Natural history of oral HPV infection: Longitudinal analyses in prospective cohorts from Australia

Longitudinal Screening for Oral High-Risk Non-HPV16 and Non-HPV18 Strains of Human Papillomavirus Reveals Increasing Prevalence among Adult and Pediatric Biorepository Samples: A Pilot Study

Most high-risk oral human papillomavirus research has focused on prevalent HPV16 and HPV18, with fewer studies focused on other high-risk strains incorporated into the nine-valent HPV vaccine. Therefore, the objective of this study was to determine the oral prevalence of non-HPV16 and non-HPV18 high-risk strains. A total of n = 251 existing biorepository saliva samples were screened using validated primers and qPCR. A total of n = 72 samples tested positive for HPV, including HPV31, HPV33, HPV35, HPV52, and HPV58. In addition, there were also significant increases in the prevalence of these high-risk strains (2011-2014, 21.3%) following the nine-valent HPV vaccine's introduction (2015-2019, 36.2%). However, the distribution of HPV-positive samples was nearly equal among males and females (52.8%, 47.2%, respectively, p = 0.5485), although the majority (66.7%) of the HPV-positive samples were within the HPV vaccination age (11 to 26 years) or catch-up range (27 to 45 years). These data demonstrated that the prevalence of high-risk oral HPV may be higher than anticipated, highly concentrated among patients within the recommended vaccination age range, and may be increasing over time-providing new evidence and support for the nine-valent HPV vaccine that covers these additional high-risk HPV strains.

Surveillance of human papillomavirus through salivary diagnostics - A roadmap to early detection of oropharyngeal cancer in men

Human papillomavirus (HPV) is the most common sexually transmitted disease. Certain strains have the potential to cause malignancy in multiple anatomical sites if not cleared by the immune system. In most infected people, HPV is cleared within two years. However, HPV may persist in susceptible individuals with certain risk factors, eventually leading to malignancy. New evidence suggests that over 75% of all oropharyngeal cancers (OPC) are directly attributable to HPV. It is estimated that prophylactic HPV vaccination alone may take at least 25 years to have a significant impact on reducing the incidence of OPC. The temporal link between detection of oral HPV, persistence of the infection and the subsequent development of OPC have been well established. Moreover, men have threefold higher risk than women for acquiring HPV-OPC. This comprehensive review focuses on OPC development in men, highlighting the risk factors associated with malignant transformation of HPV-OPC. Current evidence is insufficient to determine whether early identification of at-risk demographics, screening, and prompt diagnosis result in improved outcomes. Hitherto, the effectiveness of an oral HPV screening program in this regard has not been investigated. Nevertheless, the potential to emulate the success of the cervical screening program remains a very real possibility.

Oncogenic Oral Human Papillomavirus Clearance Patterns over 10 Years

BACKGROUND

Effective screening for oropharyngeal cancer is lacking. Four oncogenic HPV clearance definitions were explored to understand long-term natural history for persistent oncogenic oral HPV (oncHPV), the precursor of oropharyngeal cancer.

METHODS

Prospective multicenter cohort of participants living with/at-risk for HIV, with oral rinse and gargle samples collected every 6 to 12 months for up to 10 years and tested for oncHPV. HPV clearance definitions included 1 (clear1), 2 (clear2), 3 (clear3) consecutive negatives, or being negative at last two visits (clearlast).

RESULTS

Median time to clearance of oncHPV exceeded 2 years for conservative definitions (clear3: 2.38, clearlast: 2.43), but not lenient (clear1: 0.68, clear2: 1.15). By clear3, most incident infections cleared at 2, 5, 8 years (55.1%, 75.6%, 79.1%), contrary to prevalent infections (37.1%, 52.5%, 59.5%, respectively). In adjusted analysis, prevalent oncHPV, older age, male sex, and living with HIV were associated with reduced clearance. Of 1,833 subjects screened, 13.8% had prevalent oncHPV and 47.5% of those infections persisted ≥5 years, representing 6.5% of persons screened. Two men with prevalent oral HPV16 developed incident oropharyngeal cancer [IR = 1.62 per 100 person-years; 95% confidence interval (CI), 0.41-6.4]. Many with oral HPV16 persisted ≥5 years (and/or developed HPV-oropharyngeal cancer) among those with 2 (72.2%), ≥2 of first 3 (65.7%), or 3 (80.0%) consecutive positive oHPV16 tests, but not after 1 (39.4%).

