High prevalence of hepatitis C virus antibody and RNA in patients with oral cancer

Network pharmacology integrated molecular docking of fucoidan against oral cancer and in vitro evaluation- A study using GEO datasets

Oral cancer is a widespread health concern in rural India due to a lack of awareness, delayed diagnosis and limited access to affordable treatment options. The current chemotherapy has notable side effects, underscoring the need for new drug candidates with improved bioavailability and specificity. In this current research, fucoidan, a sulphated polysaccharide, was extracted from the brown algae Spatoglossum asperum, and shown to be cytotoxic in vitro against oral cancer cells (KB cell line) at an IC50 of 107.76 µg/ml, suggesting its potential as a drug candidate. This study further aimed to explore the potential therapeutic implications of fucoidan in managing oral cancer using network pharmacology. PharmMapper, Comparative Toxicogenomics Database and SuperPred were initially used to identify fucoidan protein targets. The identified targets were further screened against Gene Expression Omnibus (GSE23558, GSE25099 and GSE146483), OMIM, TCGA and GeneCards datasets to identify oral cancer-specific protein targets. The interactions between the selected proteins were visualised using STRING and Cytoscape. Subsequently, Database for Annotation, Visualization and Integrated Discovery was used for gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of candidate targets. The cancer-related network was assessed using CancerGeneNet, while life expectancy based on the expression of the top 10 CytoHubba ranked hub genes was evaluated using Kaplan-Meier plots. Finally, EGFR, AKT1, HSP90AA1 and SRC were selected for docking and molecular dynamics simulation with fucoidan, using Maestro and GROMACS, respectively.Communicated by Ramaswamy H. Sarma.

Is Systemic Immunosuppression a Risk Factor for Oral Cancer? A Systematic Review and Meta-Analysis

Even if the relationship between immunosuppression and increased incidence of systemic cancers is well known, there is less awareness about the risk of developing oral cancer in immunosuppressed patients. The aim of this review was to evaluate the association between immunosuppression and the development of oral cancer. Two authors independently and, in duplicate, conducted a systematic literature review of international journals and electronic databases (MEDLINE via OVID, Scopus, and Web of Science) from their inception to 28 April 2023. The assessment of risk of bias and overall quality of evidence was performed using the Newcastle-Ottawa Scale and GRADE system. A total of 2843 articles was identified, of which 44 met the inclusion criteria and were included in either the qualitative or quantitative analysis. The methodological quality of the included studies was generally high or moderate. The quantitative analysis of the studies revealed that immunosuppression should be considered a risk factor for the development of oral cancer, with a percentage of increased risk ranging from 0.2% to 1% (95% CI: 0.2% to 1.4%). In conclusion, the results suggest that a constant and accurate follow-up should be reserved for all immunosuppressed patients as a crucial strategy to intercept lesions that have an increased potential to evolve into oral cancer.

Impact of Interferon-Free Direct-Acting Antivirals on the Incidence of Extrahepatic Malignancies in Patients with Chronic Hepatitis C

BACKGROUND

The incidence of extrahepatic malignancies (EHMs) after hepatitis C virus (HCV) eradication by interferon (IFN)-based and IFN-free direct-acting antivirals (DAAs) treatment remains unclear.

AIMS

The aim was to evaluate the cumulative incidence of EHMs diagnosed for the first time after the antiviral treatments.

METHODS

We analyzed a total 527 patients with chronic HCV infection and without prior history of any malignancies who achieved sustained virological response by antiviral treatments, including IFN-based (n = 242) or IFN-free DAAs (n = 285). The baseline predictors for EHM occurrence were analyzed using Cox regression analysis.

RESULTS

Thirty-two patients were diagnosed with EHMs, 14 in IFN-based and 18 in IFN-free DAAs, respectively. The total duration of follow-up was 1,796 person-years in IFN-based and 823 person-years in IFN-free DAAs. The incidence of EHMs in IFN-based and IFN-free DAAs was 7.8 and 21.9 per 1,000 person-years, respectively. The cumulative incidence of EHMs was significantly higher in IFN-free DAAs than IFN-based (p = 0.002). IFN-free DAAs was a single independent predictor for incidence of EHMs (p = 0.012). As for gender, the incidence of EHMs was significantly higher in IFN-free DAAs only in the female cohort (p = 0.002). After propensity score matching, IFN-free DAAs was a single independent predictor for incidence of EHMs in the female patients (p = 0.045).

CONCLUSIONS

The incidence of EHMs after HCV eradication is higher in IFN-free DAAs than IFN-based regimens, especially in female patients. We should carefully follow-up not only HCC but also EHMs after IFN-free DAAs regimens.

Mac-2-binding protein glycan isomer predicts all malignancies after sustained virological response in chronic hepatitis C

Despite reports of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C virus (HCV) infection after achieving sustained virological response (SVR), only few studies have demonstrated the incidence of other (non-HCC) malignancies. This study aimed to clarify the incidence, survival probability, and factors associated with malignancy, especially non-HCC malignancies, in patients with chronic HCV infection after achieving SVR. In this retrospective study, records of 3580 patients with chronic HCV infection who achieved SVR following direct-acting antiviral (DAA) treatment were analyzed. The cumulative post-SVR incidence of non-HCC malignancies was 0.9%, 3.1%, and 6.8% at 1, 3, and 5 years, respectively. The survival probability for patients with non-HCC malignancies was 99.1%, 78.8%, and 60.2% at 1, 3, and 5 years, respectively, and the rate was significantly lower than that for patients with HCC. The Cox proportional hazards regression model identified Mac-2-binding protein glycan isomer (M2BPGi) cutoff index (COI) ≥ 1.90 at baseline and ≥ 1.50 at 12 weeks following DAA treatment as significant and independent factors associated with the post-SVR incidence of non-HCC malignancies. Furthermore, patients with either M2BPGi COI ≥ 1.90 at baseline or M2BPGi COI ≥ 1.50 at SVR12 had a significantly higher risk of post-SVR incidence of non-HCC malignancies than of HCC. Conclusion: M2BPGi measurements at baseline and SVR12 may help predict the post-SVR incidence of non-HCC malignancies in patients with chronic HCV infection who achieved SVR following DAA treatment. Early identification of these patients is critical to prolong patient survival.

