Association of periodontitis with the risk of oral leukoplakia

Type 17 immune response promotes oral epithelial cell proliferation in periodontitis

OBJECTIVES

This study aims to investigate the effects of type 17 immune response on the proliferation of oral epithelial cells in periodontitis.

DESIGN

A time-dependent ligature induced periodontitis mouse model was utilized to explore gingival hyperplasia and the infiltration of interleukin 17A (IL-17A) positive cells. Immunohistochemistry and flow cytometry were employed to determine the localization and expression of IL-17A in the ligature induced periodontitis model. A pre-existing single-cell RNA sequencing dataset, comparing individuals affected by periodontitis with healthy counterparts, was reanalyzed to evaluate IL-17A expression levels. We examined proliferation markers, including proliferating cell nuclear antigen (PCNA), signal transducer and activator of transcription (STAT3), Yes-associated protein (YAP), and c-JUN, in the gingival and tongue epithelium of the periodontitis model. An anti-IL-17A agent was administered daily to observe proliferative changes in the oral mucosa within the periodontitis model. Cell number quantification, immunofluorescence, and western blot analyses were performed to assess the proliferative responses of human normal oral keratinocytes to IL-17A treatment in vitro.

RESULTS

The ligature induced periodontitis model exhibited a marked infiltration of IL-17A-positive cells, alongside significant increase in thickness of the gingival and tongue epithelium. IL-17A triggers the proliferation of human normal oral keratinocytes, accompanied by upregulation of PCNA, STAT3, YAP, and c-JUN. The administration of an anti-IL-17A agent attenuated the proliferation in oral mucosa.

CONCLUSIONS

These findings indicate that type 17 immune response, in response to periodontitis, facilitates the proliferation of oral epithelial cells, thus highlighting its crucial role in maintaining the oral epithelial barrier.

Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies

OBJECTIVE

The current studies have yielded inconclusive findings regarding the connection between periodontitis  and oral cancer (OC). Therefore, our goal is to elucidate this relationship.

MATERIALS AND METHODS

We conducted a thorough search of electronic databases (EMBASE, PubMed, Web of Science, and Cochrane Library) up to September 2023. The Newcastle-Ottawa Scale (NOS) was applied to assess study quality. To evaluate potential publication bias, both a funnel plot and Egger's test were employed. Additionally, a sensitivity analysis was conducted to explore the source of heterogeneity when the I2 statistic exceeded 50%.

RESULTS

This systematic review encompassed 16 studies, involving a total of 6,032 OC patients and 7,432 healthy controls. Our meta-analysis, incorporating data from nine studies, revealed a significant correlation between periodontitis and the risk of OC (OR [odds ratio] = 2.94, 95% CI [confidence interval] (2.13, 4.07); five studies, 6,927 participants; low certainty of evidence). Findings also suggested that individuals with more than 15 missing teeth may have a heightened risk of OC (OR = 1.91, 95% CI (1.01, 3.62)). Furthermore, clinical attachment loss (CAL) and decayed, missing, and filled teeth (DMFT) in OC patients were more pronounced compared to the control group (CAL, SMD = 1.94, 95% CI (0.22, 3.66); DMFT, SMD = 0.65, 95% CI (0.12, 1.18)).

CONCLUSION

Periodontitis may serve as a potential risk factor for OC. However, caution is warranted in interpreting these findings due to the substantial level of heterogeneity.

The emerging role of oral microbiota in oral cancer initiation, progression and stemness

Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy among the Head and Neck cancer. OSCCs are highly inflammatory, immune-suppressive, and aggressive tumors. Recent sequencing based studies demonstrated the involvement of different oral microbiota in oral cavity diseases leading OSCC carcinogenesis, initiation and progression. Researches showed that oral microbiota can activate different inflammatory pathways and cancer stem cells (CSCs) associated stemness pathways for tumor progression. We speculate that CSCs and their niche cells may interact with the microbiotas to promote tumor progression and stemness. Certain oral microbiotas are reported to be involved in dysbiosis, pre-cancerous lesions, and OSCC development. Identification of these specific microbiota including Human papillomavirus (HPV), Porphyromonas gingivalis (PG), and Fusobacterium nucleatum (FN) provides us with a new opportunity to study the bacteria/stem cell, as well as bacteria/OSCC cells interaction that promote OSCC initiation, progression and stemness. Importantly, these evidences enabled us to develop in-vitro and in-vivo models to study microbiota interaction with stem cell niche defense as well as CSC niche defense. Thus in this review, the role of oral microbiota in OSCC has been explored with a special focus on how oral microbiota induces OSCC initiation and stemness by modulating the oral mucosal stem cell and CSC niche defense.