CONCLUSIONS

In our 10-year study, most incident infections cleared quickly. However, half of prevalent oncHPV persisted ≥5 years, suggesting increased risk with persistent oncHPV at >2 visits.

IMPACT

We identified groups with persistent oncHPV at increased risk of oropharyngeal cancer and contextualized risk levels for those with oral HPV16 infection.

Investigating oral human papillomavirus co-infection with Neisseria gonorrhoeae and Chlamydia trachomatis

Compared to cervical cancer, little is known about human papillomavirus (HPV)-driven oropharyngeal cancer and their cofactors. Here, we investigated potential associations between Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) with oral HPV and HPV persistence, which are known cofactors in cervical carcinogenesis, and also play a role in HPV-driven oropharyngeal cancer. Saliva samples (n = 547) from 312 people were tested for CT and NG and whom had previously been tested for oral HPV infection in a longitudinal study. Eight participants were positive for CT (2.6%) and one for NG (0.3%). Six of these nine participants were also positive for oral HPV in at least one of their samples. We found no significant associations between HPV, CT, or NG infection in the saliva samples analyzed. These preliminary data suggest CT and NG have little influence on oral HPV-positivity and persistence in a general population. However, larger studies focusing on 'at risk' population cohorts are necessary to assess potential associations between oral sexually transmissible infections and oral HPV infections, and their outcomes.

Natural History of Oral HPV Infection among Indigenous South Australians

This study aims to describe the natural history of and identify the risk factors associated with oral human papillomavirus (HPV) infections in an Australian Indigenous cohort. A longitudinal cohort study design, with baseline (2018), 12-month, and 24-month data obtained from Indigenous Australians aged 18+ years in South Australia, was performed. Face-to-face interviews were conducted, and saliva samples for HPV testing were collected at each time point. Basic descriptive analyses were conducted to calculate prevalence, incidence, persistence, clearance, and incidence proportions of any HPV infection. Multivariable logistic regression analyses with adjusted prevalence ratios (PRs) were conducted to identify risk factors associated with oral HPV infection. Among 993 participants with valid saliva samples, 44 HPV types were identified. The prevalence of infection with any oral HPV infection was 51.3%, high-risk HPV was 11%, and types implicated in Heck's disease (HPV 13 or 32) was 37.4%. The incidence, persistence, and clearance of any and high-risk HPV infections were 30.7%, 11.8% and 33.3% vs. 9.3%, 2.8%, and 9%, respectively. Our findings indicate that the prevalence, incidence, and persistence of oral HPV infection in a large sample of Indigenous Australians were high, and clearance was low. Oral sex behaviours and recreational drug use were risk factors associated with incident high-risk HPV infection.

Self-reported HPV vaccination and vaccination record linkage in the Australian Oral Diversity Study

PURPOSE

Australia has a school-based human papillomavirus (HPV) vaccination scheme that was implemented for girls in 2007 and for boys in 2013. HPV vaccination status is important for many studies into HPV infection. Here we wanted to estimate the validity of self-reported HPV vaccination status by comparing self-report to data from the national vaccination register.

METHODS

Australian residents aged 18-70 years were recruited for the Oral Diversity Study from October 2020 to November 2021. Participants were asked to provide consent for record linkage to the Australian Immunisation Register (AIR). They were also asked to fill out a questionnaire about HPV vaccination, lifestyle, and sexual behavior.

RESULTS

1,023 participants were recruited, permission was received from 911 participants for HPV vaccination record linkage, and 850 self-reported vaccination and were part of the validity analysis. Of those 233 (26%) were confirmed to be HPV vaccinated. Ninety-one percent of the vaccinated were females (n = 212), 19 males and two non-binary. The highest HPV vaccine uptake was seen in the youngest age group (18-29 years; 80%), followed by 66% in 30-39 year olds, 2% in 40-49 year olds and then dropped significantly to 0.7% for people 50-70 years old. The sensitivity of self-report was 99.0%, and the specificity 94.5%, and the positive predictive value was 85.7% and the negative predictive value 99.7%.

CONCLUSION

We found that the correlation between self-reported Gardasil® vaccination and the AIR records were very good, with high sensitivity and specificity.

