Targeting the genetic landscape of oral potentially malignant disorders has the potential as a preventative strategy in oral cancer.

This study reviews the molecular landscape of oral potentially malignant disorders (OPMD). We examine the impact of tumour heterogeneity, the spectrum of driver mutations (TP53, CDKN2A, TERT, NOTCH1, AJUBA, PIK3CA, CASP8) and gene transcription on tumour progression. We comment on how some of these mutations impact cellular senescence, field cancerization and cancer stem cells. We propose that OPMD can be monitored more closely and more dynamically through the use of liquid biopsies using an appropriate biomarker of transformation. We describe new gene interactions through the use of a systems biology approach and we highlight some of the first studies to identify functional genes using CRISPR-Cas9 technology. We believe that this information has translational implications for the use of re-purposed existing drugs and/or new drug development. Further, we argue that the use of digital technology encompassing clinical and laboratory-based data will create relevant datasets for machine learning/artificial intelligence. We believe that therapeutic intervention at an early molecular premalignant stage should be an important preventative strategy to inhibit the development of oral squamous cell carcinoma and that this approach is applicable to other aerodigestive tract cancers.

Non-invasive screening of a microRNA-based dysregulation signature in oral cancer and oral potentially malignant disorders.

INTRODUCTION: We have previously shown that oral swirls are a robust source of microRNA protected by extracellular vesicles, potentially useful to detect oral squamous cell carcinoma (OSCC)-associated molecular aberration. OBJECTIVES: To study a developed dysregulation score and risk classification algorithm based upon a panel of OSCC-associated microRNA in oral swirls from individuals with OSCC and oral potentially malignant disorders (OPMDs). MATERIALS AND METHODS: An OSCC-associated panel of 5 microRNAs (miR-24; miR-21; miR-99a; let-7c; miR-100;) was quantified by qPCR in 190 individuals with and without mucosal abnormalities, including OSCC (n = 53) and OPMDs (n = 74). Each sample was analyzed using a developed dysregulation score (dSCORE) and risk classification algorithm, allocating a LOW- or HIGH-RISK score. The influence of demographic, systemic, oral health and mucosal disease factors on the developed test was analyzed. RESULTS: MicroRNA for analysis can be predictably isolated from oral swirls sourced from individuals with a range of demographic, systemic and oral health findings. Utilizing the presence of HIGH-RISK identified OSCC patients with 86.8% sensitivity and 81.5% specificity. Older age and female gender were associated with higher dSCOREs and higher proportions of HIGH-RISK classification amongst individuals with no mucosal abnormalities. The dSCOREs for all subgroups of OPMDs were significantly different from the OSCC group. CONCLUSION: This is the first comparison of microRNA sourced from oral swirls from individuals with OPMDs with individuals with and without OSCC. A HIGH-RISK dysregulation signature was found to be accurate in indicating the presence of OSCC and exampled to parallel malignant transformation.

Predictive Prognostic Value of Tissue-Based MicroRNA Expression in Oral Squamous Cell Carcinoma: A Systematic Review and Meta-analysis.

Oral squamous cell carcinoma (OSCC) is a common type of cancer characterized by a low survival rate, mostly due to local recurrence and metastasis. In view of the importance of predicting tumor behavior in the choice of treatment strategies for OSCC, several studies have attempted to investigate the prognostic value of tissue biomarkers, including microRNA (miRNA). The purpose of this study was to perform a systematic review and meta-analysis to evaluate the relationship between miRNA expression and survival of OSCC patients. Studies were identified by searching on MEDLINE/PubMed, SCOPUS, Web of Science, and Google Scholar. Quality assessment of studies was performed with the Newcastle-Ottawa Scale. Data were collected from cohort studies comparing disease-free survival and overall survival in patients with high miRNA expression compared to those with low expression. A total of 15 studies featuring 1,200 OSCC samples, predominantly from Asia, met the inclusion criteria and were included in the meta-analysis. Poor prognosis correlated with upregulation of 9 miRNAs (miR-21, miR-455-5p, miiR-155-5p, miR-372, miR-373, miR-29b, miR-1246, miR-196a, and miR-181) and downregulation of 7 miRNAs (miR-204, miR-101, miR-32, miR-20a, miR-16, miR-17, and miR-125b). The pooled hazard ratio values (95% confidence interval) related to different miRNA expression for overall survival and disease-free survival were 2.65 (2.07-3.39) and 1.95 (1.28-2.98), respectively. The results of this meta-analysis revealed that the expression levels of specific miRNAs can robustly predict prognosis of OSCC patients.

