Cucurbitacin B induces ferroptosis in oral leukoplakia via the SLC7A11/mitochondrial oxidative stress pathway.

BACKGROUND: Oral leukoplakia (OLK), characterized by abnormal epithelial hyperplasia, is the most common precancerous oral mucosa lesion and is closely related to oxidative stress. Cucurbitacin B (CuB), a tetracyclic triterpenoid molecule derived from plants, has shown promising anti-proliferative and antioxidant effects in preclinical studies. However, whether CuB can play an antiproliferative role in OLK by regulating oxidative stress remains elusive. PURPOSE: To investigate the role of CuB in inhibiting the malignant progression of oral leukoplakia and to further explore its underlying mechanisms of action. METHODS: In vitro, the effect of CuB on the proliferation, migration, apoptosis, and cell cycle of OLK cells DOK was detected. The core genes and key pathways of OLK and CuB were analyzed in the transcriptome database, by using immunofluorescence, qRT-PCR, and Western blot to evaluate the expression levels of the ferroptosis markers ROS, GSH, MDA, Fe2+, and marker genes SLC7A11, GPX4, and FTH1. Immunohistochemistry of human tissue was performed to investigate the expression of the SLC7A11. In vivo, the model of OLK was established in C57BL/6 mice and the biosafety of CuB treatment for OLK was further evaluated. RESULTS: CuB substantially suppressed the proliferation of DOK cells. Bioinformatics analysis showed that the core targets of OLK crossing with CuB include SLC7A11 and that the essential pathways involve ROS and ferroptosis. In vitro experiments indicated that CuB might promote ferroptosis by down-regulating the expression of SLC7A11. We observed a gradual increase in SLC7A11 expression levels during the progression from normal oral mucosa to oral leukoplakia with varying degrees of epithelial dysplasia. In vivo experiments demonstrated that CuB inhibited the malignant progression of OLK by promoting ferroptosis in OLK mice and exhibited a certain level of biosafety. CONCLUSION: This study demonstrated for the first time that CuB could effectively inhibit the malignant progression of OLK by inducing ferroptosis via activating the SLC7A11/ mitochondrial oxidative stress pathway. These findings indicate that CuB could serve as the lead compound for the future development of anti-oral leukoplakia drugs.

Comparison of Effectiveness of Moringa Oleifera Leaves Extract Gel (2%) with Retino A (0.1%) Cream for Treatment of Oral Leukoplakia: Double Blinded Randomized Control Trial.

AIM: The study aims to evaluate and compare the efficacy of Moringa oleifera leaf extract gel (2%) & Retino A cream (0.1%) in reducing the size of lesions in oral leukoplakia. OBJECTIVES: The present study aimed to evaluate the efficacy of two interventions, Moringa oleifera mucoadhesive gel and Retino-A cream, in reducing the size of lesions in patients with oral leukoplakia. Specifically, the objectives were: (1) to assess the efficacy of Moringa oleifera mucoadhesive gel in determining the reduction in lesion size, (2) to assess the efficacy of Retino-A cream in determining the reduction in lesion size, and (3) to compare the efficacy of Moringa oleifera mucoadhesive gel (2%) in determining the change in lesion size in oral leukoplakia patients. METHODS: Clinically diagnosed cases of oral Leukoplakia were included in this study. The sample size is 72. Thirty-six patients had lesion sizes ranging from 2- 4 cm, and 36 patients had lesion sizes ranging from 4.1 - 6 cm that were equally distributed in the case and control groups using the chit system. The case and control groups had 36 patients with an equal size range of lesions. The case and control group participants will be advised topical application of the intervention and Retino-A thrice daily using a sterile cotton bud. RESULTS: M. oleifera gel (2%) was found to be more effective in the reduction in the size of the lesion as compared to Retino-A in the treatment of oral leukoplakia patients. CONCLUSION: This study showed that M. oleifera mucoadhesive gel (2%) is an effective and safe treatment option for oral leukoplakia patients. It demonstrated a significant reduction in lesion size compared to Retino-A cream (0.1%) after 3 months of therapy, without any reported adverse effects. However, long-term follow-up studies are needed to evaluate its long-term effectiveness. The potent antioxidant property of M. oleifera makes it a promising candidate for further studies with concentration variations and in other potentially malignant oral disorders, such as lichen planus and OSMF. The development of chemotherapeutic drugs from M. oleifera for cancer treatment should also be considered. Overall, M. oleifera appears to be a promising natural alternative to synthetic drugs for the treatment of oral leukoplakia. KEY WORDS: Leukoplakia, Oral leukoplakia, premalignant lesion, precancer, potentially malignant disorders.

