Investigation into a possible association between oral lichen planus, the human herpesviruses, and the human papillomaviruses

Update on human herpesvirus 7 pathogenesis and clinical aspects as a roadmap for future research

Human herpesvirus 7 (HHV-7) is a common virus that is associated with various human diseases including febrile syndromes, dermatological lesions, neurological defects, and transplant complications. Still, HHV-7 remains one of the least studied members of all human betaherpesviruses. In addition, HHV-7-related research is mostly confined to case reports, while in vitro or in vivo studies unraveling basic virology, transmission mechanisms, and viral pathogenesis are sparse. Here, we discuss HHV-7-related literature linking clinical syndromes to the viral life cycle, epidemiology, and viral immunopathogenesis. Based on our review, we propose a hypothetical model of HHV-7 pathogenesis inside its host. Furthermore, we identify important knowledge gaps and recommendations for future research to better understand HHV-7 diseases and improve therapeutic interventions.

HPV related p16INK4A and HSV in benign and potentially malignant oral mucosa pathologies

BACKGROUND

The association of Human Papilloma Virus (HPV) and Human Syncytial Virus (HSV) infection with inflammatory and potentially malignant disorders of the oral cavity (OPMD) is unknown. The aim of this cross-sectional study was to stablish the expression of the p16INK4A and HSV proteins, to test potential correlation between those parameters in biopsies from clinically diagnosed oral lesions.

METHODS

Immunochemical analysis of 211 formalin-fixed, paraffin-embedded (FFPE) blocks from 211 individuals was provided. The clinical diagnosis included in the research were Oral lichen planus (N = 30), Oral Leukoplakia (N = 13) Mucocele (N = 25), Erosion/ulceration/ inflammation of mucosa (N = 8), Overgrowth of mucosa (N = 135).

RESULTS

Two hundred eleven analyzed FFPE samples resulted with the median age of 58.5 years (the average age 54.0 years and SD ± 17 years). The female/male ratio was 2.3 (69.7% vs 30.3% respectively). All the samples positive for HSV also expressed p16INK4A (p = 0.000), that's showed various levels of association with the diverse clinical diagnosis reaching the higher level in OM 49.1% (29 positive samples) and OLP 30.5% (18). p16INK4A was associated with OLP at 30.5% (18), and fibroma 30.5%. HSV expression was mostly present in fibroma at 47.6% (10 positive samples).

CONCLUSION

HSV and p16INK4A positivity in relation to diagnosis of the biopsies showed statistically most often p16INK4A in OLP and fibroma. The results of co-expression of p16INK4A and HSV in mucocele and fibroma in oral mucosa suggest a cooperation between the molecular alterations induced by these two viruses. Squamous papilloma samples positive for p16INK4A were also positive for HSV, suggesting that the putative pro-oncogenic action of HSV could be an early event.

The correlation between human papillomavirus and oral lichen planus: A systematic review of the literature

INTRODUCTION

Oral lichen planus (OLP) is a chronic inflammatory disorder with cell-induced immunopathological responses and is considered a potential malignancy disorder in the oral cavity. Due to the high prevalence of OLP as well as the potential for malignancy, human papillomaviruses (HPVs) may play an important role in it. Although previous studies have explored the possible relationship between HPV and OLP, the findings have been conflicting and nonconclusive. This study aims to review the studies that investigated HPV-16 and HPV-18 in OLP.

METHODS AND MATERIALS

The research protocol followed the Preferred Reporting Items for Systematic Reviews (PRISMA2020) checklist. The online databases Pubmed, Scopus, Embase, Google Scholar, and Cochrane were searched using the following individual keywords: "OLP" OR "Oral Lichen Planus" OR "HPV" OR "Human Papillomavirus." The search strategy resulted in the selection of 80 articles. The articles were evaluated, and after duplication removal, 53 abstracts were reviewed, resulting in the selection of 25 studies according to inclusion and exclusion criteria. The risk of bias assessment was done by using the Modified Newcastle-Ottawa quality assessment scale. The overall prevalence of HPV in OLP lesions varied from 2.7% to 70%, depending on the type of diagnostic method used.

CONCLUSION

Despite the studies conducted on the relationship between OLP and HPV infection, there is still no conclusive evidence that HPV can play a role in the etiopathogenesis of OLP, either in clinical manifestations or in the malignant transformation of lesions.