Role of tissue-specific steroid metabolism in oral disease: Is there any clinical implication?

The discovery of an oral glucocorticoid system has provided novel conceptual frameworks for understanding the effects of endogenous and exogenous corticosteroids in the oral cavity. For example, liquorice derivatives have long been used in the treatment of oral inflammatory conditions and it is now known that a chief constituent of liquorice root, glycyrrhetinic acid, inhibits 11ß-hydroxysteroid dehydrogenase (11ß-HSD) type 2 thus increasing local cortisol levels. Hence, targeting the local interconversion between inactive cortisone and active cortisol by 11ß-HSD inhibitors/activators offers potentially advantageous strategies for the treatment of oral inflammatory and autoimmune conditions. The recent characterisation of a cancer-associated glucocorticoid system has further extended the implications of cortisol metabolism in oral disease. New evidence now questions the use of synthetic corticosteroids in patients with cancer and, possibly, in oral potentially malignant disorders. For example, cortisol production by cancer cells has been shown to inhibit tumour-specific CD8+ T cells, to promote migration and invasion and to induce chemoresistance in vitro. This viewpoint briefly summarises the recent evidence for a role of the local steroid metabolism in oral oncology and immunology and its potential clinical implications.

Diagnostic patterns and delays in autoimmune blistering diseases of the mouth: A cross-sectional study.

OBJECTIVES: To describe the natural history and factors influencing diagnostic delays among patients with autoimmune blistering diseases of the mouth. MATERIALS AND METHODS: In this cross-sectional study, 27 newly diagnosed patients were interviewed, and professional and patient delays were calculated. Disease extent and severity scores were determined using Saraswat scoring system. RESULTS: Twenty-seven patients were interviewed and examined. Patient delay was significantly longer in patients who had desquamative gingivitis as initial presentation, in those who tried to use home remedies and over the counter medications, and in patients with less severe disease. Most patients (n = 21 [77.7%]) made more than one consultation, and the mean time needed to reach a definitive diagnosis (i.e. professional delay) was 83.2 ± 21.4 days (range from 21 to 130 days). Professional delay was significantly correlated with the number of previous consultations (r = .78) and was significantly longer in patients who had desquamative gingivitis as initial presentation. CONCLUSION: Diagnosis of oral blistering diseases is often delayed. Diagnostic delay is more common in patients presenting with desquamative gingivitis and those with less severe disease. Improving patients and healthcare professionals' awareness about oral blistering diseases might help reduce diagnostic delay.

Desmosomes in disease: a guide for clinicians.

The large number of diseases occurring when desmosome constituents are impaired provides striking evidence for the key role of desmosomes in maintaining tissue integrity. A detailed understanding of the molecular alterations causing desmosomal dysfunction has, in turn, underpinned the development of novel diagnostic tools. This has salient clinical implications for dentists and oral medicine practitioners because the majority of desmosomal diseases affect the oral cavity. In the present article, we review the autoimmune, infectious, genetic, and neoplastic diseases that target the desmosome, with particular emphasis on clinical manifestations, diagnostic pathways, and relevant laboratory investigations.

Oral swirl samples - a robust source of microRNA protected by extracellular vesicles.

BACKGROUND: MicroRNAs are small non-coding RNAs which are dysregulated in disease states, such as oral cancer. Extracellular vesicles, a potential source of microRNA, are found in saliva. OBJECTIVE: To demonstrate that a quantifiable amount of microRNA can be isolated from oral swirl samples. Additionally, we hypothesized that extracellular vesicles may protect contained microRNA from degradation in these samples. METHOD: A polyethylene glycol-based precipitation was used for extracellular vesicle enrichment of oral swirl samples. Comparison was made between samples treated with and without RNase. Further, samples from three subjects were exposed to a range of conditions over 7 days and assessed for presence of microRNA by reverse-transcription quantitative PCR. Extracellular vesicles from samples were identified under transmission electron microscopy. RESULTS: An adequate quantity of microRNA for qPCR analysis was extractable from samples despite exposure to conditions under which degradation of RNA would be expected. CONCLUSION: A technique was developed to isolate an adequate quantity of microRNA for analysis from oral swirl samples. Extracellular vesicle-associated microRNA may be protected from degradation. This technique moves towards chairside application of translational microRNA research in the field of oral cancer prognostics.