Eficacia clínica de la terapia fotodinámica por 5-ALA tópico en el manejo onco-preventivo de lesiones de leucoplasia oral. Una revisión sistemática / Clinical efficacy of topical 5-ALA photodynamic therapy in the onco-preventive management of oral leukoplakia lesions. A systematic review

Objetivo: La leucoplasia oral es el desorden maligno de la mucosa bucal más prevalente a nivel global y su manejo clínico sigue siendo un desafío. Se llevó a cabo una revisión sistemática para determinar la eficacia clínica de la terapia fotodinámica mediada por ácido 5-aminolevulínico tópico como una alternativa de quimio-prevención para las diferen- tes formas clínicas de la leucoplasia oral. Materiales y métodos: Empleando términos MeSH, se realizó una búsqueda exhaustiva en diferentes bases digi- tales de ensayos clínicos publicados en inglés en los últimos 30 años acerca del uso de la terapia fotodinámica mediada por ácido 5-aminolevulínico tópico como fotosensibilizador, y radiación láser de baja intensidad o luz LED como posibles fuentes de iluminación. Resultados: La revisión sistematizada que aplicó la guía PRISMA mostró una eficacia del 88,6% para este modo de fototerapia en el manejo de leucoplasias orales, con un 60,7% de respuesta completa y 27,9% de respuesta parcial. Además, el tamaño de efecto fue mayor para las formas clíni- cas homogéneas con cambios displásicos, independientemen- te del tipo de fuente de luz. La ausencia de respuesta fue del 11,4%, pero la evidencia empleada en este análisis fue mo- derada. Conclusión: La terapia fotodinámica mediada por áci- do 5-aminolevulínico tópico parece ser una alternativa útil en el manejo onco-preventivo de lesiones de leucoplasia oral. Sin embargo, es recomendable ejecutar ensayos clínicos controla- dos y aleatorizados con metodologías homogéneas que per- mitan generar un meta-análisis con un alto nivel de evidencia

Aim: Oral leukoplakia is globally the most prevalent ma- lignant disorder of the oral mucosa and its clinical manage- ment remains a challenge. A systematic review was carried out to determine the clinical efficacy of photodynamic therapy mediated by topical 5-aminolevulinic acid as an alternative for chemoprevention in the different clinical forms of oral leu- koplakia. Materials and methods: Using MeSH terms, an ex- haustive search was carried out in different digital databases of clinical trials published in English in the last 30 years on the use of photodynamic therapy mediated by topical 5-ami- nolevulinic acid as a photosensitizer, and low-intensity laser radiation or LED light as possible lighting sources. Results: The systematized review using PRISMA guide- lines showed an efficacy of 88.6% for this mode of photother- apy in the management of oral leukoplakias, based on 60.7% of complete response and 27.9% of partial response. In addi- tion, the effect size was larger in homogeneous clinical forms with dysplastic changes, regardless of the type of light source. There was an 11.4% of absence of response, but the evidence used in this analysis was moderate. Conclusion: Photodynamic therapy mediated by topical 5-aminolevulinic acid seems to be a useful alternative in the onco-preventive management of oral leukoplakia lesions. However, it is recommendable to perform controlled and ran- domized clinical trials with homogeneous methodologies that allow the generation of a meta-analysis with a high level of evidence (AU)

Deciphering the pharmacological mechanisms of Scutellaria baicalensis Georgi on oral leukoplakia by combining network pharmacology, molecular docking and experimental evaluations.

BACKGROUND: Oral leukoplakia (OLK), an uncharacterized pathological condition that occurs as a white patch in the oral mucosa, is the most common precancerous condition. Scutellaria baicalensis Georgi (SBG) is a medicinal plant with a wide range of pharmacological effects. Increased evidence shows that SBG has potential therapeutic effects on OLK. However, the therapeutic mechanisms of SBG against OLK have not yet been completely elucidated. PURPOSE: This study aimed to clarify the active components and multi-target mechanisms of SBG against OLK via network pharmacology, molecular docking and experimental evaluations. STUDY DESIGN AND METHODS: The active components and related targets of SBG were screened by the TCMSP database and Swiss Target Prediction database. Potential therapeutic targets of OLK were collected using the GeneCards and OMIM databases. Then, we established protein-protein interaction (PPI), compound-target-disease (C-T-D), and compound-target-pathway (C-T-P) networks by Cytoscape to identify the main components, core targets, and pharmacological pathways of SBG against OLK via applying data mining techniques and topological parameters. Metascape database was utilized for GO and KEGG pathway analysis. Molecular docking techniques were used to estimate the binding force between the components and the hub genes. Subsequently, a series of in vitro experiments, specifically CCK-8 assay, clone formation assay, wound healing assay, flow cytometry, RT-qPCR and western blotting were conducted for further verification. RESULTS: There were 25 active components and 31 related target genes in SBG against OLK. PPI analysis showed that Akt1, VEGFA, EGFR, HIF1A and PTGS2 shared the highest centrality among all target genes. KEGG pathway analysis found that PI3K-Akt signaling pathway may occupy core status in the anti-OLK system. Molecular docking results showed that the main active components of SBG had a strong binding affinity to the hub genes. In vitro experiments showed that the leading component baicalein may inhibit proliferation, block cells in the S phase, induce DOK cell apoptosis, and downregulate the mRNA expression of 5 hub genes by inhibiting PI3K/Akt signaling pathway activation. CONCLUSION: The most predominant component of SBG against OLK was baicalein and the key pathway was PI3K/Akt. The main components and hub genes had robust binding abilities. In vitro experiments showed that baicalein could inhibit the proliferation of DOK cells, induce apoptosis, block the cell cycle, and inhibit the mRNA expression level of the hub genes by inhibiting the PI3K/Akt pathway.

