Mast cell density in oral submucous fibrosis: a possible role in pathogenesis

Enzyme-linked immunosorbent assay and immunohistochemical analysis of mast cell related biochemicals in oral submucous fibrosis

Oral submucous fibrosis (OSMF), a potentially malignant disorder, is developed by progressive fibrous tissue deposition in connective tissue along with atrophy of oral mucosa. Histological sections also show the mast cell infiltration in submucosa which may indicate their possible role in this entity. Abundant availability of biochemicals in mast cells like histamine and serine proteases like chymase may be released and play specific pathways in the disease pathophysiology. Possibly, if the histamine release has some part to play, diamine oxidase may also be found to have a relationship as it metabolizes histamine. The present study is proposed to identify the presence of chymase, histamine, and diamine oxidase in both, serum as well as tissue by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) respectively. This study may provide probable insight into the mast cell-related chemicals and their association with OSMF.

Differential expression of cancer stem cell markers and pro-inflammatory cytokine IL-1β in the oral squamous cell carcinoma and oral submucosal fibrosis

Objectives

The poor prognosis of oral squamous cell carcinoma (OSCC) is vastly due to late diagnosis. The oral submucosal fibrosis (OSMF) is often unnoticed pathology linked with high risk of malignancy. Recently, we demonstrated that the clinicopathological alterations in OSMF and OSCC patients were correlated with cancer stem cell (CSCs) markers (CD133 and CD44). However, the parallel alterations of interleukin-1 beta (IL-1β) with CSCs expression are largely unexplored. Thus, we aimed to investigate the relationship between IL-1β alterations and CSC marker expression in both OSMF and OSCC situations.

Materials and Methods

A total of 135 people have signed up for the study. There were sixty each in OSMF and OSCC groups, as well as 15 healthy controls. Levels of serum IL-1β were examined by ELISA. Immunohistochemistry (IHC) was used to examine the expression of CD133 and CD44. For evaluating differential CSCs expression, IHC scoring (0-4) was utilized.

Results

The IHC results showed maximum subjects in the OSMF and OSCC displaying CD44 and CD133 positivity, although the extent of expression in terms of IHC scoring found variable. CD133 and CD44-positive subjects showed increased levels of IL-1β in the OSMF and OSCC group. Nevertheless, the enhancement of IL-1β is more pronounced in the OSCC cases. Further, we observed a direct link of IL-1β levels with IHC scoring. Multivariate regression analysis demonstrated a significant role for CD44 and CD133 positivity in the increase of IL-1β levels.

Conclusion

We concluded that concurrent simultaneous changes in CSC biomarkers and IL-1β may help with early detection of OSMF and OSCC conditions.

Mast cell expression in oral submucous fibrosis: A systematic review and metanalysis

BACKGROUND

Oral submucous fibrosis (OSMF) is a chronic disorder associated with reduced mouth opening, burning sensation and listed as potentially malignant disorder. The role of mast cells in initiation and progression of this condition has been debated in last few years. It is imperative to understand the definitive role of mast cells and subsequently identify a possible cost-efficient treatment modality for OSMF. This review aimed to study the role of mast cells in OSMF by framing a research question that assessed the mast cell count (MCC), their degranulation and immunohistochemical analyses. We performed a comprehensive search of PubMed, EBSCOhost and general Google search that conceded 26 studies from which 15 articles were finalized for the review. The individual study syntheses revealed increased MCC in OSMF as compared to controls. Also, there was decreased MCC with the progression of OSMF. However, the metanalysis showed high level of heterogeneity as three studies out of eight studies found reduced MCC in disease when compared with controls. There is definite increase in mast cell in OSMF although the cell count falls with the advancement of OSMF. This increases the scope for further research to identify exact mechanism by which mast cells contribute to fibrosis and conduct the drug trials that can inhibit the mechanism. Key words:Oral submucous fibrosis, mast cell count, degranulated mast cells, stages of OSMF.Oral submucous fibrosis, mast cell count, degranulated mast cells, stages of OSMF.