Effects of Hepatitis C Virus Elimination by Direct-Acting Antiviral Agents on the Occurrence of Oral Lichen Planus and Periodontal Pathogen Load: A Preliminary Report

Objective

The association between hepatitis C virus (HCV) and oral lichen planus (OLP) is well known, but the association with periodontal disease has been reported less often. The purpose of this study was to investigate the effects of periodontal bacteria and OLP lesions before and after HCV elimination. Subjects and Methods. The subjects were four OLP patients (mean age 72.5 years) with HCV infection. Six types of periodontal bacteria (Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Fusobacterium nucleatum) were quantified in saliva, and changes in OLP were examined before and after elimination of HCV by antiviral therapy. Biochemical blood tests also were performed.

Results

The total number of periodontal bacteria, the numbers of P. gingivalis, T. forsythia, T. denticola, and F. nucleatum, and the risk of presenting with the red-complex bacteria (P. gingivalis, T. forsythia, and T.denticola), leading to periodontal disease progression, decreased after HCV elimination. OLP disappeared in three of the four patients and decreased in the other after sustained virological responses (SVRs).

Conclusion

HCV elimination not only improved OLP lesions but also reduced the number of periodontal pathogens and the amount of red-complex periodontal pathogens.

Implications of viral infection in cancer development

Since the identification of the first human oncogenic virus in 1964, viruses have been studied for their potential role in aiding the development of cancer. Through the modulation of cellular pathways associated with proliferation, immortalization, and inflammation, viral proteins can mimic the effect of driver mutations and contribute to transformation. Aside from the modulation of signaling pathways, the insertion of viral DNA into the host genome and the deregulation of cellular miRNAs represent two additional mechanisms implicated in viral oncogenesis. In this review, we will discuss the role of twelve different viruses on cancer development and how these viruses utilize the abovementioned mechanisms to influence oncogenesis. The identification of specific mechanisms behind viral transformation of human cells could further elucidate the process behind cancer development.

The role of dentists in controlling hepatocellular carcinoma in Japan (Review)

In Japan, the method of treatment for hepatitis is well established due to the high rates of hepatitis C. However, the identification of patients with hepatitis who do not receive appropriate treatment poses a major problem. Some patients with this disease may need to consult with a dentist due to the development of extrahepatic manifestations, such as lichen planus, in the oral cavity. Alternatively, the dentist might discover patients with untreated hepatitis C and hepatitis B during routine dental examination. In such cases, the patient should be referred to a hepatologist for further examinations and treatment. Thus, dentists are required to act as 'gatekeepers of hepatitis'. Furthermore, Japanese dentists need to increase hepatitis B vaccine coverage for infection control. By acting as a 'care coordinator of hepatitis', the dentist will be able to contribute to the eradication of liver cancer in Japan, thereby eliminating the discrimination and prejudice against patients with hepatitis. Dentists need to have a deep understanding of liver disease from the viewpoints of both nosocomial infection control and treatment of oral diseases.

Extrahepatic Malignancy Among Patients With Chronic Hepatitis C After Antiviral Therapy: A Real-World Nationwide Study on Taiwanese Chronic Hepatitis C Cohort (T-COACH)

INTRODUCTION

Chronic hepatitis C virus (HCV) infection is associated with nonhepatocellular carcinoma malignancies. We aimed to evaluate whether achieving a sustained virological response (SVR, defined as HCV RNA seronegativity throughout posttreatment 24-week follow-up) could reduce the risk of non-hepatocellular carcinoma malignancy in a real-world nationwide Taiwanese Chronic Hepatitis C Cohort (T-COACH).

METHODS

A total of 10,714 patients with chronic hepatitis C who had received interferon-based therapy (8,186 SVR and 2,528 non-SVR) enrolled in T-COACH and were linked to the National Cancer Registry database for the development of 12 extrahepatic malignancies, including those with potential associations with HCV and with the top-ranking incidence in Taiwan, over a median follow-up period was 3.79 years (range, 0-16.44 years).

RESULTS

During the 44,354 person-years of follow-up, 324 (3.02%) patients developed extrahepatic malignancies, without a difference between patients with and without SVR (annual incidence: 0.69% vs 0.87%, respectively). Compared with patients with SVR, patients without SVR had a significantly higher risk of gastric cancer (0.10% vs 0.03% per person-year, P = 0.004) and non-Hodgkin lymphoma (NHL) (0.08% vs 0.03% per person-year, respectively, P = 0.03). When considering death as a competing risk, non-SVR was independently associated with gastric cancer (hazard ratio [HR]/95% confidence intervals [CIs]: 3.29/1.37-7.93, P = 0.008). When patients were stratified by age, the effect of SVR in reducing gastric cancer (HR/CI: 0.30/0.11-0.83) and NHL (HR/CI: 0.28/0.09-0.85) was noted only in patients aged <65 years but not those aged >65 years.

DISCUSSION

HCV eradication reduced the risk of gastric cancer and NHL, in particular among younger patients, indicating that patients with chronic hepatitis C should be treated as early as possible.

Herpesviruses in Head and Neck Cancers

Head and neck cancers arise in the mucosa lining the oral cavity, oropharynx, hypopharynx, larynx, sinonasal tract, and nasopharynx. The etiology of head and neck cancers is complex and involves many factors, including the presence of oncogenic viruses. These types of cancers are among the most common cancers in the world. Thorough knowledge of the pathogenesis of viral infections is needed to fully understand their impact on cancer development.

Antiviral therapy against chronic hepatitis C is associated with a reduced risk of oral cancer

To identify the risk factors of oral cancer, we investigated the association between chronic hepatitis C (CHC) and oral cancer, and the development of oral cancer after anti-hepatitis C virus (HCV) therapy. We conducted a nationwide, population-based cohort study from 2004 to 2012 from the Taiwan National Health Insurance Research Database. CHC patients without anti-HCV therapy were matched with those non-HCV patients by age, sex and comorbidities. Moreover, CHC patients who underwent pegylated interferon and ribavirin (PegIFN/RBV) anti-HCV therapy were matched with CHC patients without anti-HCV therapy. A total of 100,058 patients were included in the HCV cohort and non-HCV cohorts, respectively. Their mean age was 59 years and 50% of these were male. CHC infection significantly increased the cumulative incidence of lichen planus and oral cancer. After adjustment for confounders and competing mortality, CHC infection significantly increased the risk of oral cancer (hazard ratio [HR]: 1.677, 95% confidence interval [CI]: 1.392-2.020, p < 0.001). Another 23,735 CHC patients without anti-HCV therapy were matched with 23,735 CHC patients in the treatment cohort. After adjustment for confounders and competing for mortality, the risk of oral cancer was significantly reduced in CHC patients receiving anti-HCV therapy (HR: 0.652, 95% CI: 0.479-0.887, p = 0.007). To minimize the inclusion of pre-existing unidentified oral cancer, we excluded oral cancer developed within the first year of CHC or anti-HCV therapy and found these associations remained statistically significant. In conclusion, CHC significantly increases the risk of oral cancer. Moreover, PegIFN/RBV antiviral therapy significantly reduces the risk of HCV-related oral cancer.