Imunoexpressão da Yes-Associated Protein (YAP) em hiperceratoses e displasias epiteliais orais / Immunoexpression of Yes-Associated Protein (YAP) in hyperkeratosis and oral epithelial dysplasia

A busca por um biomarcador que auxilie na predição de risco de transformação maligna das desordens orais potencialmente malignas (DOPMs) representa um grande desafio, já que pode auxiliar no manejo precoce e adequado dos pacientes. Este estudo avaliou a imunoexpressão da Yes-Associated Protein (YAP) em lesões intraorais leucoplásicas, eritroplásicas ou leucoeritroplásicas, com diagnóstico histopatológico de hiperceratose ou displasia epitelial oral (DEO), correlacionando essa imunoexpressão com o grau de severidade morfológica dessas lesões. A amostra foi composta por 20 casos de hiperceratoses e 53 casos de DEOs, além de 10 casos de mucosa oral normal (grupo controle). Para a avaliação do grau de displasia, foram utilizadas as gradações da OMS (EL-NAGGAR et al., 2017) e o Sistema Binário (KUJAN et al., 2006), sendo o perfil imunoistoquímico da proteína YAP avaliado por meio de escores, que variaram entre 0 e 3, com base em sua localização intracelular (citoplasmática ou nuclear) e por sua distribuição no tecido epitelial. Para a análise entre os parâmetros estudados foram realizados os testes estatísticos Qui-quadrado de Pearson, Exato de Fisher, além de testes não paramétricos, (nível de significância de 95%). Displasias leves foram enquadradas (100%) no baixo risco de transformação maligna, enquanto as moderadas dividiram-se entre baixo (47%) e alto risco (53%), sendo as displasias severas, em sua maior parte (71%), classificadas como de alto risco (p < 0,001). O grupo controle exibiu imunomarcação de escore 0 (80%), as hiperceratoses e displasias leves (em 80% das vezes) exibiram escore 1, já nas displasias moderadas (63%) e severas (79%), foram predominantes os escores 2 e 3; com padrão de imunomarcação nuclear associado ao alto risco de transformação maligna sugerido pelo Sistema binário (p = 0,002). A imunoexpressão da YAP foi semelhante entre hiperceratoses e displasias leves, o que deve suscitar maior atenção dos profissionais frente aos casos de hiperceratose, além disto a expressão da YAP aparenta dicotomizar as DOPMs entre as lesões com baixo risco de transformação maligna e as lesões com alto risco, o que pode sugerir no futuro, sua utilização como potencial marcador preditivo de progressão destas lesões (AU).

The search for a biomarker that helps to predict the risk of malignant transformation of oral potentially malignant disorders (OPMDs) represents a great challenge, as it can help in the early and adequate management of patients. This study evaluated the immunoexpression of Yes-Associated Protein (YAP) in intraoral leukoplastic, erythroplastic or leukoerythroplastic lesions, with histopathological diagnosis of hyperkeratosis or oral epithelial dysplasia (OED), correlating this immunoexpression with the degree of morphological severity of these lesions. The sample consisted of 20 cases of hyperkeratosis and 53 cases of OED, in addition to 10 cases of normal oral mucosa (control group). To assess the degree of dysplasia, the WHO grading (EL-NAGGAR et al., 2017) and the Binary System (KUJAN et al., 2006) were used, and the immunohistochemical profile of the YAP protein was evaluated through scores, which ranged from 0 to 3, based on their intracellular location (cytoplasmic or nuclear) and their distribution in the epithelial tissue. For the analysis of the studied parameters, Pearson's Chi-square and Fisher's Exact statistical tests were performed, in addition to non-parametric tests (significance level of 95%). Mild dysplasias were classified (100%) in the low risk of malignant transformation, while the moderate ones were divided between low (47%) and high risk (53%), with severe dysplasias, for the most part (71%), classified as high risk (p < 0.001). The control group exhibited score 0 of immunostaining (80%), hyperkeratosis and mild dysplasias (80% of booth) exhibit score 1, whereas in moderate (63%) and severe dysplasia (79%), the predominant scores was 2 and 3; with a pattern of nuclear immunostaining associated with the high risk of malignant transformation suggested by the Binary System (p = 0.002). The immunoexpression of YAP was similar between hyperkeratosis and mild dysplasias, which should attract greater attention from professionals in cases of hyperkeratosis. Furthermore, the expression of YAP appears to dichotomize OPMDs between lesions with low risk of malignant transformation and lesions with high risk, which may suggest, in the future, its use as a potential predictive marker of the progression for these lesions (AU).