Impact of dental restorations and removable prostheses on potentially malignant oral mucosal disorders in the general population

STATEMENT OF PROBLEM

Dental restorations and removable dental prostheses have been considered as risk factors for potentially malignant disorders of the oral mucosa. It remains unclear whether amalgam, composite resins, and prosthesis materials can induce potentially malignant disorders.

PURPOSE

The purpose of this clinical study was to determine the relationship between the presence of amalgam and composite resin restorations, crowns and fixed partial dentures, and removable prostheses in potentially malignant disorders.

MATERIAL AND METHODS

The data of 6041 participants in the population-based Studies of Health in Pomerania (SHIP) were accessed. Potentially malignant disorders had been clinically diagnosed by calibrated dentists and documented with photographs. Dental treatment was subdivided into restored and replaced teeth. Dental restorations were subclassified as buccal composite resin or amalgam restorations. Prosthetic treatment was subclassified into removable partial or complete prostheses and definitive restorations with crowns and fixed partial dentures.

RESULTS

In the maxilla, participants with removable prostheses had a higher incidence of potentially malignant disorders than participants not undergoing treatment with removable prostheses (OR 2.12; 95% CI: 1.08-4.18), but not in the mandible (OR 1.30; 95% CI: 0.67-2.53). The surfaces with composite resin restorations were associated with a slightly higher risk of mucosal lesions than those without the restorations (OR 1.04; 95% CI: 1.01-1.07). No significant association was found between amalgam restorations and mucosal lesions.

CONCLUSIONS

Participants with removable prostheses have a higher risk of potentially malignant disorders. Composite resin restorations are associated with a higher risk of mucosal lesions, whereas no significant association was found between amalgam restorations and mucosal lesions.

Feasibility of investigating the association between bacterial pathogens and oral leukoplakia in low and middle income countries: A population-based pilot study in India

BACKGROUND

Certain oral bacterial pathogens may play a role in oral carcinogenesis. We assessed the feasibility of conducting a population-based study in India to examine the distributions and levels of Porphyromonas gingivalis, Fusobacterium nucleatum and Prevotella intermedia in relation to oral leukoplakia (a potentially malignant disorder) and other participant characteristics.

METHODS

This exploratory case-control study was nested within a large urban Indian cohort and the data included 22 men and women with oral leukoplakia (cases) and 69 leukoplakia-free controls. Each participant provided a salivary rinse sample, and a subset of 34 participants (9 cases; 25 controls) also provided a gingival swab sample from keratinized gingival surface for quantitative polymerase chain reaction (qPCR).

RESULTS

Neither the distribution nor the levels of pathogens were associated with oral leukoplakia; however, individual pathogen levels were more strongly correlated with each other in cases compared to controls. Among controls, the median level of total pathogens was the highest (7.55×104 copies/ng DNA) among persons of low socioeconomic status. Salivary rinse provided better DNA concentration than gingival swab for qPCR analysis (mean concentration: 1.8 ng/μl vs. 0.2 ng/μl).

CONCLUSIONS

This study confirms the feasibility of population studies evaluating oral microbiome in low-resource settings and identifies promising leads for future research.

Prevalence and risk factors of potentially malignant disorders of the mucosa in the general population: Mucosa lesions a general health problem?

AIM

Oral cancer mostly develops from oral mucosa regions with morphological alterations transforming malignant. These visible precancerous mucosa lesions are named potentially malignant disorders (PMD). We aimed to analyze the prevalence of PMD and its risk factors for PMD in a population-based sample in Northern Germany.

MATERIAL AND METHODS

Data of 6078 individuals from the population-based Study of Health in Pomerania (SHIP) was used. PMD were photographically documented and periodontal health was assessed in a standardized procedure.