Cancer-associated fibroblasts regulate keratinocyte cell-cell adhesion via TGF-ß-dependent pathways in genotype-specific oral cancer.

The interrelationship between malignant epithelium and the underlying stroma is of fundamental importance in tumour development and progression. In the present study, we used cancer-associated fibroblasts (CAFs) derived from genetically unstable oral squamous cell carcinomas (GU-OSCC), tumours that are characterized by the loss of genes such as TP53 and p16INK4A and with extensive loss of heterozygosity, together with CAFs from their more genetically stable (GS) counterparts that have wild-type TP53 and p16INK4A and minimal loss of heterozygosity (GS-OSCC). Using a systems biology approach to interpret the genome-wide transcriptional profile of the CAFs, we show that transforming growth factor-ß (TGF-ß) family members not only had biological relevance in silico but also distinguished GU-OSCC-derived CAFs from GS-OSCC CAFs and fibroblasts from normal oral mucosa. In view of the close association between TGF-ß family members, we examined the expression of TGF-ß1 and TGF-ß2 in the different fibroblast subtypes and showed increased levels of active TGF-ß1 and TGF-ß2 in CAFs from GU-OSCC. CAFs from GU-OSCC, but not GS-OSCC or normal fibroblasts, induced epithelial-mesenchymal transition and down-regulated a broad spectrum of cell adhesion molecules resulting in epithelial dis-cohesion and invasion of target keratinocytes in vitro in a TGF-ß-dependent manner. The results demonstrate that the TGF-ß family of cytokines secreted by CAFs derived from genotype-specific oral cancer (GU-OSCC) promote, at least in part, the malignant phenotype by weakening intercellular epithelial adhesion.

Fibroblast activation and senescence in oral cancer.

There is now compelling evidence that the tumour stroma plays an important role in the pathogenesis of cancers of epithelial origin. The pre-eminent cell type of the stroma is carcinoma-associated fibroblasts. These cells demonstrate remarkable heterogeneity with activation and senescence being common stress responses. In this review, we summarise the part that these cells play in cancer, particularly oral cancer, and present evidence to show that activation and senescence reflect a unified programme of fibroblast differentiation. We report advances concerning the senescent fibroblast metabolome, mechanisms of gene regulation in these cells and ways in which epithelial cell adhesion is dysregulated by the fibroblast secretome. We suggest that the identification of fibroblast stress responses may be a valuable diagnostic tool in the determination of tumour behaviour and patient outcome. Further, the fact that stromal fibroblasts are a genetically stable diploid cell population suggests that they may be ideal therapeutic targets and early work in this context is encouraging.

Senescent cancer-associated fibroblasts secrete active MMP-2 that promotes keratinocyte dis-cohesion and invasion.

BACKGROUND: Previous studies have demonstrated that senescent cancer-associated fibroblasts (CAFs) derived from genetically unstable oral squamous cell carcinomas (GU-OSCC), unlike non-senescent CAFs from genetically stable carcinomas (GS-OSCC), promoted keratinocyte invasion in vitro in a paracrine manner. The mechanism by which this occurs is unclear. METHODS: Previous work to characterise the senescent-associated secretory phenotype (SASP) has used antibody arrays, technology that is limited by the availability of suitable antibodies. To extend this work in an unbiased manner, we used 2D gel electrophoresis and mass spectroscopy for protein identification. Matrix metalloproteinases (MMPs) were investigated by gelatin zymography and western blotting. Neutralising antibodies were used to block key molecules in the functional assays of keratinocyte adhesion and invasion. RESULTS: Among a variety of proteins that were differentially expressed between CAFs from GU-OSCC and GS-OSCC, MMP-2 was a major constituent of senescent CAF-CM derived from GU-OSCC. The presence of active MMP-2 was confirmed by gelatine zymography. MMP-2 derived from senescent CAF-CM induced keratinocyte dis-cohesion and epithelial invasion into collagen gels in a TGF-ß-dependent manner. CONCLUSIONS: Senescent CAFs from GU-OSCC promote a more aggressive oral cancer phenotype by production of active MMP-2, disruption of epithelial adhesion and induction of keratinocyte invasion.