Correlation Between Clinical and Histopathologic Diagnosis of Oral Potentially Malignant Disorder and Oral Squamous Cell Carcinoma

ABSTRACT Objective: To determine the frequency of oral potentially malignant disorders and Oral Squamous Cell Carcinoma (OSCC) and evaluate the consistency between their clinical and pathological features. Material and Methods: This retrospective study was conducted on records with a diagnosis of oral leukoplakia, oral erythroplakia, erythroleukoplakia, actinic cheilitis, lichen planus, and OSCC in the Pathology Department of Kerman dental school from September 1997 to September 2017. Data were analyzed in SPSS 21 at the significance level of ≤5%. Results: There were 378 cases of oral potentially malignant disorders and 70 cases of OSCC with a mean age of 46.82 ± 15.24 years. Buccal mucosa was the most frequent site, and lichen planus the most common lesion. Females were significantly older than males in leukoplakia and carcinoma in situ lesions. Clinical diagnosis and histopathology were consistent in 69.03% of cases. Conclusion: Clinical and histopathological diagnoses were consistent in 69.03% of records. The highest degree of clinical compliance with histopathology was observed in OSCC. Dentists should pay attention to oral potentially malignant disorders for early diagnosis to prevent their transformation to malignancy.

Plum-blossom needle assisted photodynamic therapy for the treatment of oral potentially malignant disorder in the elderly.

Oral leukoplakia (OLK) is one of the most common oral potentially-malignant disorders (OPMD) with complex causes, a long disease course and a high tendency for recrudescence. Although a variety of methods exist for treating this disease, canceration rates remain high. Herein, we described a case of 72-year-old male patient with OLK of the palatine mucous membrane who had achieved complete remission after being treated with five sessions of plum-blossom needle (PBN) assisted 5-aminolevulinic acid-photodynamic therapy (ALA-PDT). The patient had since been subsequently placed under close observation (>12 mo). To date, there has been no recurrence. PBN assisted PDT might be suitable for the treatment of OPMDs in patients presenting with epithelial hyperkeratosis.

Effects of Black Raspberry Extract and Berry Compounds on Repair of DNA Damage and Mutagenesis Induced by Chemical and Physical Agents in Human Oral Leukoplakia and Rat Oral Fibroblasts.

Black raspberries (BRB) have been shown to inhibit carcinogenesis in a number of systems, with most studies focusing on progression. Previously we reported that an anthocyanin-enriched black raspberry extract (BE) enhanced repair of dibenzo-[a,l]-pyrene dihydrodiol (DBP-diol)-induced DNA adducts and inhibited DBP-diol and DBP-diolepoxide (DBPDE)-induced mutagenesis in a lacI rat oral fibroblast cell line, suggesting a role for BRB in the inhibition of initiation of carcinogenesis. Here we extend this work to protection by BE against DNA adduct formation induced by dibenzo-[a,l]-pyrene (DBP) in a human oral leukoplakia cell line (MSK) and to a second carcinogen, UV light. Treatment of MSK cells with DBP and DBPDE led to a dose-dependent increase in DBP-DNA adducts. Treatment of MSK cells with BE after addition of DBP reduced levels of adducts relative to cells treated with DBP alone, and treatment of rat oral fibroblasts with BE after addition of DBPDE inhibited mutagenesis. These observations showed that BE affected repair of DNA adducts and not metabolism of DBP. As a proof of principle we also tested aglycones of two anthocyanins commonly found in berries, delphinidin chloride and pelargonidin chloride. Delphinidin chloride reduced DBP-DNA adduct levels in MSK cells, while PGA did not. These results suggested that certain anthocyanins can enhance repair of bulky DNA adducts. As DBP and its metabolites induced formation of bulky DNA adducts, we investigated the effects of BE on genotoxic effects of a second carcinogen that induces bulky DNA damage, UV light. UV irradiation produced a dose-dependent increase in cyclobutanepyrimidine dimer levels in MSK cells, and post-UV treatment with BE resulted in lower cyclobutanepyrimidine dimer levels. Post-UV treatment of the rat lacI cells with BE reduced UV-induced mutagenesis. Taken together, the results demonstrate that BE extract reduces bulky DNA damage and mutagenesis and support a role for BRB in the inhibition of initiation of carcinogenesis.

Chemoprevention of oral cancer in leukoplakia patients: A systematic review and meta-analysis.

