Malignant Transformation Of Oral Lichen Planus Research Articles

Malignant Transformation in Oral Lichen Planus and Lichenoid Reactions in Southern Thai Population

Objectives: This study aimed to determine the prevalence of malignant transformation (MT) and the incidence rate of oral squamous cell carcinoma (OSCC) in oral lichen planus (OLP) and oral lichenoid reaction (OLR) patients from southern Thailand. Methods: This hospital-based retrospective cohort study comprised OLP/OLR patients who were treated between January 2016 and December 2022. Data on the general characteristics, clinical manifestations and laboratory investigations were obtained from the hospital records and analyzed. Descriptive and analytical statistics were performed to assess the demographic data, clinical profiles of the patients and the prevalence and incidence rate of MT. Results: A total of 117 patients were included in the study; 103 (88%) were diagnosed with OLP, and 14 (12%) were diagnosed with OLR. The median follow-up time was 15.6 months (interquartile range; 6.1-46.0). The overall prevalence of MT in OLP/OLR was 1.71% (2/117 patients); specifically, MT in OLP was 1.94% (2/103 patients). The overall annual incidence rate of MT into OSCC was 0.0060 (95% confidence interval, 0.0015-0.0240). Conclusions: These findings suggest that OLP is a potentially malignant disorder with an MT incidence of 1.94% in the southern Thai population. OLP patients must be regularly followed-up and advised about the risk of MT.

Malignant Transformation of Oral Lichen Planus—An Umbrella Study of Systematic Reviews

Oral lichen planus (OLP) is classified as a potentially malignant disorder. Systematic reviews collating longitudinal observation studies provide evidence of the rate or proportion of malignant transformation. We conducted an umbrella study of published systematic reviews. An extensive English-language study search was carried out in several databases to identify relevant articles, providing systematic reviews on the malignant transformation of OLP. Data from eight systematic reviews published between 2014 and 2023 are presented. The reported proportions of malignant transformation ranged from 1.1% to 1.4%. A meta-analysis based on the 10 highest-quality studies yielded a higher proportion of malignant transformation (2.28%). We list some limitations found in several of these systematic reviews. Some studies reported an increased risk of malignancy in OLP lesions, demonstrating epithelial dysplasia. In view of the consistent evidence of the risk of oral malignancy, OLP patients should be monitored carefully to detect early cancer development.

Investigating the factors proposed in oral lichen planus malignant transformation: A literature review.

Lichen planus is a chronic inflammatory disease that affects about 1% of the world's population. The World Health Organization has included oral lichen planusamong potentially malignant disorders. Identification of reliable biomarkers for the diagnosis of malignant transformation may play a unique role in the development of standard screening and improvement of follow-up in patients with oral precancerous lesions. It is currently assumed that the molecular pathways controlling growth, maturation, proliferation, and apoptosis in epithelial cells may play an important role in the process of transformation into malignancy. The search was done in PubMed, Scopus, Google Scholar, Embase, and Cochrane databases from 1960 to 2022. Based on the inclusion criteria, 23 articles were included. In this review of articles, 34 different biomarkers that have been investigated in studies for the possibility of malignant transformation in OLP have been studied. Among all the risk factors related to malignant transformation, most studies have been done on the role of cytokines and tumor suppressors, in fact, the chronicity of the lesion which is the result of the reaction between the repair and the inflammatory response and the responses accompanied by the secretion of cytokines, may play a major role in the malignant transformation of OLP.

Rate of Malignant Transformation Differs Based on Diagnostic Criteria for Oral Lichenoid Conditions: A Systematic Review and Meta-Analysis of 24,277 Patients.