Unexpected resilience to experimental gingivitis of subepithelial connective tissue grafts in gingival recession defects: a clinical-molecular evaluation.

BACKGROUND AND OBJECTIVE: The subepithelial connective tissue graft (SCTG) is the most widely used procedure for the treatment of gingival recession defects. Little is known, however, as to whether the apposed gingival flaps are more predisposed to develop plaque-related inflammation compared to healthy sites. This has salient clinical implications, as the long-term results of root coverage will depend largely on the level of inflammation of the grafted tissue. METHODS: In the present split-mouth case-control study, clinical and biomolecular parameters were used to assess the level of inflammation of periodontal sites 12 mo after treatment with SCTG (test) and healthy non-treated gingivae (control) following the induction of plaque-related gingivitis in 19 patients. RESULTS: The data showed that test sites had a significantly (P < 0.05) lower gingival index and angulated bleeding score compared to control sites (gingival index = 1.05 ± 0.23 vs. 1.34 ± 0.47; angulated bleeding score = 0.34 ± 0.37 vs. 0.61 ± 0.39) after induction of experimental gingivitis, whereas the plaque index did not differ in the two groups (P > 0.05). With regard to the biomolecular parameters, baseline levels of the proinflammatory cytokine interleukin-1ß were higher in the gingival crevicular fluid of test sites. However, control sites exhibited more pronounced increase in the levels of interleukin-1ß compared to test sites, upon plaque accumulation, so that the final concentration was similar in both groups. No changes were recorded in the gingival crevicular fluid volume. CONCLUSION: Analysis of the data demonstrates that the sites of gingival recession treated with SCTG develop a lower degree of plaque-induced inflammation compared to healthy gingivae. This strongly suggests that SCTG does not predispose to inflammation and to further gingival recession and makes it a safe technique in the treatment of gingival defects.

Molecular insights into the effects of sodium hyaluronate preparations in keratinocytes.

BACKGROUND: Hyaluronic acid (HA) preparations are widely used in clinical practice to accelerate wound healing, but it is not clear whether HA can exert direct effects on epidermal keratinocytes. AIM: To investigate the molecular and functional changes induced by HA preparations in keratinocytes by measuring global gene expression and wound healing. METHODS: Human skin keratinocytes were used for this study. They were treated with either sodium hyaluronate (SH) alone or a commercial adjuvant gel (Aminogam(®)) containing SH in combination with a pool of synthetic amino acids (L-proline, L-leucine, L-lysine and glycine). Global gene expression of nearly 55,000 transcripts was investigated with a chip array (Affymetrix Human Genome U133 2.0 Plus). RESULTS: We found that keratinocytes expressed all major HA receptors at the transcriptional level. In a fibroblast-free system, both SH and the adjuvant gel could effectively promote wound healing of keratinocytes. Major gene expression changes induced by HA preparations involves proteolysis, proteinase inhibitors, cellular metabolism and cytoskeleton. In total, 21 genes were differentially transcribed by SH and the adjuvant gel. CONCLUSIONS: Keratinocytes represent a previously underestimated target for HA action in wound healing. HA preparations induce transcriptional changes in keratinocytes and stimulate wound closure. Furthermore, the addition of synthetic amino acids to SH induces a distinct transcriptional profile.

Urban legends: pemphigus vulgaris.