The systematic review and meta-analysis of published randomised controlled trials (RCTs) was conducted to review the effectiveness of current chemopreventive agents in the treatment of oral leukoplakia lesions (OPLs) and prevention of their progression to oral cancer. Material was identified through a retrospective literature search of the electronic PubMed database, Embase and Cochrane Library between 2008 and 2016.Eight RCTs were included for systematic review. The pooled estimate showed a 14% greater chance of responding for those randomised to interventions compared with placebo (Risk Ratio [RR] 1.14, 95% confidence interval [CI] 0.72 to 1.81). The CI from individual studies overlapped. The results suggested that there were no significant differences in comparing clinical responses between chemopreventive agents with placebo in treatment of OPLs. It is time to investigate new agents for oral cancer chemoprevention.

p53 and ki67 as biomarkers in determining response to chemoprevention for oral leukoplakia.

BACKGROUND: We performed a randomized controlled chemoprevention trial of oral leukoplakia by administrating a low dose of beta-carotene and vitamin C supplements. 17% of subjects in the experimental arm (4/23) demonstrated clinical remission (complete or partial response) at completion of the trial. The objective of this study was to determine whether baseline expression of p53 and ki67 demonstrated any differences between those responding or not responding to our intervention. A secondary objective was to elucidate any relationship between dietary factors and clinical responses. METHODS: For this biomarker study, we included all subjects in the experimental group (n = 23) who were non-smokers. Among 16 who completed the trial for 1 year of supplementation, there were four responders and 12 non-responders at 1-year follow-up. Following immuno-staining for p53 and ki67, the percentage of positive cell nuclei were analyzed as labeling index (LI). RESULTS: Expression of p53 was greater in basal layers than in para-basal layers. Mean para-basal LI of p53 was higher in non-responding (26.0) than in responding subjects (11.2) (P = 0.028). ki67 LIs were not significantly different in the two groups. CONCLUSIONS: Expression of p53 was inversely related to clinical response to the supplements. Other biomarkers that may recognize subject's responsiveness to chemoprevention require further study.

Interventions for treating oral leukoplakia to prevent oral cancer.

BACKGROUND: Oral leukoplakia is a relatively common oral lesion that, in a small proportion of people, precedes the development of oral cancer. Most leukoplakias are asymptomatic; therefore, the primary objective of treatment should be to prevent onset of cancer. This review updates our previous review, published in 2006. OBJECTIVES: To assess the effectiveness, safety and acceptability of treatments for leukoplakia in preventing oral cancer. SEARCH METHODS: We searched the following electronic databases: Cochrane Oral Health's Trials Register (to 16 May 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 4), MEDLINE Ovid (1946 to 16 May 2016), Embase Ovid (1980 to 16 May 2016) and CancerLit via PubMed (1950 to 16 May 2016). We searched the metaRegister of Controlled Trials (to 10 February 2015), ClinicalTrials.gov (to 16 May 2016) and the World Health Organization (WHO) International Clinical Trials Registry Platform for ongoing trials (to 16 May 2016). We placed no restrictions on the language or date of publication when searching electronic databases. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that enrolled people with a diagnosis of oral leukoplakia and compared any treatment versus placebo or no treatment. DATA COLLECTION AND ANALYSIS: We collected data using a data extraction form. Oral cancer development, demonstrated by histopathological examination, was our primary outcome. Secondary outcomes were clinical resolution of the lesion, improvement of histological features and adverse events. We contacted trial authors for further details when information was unclear. When valid and relevant data were available, we conducted a meta-analysis of the data using a fixed-effect model when we identified fewer than four studies with no heterogeneity. For dichotomous outcomes, we calculated risk ratios (RRs) and 95% confidence intervals (CIs). We assessed risk of bias in studies by using the Cochrane tool. We assessed the overall quality of the evidence by using standardised criteria (Grades of Recommendation, Assessment, Development and Evaluation Working Group (GRADE)). MAIN RESULTS: We included 14 studies (909 participants) in this review. Surgical interventions, including laser therapy and cryotherapy, have never been studied by means of an RCT that included a no treatment or placebo arm. The included trials tested a range of medical and complementary treatments, in particular, vitamin A and retinoids (four studies); beta carotene or carotenoids (three studies); non-steroidal anti-inflammatory drugs (NSAIDs), specifically ketorolac and celecoxib (two studies); herbal extracts (four studies), including tea components, a Chinese herbal mixture and freeze-dried black raspberry gel; bleomycin (one study); and Bowman-Birk inhibitor (one study).We judged one study to be at low risk of bias, seven at unclear risk and six at high risk. In general, we judged the overall quality of the evidence to be low or very low, so findings are uncertain and further research is needed.Five studies recorded cancer incidence, only three of which provided useable data. None of the studies provided evidence that active treatment reduced the risk of oral cancer more than placebo: systemic vitamin A (RR 0.11, 95% CI 0.01 to 2.05; 85 participants, one study); systemic beta carotene (RR 0.71, 95% CI 0.24 to 2.09; 132 participants, two studies); and topical bleomycin (RR 3.00, 95% CI 0.32 to 27.83; 20 participants, one study). Follow-up ranged between two and seven years.Some individual studies suggested effectiveness of some proposed treatments, namely, systemic vitamin A, beta carotene and lycopene, for achieving clinical resolution of lesions more often than placebo. Similarly, single studies found that systemic retinoic acid and lycopene may provide some benefit in terms of improvement in histological features. Some studies also reported a high rate of relapse.Side effects of varying severity were often described; however, it seems likely that interventions were well accepted by participants because drop-out rates were similar between treatment and control groups. AUTHORS' CONCLUSIONS: Surgical treatment for oral leukoplakia has not been assessed in an RCT that included a no treatment or placebo comparison. Nor has cessation of risk factors such as smoking been assessed. The available evidence on medical and complementary interventions for treating people with leukoplakia is very limited. We do not currently have evidence of a treatment that is effective for preventing the development of oral cancer. Treatments such as vitamin A and beta carotene may be effective in healing oral lesions, but relapses and adverse effects are common. Larger trials of longer duration are required to properly evaluate the effects of leukoplakia treatments on the risk of developing oral cancer. High-quality research is particularly needed to assess surgical treatment and to assess the effects of risk factor cessation in people with leukoplakia.