Dynamics of oral human papillomavirus infection in healthy population and head and neck cancer

The recent increase in high-risk human papillomavirus (HR-HPV)-associated oral and oropharyngeal cancers has gained considerable importance due to their distinct clinical and molecular characteristics. However, the natural history of oral HPV from acquisition to persistence and malignant transformation is still unclear. The global prevalence of oral HPV infection in healthy individuals ranges from 0.67% to 35%, while 31%-38.5% in head and neck cancer (HNC). The persistence rate of oral HR-HPV infection is 5.5% -12.8% globally. India has the highest HNC burden due to apparent differences in predisposing factors compared with the West. The prevalence of oral HPV in healthy individuals and its contribution to HNC is less evident in Indian studies. HR-HPV-associated HNC in this region accounts for 26%, with an active infection in 8%-15% of these tumors. There is a lack of concordance in the expression of p16 as a surrogate marker for HPV detection in HNC because of differences in behavioral risk factors. Due to a lack of evidence, treatment de-escalation cannot be implemented despite the improved outcome of HPV-associated oropharyngeal cancers. This review critically analyzes the existing literature on the dynamics of oral HPV infection and HPV-associated HNC, identifying potential avenues for future research. A better understanding of the oncogenic role of HR-HPV in HNC will help to formulate novel therapeutic approaches and is expected to have a significant public health impact as preventive strategies can be implemented.

Molecular characterization and risk factors of oral high-risk human papillomavirus among females in Punjab, Pakistan

BACKGROUND

The development of oral and oropharyngeal cancers is associated with human papillomavirus (HPV) infection. However, debate exists about the prevalence of high-risk oral HPV (HR-HPV) and its associated risk factors. This study evaluated the distribution of genotypes and associated risk factors of oral HR-HPV infection in the normal oral mucosa of the Pakistani female population with general gynecological problems.

METHODS

A total of 200 females from a regional gynecological hospital in Pakistan were included in this cross-sectional study. A self-administered questionnaire was carried out, followed by the study participants' oral and dental examinations. Whole saliva was collected by a drooling method. The viral DNA extraction and oral HR-HPV genotyping were detected via real-time polymerase chain reaction.

RESULTS

Among the 200 females (mean age, 37.76 years), 22 females (11%) were positive for oral HR-HPV DNA. Single oral HR-HPV infection was seen in 8%, whereas co-infection was observed in 3% with HPV16 and HPV18 most common genotypes. Comparison of the risk factors like oral sex history odds ratio (OR 8.21, 95% confidence interval [CI] 1.85-28.16; p < 0.005), and open-mouth kissing (OR, 5.17; 95% CI 1.48-27.41; p = 0.005) with oral HR-HPV infection was found to be significantly associated.

CONCLUSION

In Pakistan, oral HR-HPV-positive infection is not uncommon; HPV16 and HPV18 are the most frequent genotypes. Furthermore, this study also provides data that oral HR-HPV positive infection was significantly associated with sexual behaviors. Therefore, preventive health efforts, like health education and vaccination, should be practiced.

Antimicrobial peptides: Defending the mucosal epithelial barrier

The recent epidemic caused by aerosolized SARS-CoV-2 virus illustrates the importance and vulnerability of the mucosal epithelial barrier against infection. Antimicrobial proteins and peptides (AMPs) are key to the epithelial barrier, providing immunity against microbes. In primitive life forms, AMPs protect the integument and the gut against pathogenic microbes. AMPs have also evolved in humans and other mammals to enhance newer, complex innate and adaptive immunity to favor the persistence of commensals over pathogenic microbes. The canonical AMPs are helictical peptides that form lethal pores in microbial membranes. In higher life forms, this type of AMP is exemplified by the defensin family of AMPs. In epithelial tissues, defensins, and calprotectin (complex of S100A8 and S100A9) have evolved to work cooperatively. The mechanisms of action differ. Unlike defensins, calprotectin sequesters essential trace metals from microbes, which inhibits growth. This review focuses on defensins and calprotectin as AMPs that appear to work cooperatively to fortify the epithelial barrier against infection. The antimicrobial spectrum is broad with overlap between the two AMPs. In mice, experimental models highlight the contribution of both AMPs to candidiasis as a fungal infection and periodontitis resulting from bacterial dysbiosis. These AMPs appear to contribute to innate immunity in humans, protecting the commensal microflora and restricting the emergence of pathobionts and pathogens. A striking example in human innate immunity is that elevated serum calprotectin protects against neonatal sepsis. Calprotectin is also remarkable because of functional differences when localized in epithelial and neutrophil cytoplasm or released into the extracellular environment. In the cytoplasm, calprotectin appears to protect against invasive pathogens. Extracellularly, calprotectin can engage pathogen-recognition receptors to activate innate immune and proinflammatory mechanisms. In inflamed epithelial and other tissue spaces, calprotectin, DNA, and histones are released from degranulated neutrophils to form insoluble antimicrobial barriers termed neutrophil extracellular traps. Hence, calprotectin and other AMPs use several strategies to provide microbial control and stimulate innate immunity.