This systematic review and meta-analysis aims to evaluate the evidence on the malignant potential of oral lichenoid conditions (OLCs) including oral lichen planus (OLP), oral lichenoid lesions (OLL), and lichenoid mucositis dysplasia (LMD). In addition, it aims to compare the rate of malignant transformation (MT) in OLP patients diagnosed according to different diagnostic criteria, and to investigate the possible risk factors for OLP MT into OSCC. A standardized search strategy was applied across four databases (PubMed, Embase, Web of Science, and Scopus). Screening, identification and reporting followed the PRISMA framework. Data on MT were calculated as a pooled proportion (PP), subgroup analyses and possible risk factors for MT were pooled as odds ratios (ORs). Among 54 studies with 24,277 patients, the PP for OLCs MT was 1.07% (95% CI [0.82, 1.32]). The estimated MT rate for OLP, OLL and LMD was 0.94%, 1.95% and 6.31%, respectively. The PP OLP MT rate using the 2003 modified WHO criteria group was lower than that using the non-2003 criteria (0.86%; 95% CI [0.51, 1.22] versus 1.01%; 95% CI [0.67, 1.35]). A higher odds ratio of MT was observed for red OLP lesions (OR = 3.52; 95% CI [2.20, 5.64]), smokers (OR = 1.79; 95% CI [1.02, 3.03]), alcohol consumers (OR = 3.27, 95% CI [1.11, 9.64]) and those infected with HCV (OR = 2.55, 95% CI [1.58, 4.13]), compared to those without these risk factors. OLP and OLL carry a low risk of developing OSCC. MT rates differed based on diagnostic criteria. A higher odds ratio of MT was observed among red OLP lesions, smokers, alcohol consumers, and HCV-positive patients. These findings have implications for practice and policies.

Is oral lichen planus a potentially malignant disorder?: A critical appraisal; a commentary on the letter to the editor.

Is oral lichen planus a potentially malignant disorder?: A critical appraisal; a commentary on the letter to the editor.

A study of stromal collagen in oral lichen planus, carcinoma in situ, early invasive squamous cell carcinoma, and normal mucosa using picrosirius red stain

Background and Objectives: Oral lichen planus (OLP) is a chronic disease of uncertain cause commonly affecting oral cavity. Although the WHO has designated OLP as a “potentially malignant disorder,” controversies exist regarding its malignant potential. Collagen forms the principal component of stroma or extracellular matrix and its role in carcinogenesis is widely studied in other premalignancies. Although collagen at the basal complex of OLP is widely explored, studies on collagen in the connective tissue stroma are not reported to date. We aimed to observe the nature of collagen in connective tissue stroma of OLP using picrosirius red stain (PSR) under polarized microscope and compare with buccal mucosa without any pathology related to exposure to tobacco and other oral carcinogens, carcinoma in situ (Ca in situ), and early invasive squamous cell carcinoma (EISCC). Materials and Methods: Eighty samples were observed, with twenty samples in each study group. Two 4–6-μ thick sections were obtained from the archival blocks. One section was stained with hematoxylin and eosin for confirming the diagnosis, whereas PSR staining was done for the other section. Both sections were analyzed using a polarizing microscope for evaluating the polarization colors of collagen. The images captured were stored on a computer. Five nonoverlapping fields were selected from each section in all groups and the thickness of five collagen fibers from each section was measured in microns using image analysis software and the polarizing color was also noted. The values obtained were compared using Kruskal–Wallis H-test and Chi-square test. We also used Mann–Whitney U-test for intergroup comparison. Results: The mean width of thick as well as thin fibers was more in controls than Ca in situ, OLP, and EISCC in decreasing order. Mature fibers were predominant in the controls than Ca in situ, OLP, and EISCC in decreasing order. Immature fibers were predominant in EISCC, followed by OLP, Ca in situ, and controls. Comparison of collagen in OLP and Ca in situ showed no statistically significant result in terms of thickness and polarization colors confirming a similarity in the nature of collagen in these two lesions. Conclusion: The stromal collagen of OLP was comparable to Ca in situ suggesting a change in the structure and organization of collagen probably attributed to the role of inflammatory mediators. A study with bigger sample size is recommended to evaluate the role of collagen in malignant transformation of OLP.

Retrospective Study of Oral Lichen Planus and Oral Lichenoid Lesions: Clinical Profile and Malignant Transformation.