RESULTS

PMD were observed in 54 individuals (0.9%). The most prevalent PMD was homogenous leukoplakia (n = 37) followed by Lichen ruber (n = 9). Smoking (Odds Ratio (OR) 2.70; 95% confidence interval (CI): 1.24-5.87), male sex (OR 3.32; 95%-CI: 1.77-6.21), type 2 diabetes mellitus (OR 2.07; 95%-CI: 1.08-3.98) and body mass index (OR 1.09; CI 1.04-1.14) were significantly associated with PMD, with the corresponding area under the curve (AUC) being 0.696 (CI: 0.655; 0.737).

CONCLUSION

Our results suggest a clinically relevant prevalence of PMD in the population. We identified male sex, type 2 diabetes mellitus, current smoking, and obesity as risk factors. We recommend photographic documentation and intensified training of medical and dental staff to detect and monitor PMD.

Management of oral leukoplakia: a position paper of the Society of Oral Medicine, Chinese Stomatological Association

OBJECTIVE

The objective of this study was to develop the first edition of a Chinese evidence-based position paper on the management of oral leukoplakia (OLK).

STUDY DESIGN

The consultant group for drafting the position paper consisted of 31 oral medicine specialists and 2 evidence-based medicine specialists. English studies (searched in PubMed, EMBASE, and the Cochrane Library) and Chinese studies (searched in China National Knowledge Infrastructure and WanFang) published before January 2018 were used. The quality of the study was assessed using the Grading of Recommendations Assessment, Development, and Evaluation grid, and the strength of the recommendations was determined based on the results of 3 rounds of voting among the consultant group members using the Delphi method.

RESULTS

Twenty-two evidence-based guidelines for clinical management and monitoring of OLK were established in this position paper. A clinical path diagram for oral health practitioners was constructed based on the recommendations.

CONCLUSION

Current evidence suggests that management and monitoring of patients with OLK should be performed by experienced clinicians to control the lesion and for early detection of malignant transformation. However, all recommendations are based on evidence of low or extremely low quality and may require further modification as new evidence is produced.

Biosensor and Lab-on-a-chip Biomarker-identifying Technologies for Oral and Periodontal Diseases

Periodontitis is a complex multifactorial disease that can lead to destruction of tooth supporting tissues and subsequent tooth loss. The most recent global burden of disease studies highlight that severe periodontitis is one of the most prevalent chronic inflammatory conditions affecting humans. Periodontitis risk is attributed to genetics, host-microbiome and environmental factors. Empirical diagnostic and prognostic systems have yet to be validated in the field of periodontics. Early diagnosis and intervention prevents periodontitis progression in most patients. Increased susceptibility and suboptimal control of modifiable risk factors can result in poor response to therapy, and relapse. The chronic immune-inflammatory response to microbial biofilms at the tooth or dental implant surface is associated with systemic conditions such as cardiovascular disease, diabetes or gastrointestinal diseases. Oral fluid-based biomarkers have demonstrated easy accessibility and potential as diagnostics for oral and systemic diseases, including the identification of SARS-CoV-2 in saliva. Advances in biotechnology have led to innovations in lab-on-a-chip and biosensors to interface with oral-based biomarker assessment. This review highlights new developments in oral biomarker discovery and their validation for clinical application to advance precision oral medicine through improved diagnosis, prognosis and patient stratification. Their potential to improve clinical outcomes of periodontitis and associated chronic conditions will benefit the dental and overall public health.

Possible association of periodontal disease with oral cancer and oral potentially malignant disorders: a systematic review

Background: Periodontitis has been associated with several systemic diseases and medical conditions, including oral cancer (OC). However, most studies reporting an association between OC and periodontal disease have used different clinical and radiographic criteria to define periodontal disease. This review aimed to evaluate the currently available evidence to determine an association between periodontal disease (extension and severity), OC, and oral potentially malignant disorders (OPMDs).Material and methods: A systematic search of studies published up to August 2018 was performed following the PRISMA guidelines in the electronic databases MEDLINE (PubMed) and COCHRANE (OVID). A methodological evaluation was made using the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) checklist.Results: Eight studies (case-control, cross-sectional and cohort) were included. An increased clinical attachment loss, plaque index, bleeding on probing, and radiographic bone loss was found in patients with OC and OPMDs. Differences in the methodological characteristics, case definition used for periodontal diseases, and OC location did not allow estimating the odds ratio required to conduct a meta-analysis.Conclusion: Some studies suggest a positive relationship between periodontal disease, OC, and OPMDs; however, the currently available evidence is insufficient to draw solid conclusions.