Correlation between Oral Lichen Planus and Viral Infections Other Than HCV: A Systematic Review

OBJECTIVES

This review aimed to evaluate the correlation between viral infections (HPV, EBV, HSV-1, CMV) other than HCV and oral lichen planus to assess if there is sufficient evidence to establish if these viruses can play a role in the etiopathogenesis of the disease.

MATERIALS AND METHODS

We reviewed the literature using different search engines (PubMed, ISI Web of Science, and the Cochrane Library), employing MeSH terms such as "oral lichen planus" and "OLP" in conjunction with other terms. We utilized the Population, Intervention, Comparison, Outcomes, and Study design (PICOS) method to define our study eligibility criteria.

RESULTS

A total of 43 articles of the 1219 results initially screened were included in the study. We allocated the 43 selected items into four groups, according to each related virus: HPV, EBV, HSV-1, and CMV.

CONCLUSIONS

Heterogeneous results neither confirm nor exclude a direct correlation between the investigated viral infections and oral lichen planus etiopathogenesis and its feasible malignant transformation. Many viral agents can cause oral lesions and act as cancerizing agents. Future studies could be desirable to produce comparable statistical analyses and enhance the quantity and quality of the outcomes to promote the translation of research into clinical practice.

Oral Microbiome Research on Oral Lichen Planus: Current Findings and Perspectives

Simple Summary

Oral lichen planus is a disease of the oral mucosa, which frequently affects women aged 40 years or older. Though the T cell-mediated immune response is involved in the development of oral lichen planus, attempts to identify a microorganism that causes the disease have been unsuccessful. Recent studies on the development of oral lichen planus are focusing on the role of the oral microbiome, which includes oral microbiota and their products, and the host environment. The role of the human microbiome in various diseases has been identified and regulating the microbiome is becoming important in personalized medicine. In this review, we summarized current findings on the role of the oral microbiome in the development of oral lichen planus. The homeostasis of the oral microbiome is disrupted in patients, and functional analysis of oral microbiota and oral mucosa implies that pathways involved in defense against bacterial infection and in the inflammatory response are activated in the oral lichen planus-associated oral microbiome. Though the lack of studies to date makes it difficult to conclude, further studies on the oral microbiome associated with the disease will enable a holistic understanding of the role of the oral microbiome in the development of oral lichen planus and developing a personalized therapy for the disease.

Abstract

Oral lichen planus (OLP) is a chronic inflammatory disease of the oral mucosa with an unknown etiology. The role of oral microbes in the development of OLP has gained researchers’ interest. In this review, we summarized the findings of studies focused on the relationship between OLP and oral microbiome, which includes the composition of oral microbiota, molecules produced by oral microbiota or the host, and the oral environment of the host. According to the studies, the oral microbial community in OLP patients undergoes dysbiosis, and the microbial dysbiosis in OLP patients is more prominent in the buccal mucosa than in the saliva. However, no same microorganisms have been suggested to be associated with OLP in multiple investigations, implying that the functional aspects of the oral microbiota are more important in OLP development than the composition of the oral microbiota. According to studies on host factors that make up the oral environment, signal pathways involved in cellular processes, such as keratinization, inflammation, and T cell responses are triggered in OLP. Studies on the functional aspects of the oral microbiota, as well as interactions between the host and the oral microbiota, are still lacking, and more research is required.

Detection of Human Papillomavirus 33 in Erosive Oral Lichen Planus

Background: A correlation is suggested between oral lichen planus (OLP) and the human papillomavirus (HPV) with possible malignant transformation potential in OLP. Objectives: The present study aimed at evaluating the prevalence of HPV-16 and HPV-18 as the most recognized oncogenic subtypes and relatively recently introduced subtype HPV33 in OLP samples. Methods: This retrospective study was carried out on 32 OLP samples (consisting of 12 reticular and 20 erosive forms) and 20 healthy oral mucosa samples. Polymerase chain reaction (PCR) was undertaken to identify HPV Deoxyribonucleic Acid (DNA). Subsequently, the samples positive for HPV DNA underwent PCR analysis again with the specific primers. The data were analyzed statistically by Fisher’s exact test regarding the significance level of lower than 0.05. Results: Eight out of 32 OLP samples (25%) and none of the 20 normal mucosa samples (0%) exhibited HPV DNA. The presence of HPV in the OLP group was significantly higher than that in the normal mucosa (P = 0.014). Also, all the samples that exhibited HPV DNA were registered as the erosive form. Besides, one sample (3.12%) exhibited the 873-bp band, which was attributed to HPV-18, and 7 samples (21.87%) exhibited the 300-bp band, which was attributed to HPV-33. Conclusions: Based on the recent findings in the current study of the Iranian population, the presence of high-risk HPV subtypes, whether primarily or as a secondary infection, can suggest the malignant transformation potential for the studied OLP samples. The exclusive presence of these subtypes in the erosive type of this lesion and the noticeable presence of HPV-33 might reflect this issue’s importance. However, further studies are necessary to evaluate the possibility of a higher proliferation rate of HPV in erosive lichen planus and identify its possible malignant transformation mechanism.