Oral lichen planus (OLP) and other oral lichenoid lesions (OLL) are reported to have the potential of malignant transformation and dysplastic changes, turning into oral squamous cell carcinoma (SCC). While the world health organization (WHO) has classified OLP as a precancerous lesion of the oral cavity, there is still much debate among researchers about its risks and malignancy potential. The present study aimed to determine malignant transformation in OLP and OLL and understand related risk factors. This retrospective study was performed on 356 patients of the Oral Medicine Department of Dental School of Kerman Medical University from 1998 to 2020. All patients' records were gathered. In addition, patients were followed up routinely. Second biopsy was taken as needed. The samples, previously taken from the patients, were re-evaluated according to WHO histopathologic criteria for diagnosing OLP, OLL, dysplasia, and SCC by an experienced pathologist and compared with first reports. Dysplastic changes were observed in 6.2% of the patients. In more than half of the patients, dysplastic changes were present right from the start and 2.20% of the patients had experienced dysplastic changes averagely within 2.05 years of the onset of lesions. Multiple logistic regression showed that the risk of dysplasia increases with aging (p= 0.013), smoking (p= 0.0001), and thyroid disorders (p= 0.008). Given the rather high prevalence of oral lichen planus and lichenoid lesions, further research appears to be needed to determine the etiology of these lesions, malignant transformations, and the factors affecting this probability. Considering the findings, it is imperative to meticulously record the information of all patients with oral lichen planus and lichenoid lesions in the initial examinations as well as close follow-ups and employ diagnostic tools such as toluidine blue staining or even repeat biopsy when necessary.

Expression of human papillomavirus 16 and 18 DNA in oral lichen planus using polymerase chain reaction.

Oral lichen planus (OLP) is a chronic inflammatory disease with cell-mediated immune dysregulation. The aetiology of OLP has been studied extensively for decades. Viruses like Hepatitis C Virus (HCV), human papillomavirus (HPV), herpes simplex virus (HSV), and stress have been hypothesized to play a role in the pathogenesis and malignant transformation of OLP. HPV has been proved to be an etiological agent in oropharyngeal cancers and non-tobacco-associated leukoplakia. The role of human papillomavirus in the pathogenesis of OLP has to be studied extensively. This study aims to detect the presence of HPV 16 and HPV 18 DNA in the biopsy samples of OLP and also to determine the role played by the virus in the pathogenesis and malignant transformation of OLP. Biopsy samples comprising 30 OLP tissues were collected. The DNA was extracted by the cetyltrimethylammonium bromide method. Polymerase chain reaction was performed by using general primers to amplify the HPV E6 gene. Twelve out of 30 (40%) OLP cases were positive for HPV DNA. A significant relation was found between HPV, site (buccal mucosa) and the type (reticular) of the lesion (P = 0.007). However, the difference between the percentage of HPV positive males and females was statistically insignificant (P = 0.852). This study confirmed the presence of high-risk HPV 16 and HPV 18 DNA in OLP. The study showed a significantly higher expression of HPV in erosive OLP when compared to reticular OLP, suggesting a possible role of HPV in the malignant transformation of OLP.

Molecular detection of human papillomavirus DNA in dysplastic and non-dysplastic oral lichen planus patients

Introduction: Oral Lichen Planus (OLP) is a chronic inflammatory disease of cell-mediated dysregulation characterized by relapses and remissions. The aetiology of OLP has been extensively studied for decades. The pathogenesis is unclear with a debatable malignant transformation. The pathogenesis and malignant transformation of OLP may be affected by viruses such as Hepatitis C Virus (HCV), Human Papillomavirus (HPV), Herpes Simplex Virus (HSV), and stress. HPV has been proved to be an etiological agent in oropharyngeal cancers and non-tobacco-associated leukoplakia. The role of human papillomavirus in the pathogenesis of OLP and its malignant transformation has to be studied extensively. Aim: This study aims to detect the presence of HPV DNA in the biopsy samples of dysplastic and non-dysplastic OLP and thus determine the role the virus played in the malignant transformation of OLP. Materials and Methods: Biopsy samples comprising 250 OLP tissues were collected. The DNA was extracted from the fixed tissue by using the Cetyltrimethylammonium bromide (CTAB) method. Polymerase Chain Reaction (PCR) was performed using primers to amplify the HPV E6 gene. Results: Hundred and three out of 250 (41.2%) OLP cases were positive for HPV DNA.

What is the malignant transformation potential of oral lichen planus?