Marginal linear gingival leukoplakia progressing to "ring around the collar"-An ominous sign of proliferative verrucous leukoplakia

BACKGROUND

Potentially malignant lesions of the gingiva may frequently present as well-demarcated white lesions confined to the marginal gingiva. These lesions often become thick and verrucoid and spread along the marginal gingiva to encircle the tooth. Some cases of marginal gingival leukoplakia, over time, progress to extensively involve the gingiva fulfilling the criteria for proliferative verrucous leukoplakia (PVL). The objective of this study is to raise awareness of this pattern of leukoplakia by reporting a series of cases of marginal gingival leukoplakia.

METHODS

An Institutional Review Board approved retrospective search of University of Florida and University of Nebraska Medical Center oral biopsy services was performed for all gingival biopsies. Inclusion criteria included cases exhibiting marginal gingival leukoplakia, and with accompanying clinical images.

RESULTS

A total of 30 cases of marginal gingival leukoplakia were included. All cases presented as well-demarcated leukoplakias, either on the buccal or lingual gingival margin, or circumferentially forming a "ring around the collar" of single or multiple teeth. Eight patients had recurrent lesions and 12 had multifocal involvement. Six of the 12 patients with multifocal involvement presented with a "ring around the collar." The histopathologic diagnoses were representative of benign lesions in seven cases, premalignant in 13, and malignant or suggestive of malignancy in 10 cases. Seven patients had carcinoma at the time of first biopsy, whereas 6 cases showed progression at time of follow-up.

CONCLUSION

This study aims to raise awareness that marginal gingival leukoplakia may represent potentially malignant lesions, and if circumferential and/or thick, may be the first manifestation of PVL.

Association between p62 expression and clinicopathological characteristics in oral leukoplakia

Objective

Oral leukoplakia is keratinized lesions in the buccal mucosa, tongue, and gingiva. It is the most common oral precancerous lesion; oxidative stresses and irrelevant autophagy have been reported to be the cause of oncogenesis. p62, a cytoplasmic protein induced by oxidative stress, is an adaptor protein involved in the formation of protein aggregates and induction and inhibition of autophagy. The inhibition of autophagy induces p62 overexpression and promotes oncogenesis via the oncogenic signaling pathway. The aim of the present study was to elucidate the involvement of intracellular expression of p62 in oral leukoplakia and to address its potential clinical implementation as a biomarker to predict malignant transformation.

Material and Methods

Fifty samples from subjects with confirmed oral leukoplakia were evaluated by immunohistochemical staining for the expression of p62, 8-hydroxy-2'-deoxyguanosine (8-OHdG), Ki67, and p53. Univariate and multivariate logistic regression analyses were performed to evaluate the association between p62, 8-OHdG, Ki67, and p53 and clinical characteristics, including epithelial dysplasia.

Results

Significant associations were observed between p62 expression in the nucleus, p62 aggregation, and epithelial dysplasia (adjusted odds ratio [OR] = 5.75; 95% confidence interval [CI]: [1.28, 26.2]; .024 and OR = 6.16; 95% CI: [1.01, 37.4]; .048, respectively). The expression of p62 in the cytoplasm and the levels of 8-OHdG, Ki67, and p53 were not significantly associated with epithelial dysplasia. A significant relationship was found between p62 expression in the nucleus and p53 expression (OR = 3.94; 95% CI: [1.14, 13.6]; .031).

Conclusions

The results suggested that p62 expression in the nucleus and p62 aggregation can be potential markers to predict the malignant transformation of oral leukoplakia.