Sexual debut and association with oral human papillomavirus infection, persistence and oropharyngeal cancer-An analysis of two Australian cohorts

Oropharyngeal cancer is increasingly caused by human papillomavirus (HPV), and this increase is believed to be caused by changing sexual behaviour. It has been hypothesised that an immune response to HPV through sexual intercourse is much stronger than an immune response elicited from oral sex. Therefore, people who have their debut of oral sex before or at the same time as sexual intercourse would have a weaker immune response to HPV and hence be more likely to develop a persistent oral HPV infection and oropharyngeal cancer. Drake et al (Cancer. 2021;127[7]:1029-1038) found some evidence that supported this hypothesis. We have reanalysed two of our Australian cohorts with similar data in order to provide a perspective of Drake and colleagues' publication, as sexual behaviour varies depending on culture and geographical location. We found that engaging in oral sex (OR 4.46, 95% CI [1.88-10.62]) and being younger than 20 years at oral sex debut (OR 9.46, 95% CI [3.53-25.31]) were both very strong risk factors for oropharyngeal cancer. Participants in the general population cohort who had their sexual intercourse debut before the age of 18 were more likely to be oral HPV positive (OR 2.69, 95% CI [1.50-4.83]). Oral sex debut before sexual intercourse debut was quite uncommon in our two Australian cohorts. However, timing of or sexual debuts may further add to risks of oropharyngeal cancer, and future studies should be designed to investigate timing and order of sexual debuts to help clarify the roles of these potential causal factors.

Oral HPV infection among Indigenous Australians; incidence, persistence and clearance at 12-months follow-up

BACKGROUND

Persistent oral human papillomavirus (HPV) infection is a risk factor for oropharyngeal squamous cell carcinoma (OPSCC). Indigenous Australians have a higher rate of OPSCC than non-Indigenous Australians. Risk factors for oral HPV persistence among Indigenous Australians are poorly understood.

METHODS

Participants provided information on socio-demographic characteristics, health-related behaviours including tobacco and alcohol use and sexual history. Participants additionally provided saliva samples for microbial genotyping. Negative log binomial regression models were used to evaluate indicators on incident, persistent and cleared oral HPV infection at 12 months follow-up.

RESULTS

Of the 1,011 participants recruited at baseline, 321 (35.3%) testing positive for any oral HPV infection. At 12-month follow up, saliva samples were obtained from 743 participants (73.5%). Among the 584 participants, 24 (42.6%) had no oral HPV infection at both time points, 130 (22.2%) had new (incident) oral HPV infection at 12 months, 130 (22.2%) had persistent oral HPV infection (i.e. present at both baseline and 12-months), and 75 (12.8%) had oral HPV infection clearance from baseline to 12-months. Rural location of residence and ever received oral sex were significantly associated with persistence of oral HPV infection.

CONCLUSIONS

The incidence of oral HPV infection at both baseline and 12-month follow-up was high.

IMPACT

There are currently no studies available which have assessed oral HPV infection incidence, persistence and clearance amongst Indigenous populations in Australia or even at a global level. The study has been able to identify risk factors associated with potential malignant changes in the oropharynx among Indigenous Australians.

Human Papillomavirus Oral Infection: Review of Methodological Aspects and Epidemiology

Oral infection by Human Papillomavirus (HPV) has recently gained great attention because of its involvement in the development of a subset of head and neck squamous cell carcinoma. The role of specific Alpha-HPVs in this regard has been well established, whereas the contribution of other genera is under investigation. Despite their traditional classification as “cutaneous” types, Beta and Gamma HPVs are frequently detected in oral samples. Due to the lack of a standardized protocol, a large variety of methodologies have been used for oral sample collection, DNA extraction, HPV detection and genotyping. Laboratory procedures influence the evaluation of oral HPV prevalence, which largely varies also according to the population characteristics, e.g., age, gender, sexual behavior, Human Immunodeficiency Virus (HIV) status. Nevertheless, oral infection by Beta and Gamma HPVs seems to be even more common than Alpha-HPVs. The latter is 5–7% in the general population, and increases up to 30% approximately in HIV-infected men who have sex with men. Despite major advances in the evaluation of oral HPV prevalence, its natural history is still little understood, especially for Beta and Gamma HPVs. The latest technologies, such as Next Generation Sequencing (NGS), can be exploited to gain new insights into oral HPV, and to improve the identification of novel HPV types.