Red complex periodontal pathogens are risk factors for liver cirrhosis

Periodontal disease has been associated with liver disease; however, the identities of the periodontal disease-causing bacteria in patients with viral liver disease remain unknown. The aim of the present study was to determine the counts of the 3 periodontal pathogens that form the red complex in chronic periodontitis (Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola) and 3 other bacteria (Aggregatibacter actinomycetemcomitans, Prevotella intermedia and Fusobacterium necrophorum) in patients with liver disease. A total of 47 patients with liver disease were divided into two groups based on the counts of the red complex bacteria: group A (high counts of red complex bacteria) and group B (low counts of red complex bacteria). The counts of the 6 types of bacteria in saliva and the prevalence of P. gingivalis-specific fimA genotype were determined. In addition, salivary occult blood tests and serological assays were performed. Univariate and multivariate logistic regression analyses were used to analyze the risk factors between the two groups of patients. Hepatitis C virus-related liver disease was the most frequent (41/47; 87.2%) occurrence followed by liver cirrhosis (LC; 12/47; 25.5%) and oral lichen planus (32/47; 68.1%). The significant risk factors between the two groups were LC, albumin (Alb) level, ratios of each bacteria and prevalence of the fimA II genotype. The 3 factors identified in the multivariate analysis to be associated with the red complex bacteria count were low Alb level (<3.7 g/dl), LC and fimA II genotype, with adjusted odds ratios of 6.93, 4.72 and 4.08, respectively (P<0.05). These data indicated that patients with LC were at increased risk of presenting with the red complex bacteria leading to periodontal disease progression. Therefore, these patients may need to take additional care of their oral health compared with patients without LC, which may prove beneficial for the maintenance of their general health.

Prevalence of hepatitis C virus infection and its impact on the prognosis of head and neck cancer patients

OBJECTIVE

Several studies have shown a higher prevalence of hepatitis C virus (HCV) infection among patients with head and neck cancer (HNC) compared to the general population. In Brazil, the prevalence of HCV infection is considered low (1.38%). The aim of this study was to determine HCV prevalence and how this can modify outcomes of patients with HNC.

STUDY DESIGN

Retrospective cohort.

METHODS

Patients with a diagnosis of malignant neoplasm in the head and neck (HN) region and who had serology performed for HCV were included. Patients were classified into two groups: head and neck squamous cell carcinoma (HNSCC) and other head and neck malignant neoplasms (OHNMN). Descriptive statistics were performed for all variables of interest. Means were compared using ANOVA and proportions using chi-square tests. Survival data were compared by Kaplan-Meier curves and log-rank test.

RESULTS

Global HCV prevalence in patients with HNC was 7.8%, reaching 12.8% in HNSCC and 3.4% in OHNMN (p = 0.003). There was a higher risk of developing a second primary neoplasm in HNSCC compared to OHNMN patients (20.6% versus 4.6%; p = 0.001). The mean survival was not different between HCV-positive and HCV-negative patients (6.0 years versus 6.6 years, respectively, p = 0.516).

CONCLUSION

The prevalence of HCV infection was higher in HNC patients compared to the general Brazilian population. It seems reasonable to consider that HCV infection is associated with an increased risk of HNC, but HCV infection does not worsens the prognosis of HNC patients.

Hepatitis C Infection and Periodontal Disease: Is there a Common Immunological Link?

Hepatitis C virus (HCV) infections could have an important impact on the oral health status of patients, favoring conditions such as periodontal disease and oral cancer. The review of the existing scientific literature written in English was performed, searching for oral and periodontal manifestations of HCV infection and its impact on the oral fluids. HCV infection can determine direct extrahepatic manifestations at the oral and periodontal level including oral lichen planus, Sjögren-like sialadenitis, and oral cancer. The changes caused by the infection in the subjects' immune system, diet, and lifestyle can facilitate the development of oral conditions such as periodontal disease. Important changes also occur in the composition of the infected patients' saliva and gingival fluid. HCV-infected patients need to be carefully monitored in terms of oral health since the infection with the virus can result in oral complications. The cellular and molecular particularities of the gingival fluid of HCV-infected patients can answer some questions regarding its impact upon periodontium impairment and whether this refers to a possible bidirectional relationship, with hepatic biomarker adjustments being induced by the periodontal patients' inflammatory status.

Risk of malignancies in autoimmune hepatitis type 1 patients with a long-term follow-up in Japan

AIM

The risk of malignancies in autoimmune diseases is high and is regarded to be due to immunological abnormalities, the use of immunosuppressive agents, and/or chronic inflammation. The aim of this study was to investigate the incidence and risk of malignancies in patients with autoimmune hepatitis (AIH) type 1 in Japan.

METHODS

Two hundred and fifty-six patients diagnosed with AIH were enrolled. A person-year calculation was carried out for AIH patients, and the numbers of expected events were clarified using data from "The Monitoring of Cancer Incidence in Japan Project" in order to examine the standard incident rate (SIR) of each type of malignancy. Biochemical data regarding carcinogenesis and its background factors were also examined.

RESULTS

Twenty-seven patients (10.5%) developed malignancies; 11 (4.3%) with hepatobiliary cancer and 16 (6.3%) with extrahepatic malignancies. The overall SIR for malignancies in AIH was significantly high at 2.04 (95% confidence interval [CI], 1.34-2.96), and was high among female patients at 2.49 (95% CI, 1.60-3.71). The SIR for hepatobiliary cancer was 14.14 (95% CI, 7.05-25.30), and was markedly high for female patients at 21.83 (95% CI, 10.45-40.16). The SIR for oral/pharyngeal cancer was significantly high for female patients at 14.61 (95% CI, 1.64-52.77). The risk factors for hepatobiliary cancer at the diagnosis of AIH were low levels of alanine aminotransferase (P = 0.0226), low platelet counts (P < 0.0001), and cirrhosis (P = 0.0004). The risk factor for extrahepatic malignancy was relapse of AIH (P = 0.0485).