A retrospective analysis of the prevalence of dental diseases in patients with digestive system cancers

The relationship between dental diseases and the prevalence of digestive system cancers remains unclear. The aim of the present study was to examine the prevalence of dental diseases in patients treated for digestive system cancers.The medical and dental records of patients treated for digestive system cancers were retrospectively reviewed, and the results obtained (decayed/filled/missing teeth [DMFT] indices and community periodontal index [CPI] codes) were compared with data from the national survey of dental diseases in order to investigate the relationship between oral health and digestive system cancers.DMFT, D, and F indices were significantly lower, while the M index was slightly higher in digestive system cancer patients than in the national survey. The proportions of individuals with more than 20 residual teeth and denture wearers were significantly lower in cancer patients than in the national survey. The prevalence of periodontitis (CPI codes 3 and 4) and severe periodontitis (CPI code 4) were significantly higher in cancer patients than in the national survey.The present results showed that digestive system cancers were closely associated with multi-tooth loss and/or a low denture-wearing rate. The prevalence of severe periodontitis was also found to be higher in cancer patients. These results suggest that periodontitis and associated multi-tooth loss play a potential role in digestive system cancers.

Is Periodontitis Independently Associated with Potentially Malignant Disorders of the Oral Cavity?

Objective:

To examine if periodontitis is independently associated with oral potentially malignant disorders (OPMD) in a rural Indian adult population aged 35-54 years.

Methods:

A population-based cross-sectional study was conducted in rural India from 2011 to 2012. Multistage stratified cluster random sampling was followed to recruit 1401 participants aged 35-54 years. Face-to-face interviews were conducted to collect data on sociodemographic factors, tobacco and alcohol use. Oral examinations were done to record OPMD, periodontal findings and missing teeth. Univariate, bivariate and multivariable analyses were achieved using SPSS version 16 Chicago, SPSS Inc. OPMDs (leukoplakia, erythroplakia, oral submucous fibrosis (OSF) and suspicious malignant lesion) whether present or absent were selected as outcome variables; age, sex, socioeconomic factors, smoking, tobacco-chewing status, alcohol use, and periodontitis were considered as the predictor variables.

Results:

Among 873 participants, 44 demonstrated 47 lesions. Leukoplakia (n=21), erythroplakia (n=3), OSF (n=21), and suspicious malignant lesions (n=2) were present, strongly associated with past tobacco-chewing status [OR=9.22 (2.57-33.15)], current tobacco-chewing status [OR=15.49 (6.20-38.74)] and moderate/severe periodontitis [OR=3.19 (1.11-9.12)].

Conclusion:

Periodontitis is a risk indicator for OPMD, independent of socioeconomic factors and tobacco-chewing. Tobacco-chewing status, both past and current, was strongly associated with OPMD in our rural Indian population.

Photodynamic therapy in the treatment of oral leukoplakia: A systematic review

OBJECTIVE

The aim of the present study was to systematically review the efficacy of photodynamic therapy (PDT) in the management of oral leukoplakia (OLK).

METHODS

This systematic review aimed to address the following focused question: "Is photodynamic therapy effective in the management of oral leukoplakia?'' PubMed/Medline, EMBASE, ISI Web of Knowledge, OVID, CNKI, and WANFANG DATA were searched up to and including June 2018 using different combinations of the following keywords: photodynamic therapy, leukoplakia, oral dysplasia, oral precancers, and oral premalignant lesions.

RESULTS

Sixteen studies were included in the present study. A total of 352 patients was included in this review, with age ranging from 20 to 79 years. Photosensitizers used were aminolevulinic acid, Photofrin, methylene blue, and chlorine-e6. Laser wavelength, duration of irradiation, and power density were 420-660 nm, 60-1000 s, and 100-150 mW/cm², respectively. On the whole, the rates of complete response and partial response were 32.9% and 43.2%, and the sum was 76.1%. The follow-up period ranged from 1 month to 119 months. The recurrence rate of OLK was 0-60%.

CONCLUSION

PDT appears to be a useful therapeutic strategy in the management of oral leukoplakia as a non-surgical treatment. Further RCTs with long follow-up period, standardized PDT parameters, and comparing efficacy of PDT with various other therapies are needed to acquire definite conclusions.