A micro-peptide encoded by HOXB-AS3 promotes the proliferation and viability of oral squamous cell carcinoma cell lines by directly binding with IGF2BP2 to stabilize c-Myc

HOXB-AS3 is a long non-coding RNA and recent studies have shown that the HOXB-AS3-encoded micro-peptide was associated with the progression of colon cancer tumorigenesis; however, the biofunction of HOXB-AS3 varies in different types of cancer and the potential function in oral squamous cell carcinoma (OSCC) is still unknown. The Cancer Genome Atlas (TCGA) database was searched and the expression patterns of HOXB-AS3 in head and neck carcinoma were analyzed. Reverse transcription-quantitative PCR and western blot analysis was used to measure the mRNA and protein expression level of HOXB-AS3 in patients with OSCC, respectively. Next, HOXB-AS3 was knocked down in 2 OSCC cell lines to investigate the biological function of the HOXB-AS3-encoded protein using a Cell Counting Kit-8 and colony formation assays. To further identify the potential mechanism of the HOXB-AS3-encoded protein, co-immunoprecipitation was also used to detect the interaction between HOXB-AS3 and IGF2BP2, while HOXB-AS3 was re-expressed to determine whether the HOXB-AS3-encoded protein and not HOXB-AS3 exerted its function in OSCC. HOXB-AS3 was upregulated in OSCC tissues, in both TCGA database and in patients with OSCC recruited into the present study. HOXB-AS3 was associated with poor prognosis in OSCC. The proliferation and viability decreased in the 2 OSCC cell lines following knock down of HOXB-AS3. HOXB-AS3 was also found to encode a protein that directly interacted with IGF2BP2 and thereby promoted the stability of c-myc. Taken together, the results from the present study indicated that increased HOXB-AS3 expression was associated with poor prognosis in OSCC. This indicated that HOXB-AS3 and its encoded protein promoted OSCC cell proliferation and viability by maintaining c-Myc mRNA stability by directly binding to IGF2BP2.

Cohort profile: indigenous human papillomavirus and oropharyngeal squamous cell carcinoma study - a prospective longitudinal cohort

PURPOSE

Our aims are to: (1) estimate prevalence, incidence, clearance and persistence of oral human papillomavirus (HPV) infection among Indigenous Australians; (2) identify risk factors associated with oropharyngeal squamous cell carcinoma (OPSCC)-related HPV types (HPV 16 or 18); (3) develop HPV-related health state valuations and; (4) determine the impact on OPSCC and cervical cancers, and the cost-effectiveness of extending publicly-funded HPV vaccination among Indigenous Australians.

PARTICIPANTS

Participants were recruited from February 2018 to January 2019. Twelve-month follow-up occurred from March 2019 to March 2020. Participants provided socio-demographic characteristics, health-related behaviours including tobacco and alcohol use and sexual history. Health state preferences in regard to HPV vaccination, knowledge regarding HPV infection, OPSCC and cervical cancer were collected using a two-stage standard gamble approach. Participants provided saliva samples and DNA for microbial genotyping was extracted.

FINDINGS TO DATE

Of the 910 participants who were positive for β-globin at baseline, 35% had any oral HPV infection. The most prevalent HPV types were 13 or 32 (Heck's disease; 23%). The second most prevalent types were associated with OPSCC (HPV 16 or 18; 3.3%). Of the 645 participants who were positive for β-globin at 12-month follow-up, 43% had any HPV infection. Of these, 33% were HPV types 13 or 32 and 2.5% were HPV 16 or 18. Some 588 participants had β-globin positive oral samples at baseline and 12-month follow-up. The prevalence of any oral HPV infection increased from 34% at baseline to 44% at 12-month follow-up; due to increases in HPV types 13 or 32 (20% at baseline and 34% at 12-month follow-up).

FUTURE PLANS

Further funding will be sought to continue follow-up of this cohort, and to include (after a full medical history) a thorough clinical examination of the external head and neck; a complete oral examination and examination of the oropharynx. Blood tests for early stage OPSCC will also be undertaken.