CONCLUSION

The risk of malignancies was generally high among AIH patients. Those with the risk factors of malignancies should be carefully followed up.

Association between hepatitis C infection in Thai patients with oral lichen planus: A case-control study

AIM

The aim of the present study was to investigate the prevalence of hepatitis C virus (HCV) infection and evaluate liver enzyme levels in patients from upper northern Thailand with oral lichen planus (OLP).

METHODS

A case-control study of 101 patients with OLP and 101 patients without OLP was conducted. Peripheral blood was taken from each patient and screened for anti-HCV antibody using immunochromatography. Positive samples were further confirmed using chemiluminescent microparticle immunoassay (CMIA) and reverse transcription-polymerase chain reaction. In addition, liver enzyme levels, alanine transaminase, aspartate transaminase, and alkaline phosphatase were evaluated using spectrophotometry.

RESULTS

Immunochromatography and CMIA revealed that nine patients with OLP (8.9%) were positive for anti-HCV antibodies, whereas only one patient without OLP was HCV positive (odds ratio = 9.78). All patients who were HCV positive had significantly higher liver enzyme levels than patients who were HCV negative.

CONCLUSIONS

The results of the present study indicated that OLP in certain patients was significantly associated with HCV. This could warrant screening for HCV-infected patients with OLP in Thailand.

Malignant transformation of oral lichen planus and oral lichenoid lesions: A meta-analysis of 20095 patient data

OBJECTIVES

For over a century, a heated debate existed over the possibility of malignant transformation of oral lichen planus (OLP). We performed this meta-analysis to evaluate the malignant potential of OLP and oral lichenoid lesions (OLL) and investigate the possible risk factors for OLP malignant transformation into oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

We searched Medline, Scopus, and Web of Knowledge for relevant observational studies. Data on OLP malignant transformation were calculated as a pooled proportion (PP), using the Der-Simonian Liard method. We performed subgroup analyses by OLP diagnostic criteria, site, and clinical type, using Open Meta[Analyst] software. Data on possible risk factors for malignant transformation were pooled as odds ratios (ORs), using Comprehensive Meta-Analysis software.

RESULTS

Pooling data for OLP malignant transformation from 57 studies (19,676 patients) resulted in an overall PP of 1.1% [95% CI: 0.9%, 1.4%], while pooling data from 14 recent studies that used the World Health Organization-2003 diagnostic criteria resulted in an overall-PP of 0.9% [95% CI: 0.5%, 1.3%]. The risk of malignant transformation was higher (PP=2.5%, 95% CI [1%, 4%]) in OLL patients (419 patients). A significant increase of malignant transformation risk was noted among smokers (OR=2, 95% CI [1.25, 3.22]), alcoholics (OR=3.52, 95% CI [1.54, 8.03]), and HCV-infected patients (OR=5, 95% CI [1.56, 16.07]), compared to patients without these risk factors.

CONCLUSION

A small subset of OLP patients (1.1%) develop OSCC; therefore, regular follow-up for these patients is recommended. A higher incidence of malignant transformation was found among smokers, alcoholics, and HCV-infected patients; however, these associations should be further investigated.

Hepatitis C virus as a systemic disease: reaching beyond the liver

Chronic hepatitis C (CHC) is associated with multiple extrahepatic manifestations that may impact infected patients. The mechanisms through which these develop include those which are immunological, in which the chronic persistence of virus leads to the circulation of immune complexes (mixed cryoglobulinemia) and other autoimmune phenomena, and those which are virological and related to the extrahepatic tropism of the virus to other tissues. It is estimated that 40-74 % of patients with CHC may develop at least one extrahepatic manifestation during the course of the disease. Extrahepatic syndromes may represent the first signal of hepatitis C infection in some patients. CHC is associated with a four-fold increased risk of insulin resistance and type 2 diabetes mellitus; with cardiovascular disease in 17-37 % of patients; and with increased risk for cerebrovascular deaths, with a biological gradient of cerebrovascular mortality correlating with an increasing serum viral load. CHC is also associated with lymphoproliferative disorders, particularly non-Hodgkin B-cell lymphoma. The kidney is involved in 35-60 % of patients with CHC-associated mixed cryoglobulinemia. The prevalent type of glomerulonephritis associated with mixed cryoglobulinemia is membranoproliferative glomerulonephritis. In 30 % of cases, renal involvement begins with a nephritis syndrome and acute renal failure, while in 55 % there is only mild hematuria, microalbuminuria, proteinuria and renal insufficiency. CHC is also associated with cognitive impairment, especially in memory and concentration. Thus, extrahepatic CHC manifestations involve multiple organ systems outside the liver linked to a variety of comorbidities which may lead to significantly increased mortality from non-liver-related events.

Increased incidence of cancer and cancer-related mortality among persons with chronic hepatitis C infection, 2006-2010

BACKGROUND & AIMS

Persons chronically infected with the hepatitis C virus (HCV) may be at higher risk for developing and dying from non-liver cancers than the general population.

METHODS

12,126 chronic HCV-infected persons in the Chronic Hepatitis Cohort Study (CHeCS) contributed 39,984 person-years of follow-up from 2006 to 2010 and were compared to 133,795,010 records from 13 Surveillance, Epidemiology and End Results Program (SEER) cancer registries, and approximately 12 million U.S. death certificates from Multiple Cause of Death (MCOD) data. Measurements included standardized rate ratios (SRR) and relative risk (RR).

RESULTS

The incidence of the following cancers was significantly higher among patients with chronic HCV infection: liver (SRR, 48.6 [95% CI, 44.4-52.7]), pancreas (2.5 [1.7-3.2]), rectum (2.1 [1.3-2.8]), kidney (1.7 [1.1-2.2]), non-Hodgkin lymphoma (NHL) (1.6 [1.2-2.1]), and lung (1.6 [1.3-1.9]). Age-adjusted mortality was significantly higher among patients with: liver (RR, 29.6 [95% CI, 29.1-30.1]), oral (5.2 [5.1-5.4]), rectum (2.6 [2.5-2.7]), NHL (2.3 [2.2-2.31]), and pancreatic (1.63 [1.6-1.7]) cancers. The mean ages of cancer diagnosis and cancer-related death were significantly younger among CHeCS HCV cohort patients compared to the general population for many cancers.