A Randomized Double-Blind Placebo-Controlled Phase IIB Trial of Curcumin in Oral Leukoplakia.

Oral leukoplakia is a potentially malignant lesion of the oral cavity, for which no effective treatment is available. We investigated the effectiveness of curcumin, a potent inhibitor of NF-κB/COX-2, molecules perturbed in oral carcinogenesis, to treat leukoplakia. Subjects with oral leukoplakia (n = 223) were randomized (1:1 ratio) to receive orally, either 3.6 g/day of curcumin (n = 111) or placebo (n = 112), for 6 months. The primary endpoint was clinical response obtained by bi-dimensional measurement of leukoplakia size at recruitment and 6 months. Histologic response, combined clinical and histologic response, durability and effect of long-term therapy for an additional six months in partial responders, safety and compliance were the secondary endpoints. Clinical response was observed in 75 (67.5%) subjects [95% confidence interval (CI), 58.4-75.6] in the curcumin and 62 (55.3%; 95% CI, 46.1-64.2) in placebo arm (P = 0.03). This response was durable, with 16 of the 18 (88.9%; 95% CI, 67.2-96.9) subjects with complete response in curcumin and 7 of 8 subjects (87.5%) in placebo arm, demonstrating no relapse after 6 months follow-up. Difference in histologic response between curcumin and placebo was not significant (HR, 0.88, 95% CI, 0.45-1.71; P = 0.71). Combined clinical and histologic response assessment indicated a significantly better response with curcumin (HR, 0.50; 95% CI, 0.27-0.92; P = 0.02). Continued therapy, in subjects with partial response at 6 months, did not yield additional benefit. The treatment did not raise any safety concerns. Treatment of oral leukoplakia with curcumin (3.6 g for six months), thus was well tolerated and demonstrated significant and durable clinical response for 6 months. Cancer Prev Res; 9(8); 683-91. ©2016 AACR.

Treatment of oral leukoplakia with a low-dose of beta-carotene and vitamin C supplements: a randomized controlled trial.

Management of oral leukoplakia-a potentially malignant disorder-is currently not evidence-based. Of the few randomized trials that have been reported, most have negative data. Therefore, a multi-centre, randomized, double-blind controlled trial (RCT) was undertaken to evaluate the use of low-dose beta-carotene combined with vitamin C supplements for the treatment and to prevent malignant transformation of oral leukoplakia. 46 Japanese participants with oral leukoplakia were allocated randomly either to an experimental arm (10 mg day(-1) of beta-carotene and 500 mg day(-1) of vitamin C) or placebo arm (50 mg day(-1) of vitamin C). Current or ex-smokers within 3 months of cessation were excluded. The supplements were continued over a period of 1 year. The primary endpoint was clinical remission at 1-year and the likelihood of malignant transformation during a 5-year follow-up period as a secondary endpoint. The overall clinical response rate in the experimental arm was 17.4% (4/23) and 4.3% (1/23) in the placebo arm (p = 0.346). During the median 60-month follow-up period, two subjects in the experimental arm and three in the control arm developed oral cancer. Under the intention-to-treat principle, relative risk by supplementing with beta-carotene and vitamin C was 0.77 (95%CI: 0.28-1.89) (p = 0.580) by the Cox proportional hazards model. No unfavorable side-effects were noted. Beta-carotene (10 mg day(-1) ) and vitamin C were neither effective for clinical remission, nor for protection against the development of cancer. Data from this RCT does not support the hypothesis that chemoprevention with this treatment is effective for oral leukoplakia.