Data sources In this systematic review and meta-analysis, Medline, Scopus and Web of Science databases were searched using Medical Subject Headings (MeSH) to identify studies assessing the risk of malignant transformation in oral lichen planus (OLP).Study selection Observational studies published in English between 2003-2020 were independently assessed for inclusion by two blinded investigators.Data extraction and synthesis Data were extracted independently by two investigators followed by discussion to reach consensus. This included: study design and patient characteristics; length of follow-up; risk of bias; method of OLP diagnosis; oral squamous cell carcinoma (OSCC) risk factors; rate of malignant transformation; and individual characteristics of malignant transformation cases. Cases of malignant transformation in the included studies were only included in meta-analysis if: 1) OLP diagnosis met current diagnostic criteria; 2) OSCC developed in the same site as previously diagnosed OLP after at least six months' follow-up; 3) the patient had no history of systemic immunosuppressive therapy, head and neck malignancy, or organ transplantation. Risk of bias was assessed using the modified Newcastle-Ottawa scale, and meta-analysis was conducted to estimate overall risk of OLP malignant transformation using the DerSimonian and Laird method. Pooled univariate odds ratios (OR) for malignant transformation were calculated based on gender, smoking status, alcohol consumption, hepatitis C infection and OLP subtype.Results In total, 593 studies were identified after removal of duplicates and 33 studies were included for data extraction. The included sample comprised 12,838 patients with OLP, and 151 malignant transformation cases were reported in the included studies. The authors excluded 56 malignant transformation cases from the meta-analysis, most commonly because of the absence of pathological OLP diagnosis. Among included malignant transformation cases, the mean (SD) age was 58.1 (12.4) years, and 64% of the sample was female. Random-effects meta-analysis estimated an OLP malignant transformation rate of 0.2% (95%CI: 0.1-0.3%). Heterogeneity was low (I2 = 28.74%, p = 0.065). Malignant transformation was significantly higher among smokers (OR = 4.62, p = 0.001), alcohol consumers (OR = 3.22, p = 0.05), those with hepatitis C (OR = 3.77, p = 0.03) and atrophic or erosive OLP subtypes (OR = 2.70, p = 0.03). Gender was not associated with increased risk of malignant transformation.Conclusions The malignant transformation rate of OLP is likely to be lower than previously reported, possibly as a result of variable diagnostic criteria. Whilst encouraging, clinical vigilance remains necessary, as OLP does carry a small risk of malignant transformation. Smoking, alcohol use, hepatitis C infection and erosive or atrophic subtypes appear to have a greater rate of malignant transformation.

A Survey of Brazilian Patients with Oral Lichen Planus Showing No Evidence of Malignancy.

Objectives There is conflicting evidence as to whether oral lichen planus (OLP) can undergo malignant transformation into oral squamous cell carcinoma (OSCC). This study aimed to address this issue by analyzing a sample of Brazilian patients with either OLP or OSCC. Patients and Methods. This study was conducted in São Paulo, the world's fourth-largest city by population. Two groups of patients were analyzed. The OLP group consisted of 370 patients, while the OSCC group consisted of 154 patients. The OLP patients were followed up for up to 21 years to monitor clinical benefits from the management or changes in the lesion morphology; conversely, patients with OSCC were examined only twice for diagnostic purposes and referred to a specialized center. Data concerning systemic diseases, use of medications, type of oral lesions, and health-risk behaviors were recorded for patients in both groups. Results None of the patients with OLP developed OSCC at the lesion site. Only one female patient with erosive OLP developed OSCC in the normal, lesion-free oral mucosa. None of the OSCC patients had concomitant OLP lesions; however, a higher percentage of OSCC cases (17.5%) showed white plaques (most likely oral leukoplakia) as a precursor lesion. Conclusion The findings strongly suggest that malignant transformation of OLP is virtually nonexistent in the Brazilian population.

Cathepsin-B and caveolin-1 gene expressions in oral lichen planus and oral squamous cell carcinoma.