CONCLUSIONS

Incidence and mortality of many types of non-liver cancers were higher, and age at diagnosis and death younger, in patients with chronic HCV infection compared to the general population.

Oral manifestations of hepatitis C virus infection

Extrahepatic manifestations (EHMs) of hepatitis C virus (HCV) infection can affect a variety of organ systems with significant morbidity and mortality. Some of the most frequently reported EHM of HCV infection, involve the oral region predominantly or exclusively. Oral lichen planus (OLP) is a chronic inflammatory condition that is potentially malignant and represents cell-mediated reaction to a variety of extrinsic antigens, altered self-antigens, or super antigens. Robust epidemiological evidence support the link between OLP and HCV. As the virus may replicate in the oral mucosa and attract HCV-specific T lymphocytes, HCV may be implicated in OLP pathogenesis. Sjögren syndrome (SjS) is an autoimmune exocrinopathy, characterized by dryness of the mouth and eyes and a multitude of other systemic signs and symptoms. SjS patients have also an increased risk of non-Hodgkin lymphoma. Patients with chronic hepatitis C do frequently have histological signs of Sjögren-like sialadenitis with mild or even absent clinical symptoms. However, it is still unclear if HCV may cause a disease mimicking SjS or it is directly responsible for the development of SjS in a specific subset of patients. Oral squamous cell carcinoma is the most common oral malignant tumour and at least in some part of the world could be linked to HCV.

Hepatitis C virus: a silent killer relevant to dentistry

Around 25 years ago, hepatitis C virus (HCV) was identified, and following intense research and tremendous advancements, the infection is now potentially curable and even complete viral eradication is possible. It is also evident that HCV can be involved in some oral disorders, but more research is clearly warranted on oral health of HCV-infected patients. Given the global estimates on HCV epidemic and its likely huge economic impact, primary prevention and secondary prevention are worldwide priorities. However, investments are still insufficient to achieve these goals.

A rare presentation of multiple primary squamous cell carcinoma of the tongue in a patient with recurrent hepatitis C infection

Hepatitis C virus (HCV) infection has been implicated as a risk factor for development of oral squamous cell carcinoma (SCC). Multiple primary sites of oral SCC associated with HCV infection occurs infrequently. This case report describes a rare presentation of multiple primary SCCs of the tongue in a patient with recurrent HCV cirrhosis status post liver transplant that required interdisciplinary medical and surgical management. It is important for oral health care providers to understand the local and systemic implications of HCV infection and perform routine clinical examinations to monitor for development of oral lesions and associated complications.

Evidences suggesting involvement of viruses in oral squamous cell carcinoma

Oral cancer is one of the most common cancers and it constitutes a major health problem particularly in developing countries. Oral squamous cell carcinoma (OSCC) represents the most frequent of all oral neoplasms. Several risk factors have been well characterized to be associated with OSCC with substantial evidences. The etiology of OSCC is complex and involves many factors. The most clearly defined potential factors are smoking and alcohol, which substantially increase the risk of OSCC. However, despite this clear association, a substantial proportion of patients develop OSCC without exposure to them, emphasizing the role of other risk factors such as genetic susceptibility and oncogenic viruses. Some viruses are strongly associated with OSCC while the association of others is less frequent and may depend on cofactors for their carcinogenic effects. Therefore, the exact role of viruses must be evaluated with care in order to improve the diagnosis and treatment of OSCC. Although a viral association within a subset of OSCC has been shown, the molecular and histopathological characteristics of these tumors have yet to be clearly defined.

Positive association between hepatitis C infection and oral cavity cancer: a nationwide population-based cohort study in Taiwan

OBJECTIVES

The association between viral hepatitis (B and C) and oral cavity cancer has been widely debated. This nationwide, population-based cohort study assessed the subsequent risk of oral cavity cancer among patients with chronic viral hepatitis infection.

MATERIALS AND METHODS

Data were retrieved from insurance claims data of 1,000,000 randomly sampled individuals covered under the Taiwan National Health Insurance system. We identified a total of 21,199 adults with chronic viral hepatitis infection (12,369 with HBV alone, 5,311 with HCV alone, and 3,519 with HBV/HCV dual infections) from 2000-2005. Comparison group comprised 84,796 sex- and age-matched subjects without viral hepatitis during the same study period. Incidence and risk of subsequent oral cavity cancer were measured until 2008.

RESULTS

The incidence of oral cavity cancers was 2.28-fold higher among patients with HCV alone than non-viral hepatitis group (6.15 versus 2.69 per 10,000 person-years). After adjusting for sociodemographic covariates, HCV alone was significantly associated with an increased risk for oral cavity cancer (hazard ratio (HR) = 1.90, 95% confidence interval (CI) = 1.20-3.02). This positive association was highest among individuals in the 40-49-year age group (HR = 2.57, 95% CI = 1.21-5.46). However, there were no significant associations between HBV alone or HBV/HCV dual infections and risk for oral cavity cancer.

CONCLUSION

Our data suggest that HCV but not HBV infection is a risk factor for oral cavity cancer. In addition, subjects with HCV infection tend to be at early onset risk for oral cavity cancer. This finding needs to be replicated in further studies.

Oral verrucous carcinoma arising from lichen planus and esophageal squamous cell carcinoma in a patient with hepatitis C virus-related liver cirrhosis-hyperinsulinemia and malignant transformation: A case report

Oral lichen planus (OLP) is a potentially malignant disorder associated with an increased risk of oral cancer. In Japan, the association of OLP with hepatitis C virus (HCV) infection is well documented. In the present study, a case of oral verrucous carcinoma arising from OLP coexisting vulvo-vaginal-gingival syndrome and esophageal squamous cell carcinoma (SCC) in a patient with HCV-related liver cirrhosis is reported. A 71-year old, non-smoking Japanese woman presented with lesions of OLP affecting the bilateral buccal mucosa, tongue, gingival, palate, oral floor and lower lip. Ten years later, an exophytic mass developed in the mandibular alveolar mucosa, the right buccal mucosa and the right lower lip. Pathological diagnosis confirmed the presence of verrucous carcinoma. However, she developed esophageal rather than oral cancer. The oral cancer was resected surgically three times and the patients underwent radiotherapy. The esophageal cancer was removed by endoscopic submucosal dissection. The risk of carcinogenesis increased as hyperinsulinemia continued. The results suggested that it is necessary to monitor for malignant changes in patients with OLP lesions and HCV infection. In addition, treatment requires the cooperation of various medical specialists, as well as an oral surgeon.