Pemphigus vulgaris (PV) is the most common type of pemphigus. PV pathogenesis is still debated, and treatment remains challenging. We investigated five controversial topics: (1) What are the target antigens in PV? (2) Do desmogleins adequately address PV pathophysiology? (3) How does acantholysis occur in PV? (4) Is PV still a lethal disease? (5) What is the role of rituximab (RTX) in PV treatment? Results from extensive literature searches suggested the following: (1) Target antigens of PV include a variety of molecules and receptors that are not physically compartmentalized within the epidermis. (2) PV is caused by a variety of autoantibodies to keratinocyte self-antigens, which concur to cause blistering by acting synergistically. (3) The concept of apoptolysis distinguishes the unique mechanism of autoantibody-induced keratinocyte damage in PV from other known forms of cell death. (4) PV remains potentially life-threatening largely because of treatment side effects, but it is uncertain which therapies carry the highest likelihood of lethal risk. (5) RTX is a very promising treatment option in patients with widespread recalcitrant or life-threatening PV. RTX's cost is an issue, its long-term side effects are still unknown, and randomized controlled trials are needed to establish the optimal dosing regimen.

Characterization of a novel oral glucocorticoid system and its possible role in disease.

Synthetic corticosteroids are used widely for the treatment of a variety of diseases of the mouth. However, little is known as to whether the oral mucosa is able to modulate the local concentration of active corticosteroids or to produce steroids de novo. This has important clinical implications, because tissue-specific regulation of glucocorticoids is a key determinant of the clinical efficacy of these drugs. In the present study, we show that oral fibroblasts and keratinocytes expressed ACTH receptor (MC2R), glucocorticoid receptor (GR), and 11ß-hydroxysteroid dehydrogenases (11ß-HSDs). Unlike keratinocytes, fibroblasts lacked 11ß-HSD2 and could not effectively deactivate exogenously administered cortisol. However, both cell types were able not only to activate cortisone into the active form cortisol, but also to synthesize cortisol de novo following stimulation with ACTH. 11ß-HSD2, the enzyme controlling cortisol deactivation, exhibited different patterns of expression in normal (squamous epithelium and salivary glands) and diseased oral mucosa (squamous cell carcinoma and mucoepidermoid carcinoma). Blocking of endogenous cortisol catabolism in keratinocytes with the 11ß-HSD2 inhibitor 18ß-glycyrrhetinic acid mimicked the effect of exogenous administration of hydrocortisone and partially prevented the detrimental effects induced by pemphigus vulgaris sera. Analysis of the data demonstrates that a novel, non-adrenal glucocorticoid system is present in the oral mucosa that may play an important role in disease.

Deregulation of PERK in the autoimmune disease pemphigus vulgaris occurs via IgG-independent mechanisms.

BACKGROUND: Serum and IgG isolated from patients with the autoimmune blistering disease pemphigus vulgaris (PV) trigger complex intracellular pathways in keratinocytes, including alterations of the cell cycle and metabolism, which ultimately lead to cell-cell detachment (acantholysis). We have shown previously that one of the earliest pathogenic events in PV is the activation of protein kinases, including the PKR-like endoplasmic reticulum (ER) kinase PERK. OBJECTIVES: In the present study we investigated in more detail the role of PERK in the pathogenesis of PV. METHODS: PERK levels were assessed by Western blotting and in-cell enzyme-linked immunosorbent assay, and PERK expression was silenced by siRNA technology. The effects of PV sera/IgG on keratinocyte cultures were investigated by flow cytometry, MTT and adhesion assays. RESULTS: We show that PERK is activated in keratinocytes exposed to PV serum, as demonstrated by an increase in phosphorylated PERK levels and phosphorylation of eIF2α. Decreased expression of PERK by siRNA reduced the effects of PV serum on the cell cycle and keratinocyte viability, two key events in PV pathophysiology. As impairment of metabolic activity in PV is partially due to non-IgG serum factors, we then investigated the activation of PERK in keratinocytes incubated with whole PV serum, purified PV IgG and IgG-depleted PV serum. The data demonstrated that PV sera depleted of IgG, but not PV IgG, triggered PERK phosphorylation and this correlated with a marked reduction of metabolic activity in keratinocytes exposed to IgG-free serum. Knockdown of PERK by siRNA abrogated the changes in the cell cycle and apoptosis induced by IgG-depleted PV serum. Finally, the reduction of metabolic activity observed in keratinocytes exposed to IgG-depleted PV serum was almost absent in PERK-deficient cells. CONCLUSIONS: Taken together, the results demonstrate that activation of PERK participates in the reduction of metabolic activity and cell viability seen in PV and that this phenomenon depends on non-IgG factors. PERK activation may represent a novel signalling mechanism linking ER stress and acantholysis in PV.