Given the importance of the role of cellular changes in the prognosis and diagnosis of malignancies of the head and neck, we examined in this study the gene expressions of cathepsin-B (Cat-B) and caveolin-1 (Cav-1) which are in cell membranes structures involved in carcinogenesis, in oral squamous cell carcinoma (OSCC) and oral lichen planus (OLP) and compared them to controls. We also investigated their relationship to clinicopathological indices. In this case-control study, 29 paraffin blocks of OLP patients were compared to 29 paraffin blocks of OSCC samples as well as 28 paraffin blocks of normal oral tissue. Real-time quantitative PCR was performed to determine gene expressions and results were analyzed for their relationship to clinical data using chi-square, Kruskal-Wallis and Mann-Whitney tests. The mean age of OSCC and OLP patients were 59.24 ± 15.04 and 48.79 ± 14.17years, respectively. The Cat-B and Cav-1 expressions were significantly higher in OSCC and OLP samples compared to control (p < 0.001). The highest expression was found in OSCC samples. The difference between OLP and control samples for Cat-B and Cav-1 expression was significant. There was no association between the gene expression and age, gender, duration of disease, Thongprasom score, smoking and cutaneous lichen planus. However, the expressions were related to the grade and stage of OSCC samples (P = 0.01, P = 0.02). The gene expressions of Cat-B and Cav-1 in OSCC were associated with the stage and grade of lesions. Therefore, they appear to be useful in predicting the biological behavior of OSCC and malignant transformation of OLP, although this process is multi factorial and more investigations are needed.

Risk co-factors inducing malignant transformation of oral lichen planus: A literature review of clinical studies

Oral lichen planus (OLP) is an autoimmune chronic inflammatory disease. The potential risk of malignant transformation in OLP remains controversial. The aim of the present study was to review original clinical studies published in indexed databases, which assessed the potential risk cofactors which were implicated in the malignant transformation of oral lichen planus. We focused our search to include most of the studies that reported malignant transformation of oral lichen planus using different combinations of the following key indexing terms: oral lichen planus, malignant transformation, smoking, alcohol, chronic inflammation, candida, human papillomavirus (HPV), hepatitis C virus (HCV) and immunosuppression. The animal studies were excluded from our study. Despite a dearth of studies on this topic we have identified consumption of tobacco and/or alcohol, the presence of erosive and/or atrophic areas, infection with candida, HCV, HPV, and immunosuppression as significant cofactors. Patients with OLP with these risk co-factors are at risk of malignant transformation should, therefore be followed up for an extensive period or even for life.

Salivary KLK5 and uPA are potential biomarkers for malignant transformation of OLK and OLP.

Oral squamous cell carcinoma (OSCC) usually originates from oral potentially malignant disorders (OPMD), such as oral leukoplakia (OLK) and oral lichen planus (OLP). Identifying biomarkers for the early diagnosis and evaluation of malignant transformation in OPMD could improve the survival rate of OSCC patients. The present study aimed to screen for potential salivary biomarkers for evaluating the malignant transformation of OPMD. Salivary proteases from OLK and OSCC patients or healthy donors and proteases in cultural medium from DOK and Cal-27 cells were detected with a human protease array kit. The concentrations of the salivary Kallikrein 5 (KLK5) and urokinase-type plasminogen activator (uPA) proteases were measured by ELISA. Receiver operating characteristics (ROC) to determine the potential value of these proteases in clinical diagnosis were calculated using SPSS software. Immunohistochemistry was used to detect the KLK5 and uPA expression in the oral organizations. The salivary protease spectrum was different among patients with OLK and OSCC and healthy donors. KLK5 and uPA levels in saliva tended to increase as the disease progressed (healthy < OPMD [OLK and OLP] < OSCC). ROC curves showed the optimum diagnostic cutoffs for KLK5 as a biomarker for OLK, OLP, and OSCC were 5.97, 6.03, and 9.45pg/mL, respectively, while the cutoffs for uPA were 17.19, 17.26, and 20.96pg/mL. Their combined analysis showed a higher sensitivity for the differential diagnosis of disease. Furthermore, higher levels of KLK5 and uPA were observed in OSCC tissues than in OLK and OLP. Salivary KLK5 and uPA are potential biomarkers for evaluating OLK and OLP malignant transformation and early diagnosis of OSCC.

Role of Human Papilloma Virus in Malignant Transformation of Oral Lichen Planus: A Systematic Review.