Hepatitis C virus in patients with squamous cell carcinoma of the head and neck in Iran: is there any relation?

Recently, some studies have noticed a large number of patients with squamous cell carcinoma of the head and neck (SCCHN), who are infected with hepatitis C virus (HCV). The aim of this study is to determine the prevalence of HCV in these patients in our population. Patients with SCCHN in four tertiary centers in different regions of Iran were checked for HCV. The prevalence of HCV in 107 patients diagnosed with head and neck squamous cell carcinoma was 0.9%, which has no significant difference with its prevalence in normal population. It seems that HCV at least in Iran could not be considered as a risk factor for SCCHN.

Involvement of viral factors with head and neck cancers

The incidence of head and neck cancer remains high and is associated with many deaths in both Western and Asian countries. Common risk factors in head and neck carcinoma are smoking and alcohol abuse, however, in an increasing proportion of cases, no significant smoking or drinking history has been reported. The infectious nature of oncogenic viruses sets them apart from other carcinogenic agents. As such, a thorough study of both the pathogenesis of viral infection and the host response is crucial to a full understanding of the resulting cancers. Such an understanding, in turn, has increased our knowledge of cellular pathways involved in growth and differentiation and neoplasia as a whole. Even though human oncogenic viruses belong to different virus families and utilize diverse strategies to contribute to cancer development, they share many common features. Viruses linked to cancers in humans are the human papilloma viruses, Epstein-Barr virus, hepatitis C virus and human herpesvirus-8. The potential role and involvement of these viruses in head and neck cancers along with brief description of vaccine development is provided.

Oral diseases associated with hepatitis C virus infection. Part 2: lichen planus and other diseases

Some of the most frequent extrahepatic manifestations of hepatitis C virus (HCV) infection involve the oral region predominantly or exclusively. Part 2 of this review discusses the current evidences regarding the association of lichen planus (LP) and other diseases frequently involving the oral cavity with HCV. Epidemiological data suggest that LP may be significantly associated with HCV infections especially in southern Europe and Japan but not in northern Europe. These geographical differences are possibly influenced by immunogenetic factors, the duration of the HCV infection and the design of the published studies. Because of the fact that most of the studies published are retrospective, it is impossible to establish whether the HCV exposure occurred earlier to or after the onset of disease and more prospective studies are clearly warranted. As the virus may replicate in the skin and oral mucosa and HCV-specific T lymphocytes can be found in the oral mucosa of patients with chronic hepatitis C and LP, HCV may be implicated in the pathogenesis of LP. However, little attention has been paid to the variable effect of therapy with interferon-alpha (IFN-alpha), with or without ribavirin for LP. Conversely, it is unlikely that other oral diseases such as oral carcinoma, pemphigus and Behcet disease are triggered by HCV.

Advances in the biology of oral cancer

The incidence of oral cancer remains high and is associated with many deaths in both Western and Asian countries. Several risk factors for the development of oral cancer are now well known, including smoking, drinking and consumption of smokeless tobacco products. Genetic predisposition to oral cancer has been found in certain cases but its components are not yet entirely clear. In accordance with the multi-step theory of carcinogenesis, the natural history of oral cancer seems to gradually evolve through transitional precursor lesions from normal epithelium to a full-blown metastatic phenotype. A number of genomic lesions accompany this transformation and a wealth of related results has appeared in recent literature and is being summarized here. Furthermore, several key genes have been implicated, especially well-known tumor suppressors like the cyclin-dependent kinase inhibitors, TP53 and RB1 and oncogenes like the cyclin family, EGFR and ras. Viral infections, particularly with oncogenic HPV subtypes and EBV, can have a tumorigenic effect on oral epithelia and their role is discussed, along with potential therapeutic interventions. A brief explanatory theoretical model of oral carcinogenesis is provided and potential avenues for further research are highlighted.

No evidence of hepatitis C virus infection in Serbian patients with oral leukoplakia

BACKGROUND

A review of the literature reveals controversy regarding the relationship between hepatitis C virus (HCV) infection and oral leukoplakia (OL). The aim of this study was to determine the frequency of HCV antibodies in patients with OL and control subjects resident in Serbia.

METHODS

In this cross-sectional study 73 consecutive patients with histologically proven OL and 90 control subjects, whose age and gender were matched, were examined for the presence of serological evidence of chronic hepatic disease, hepatitis B surface antigen (HBsAg) and anti-HCV seropositivity.

RESULTS

None of the patients with OL or control subjects had antibodies to HCV or HBsAg. All patients with OL and control subjects had normal liver function.

CONCLUSION

The present data indicate that patients with OL resident in Serbia do not have evidence of HCV or HBV infection.

Hepatitis C virus in elderly cancer patients

BACKGROUND

There are few studies about the relationship between HCV and the development of other tumors. We consider the prevalence of HCV infection in elderly cancer patients who have tumors different from that in hepatocellular carcinoma and non-Hodgkin's lymphoma.

METHODS

We evaluated the prevalence of HCV infection in 236 elderly cancer patients in comparison with 300 elderly volunteers. Cancer patients presented a variety of tumors other than hepatocarcinoma and lymphoma, namely, colorectal (n=66), breast (n=44), bladder (n=40), prostate (n=30), lung (n=22), kidney (n=15), pancreatic (n=6), thyroid (n=5), cervical (n=4), melanoma (n=3) and vaginal (n=1).

RESULTS

Among the 236 elderly cancer patients, 87 were positive for HCV antibodies (36%) and, among the 300 elderly patients, 32 were positive (10%). A comparison between the two groups revealed a statistically significant difference (p<0.001) between patients with kidney cancer, bladder cancer or prostate cancer, and the control group.

CONCLUSIONS

The high anti-HCV prevalence in elderly cancer patients may be due to several mechanisms. These patients are more prone to acquire an HCV infection because of their frequent hospitalizations and the immunological changes in patients with tumors may lower their threshold for HCV infection.