Chicken or the Egg: Microbial Alterations in Biopsy Samples of Patients with Oral Potentially Malignant Disorders

Oral carcinogenesis often leads to the alteration of the microbiota at the site of the tumor, but data are scarce regarding the microbial communities of oral potentially malignant disorders (OPMDs). Punch biopsies were taken from healthy and non-healthy mucosa of OPMD patients to analyze the microbiome using metagenome sequencing. In healthy oral mucosa biopsies the bacterial phyla Firmicutes, Fusobacteria, Proteobacteria, Actinobacteria and Bacteroidetes were detected by Ion Torrent sequencing. The same phyla as well as the phyla Fibrobacteres and Spirochaetes were present in the OPMD biopsies. On the species level, there were 10 bacterial species unique to the healthy tissue and 35 species unique to the OPMD lesions whereas eight species were detected in both samples. We observed that the relative abundance of Streptococcus mitis decreased in the OPMD lesions compared to the uninvolved tissue. In contrast, the relative abundance of Fusobacterium nucleatum, implicated in carcinogenesis, was elevated in OPMD. We detected markedly increased bacterial diversity in the OPMD lesions compared to the healthy oral mucosa. The ratio of S. mitis and F. nucleatum are characteristically altered in the OPMD lesions compared to the healthy mucosa.

Oral microbiome, periodontitis and risk of head and neck cancer

A wide range of studies has been successfully exploring the association between the human microenvironment, sustained inflammation, and cancer. Growing evidence has then emerged in this field over the past few years. Nevertheless, reliable data addressing the impact of the oral microbiome and periodontitis on the pathogenesis and risk of head and neck malignancies remain scarce. Hence, this communication focuses on briefly discuss the relationship between the oral microbiome, periodontitis and head and neck cancer based on the current understanding of such a disease-associated scenario.

Is there a relationship between periodontal disease and oral cancer? A systematic review of currently available evidence

Oral cancer (OC) is known to have a multi-factorial etiology; tobacco, alcohol and betel quid being the major risk factors. Tooth loss and periodontal disease (PD) have been implicated to increase the risk of developing various cancers. The aim of this systematic review was to assess any possible association between PD and OC. Indexed databases were searched using different combinations of the following key words: "oral cancer", "periodontal disease", "tooth loss", "squamous cell carcinoma", "missing teeth" "alveolar bone loss", "clinical attachment loss" and "periodontitis". PRISMA criteria were followed to accrue data and databases were searched from 1984 up to and including June 2015. In total, 12 case-control studies were selected from the published literature.

RESULTS

Nine studies reported a 2-5 fold increase in the risk of OC among patients with PD as compared to those without PD. Three studies reported no association between PD and OC. In one study, an increased risk of tongue cancer was associated with each millimeter of alveolar bone loss and in two studies clinical attachment loss of more than 1.5mm was associated with an increased risk of OC. In studies reporting significant findings these associations persisted after adjusting for major risk factors. PD is associated with a small but significant increase in risk for OC. In several reported studies this association was attenuated following adjustment for tobacco and alcohol use.

An inverse association of Helicobacter pylori infection with oral squamous cell carcinoma

BACKGROUND

Few studies have focused on the relationship between Helicobacter pylori (H. pylori) infection and oral diseases. In this study, we explored the correlation between H. pylori infection and oral squamous cell carcinoma (OSCC).

METHODS

A total of 68 patients with OSCC and 104 age- and sex- matched healthy control subjects were retrospectively enrolled in this study. The H. pylori immunoglobin (Ig) G antibodies in serum were detected by enzyme-linked immunosorbent assay (ELISA) method to assess the status of H. pylori infection of our study sample. Polymerase chain reaction (PCR) was also employed using H. pylori genus-specific 16S rRNA primers in fasting blood, and OSCC specimens were analyzed by histochemical stain of each enrolled subject. The strength of correlation between H. pylori and the development of OSCC was estimated by Spearman's correlation coefficient.

RESULTS

According to the three methods for detecting prevalence of H. pylori infection in the patients with OSCC, it was statistically lower than that in the healthy controls (35.3% vs. 54.8%, P = 0.012). An inverse correlation was observed between H. pylori infection and OSCC development (Spearman's correlation coefficient = -0.191, P = 0.012). In stratification analysis, we also found a statistical association between H. pylori infection and OSCC in the subpopulation with age ≥ 60 years (P = 0.037).

CONCLUSION

Our findings suggested that H. pylori infection may be negatively related to OSCC. A reverse association of H. pylori infection with OSCC risk in the subpopulation with age ≥ 60 years was also found.