Avaliação da expressão do KI-67 e do BMI-1 em leucoplasias bucais displásicas e não displásicas / Evaluation of Ki-67 and BMI-1 expression in non-dysplastic and dysplastic oral leukoplakias

Leucoplasia bucal (LB) é uma desordem potencialmente maligna, com risco de transformação maligna que varia de 0,13% a 17,5%. Muitos estudos vêm buscando estabelecer biomarcadores capazes de predizer o potencial de transformação maligna dessa lesão. O Ki-67 é uma proteína não-histônica nuclear que tem sido amplamente utilizada para avaliar proliferação celular. O BMI-1 é uma proteína considerada um marcador essencial para a manutenção das propriedades de autorrenovação e da tumorigenicidade do carcinoma espinocelular. O objetivo principal desse estudo observacional transversal foi avaliar proliferação e imortalização celulares em LB a partir da marcação imunoistoquímica do Ki-67 e do BMI-1, comparando lesões displásicas com não displásicas. Casos de LB não displásica - LBND (n=28), LB displásica - LBD (n=33) foram selecionados a partir de prontuários de pacientes e comparados com mucosa clinicamente normal - MN (n=9), hiperplasia inflamatória - HI (n=17) e carcinoma espinocelular - CEC (n=19). Os diagnósticos histopatológicos foram confirmados a partir da revisão de cortes histológicos corados por hematoxilina e eosina. Adicionalmente, cortes histológicos foram submetidos à técnica imunoistoquímica para avaliação de Ki-67 e BMI-1. Para a quantificação foi considerado o percentual de células positivas por 1000 células para o CEC e 1500 células para os demais grupos. O percentual de imunomarcação de Ki-67 e de BMI-1, quando avaliadas todas as camadas epiteliais em conjunto, foi mais alto no CEC quando comparado aos demais grupos (Kruskal-Wallis, p<0.05). A expressão de Ki-67 foi maior em LBND, LBD e HI quando comparada com MN (Kruskal-Wallis, p<0.05)...

Oral leukoplakia (OL) is potentially malignant disorder, with a risk of malignant transformation that ranges from 0.13% to 17.5%. Many biological markers have been used as an attempt to predict malignant transformation, but no reliable markers have been established so far. The Ki-67 is a nuclear non-histone regarded as reliable marker of proliferating cells .BMI-1 is a protein considered as an essential marker for maintenance of properties self-renewability and tumorigenicity of squamous cell carcinoma. The main aim this cross-sectional observational study was to evaluate cell proliferation and immortalization in oral leukoplakia, comparing non-dysplastic and dysplastic lesions. Cases of non-dysplastic – Non-dys OL (n=28), dysplastic – Dys OL (n=33) records were selected and compared with normal oral mucosa – NOM (n=9), inflammatory hyperplasia –IH (n=17), and oral squamous cell carcinoma - OSCC (n=19). The histopathological diagnosis was confirmed by the revision of Hematoxilin and Eosin stained slides. Additionally, histological sections were submitted to immunohistochemical technique for evaluation of Ki-67 and BMI-1. The labeling index was determined by counting the labeled nuclei of 1000 cells for OSCC cases and 1500 for the others comparison groups. Ki-67 and BMI-1 immunolabeling percentage were higher in OSCC in comparison of others groups when all epithelial layers were evaluated together (Kruskal-Wallis, p<0.05). Ki-67 immunolabeling increased in Non-dys OL, Dys OL and IH when compared to NOM (Kruskal-Wallis, p<0.05). Furthermore, BMI-1 immunolabeling was higher in Dys OL relation to NOM in the analysis of all epithelial layers together (Kruskal-Wallis, p<0.05)...

HBO: a possible supplementary therapy for oral potentially malignant disorders.

Oral potentially malignant disorders (OPMDs) are chronic inflammatory diseases in which cells suffer hypoxia referring to deprivation of adequate oxygen supply. Hyperbaric oxygen treatment (HBO), which can increase oxygen tension and delivery to oxygen-deficient tissue, is a supplementary therapy to improve or cure disorders involving hypoxia. Although the applications of HBO in wound healings, acute ischemic stroke, radiation-induced soft tissue injury and cancers are extensively reported, there are only few studies on their effect in OPMDs. Not only does HBO furnish oxygen-it also possesses potent anti-inflammatory properties. At the cellular level, HBO can decrease lymphocyte proliferation and promote apoptosis of fibroblasts. At the molecular level, it can decrease expression of HIF, ICAM-1, TNF-α, TGF-ß, and IFN-γ, as well as increase vascular VEGF expression and angiogenesis. Thus, we hypothesize that HBO may contribute to treat OPMDs, including oral lichen planus, oral leukoplakia, and oral submucous fibrosis both at the cellular level and the molecular level, and that it would be a safe and inexpensive therapeutic strategy.

Clinical evaluation of photodynamic therapy efficacy in the treatment of oral leukoplakia.