Association of Human Papillomavirus With Oral Lichen Planus and Oral Leukoplakia: A Meta-analysis

OBJECTIVES

To estimate the association of human papillomavirus (HPV) infection with oral lichen planus (OLP) and oral leukoplakia (OLK), and determine risk cofactors.

STUDY DESIGN

Seven databases were searched for case-control or cross-sectional studies of OLP and OLK with healthy controls, published between 1976 and 2020. The Meta package of R software was applied to calculate the pooled odds ratios (OR) and 95% confidence interval (CI).

RESULTS

Thirty-six articles were finally included. OLP and OLK cases had a higher association with HPV infection than controls (OLP: OR: 4.91, 95% CI: 2.76-8.72; OLK: OR: 2.51, 95% CI: 1.55-4.07). In subgroup analyses, the OR of HPV infection was higher with erosive lesions than with nonerosive lesions (OLP: OR: 5.36 and 3.47, respectively; OLK: OR: 3.34 and 3.21, respectively). Oral lesions were more strongly associated with HPV16/18 than with HPV6/11 (OLP: OR: 7.84 and 1.42, respectively; OLK: OR: 6.05 and 1.87, respectively) and varied by geographic region (OLP: OR: 4.01-7.02; OLK: OR: 1.46-27.13).

CONCLUSIONS

Oral HPV infection, particularly infection with HPV 16/18, was strongly associated with OLP and OLK. Risk cofactors included erosive lesions and geographic region.

The association between Epstein-Barr virus and oral lichen planus: A systematic review and meta-analysis

BACKGROUND

Oral lichen planus (OLP) is a relatively common inflammatory disease, with unclear etiology. A number of studies have linked Epstein-Barr virus (EBV) with OLP. The present systematic review and meta-analysis aimed to evaluate the available evidence regarding the potential association between EBV and OLP.

METHODS

Online databases (PubMed, Scopus, Web of Science, ProQuest, and Google Scholar) were searched from date of inception till May 2020. Studies were included if they met the following criteria: 1) observational studies that assessed the relationship between EBV and OLP, 2) the study comprised OLP patients and control subjects, 3) diagnosis of OLP was confirmed histopathologically, and 4) articles were in English. Studies without control groups, experimental studies, case reports, and reviews were excluded. The fixed-effects model was performed for meta-analyses using RevMan 5.3 software.

RESULTS

A total of 10 studies comprising 386 OLP cases and 304 controls were included. Of these, only 8 studies were eligible for the meta-analysis. The results of the quality assessment showed that only 2 studies were of high quality, while the remaining studies were of moderate quality. The results of the pooled eight studies revealed a significant positive association between EBV and OLP (OR = 4.41, 95% CI: [2.74, 7.11], P < .0001).

CONCLUSION

The results of the present systematic review suggest that EBV infection is statistically associated with increased risk of OLP. However, these results are preliminary, and high-quality, large-scale studies are warranted to further explore the potential role of EBV in the pathogenesis of OLP.

The microbiology of oral lichen planus: Is microbial infection the cause of oral lichen planus?

Oral lichen planus (OLP) is a variant of lichen planus (LP), a common chronic mucocutaneous inflammatory disease. Cutaneous lesions of LP are self-limiting, but OLP lesions are non-remissive, alternating periods of exacerbation and quiescence, and only symptomatic treatments exist for OLP. The precise etiology and pathogenesis of OLP are hardly understood, which is a major obstacle to the development of new therapeutics for this disease. OLP is considered a T-cell-mediated inflammatory disease. Although various antigens have been considered, what actually triggers the inflammatory response of T cells is unknown. Suggested predisposing factors include genetic factors, stress, trauma, and infection. The aim of this review was to determine whether microbial infection can cause OLP. We first reviewed the association between OLP and microbial factors, including viral, fungal, and bacterial infections. In addition, each microbial factor associated with OLP was assessed by modified guidelines of Fredricks and Relman to determine whether it establishes a causal relationship. In conclusion, no microbial factor yet fulfills the guidelines to establish the causality of OLP. By focusing on the unclarified issues, however, the potential roles of microbial factors in the pathogenesis of OLP will be soon elucidated.