Controversial role of antibodies against linear epitopes of desmoglein 3 in pemphigus vulgaris, as revealed by semiquantitative living cell immunofluorescence microscopy and in-cell ELISA.

A novel explanation of pemphigus vulgaris (PV) pathogenesis suggests that serum autoantibodies may affect desmoglein 3 (Dsg3)-mediated adhesion by triggering depletion of Dsg3 from desmosomes. Furthermore, abrogation of Dsg3 from the cell seems to depend on anti-Dsg3 pemphigus IgG. In this study we sought to gain more insights into the role of PV IgG recognizing non-conformational epitopes of Dsg3 (anti-Dsg3-L IgG) by semi-quantitative living cell immunofluorescence (LCIF) microscopy, in-cell ELISA and morphometric analysis of acantholysis. Our data demonstrate that PV serum and PV IgG can induce acantholysis and reduce the total amount of Dsg3 in cultured keratinocytes, whereas anti-Dsg3-L IgG fail to do so when administered at concentrations comparable to those present in pathogenic PV sera. However, the Dsg3-depleting activity of such polyclonal anti-Dsg3 IgG was acquired when used at 1 microg/ml. Interestingly, both PV sera and IgG, including anti-Dsg3-L IgG, caused early depletion of surface Dsg3 while slightly affecting the total cell content of Dsg3 until late acantholysis. This raises a possibility that depletion of Dsg3 from cell membrane and reduction of the total cellular levels of Dsg3 represent distinct phenomena in PV acantholysis. Taken together, our data demonstrate that anti-Dsg3 PV IgG against linear epitopes of Dsg3 can induce acantholytic changes of keratinocytes in a dose- and time-dependent manner. Specifically, both morphological and biochemical changes suggestive of acantholysis are seen only at high IgG concentrations. We conclude that anti-Dsg3L IgG play a minor role in experimental PV under physiologic conditions.

Pilot study on recurrent aphthous stomatitis (RAS): a randomized placebo-controlled trial for the comparative therapeutic effects of systemic prednisone and systemic montelukast in subjects unresponsive to topical therapy.

BACKGROUND: Recurrent aphthous stomatitis (RAS) is characterized by recurrent painful oral ulcers whose etiology remains largely unknown. Numerous therapeutic protocols have been tried so far, but effectiveness remains an issue. OBJECTIVE: To test a new drug for patients with recurrent oral aphthae nonresponsive to local corticosteroid therapy, we compared the therapeutic effectiveness and adverse effects of systemic prednisone and systemic montelukast in a placebo-controlled trial. STUDY DESIGN: Sixty patients suffering from minor RAS for > or =6 months were studied and randomly assigned to 3 groups of 20 each in a double-blind study. Patients of group A took 25 mg prednisone orally daily for 15 days, 12.5 mg daily for 15 days, 6.25 mg daily for 15 days, then 6.25 mg on alternate days for 15 days. Patients of group B took 10 mg montelukast orally every evening and then on alternate days for the second month. Patients of group C took 100 mg cellulose (placebo) by mouth daily for the first month and on alternate days for the second month. Outcomes assessed were days til pain cessation, days to ulcer healing, and number of aphthae occurring during the follow-up period. RESULTS: Both prednisone and montelukast were effective in reducing the number of lesions and improving pain relief and ulcer healing when compared with placebo. Prednisone was more effective than montelukast in pain cessation (P < .0001) and in accelerating ulcer healing (P < .0001). However, adverse drug reactions recorded during the entire trial were more common in the prednisone group compared with montelukast (10%) and placebo (10%). CONCLUSIONS: These data suggest that the effectiveness of systemic montelukast is similar to that of systemic prednisone in patients with RAS. The lack of serious side effects makes montelukast a candidate drug to use in cases of RAS where pharmacologic therapy for long periods is needed.

Serum of patients with oral pemphigus vulgaris impairs keratinocyte wound repair in vitro: a time-lapse study on the efficacy of methylprednisolone and pyridostigmine bromide.