Lichen planus (LP) is a chronic inflammatory mucocutaneous disease. The disease has a cell-mediated immune reaction which is precipitated by a specific trigger which turns the self-peptides antigenic. The role of human papillomavirus (HPV) in the malignant transformation of oral LP (OLP) has always been debated. Establishing a definitive part played by HPV in the malignant transformation of OLP, would possibly provide screening for the viruses, HPV vaccination, and antiviral therapy along with conventional treatment in LP which could improve prognosis. This systematic review is to assess the role of HPV in the malignant transformation of OLP. We performed a systematic search of PubMed, MEDLINE, and Google. The information was extracted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All full-text papers that assessed the association of HPV in malignant transformation of OLP were considered eligible. The outcome parameter included the malignant transformation of OLP. We found a total of 19 studies from which five were found suitable for the review. Results from this systematic review showed HPV is associated with OLP. There is an increased prevalence of HPV in the erosive-atrophic (EA) variant of OLP compared to non-EA variant. There seems to be no strong evidence to prove the association between HPV and malignant transformation of OLP. Taking up the oncogenic potential of high-risk types and OLP as a potentially malignant disorder, more number of studies need to be performed on the dysplastic subtype of OLP and in those OLP lesions that progress to oral squamous cell carcinomas.

Malignant transformation of oral lichen planus and related genetic factors

Oral lichen planus (OLP) is a chronic inflammatory disease observed in approximately 0.5–2.2% of the population, and it is recognized as a premalignant lesion that can progress into oral squamous cell carcinoma (OSCC). The rate of malignant transformation is approximately 1.09–2.3%, and the risk factors for malignant transformation are age, female, erosive type, and tongue site location. Malignant transformation of OLP is likely related to the low frequency of apoptotic phenomena. Therefore, apoptosis-related genetic factors, like p53, BCL-2, and BAX are reviewed. Increased p53 expression and altered expression of BCL-2 and BAX were observed in OLP patients, and the malignant transformation rate in these patients was relatively higher. The involvement of microRNA (miRNA) in the malignant transformation of OLP is also reviewed. Because autophagy is involved in cell survival and death through the regulation of various cellular processes, autophagy-related genetic factors may function as factors for malignant transformation. In OLP, decreased levels of ATG9B mRNA and a higher expression of IGF1 were observed, suggesting a reduction in cell death and autophagic response. Activated IGF1-PI3K/AKT/mTor cascade may play an important role in a signaling pathway related to the malignant transformation of OLP to OSCC. Recent research has shown that miRNAs, such as miR-199 and miR-122, activate the cascade, increasing the prosurvival and proproliferative signals.

Oral lichen planus has a very low malignant transformation rate: A systematic review and meta‐analysis using strict diagnostic and inclusion criteria

The malignant transformation (MT) potential of oral lichen planus (OLP) has sparked heated debates for almost a century, despite the fact that global figures of OLP prevalence and oral cancer incidence do not support an association mathematically. In this study, we performed a systematic review and meta-analysis, using strict inclusion criteria, to more precisely assess the malignant potential rate of OLP and the influence of associated risk factors. All reports that documented MT of OLP and published in the English language until January 2020 were included if they met the following strict criteria: (a) the presence of a properly verified OLP diagnosis, (b) a clear description of the cancerous lesion developing at the same site as the verified OLP lesion; and (c) a follow-up period of a minimum of 6months prior to carcinoma development. Thirty-three studies were included in this analysis with a total of 12838 OLP patients. Of these, 151 cases were initially considered to have progressed to carcinoma (1.2%). However, after applying strict criteria, only 56 cases were considered to have undergone MT from OLP (0.44%). The risk of MT was significantly higher among OLP patients who smoked (OR=4.62), consumed alcohol (OR=3.22), were seropositive for HCV (OR=3.77) and/or displayed a red OLP subtype (OR=0.37). Our results suggest that the reported OLP malignant transformation rates are exaggerated, and these do not reflect the actual clinical course of the disease according to strict clinical and histopathological criteria.

Association of MAPK and its regulatory miRNAs (603, 4301, 8485, and 4731) with the malignant transformation of oral lichen planus.