BACKGROUND: The aim of the study was clinical evaluation of photodynamic therapy efficacy in the treatment of oral leukoplakia lesions. METHODS: Twenty-three consecutive patients aged 21-79 were included to the study. In all patients 44 homogeneous, flat leukoplakia lesions were clinically diagnosed and confirmed histopathologically. Photodynamic therapy was performed with the use of Photolon(®) photosensitizer, containing 20% Chlorine-e6 and 10% dimethyl sulfoxide and a semiconductor laser, with power up to 300mW and a wavelength of 660nm. Ten illumination sessions were conducted with the use of superficial light energy density of 90J/cm(2). RESULTS: At baseline the mean size of leukoplakia lesion was 6.5±5.10cm(2) while after photodynamic therapy 3±2.99cm(2). Significant reduction (on average by 53.8%) of leukoplakia lesions sizes was observed after therapy. Twelve (27.27%) lesions had been completely cured, 22 (50%) partially cured, although 10 (22.73%) lasted unchanged. The efficacy of PTD was comparable in women and men irrespective of age. There have been no adverse site effects during therapy noted. CONCLUSIONS: Within the limits of the study it can be concluded that photodynamic therapy with the use of Chlorine-e6 can lead to considerable reduction of oral leukoplakia lesions size thus may be useful in clinical practice. However there is a need of further studies on larger number of cases and longer follow-up time.

Biopolymeric film containing bioactive naphthoquinone (shikonin) in combined therapy of inflammatory destructive lesions in the buccal mucosa.

Clinical morphological efficiency of local application of a new biopolymeric film was studied. The film was based on methylcellulose derivatives and contained shikonin (preparation of plant origin) and its esters isolated from Lithospermum erythrorhizon L. cell culture. Combined therapy of 30 patients (34-72 years) with erosive ulcerative lichen planus and leukoplakia of the buccal mucosa was carried out. Local application of the new drug led to more rapid pain relief, epithelialization of the inflammatory destructive foci in the buccal mucosa, and reduced the intensity of morphological signs of lesions in the studied patient population.

Diet and risk of oral potentially malignant disorders in rural Sri Lanka.

BACKGROUND: While the protective role of antioxidant nutrients against cancer is well established, data on Asian diets in patients with oral cancer are meagre. METHODS: A total of 1029 subjects over 30 years of age were investigated on their dietary practices in the Sabaragamuwa province (Sri Lanka) in 2006-07. Data collection tools were an interviewer-administered questionnaire, a three-day food diary and an examination of the oral cavity. Subjects identified with Oral Potentially Malignant Disorders (OPMD) and disease-free controls were analysed in a case-control fashion. Among the OPMDs, those with leukoplakia were separately considered. A further subgroup analysis was undertaken for ß-carotene-rich foods. The analysis was stratified by portions of fruit/vegetables consumed as five or more portions and two or more portions daily. RESULTS: A low BMI (<18.5) was a significant independent risk factor for the development of OPMD. More than half of both cases and controls consumed less than two portions of fruit/vegetables per day and only 20 subjects consumed more than five portions per day. Intake of more than two portions per day of ß-carotene-containing fruits/vegetables significantly reduced the risk of having an OPMD and leukoplakia (OR = 0.5; 95% CI, 0.3-0.9). The significant differences observed with BMI and fruits/vegetables were attenuated when adjusted for betel quid chewing, smoking and alcohol use. CONCLUSIONS: This study discloses prevailing under-nutrition in this rural population with very low daily consumption of fruit/vegetables. Cancer preventive properties in their diets are limited and are swamped by the known carcinogenic agents associated with use of betel quid, tobacco and alcohol.

Induction of apoptosis and up-regulation of cellular proliferation in oral leukoplakia cell lines inside electric field.

OBJECTIVE: In dentistry, metallic alloys are used for dentures, restorative materials, and orthodontic devices. Electric voltages up to 950 mV may occur between different dental alloys in the oral cavity. This study aimed to investigate physiologic reactions of oral leukoplakia cells in vitro to electric fields. STUDY DESIGN: A human leukoplakia cell line (MSK-LEUK1), cultivated in keratinocyte growth medium (KGM-2) supplemented with growth factors in 5% CO(2) humidified air at 37°C, was exposed to electric field strength of 1-20 V/m for 24 hours in a custom-made pulse chamber. The cells were then analyzed for proliferation with the use of BrdU assay and for apoptosis with the use of TUNEL assay. Findings were assessed with the use of fluorescent microscopy. Ultrastructural changes were studied by transmission electron microscopy. RESULTS: Electric field strength of 1-10 V/m led to up-regulation of cell proliferation rate from 10.64% to 44.06% (P = .0001). The apoptotic index increased significantly (P = .0001) from 20.03% at 1 V/m to 46.56% at 10 V/m. Individual cell keratinization was seen in leukoplakia cells treated with 16 V/m. CONCLUSIONS: Oral galvanism induces subcellular changes in oral precancer cells in vitro that closely simulate some of the morphologic features of oral squamous cell carcinoma cells in vivo.