OBJECTIVES: Pemphigus vulgaris (PV) is an autoimmune blistering disease affecting primarily oral mucosa and skin. Among the drugs used for the therapy of pemphigus, both methylprednisolone (MP) and pyridostigmine bromide (PBr) can prevent acantholysis in vitro. However, their putative therapeutic properties in regenerating PV-like lesions and promoting the healing process still remain to be demonstrated. To address this issue, here we have developed a model for studying the process of epithelial cleft regeneration in PV by artificially wounding keratinocyte monolayers. MATERIALS AND METHODS: The experimental model was established by scratching confluent monolayers to simulate the epithelial cleft; then, wound regeneration in the presence of submaximal concentrations of PV sera was studied by time-lapse microscopy, with or without the addition of MP and PBr in the culture medium. RESULTS: Pemphigus vulgaris serum inhibited epithelial cleft repair of wounded monolayers. Indeed, in the presence of 10% (v/v) PV serum, keratinocytes reached only 2% confluence within 72 h vs an almost complete healing of controls. When administered together with PV sera, MP significantly (P < 0.01) enhanced wound fill by 30% after 72 h. PV-associated wound repair was significantly (P < 0.05) ameliorated by PBr by 24 h and keratinocytes reached 20% confluence after 72 h. Interestingly, neither MP nor PBr could accelerate wound healing when compared with untreated control monolayers. CONCLUSIONS: In PV, MP and PBr exert their curative effects in part by enhancing the regeneration properties of keratinocytes. Indeed, our data suggest that both drugs can specifically counterbalance the detrimental effects of PV serum on keratinocyte wound healing. These findings provide an explanation for the efficacy of MP and PBr in the treatment of PV lesions in human skin and oral mucosa.

Long-standing oral ulcers: proposal for a new 'S-C-D classification system'.

Persistent oral ulcers and erosions can be the final common manifestation, sometimes clinically indistinguishable, of a diverse spectrum of conditions ranging from traumatic lesions, infectious diseases, systemic and local immune-mediated lesions up to neoplasms. The process of making correct diagnosis for persistent oral ulcers still represents a challenge to clinicians. Major diagnostic criteria should include the clinical appearance of both ulcer and surrounding non-ulcerated mucosa, together with the evaluation of associated signs and symptoms, such as: number (single or multiple), shape, severity of the ulcer(s), conditions of remaining mucosa (white, red or with vesiculo-bullous lesions) and systemic involvement (e.g. fever, lymphadenopathy or evaluation of haematological changes). The aim of this paper was to review the literature relating to persistent oral ulcers and provide a helpful, clinical-based diagnostic tool for recognising long-standing ulcers in clinical dental practice. The authors, therefore, suggest distinguishing simple, complex and destroying (S-C-D system) ulcerations, as each requires different diagnostic evaluations and management. This classification has arisen from studying the current English literature relating to this topic, performed using MEDLINE / PubMed / Ovid databases.

At least three phosphorylation events induced by pemphigus vulgaris sera are pathogenically involved in keratinocyte acantholysis.

Intercellular adhesion among keratinocytes is guaranteed by desmosomes. Disruption of desmosomal integrity leads to cell-cell detachment or acantholysis, as it classically occurs in pemphigus vulgaris (PV), an autoimmune blistering disease of skin and mucous membranes. While purified PV IgG seems to trigger intracellular signaling that crucially involves p38 MAPK, keratinocyte acantholysis induced by whole PV serum may recruit a number of additional signals. In this study, the Pro-Q Diamond Phosphoprotein Assay was used to investigate the overall changes in protein phosphorylation levels in an in vitro model of PV. We showed that keratinocytes exposed to whole PV sera underwent at least three early and transient phosphorylation events. Two bands with apparent molecular masses of 35 and 45 kDa were found to be phosphorylated within 1 min after incubation with PV sera. A third band of about 80 kDa reached the peak of phosphorylation level after 3 hours. Morphologic evidence of cell shrinkage and acantholysis were late events and did not correlate temporally with kinase activation, suggesting that cytoskeleton reorganization is a downstream phenomenon. Interestingly, pharmacological abrogation of PV-specific protein phosphorylation was able to inhibit the cell-cell detachment, rounding up, and redistribution of Dsg3 in keratinocytes. Thus, at least three phosphorylation events are pathogenically involved in pemphigus acantholysis.