The Correlation between Chronic Periodontitis and Oral Cancer

Infections are increasingly considered as potential trigger for carcinogenesis apart from risk factors like alcohol and tobacco. The discussion about human papilloma virus (HPV) in oral squamous cell carcinoma (OSCC) points at a general role of infection for the development of oral carcinomas. Furthermore, first studies describe a correlation between chronic periodontitis and OSCC, thus, characterizing chronic inflammation as being a possible trigger for OSCC. In front of this background, we present four well-documented clinical cases. All patients showed a significant anatomical relation between OSCC and clinical signs of chronic periodontitis. The interindividual differences of the clinical findings lead to different theoretical concepts: two with coincidental appearance of OSCC and chronic periodontitis and two with possible de novo development of OSCC triggered by chronic inflammation. We conclude that the activation of different inflammatory cascades by chronic periodontitis negatively affects mucosa and bone. Furthermore, the inflammatory response has the potential to activate carcinogenesis. Apart from a mere coincidental occurrence, two out of four patients give first clinical hints for a model wherein chronic periodontitis represents a potential risk factor for the development of OSCC.

Serum levels of chemokine (C-X-C motif) ligand 9 (CXCL9) are associated with tumor progression and treatment outcome in patients with oral cavity squamous cell carcinoma

OBJECTIVES

The aim of this cohort study was to examine the role of chemokine (C-X-C motif) ligand 9 (CXCL9) on oral cavity squamous cell carcinoma (OSCC).

METHODS

Sera from 181 OSCC patients, 231 healthy individuals, and 50 OSCC tumor samples were enrolled. CXCL9 expression in tissue samples was analyzed by quantitative real-time PCR and immunohistochemistry. CXCL9 serum concentrations were measured by enzyme-linked immunosorbent assay. Effects of CXCL9 on OSCC cell function were investigated by cell proliferation assays, trans-well migration/invasion assays, and RNA interference.

RESULTS

CXCL9 expression was significantly higher than for normal epithelium in the tissue samples. CXCL9 serum concentrations were also significantly higher in OSCC patients compared to those in healthy individuals. Serum CXCL9 levels were significantly higher in OSCC patients with higher pT status, pathological overall stages, tumor depths, and positive bone invasion (P = 0.033, 0.004, 0.041, and 0.002, respectively). Moreover, OSCC patients with higher CXCL9 levels (> 209 pg/mL, median level) before treatment had worse prognoses for overall survival and disease-specific survival (P = 0.0006 and 0.0009, respectively). Multivariate logistic regression analyses also indicated that higher CXCL9 serum levels were an independent prognostic factor for overall survival and disease-free survival (P = 0.003 and 0.004, respectively). The in vitro suppression of CXCL9 expression in SCC25 cells using specific interfering RNAs attenuated cell proliferation, migration and invasiveness.

CONCLUSIONS

Our study demonstrated that CXCL9 is associated with tumor burden and aggressiveness of OSCC tumors and serum level of this ligand may be useful as a prognostic indicator.

Oral human papillomavirus detection in older adults who have human immunodeficiency virus infection

OBJECTIVE

To evaluate reproducibility of oral rinse self-collection for human papillomavirus (HPV) detection and investigate associations between oral HPV, oral lesions, immune and sociodemographic factors, we performed a cross-sectional study of older adults with human immunodeficiency virus (HIV) infection.

STUDY DESIGN

We collected oral rinse samples from 52 subjects at 2 different times of day, followed by an oral examination and interview. We identified HPV with the use of polymerase chain reaction platforms optimized for detection of mucosal and cutaneous types.

RESULTS

Eighty-seven percent of individuals had oral HPV, of which 23% had oncogenic alpha, 40% had nononcogenic alpha, and 46% had beta or gamma HPV. Paired oral specimens were concordant in all parameters tested. Significant associations observed for oral HPV with increased HIV viral load, hepatitis C seropositivity, history of sexually transmitted diseases, and lifetime number of sexual partners.

CONCLUSIONS

Oral cavity may be a reservoir of subclinical HPV in older adults who have HIV infection. Understanding natural history, transmission, and potential implications of oral HPV warrants further investigations.