypes and promoting clearance in men. This retrospective pilot study included 23 HIV-negative men with anal and/or genital HPV infections. Participants were divided into two groups: 7 received the standard nonavalent HPV vaccine alone (control), and 16 received oral Pidotimod (800 mg twice daily for 10 days surrounding each vaccine dose) in addition to the vaccine (treatment). HPV genotyping (28 types) was performed at baseline and 12 months using real-time PCR. At 12 months, the HPV-negative conversion rate was 62.5% in the Pidotimod + vaccine group compared to 28.6% in the control group (p = 0.19). While this primary difference in total clearance was not statistically significant due to the limited sample size, the treatment group showed a substantial per-patient reduction in the number of persistent genotypes, decreasing from a mean of 2.75 ± 2.05 to 0.50 ± 0.82, compared to a decrease from 3.43 ± 2.37 to 1.86 ± 1.07 in the control group. The Pidotimod group achieved a significantly lower number of persistent genotypes at 12 months compared to the control group (p = 0.008, Mann–Whitney U test). Additionally, the use of pre-exposure prophylaxis (PrEP) was significantly associated with a lower rate of HPV clearance (12.5% vs. 73.3%, p < 0.01). Adjunctive therapy with Pidotimod suggests a promising trend in facilitating the reduction in HPV strain burden when combined with the HPV vaccine in men. While larger prospective studies are needed to confirm these effects, this exploratory approach could represent a promising immunomodulatory strategy for managing multiple and persistent HPV infections, even in high-risk groups such as PrEP users. Full article

Background: Cervical cancer is among the most common cancers affecting women worldwide, with high morbidity and mortality in low- and middle-income countries. In Saudi Arabia, most cases are diagnosed at a late stage despite the availability of free HPV vaccination and screening. Objectives: To identify Saudi women’s perceptions of the HPV vaccine using the Health Belief Model, estimate willingness to receive the HPV vaccine and the factors influencing it, assess uptake of Pap smear and HPV vaccine, and define barriers to both practices. Methodology: A cross-sectional study of a convenience sample of 1334 Saudi women aged 16 to 65 years, from all regions of Saudi Arabia, was conducted. Data were collected via an online questionnaire that included sociodemographic characteristics, beliefs about the HPV vaccine based on the Health Belief Model, vaccine hesitancy, and HPV vaccine and Pap smear uptake. Data were analyzed using SPSS version 29. Results: Only 6% completed their vaccination series or received at least one dose; 37.3% planned to get vaccinated; and 56.7% stated they do not intend to get vaccinated. The main reasons for vaccine refusal were lack of trust (41.8%) and fear of side effects (32.3%). Only 21% had undergone Pap smear testing, with barriers including embarrassment and fear. Among the HBM constructs, perceived susceptibility, benefits, and barriers remained statistically significant predictors of HPV vaccination. Increased perceived susceptibility and benefits raise the likelihood of accepting the HPV vaccine, while higher perceived barriers lessen it. Vaccine hesitancy had a significant negative effect on willingness to receive the HPV vaccine (OR = 0.78, 95% CI 0.69–0.90, p < 0.01). Additionally, Pap smear uptake was an independent predictor of the intent to get the HPV vaccine (OR = 1.78, 95% CI 1.25–2.54, p < 0.01). The independent factors influencing HPV vaccine uptake were largely similar to those affecting the willingness to receive the vaccine, except for age, perceived benefits, and Pap smear uptake. Conclusions: There is a gap between Saudi women’s intention to get HPV vaccinated and actual vaccination. Women who saw a high risk of HPV-related cancer, believed in vaccine efficacy, had a Pap smear, and were open to vaccination were more likely to vaccinate. Hesitant women and those perceiving barriers were less likely to vaccinate or consider it. The main gaps for future campaigns are perceptions of HPV severity and cultural factors influencing decision-making. Emphasizing HPV as a cancer-related virus rather than a sexually transmitted infection can reduce barriers and highlight its severity. Full article

Background: Persistent high-risk human papillomavirus (hrHPV) infection causes over 99% of cervical precancers and cancers worldwide, with HPV genotype 16 (HPV16) responsible for 50% of the cases. Latvia ranks among the top EU countries for cervical cancer incidence and mortality. In the general Latvian population, 4.2% of women are hrHPV-infected, mostly with HPV16. However, information on the circulating HPV16 isolates is missing. Objectives: To study the genomic variability of the Latvian HPV16 isolates, compare them with HPV16 in Europe and across the globe, reveal features associated with the severity of cervical disease and uncover eventual sequence changes due to the national HPV vaccination. Methods: DNA was extracted from the formalin-fixed paraffin-embedded cervical tissues of women diagnosed with cervical intraepithelial neoplasia (CIN) stages I-III and squamous cell carcinoma (SCC) grades 1–3, collected between 2012 and 2024. Samples positive for HPV16 were subjected to whole genome sequencing (WGS) on the Illumina platform (n = 16) or Sanger sequencing of the E6/E7 coding region (n = 31). A consensus HPV16 sequence was generated, and single nucleotide polymorphisms (SNPs) and eventual amino acid substitutions (AAS) were analysed. Results: Complete genomes of 16 HPV16 variants were reconstructed, with 13 related to the European sublineage A1 and 3 to the sublineage A2 references. Sequences showed high conservation; still 93 non-redundant variants were identified. The highest variability was observed for the capsid protein L2, and the lowest, for oncoprotein E7. The prevalence of SNPs and AAS in the Latvian HPV16 variants, specifically in capsid protein L1, did not increase with time, showing no effect of HPV vaccination. Associations between HPV16 sequence features and severity of cervical disease were limited to AAS E6:L90V, which was significantly more common in SCC grade 2/3 than in CINII/III cases (p = 0.015). Conclusions: Highly conserved HPV16 genomes circulating in Latvia harbour a series of unique as well as common nonsynonymous SNPs with respective AAS, with one, AAS E6:L90V, associating with disease severity. No HPV vaccine escape variants were detected. Deciphering complete genomes of HPV16 from CIN and SCC cases in Latvia informs public authorities performing HPV vaccination and is useful for the management of HPV-associated cervical diseases. Full article