Human papillomavirus infection in oral potentially malignant disorders and cancer

Human papillomavirus (HPV) infects keratinocytes in the mucosa or skin, and persistent infection with HPV may lead to premalignant lesions and invasive cancer, especially cervical cancer. It has also been hypothesized that HPV infection is an etiological factor of oral squamous cell carcinoma and oral precancerous disorders such as lichen planus, leukoplakia, and erythroplakia. A high percentage of HPV in oral lesions supports the possible viral contribution, but an association of HPV infection with these lesions remains to be established. The current paper will update the latest progress of HPV infection in several oral potentially malignant disorders and oral squamous cell carcinoma and discuss the impact of HPV infection on the progression of oral potentially malignant disorders.

Association of classic lichen planus with human herpesvirus-7 infection

BACKGROUND

Lichen planus is a mucocutaneous papulosquamous itchy disease with unknown etiology. A number of factors such as immune mechanisms, viral agents, and drugs have been implicated in pathogenesis of lichen planus. In recent years, several studies have indicated the role of viral agents in this disease, including human herpesvirus-7 (HHV-7). Studies have given contradictory results, which is why we decided to study the possible association between lichen planus with HHV-7.

METHODS

In this case-control study, which was conducted on 60 cutaneous classic lichen planus samples as well as 60 healthy control skin samples after matching the two groups in terms of gender and age, tissue samples of patients and controls were studied by real time polymerase chain reaction to detect for HHV-7.

RESULTS

According to this study, HHV-7 DNA was found in 18 samples of the case group (30.0%) and in six (10.0%) of the control group (P = 0.006).

CONCLUSION

The results of this study support the likely role of HHV-7 in pathogenesis of lichen planus. As an exogenous antigen, this virus may be involved in cellular immune-mediated destruction of keratinocytes.

The Magnitude of the Association between Human Papillomavirus and Oral Lichen Planus: A Meta-Analysis

Background

The role of human papilloma virus (HPV) in oral lichen planus (OLP) is controversial.

Objectives

The primary aim of the current study is to calculate the pooled risk estimates of HPV infection in OLP when compared with healthy controls.

Methods

Bibliographic searches were conducted in three electronic databases. Articles on the association between HPV and OLP were selected from case-control studies or cross-sectional studies, following predefined criteria. Pooled data were analyzed by calculating odds ratios (OR) and 95% confidence interval (CI).

Results

Of the 233 publications identified, 22 case-control studies met the inclusion criteria. Collectively, 835 cases and 734 controls were available for analysis. The summary estimate showed that OLP patients have significantly higher HPV prevalence (OR: 6.83; 95% CI: 4.15–11.27) than healthy controls. In subgroup analyses, the association of HPV and OLP varied significantly by geographic populations. The ORs ranged from 2.43 to 132.04. The correlation of HPV and erosive-atrophic oral lichen planus (EA-OLP) (OR: 9.34) was comparable and well above that of HPV and non-EA-OLP (OR: 4.32). Among HPV genotypes, HPV 16 showed an extremely strong association with OLP (OR: 11.27), and HPV 18 showed a relatively strong one (OR: 6.54).

Conclusion

In conclusion, a significant association was found between HPV and OLP. The strength of the association varied across geographic populations, clinical types of OLP, and HPV genotypes. The results suggest that HPV might play an important causal role in OLP and in its malignant to progression.

Detection of Epstein-Barr virus in different sources of materials from patients with oral lichen planus: a case-control study

AIMS

To detect the presence of Epstein-Barr virus (EBV) DNA in different sources of materials from a matched group of patients with oral lichen planus (OLP) and a group of people without OLP lesions, and to correlate the presence of virus with epidemiological variables of the groups studied.

METHODS

Fresh tissue samples, saliva, exfoliated cells and plasma of 24 patients with OLP lesions (cases) and 17 patients without OLP lesions (controls) were collected. EBV was detected by nested PCR.

RESULTS

Viral positivity was obtained in 62.5% of tissue samples; in 70.8% of exfoliated cell samples; in 33.3% of blood plasma samples and in 75% of saliva samples in the cases; and in 35.3% of tissue samples; 82.4% of exfoliated cell samples; in 47.1% of blood plasma samples and in 64.7% of saliva samples in the controls. There was a predominance of women in both groups. Variables not atrophic-erosive were most affected by EBV.