Hepatitis C virus and lichen planus

Hepatitis C virus (HCV) is an important factor in the development of chronic liver disease and hepatocellular carcinoma. In recent years it has become known that HCV induces various extrahepatic manifestations including mixed cryoglobulinemia, membranoproliferative glomerulonephritis, Sjögren's syndrome, autoimmune thyroiditis, malignant lymphoma, porphyria cutanea tarda and lichen planus. Although the mechanisms of extrahepatic manifestations remain unclear, it is known that interferon (IFN) therapy and coadministration of IFN with ribavirin are effective in promoting the disappearance or alleviation of such extrahepatic lesions, which have tended to be overlooked. The present review focuses on lichen planus, one of the major extrahepatic manifestations.

Risk of oral squamous cell carcinoma in 402 patients with oral lichen planus: a follow-up study in an Italian population

The most important complication of oral lichen planus (OLP) is the development of oral squamous cell carcinoma (OSCC) but this is a very controversial matter. The aim of the study was to estimate in a Northern Italian cohort of OLP patients the risk for OSCC. Four hundred and two patients with histologically confirmed OLP diagnosed from January 1988 to July 1999, were followed-up to the end of February 2001. The standardized incidence ratio (SIR) of OSCC was calculated for the entire cohort and specific for gender, type of OLP, therapy for OLP and hepatitis C virus (HCV) infection. The relative risk (RR) of OSCC according to HCV infection was also estimated in the cohort. During the follow-up period, two men (1.3%) and seven women (2.9%) developed an OSCC. The SIR was 44.9 (95% CI: 20.5-85.2), being higher among women, but statistically significant in both genders. The RR of OSCC for patients with HCV as compared with those without HCV infection was 3.16 (0.8-12.5). Patients with OLP had a significantly increased risk of OSCC, irrespective of the clinical type of OLP and therapy. HCV infection apparently increased the risk for OSCC although this result could reflect the role of confounders, such as liver cirrhosis.

Oral diseases possibly associated with hepatitis C virus

Morbidity associated with hepatitis C virus (HCV) infection can involve a variety of extrahepatic conditions, including lichen planus (LP) and sialadenitis, predominantly or exclusively involving the oral region, conditions which have been largely neglected in reviews. The literature suggests that HCV-infected patients may frequently have Sjögren-like sialadenitis with mild clinical symptoms, whereas oral LP may be significantly associated with HCV infections in Southern Europe and Japan but not in Northern Europe. These geographical differences could be related to immunogenetic factors such as the HLA-DR6 allele, significantly expressed in Italian patients with OLP and HCV. Analysis of experimental data suggests that HCV could be involved in the pathogenesis of both these diseases. Moreover, parotid lymphoma may arise in patients with sialadenitis, mainly with type II cryoglobulinemia. Little attention has been paid to oral health needs in HCV-infected patients and the variable effect of interferon-alpha therapy on oral tissues. Further research is needed, because of the potentially great influence of oral diseases possibly linked to HCV on the quality of life of millions of patients.

Lack of association between hepatitis C virus and oral epithelial dysplasia in British patients

Oral lichen planus may be a premalignant condition. An association between hepatitis C virus (HCV) infection and oral lichen planus has been described in Southern European and Japanese patients, and recently an association between HCV and oral squamous cell carcinoma was suggested from a study of Japanese patients. The present study investigated the frequency of chronic liver disease and HCV infection in UK patients with oral epithelial dysplasia (OED), a known premalignant disorder. Subjects included 75 patients with histologically proven OED and 110 healthy controls. Liver function and IgG antibodies to HCV were examined serologically. No patient with OED or control subject had serological evidence of hepatic disease, and anti-HCV antibodies were detected in only two (2.6%) of the 75 patients with OED, none of the controls being HCV seropositive. It is concluded that in the UK there is no association between HCV infection and OED.

Prevalence of hepatitis virus infection in association with oral diseases requiring surgery

OBJECTIVE

We evaluated the prevalence of hepatitis virus infection in a large population of patients in terms of diseases requiring oral surgery.

DESIGN

Retrospective case survey.

SUBJECTS AND METHODS

Prevalence of hepatitis B and C virus (HBV, HCV) infection were compared between oral diseases such as inflammation, cysts, cancer, trauma, benign tumors, impacted teeth, or jaw deformity in dental inpatients (n = 5830) with adjustment for age, gender, and history of surgery.

RESULTS

Of 4402 inpatients, 94 had HB surface(s) antigen (2.1%), while 151 of 2613 were seropositive for HCV (5.8%). Prevalences of HBs antigen and HCV antibody exceeded those in the general population. HBs antigen was more prevalent in patients with benign oral tumors than in patients with impacted teeth, whether or not adjustment was made for age (odds ratios, 4.246 and 5.055 with and without age adjustment, respectively; P < 0.05). On the other hand, HCV antibody was more prevalent in patients with oral cancer than in those with impacted teeth before adjustment for age (odds ratios, 2.433; P < 0.05), but this difference was reversed with age adjustment (odds ratios, 0.443; P < 0.05).

CONCLUSION

HBs antigen was more prevalent in patients with benign oral tumors, while HCV antibody was higher in patients with oral cancer. However, this increased incidence of HCV antibody apparently was a reflection of age. HCV infection may not have an etiologically important association with oral cancer.

Infectious hepatitis C, hepatitis G, and TT virus: review and implications for dentists

In the past 10 years, hepatitis C and G viruses have been identified, and in the last two years a further parenterally transmitted agent, termed TT virus (TTV), has been discovered. These viruses have a worldwide distribution and frequently cause chronic infection. The purpose of this article was to promote an understanding of these viral agents and their relevance in dental practice. Infected patients may develop a chronic carrier state without clinical disease or may develop liver disease, and may have related oral conditions. Dental providers will see a growing number of patients with HCV/HGV and possibly TTV infection. All of these patients require appropriate infection control measures during dental treatment.