Oral lichen planus (OLP) is a potentially malignant oral lesion that may transform into oral squamous cell carcinoma (OSCC). The purpose of this study was to assess the level of expression of MAPK/ERK1/2 gene, and microRNA (miR)-603, 4301, 8485, and 4731 in the MAPK signaling pathway in OLP and OSCC lesions. This case-control study evaluated 26 OSCC, 20 OLP and 20 healthy control tissue specimens. After RNA extraction, the respective miRNA and MAPK/ERK1/2 mRNA levels were assessed by quantitative reverse transcription polymerase chain reaction (RT-PCR). Significant upregulation of MAPK/ERK1/2 gene was noted in the OLP and OSCC specimens compared with healthy controls (p < 0.001). The expression level of miR-4731 was significantly lower in the OLP and OSCC specimens than in the healthy specimens (p < 0.001). The expression of MiR-603 was the lowest in OLP, followed by OSCC and then the control group (p < 0.001). No significant difference was found in miR-4801 levels between OSCC and OLP specimens compared with healthy controls (p = 0.43 and p = 0.86, respectively). In addition, a non-significant decrease in miR-8485 levels was noted in the OSCC and OLP specimens compared with healthy controls (p = 0.98 and p = 0.61, respectively). A significant decrease in level of miR-603 was noted in OLP compared with OSCC group (p < 0.001). The miR-4801 and miR-8485 expression levels were directly correlated with MAPK/ERK1/2 mRNA expression (p = 0.01). Higher expression level of MAPK/ERK1/2, miR-603, miR-4801, and miR-4731, and lower expression level of miR-8485 were correlated with significantly lower overall survival rate in OSCC patients. The increased expression of MAPK/ERK1/2 and decreased expression of miR-603 and miR-4731 are associated with greater risk of OLP malignant transformation and poor histopathological characteristics of OSCC.

Narrow-band imaging: a useful tool for early recognition of oral lichen planus malignant transformation?

Oral lichen planus (OLP) lesions have an overall malignant transformation rate of 1.37%. In patients with chronic disease, the diagnosis of malignancy relies on histopathological examination guided by clinical suspicion. Narrow-band imaging (NBI) is a promising endoscopic technique which, using a filtered light with specific wavelengths, can highlight microvascular abnormalities associated with subclinical neoplastic changes of the upper aerodigestive tract epithelium. This study aimed to analyse the value of NBI in selecting patients for biopsy before the emergence of clinical changes, allowing early detection of oral malignancies arising from OLP. A prospective study was conducted, enrolling 32 consecutive patients with a histological diagnosis of OLP with no previous diagnosis of oral cancer or other oral inflammatory diseases. Patients with suspicious NBI lesions underwent biopsies, while other patients were included in the follow-up. Two patients were judged positive at NBI evaluation and squamous cell carcinoma was diagnosed after histological examination. None of the other patients developed clinical features of malignancies during follow-up. NBI evaluation may increase the accuracy of detection of subclinical neoplastic transformation in OLP lesions and further encourage clinicians to perform biopsies in selected cases.

Candida albicans induces TLR2/MyD88/NF-κB signaling and inflammation in oral lichen planus-derived keratinocytes.

The risk of oral lichen planus (OLP), a chronic inflammatory oral mucosal disease, becoming malignant increases by 21-fold in patients with fungal infection. This study examined the impact of Candida albicans exposure on Toll-like receptor (TLR) signaling in primary keratinocyte cultures obtained from OLP patients. Following co-culture of primary OLP keratinocyte cultures with C. albicans for 24 hours, inflammatory cytokine concentrations were determined by ELISA. TLR2, MyD88, and NF-κBp65 mRNA and protein expression were assessed using quantitative RT-PCR and Western blot analyses, respectively. Keratinocyte apoptosis was also determined by flow cytometry. IL-10, IL-8, IL-2, and TNF-ɑ levels were significantly higher following co-culture with C. albicans (all p ≤ 0.034). MyD88, NF-κB p65, and TLR2 mRNA (all p < 0.001) and protein (all p ≤ 0.004) expression levels were significantly higher in OLP keratinocytes following C. albicans exposure. Finally, the apoptosis rates of OLP keratinocytes were 21.2%, 29.4%, and 25.4% for the control cells and 3.9%, 5.6%, and 4.4% for those exposed to C. albicans, suggesting that co-culture with C. albicans inhibits the apoptosis of OLP keratinocytes. C. albicans activates the TLR2/MyD88/NF-κB signaling pathway in OLP keratinocytes, resulting in increased cytokine expression and decreased keratinocyte apoptosis. Two key events in the pathogenesis of OLP and its progression to malignancy, namely increased inflammation and decreased apoptosis, were induced by exposure to C. albicans. Thus, targeting this signaling pathway may represent a novel therapeutic strategy to prevent OLP malignant transformation.