CONCLUSIONS

No relationship between EBV and OLP was found. However, all sources tested in this study were considered suitable for the detection of viruses.

Role of human papillomavirus in oral squamous cell carcinoma and oral potentially malignant disorders: A review of the literature

Human papillomaviruses (HPVs) are epitheliotropic viruses with an affinity for keratinocytes and are principally found in the anogenital tract, urethra, skin, larynx, tracheobronchial and oral mucosa. On the basis of high, but variable frequency of HPV in oral squamous cell carcinoma (OSCC), malignant potential of HPV infection has been hypothesized but not definitely confirmed. The aim of this review was to highlight the genomic structure and possible mechanism of infection and carcinogenesis by HPV in the oral mucosa and to review the frequency of HPV prevalence in OSCC and oral potentially malignant disorders. A computer database search was performed through the use of PubMed from 1994 to 2014. Search keywords used were: HPV and oral cancer, HPV and oral leukoplakia, HPV and oral lichen planus, HPV and OSCC, HPV and verrucous carcinoma, HPV and proliferative verrucous leukoplakia, HPV and oral papilloma.

Prevalence of human papillomavirus in oral lichen planus in an Iranian cohort

CONTEXT

Oral lichen planus (OLP) is a chronic inflammatory mucocutaneous disease with female predominance with the potential for malignant transformation. Human papillomavirus (HPV) is associated with both malignant and benign disease in the head and neck region.

AIMS

The present study assesses the prevalence of high-risk HPV-16 and HPV-18 in tissue and saliva samples from an Iranian population diagnosed with OLP.

SUBJECTS AND METHODS

Deoxyribonucleic acid was extracted and investigated using polymerase chain reaction from tissue and saliva samples of the same individuals from 40 OLP cases and saliva samples of 40 healthy controls.

STATISTICAL ANALYSIS

The prevalence of data was compared using the Chi-square test and inter-group differences were analyzed using Fisher's exact test.

RESULTS

OLP specimens were HPV-positive in 11 of 40 (27.5%) cases compared with three of 40 (7.5%) saliva specimens, representing a statistically significant difference (P = 0.0367). HPV-16 and HPV-18 were positive in eight of 40 (20%) OLP tissues and three of 40 (7.5%) saliva samples. Five of the 40 healthy saliva samples were positive for HPV-16. In the OLP patients with dysplasia, four of seven tissue samples were HPV-positive; threeof these four were HPV-16- positive in comparision with seven of 33 HPV-positive samples from OLP patients without dysplasia.

CONCLUSIONS

Biopsies were more accurate than saliva analysis for evaluating HPV prevalence in OLP patients. HPV prevalence was higher in dysplastic than nondysplastic OLP lesions in this Iranian cohort.

A potential peptide pathway from viruses to oral lichen planus

Oral lichen planus is an idiopathic inflammatory disease of oral mucous membranes, characterized by an autoimmune epidermis attack by T cells. It remains unknown, however, how such aggressive T cells are activated in vivo to cause epidermal damage. This study analyzes the relationship at the peptide level between viruses and oral lichen planus disease. Four potentially immunogenic peptides (SSSSSSS, QEQLEKA, LLLLLLA, and MLSGNAG) are found to be shared between HCV, EBV, HHV-7, HSV-1, and CMV and three human proteins (namely pinin, desmoglein-3, and plectin). The described peptide sharing might be of help in deciphering the still unexplained immunopathogenic pathway that leads to oral lichen planus.

Oral lichen planus: focus on etiopathogenesis

Lichen planus is a chronic mucocutaneous inflammatory disease, which frequently affects the oral mucosa of white females over 40 years old. Its aetiology remains uncertain and the pathogenesis is still the object of much speculation. The present paper presents the most well known antigens, and describes the action of different cells and proteins associated with the development of that disease, as well as the possible agents involved with its malignant transformation. Different external agents, especially virus, and internal agents, like stress, and the heat shock protein antigen expression, associated or not, can alter the basal keratinocytes of the oral mucosa making them susceptible to apoptosis by CD8(+) cytotoxic T cell as well as activate matrix metalloproteinase and mast cell degranulation, which produce a great range of inflammatory mediators and cytokines determining the clinical onset of the disease. Regarding carcinogenesis, since it is a complex process and presents multifactorial origin, it is believed that there may be a synergism between intrinsic, such as inflammation mediators, and extrinsic agents (tobacco, alcohol, viral infections) for the OLP malignant transformation to occur. However, further studies are needed to better understand the origin, pathogenesis and process of malignant transformation of OLP.