Histopathological and immunohistochemical study of oral lichen planus-associated HCV infection

Background: In recent years, it has been suggested that oral lichen planus (OLP), a chronic inflammatory keratotic lesion, is related to hepatitis C virus (HCV) infection. Therefore, we evaluated whether the presence or absence of HCV infection caused any histopathological differences in OLP tissues. Methods; The subjects consisted of 31 patients with HCV-related liver disease complicated by OLP (32 OLP lesions) and ten OLP patients without complications due to either HCV infection or liver disease (control). A histopathological evaluation was performed in these patients. In addition, immunostaining was done on nine OLP tissues infected with HCV and on six OLP tissues without HCV infection in order to evaluate lymphocyte subsets (T cells or B cells) infiltrating into topical regions with OLP. Furthermore, the severity of hepatic fibrosis and inflammation was evaluated in liver tissues obtained by liver biopsy from six patients with HCV-related liver disease to evaluate whether there were any relationships between the severity of hepatic fibrosis or inflammation and OLP tissues. Results: There were no significant differences in the histopathological characteristics specific to OLP or in the ratios of T and B cells among infiltrating lymphocytes regardless of the presence or absence of HCV infection. Moreover, there were no certain relationships between the severity of hepatic fibrosis or inflammation and the severity of lymphocytic infiltration in OLP. Conclusions: HCV infection does not appear to influence the histopathological and immunohistochemical features of OLP.

The possible association between oral lichen planus and oral squamous cell carcinoma: a clinical evaluation on 14 cases and a review of the literature

Between 1986 and 1996, 263 patients, 156 females and 107 males, affected by oral lichen planus (OLP), were followed at the Division of Oral Medicine and Pathology, University of Naples 'Federico II', Italy, and at the Institute of Dentistry and Maxillofacial Surgery, University of Bari, Italy. During this follow-up, the possible association of OLP with oral squamous cell carcinoma (SCC), together with the possible association of OLP, oral SCC and chronic HCV-hepatitis, were investigated. 14 cases (5.32%) were known to have developed oral SCC: 10 (3.8%) in an area of pre-existing OLP, 3 (1.14%) in other sites, in 1 case the diagnosis of OLP and SCC was synchronous (0.38%). 3 patients were positive for anti-HCV antibody. Many carcinomas were in areas of reticular/plaque OLP. 3 patients had multiple simultaneous sites of oral involvement (21.42%); 5 patients developed oral SCC in different sites during the follow-up period (35.71%). These data, together with a clear histological evidence of progression to carcinoma within OLP lesions, suggest the probability of some cases of at least OLP having an intrinsic property predisposing to neoplastic transformation, confirming previous studies. For these reasons, the authors think that it is necessary to follow-up the patients regularly at least annually and possibly for life for the early diagnosis of a possible neoplastic degeneration. These consideration are particularly important in the case of atrophic or erosive OLP, and plaque OLP, especially when involving the dorsum of tongue.

Hepatitis C virus infection: Review and implications for the dentist

OBJECTIVE

The purpose of this report was to review the current literature on hepatitis C virus infection, with particular attention to the aspects of interest for dental health care staff.

MATERIAL AND METHODS

The authors searched original research and review articles on specific aspects of hepatitis C virus infection, including articles on virology, epidemiology, transmission, diagnosis, natural history, extrahepatic manifestations, therapy and oral aspects of hepatitis C virus infection. The relevant material was evaluated and reviewed.

RESULTS

Hepatitis C virus is an RNA virus that is present throughout the world and has major geographic variations. The virus, transmitted mainly by means of blood contact, causes chronic hepatitis in up to 80% of cases and may give rise to hepatic cirrhosis and hepatocellular carcinoma in a significant proportion of patients. Although it is of limited efficacy, interferon alpha is currently the drug of choice in the treatment of the infection. Hepatitis C virus infection is associated with a number of extrahepatic manifestations that may include oral diseases such as lichen planus or sialadenitis. Although there are documented cases of nosocomial transmission to health care workers after percutaneous exposure, the prevalence of hepatitis C virus among dental staff members is probably similar to that in the general population.

CONCLUSION

Hepatitis C virus infection is a relatively common infection worldwide (1.4% in the US general population) that causes significant chronic hepatic disease. The dentist is thus likely to face a growing number of patients with a diagnosis of hepatitis C virus infection. For this reason it is essential for dental health care workers to be aware of the principal features of the disease and of its oral and dental implications.

Hepatitis C virus infection and lichen planus: a short review

OBJECTIVE

To review the current literature regarding the association of lichen planus (LP) and liver disease, with particular attention to the association of the oral variant of the disease with hepatitis C virus (HCV) infection.

MATERIALS AND METHODS

Available literature of the possible association of LP with systemic disorders, in particular chronic hepatic disease, has been reviewed.

RESULTS

LP is sometimes associated with infectious or autoimmune disease and/or neoplasia, however an aetiological association between LP and these disorders seems unlikely. A more consistent association exists between LP and chronic hepatic disease. The precise cause of this association is not known. However, in the last 6 years a notable association between HCV infection and LP has been observed, particularly in patients in Spain, Italy and Japan. The pathogenesis of this possible HCV-associated LP is not known, but it may involve a cell mediated response to an altered epithelial antigen.

CONCLUSION

There is now evidence to suggest a significant association between HCV infection and LP in some groups of patients.

An atypical verrucous carcinoma of the tongue arising in a patient with oral lichen planus associated with hepatitis C virus infection

Recently, a clinical relationship between oral lichen planus (OLP) and hepatitis C virus (HCV) infection has been suggested, but the role of this virus on the course of OLP is unknown. We report an unusual lingual localisation of verrucous carcinoma arising in a patient with histologically confirmed OLP and HCV infection diagnosed with second generation enzyme-linked immunosorbent assay and recombinant immunoblot assay. Serum HCV-RNA detected using nested reverse transcriptase polymerase chain reaction (RT-PCR) confirm HCV replication. No classical risk factors associated with verrucous carcinoma were present.

GB virus infection in patients with oral cancer and oral lichen planus

We studied the incidence of GBV-C infection in patients with oral cancer or oral lichen planus (OLP). Subjects included 38 patients with oral cancer and 34 patients with OLP from whom serum was collected to detect GBV-C-RNA using reverse transcription (RT) "nested" PCR. GBV-C-RNA was positive in 1 (2.6%) oral cancer patient and 3 (8.8%) OLP patients. All 4 GBV-C-positive patients were also positive both for the antibody for hepatitis C virus (anti-HCV) and HCV-RNA, indicating simultaneous infection with GBV-C and HCV. In conclusion, GBV-C infection was found in 5.5% (4/72) of oral cancer or OLP patients and all patients infected with GBV-C also had HCV infection. This suggests that GBV-C infection is unlikely to play an important role in the pathogenesis of oral cancer and OLP.