The Immunolocalization of Mast Cells in the Pathology of Oral Submucous Fibrosis

Background Oral submucous fibrosis (OSMF) is a prevalent precancerous condition of the oral cavity and an ambiguity to clinicians because of its indistinguishable etiopathogenesis. Previous studies could not establish a definite role of mast cells (MCs) in the fibrosis of stroma. The present study was done to study the histopathological changes in OSMF and to determine the association of mast cells (MCs) and their degranulated components with vascularity. Methods A retrospective case-control study involved 40 cases of various histopathological grades of OSMF and was compared with 10 cases of normal buccal mucosa by using a cluster of differentiation 117 (CD117) kit for the identification of MCs and Masson's trichrome stain to study the number of blood vessels (BVs). Results The present study indicated that advanced cases of OSMF had keratinized epithelium with atrophic changes and moderate to advanced fibrosis of stroma with the involvement of underlying muscles. The MC density and the number of blood vessels were progressively reduced in OSMF as the grade advanced compared to healthy controls. Conclusion An increase in the mast cell density in the initial stages of OSMF suggests their definite role in the initiation of fibrosis and secondary changes to the epithelium such as atrophy.

The Antifibrotic and the Anticarcinogenic Activity of Capsaicin in Hot Chili Pepper in Relation to Oral Submucous Fibrosis

A burning sensation on eating spicy foods purportedly supports the role of capsaicin, an active component of chili peppers, in the etiology of oral submucous fibrosis (OSF). Although the mast cell mediators and activated P2X receptors induce a constant burning sensation through an ATP-dependent mechanism, it is the activation of the transient receptor potential vanilloid 1 (TRPV-1) receptor by capsaicin that aggravates it. The molecular basis for the burning pain in OSF is thus attributable to the activation of TRPV1. There is overwhelming evidence that confirms capsaicin has more of a protective role in attenuating fibrosis and is potentially therapeutic in reversing conditions linked to collagen accumulation. The activation of TRPV-1 by capsaicin increases intracellular calcium ([Ca²⁺]_i), upregulates AMP-activated protein kinase (AMPK) and Sirtuin-1 (SIRT-1), to enrich endothelium-dependent vasodilation via endothelial nitric oxide synthase (eNOS). The induction of vasodilation induces antifibrotic effects by alleviating hypoxia. The antifibrotic effects of capsaicin are mediated through the upregulation of antioxidant enzymes, downregulation of inflammatory genes and suppression of new collagen fibril formation. Capsaicin also demonstrates an anticarcinogenic effect by upregulating the cytotoxic T cells and downregulating regulatory T cells through the inhibition of angiogenesis and promotion of apoptosis. Judicious administration of capsaicin with an appropriate delivery mechanism may have therapeutic benefits in reducing pain sensation, rendering antifibrotic effects, and preventing the malignant transformation of OSF. This paper provides an overview of the molecular basis of capsaicin and its therapeutic application as an antifibrotic and anticarcinogenic agent for the treatment of OSF.

Correlation of Clinical Features in Oral Submucous Fibrosis: A 9-Year Retrospective Study

BACKGROUND

Oral Submucous Fibrosis is a chronic debilitating disease and potentially malignant disorder of the oral cavity known in medical literature for a long time. The study aims to correlate the clinical staging of Oral Submucous Fibrosis with various clinical findings of the oral mucosa like hyperpigmentation, erosions, ulcerations, VAS score, tongue protrusion, and cheek flexibility.

METHODS

A retrospective observational study was undertaken and records of 1267 clinically diagnosed cases of OSMF were included in the study. Clinical grading was done as per criteria by Lai DR et al. The observations were tabulated and subjected to statistical analysis using SPSS software.

RESULTS

In our study, the incidence of hyperpigmentation, erosions, and ulcerations was higher in Group C OSMF. Visual analog scores in the range of 5-6 was noted in 40.9% of the total subjects, out of which 36.2% belonged to Group C OSMF. Tongue protrusion of less than 25 mm was seen in 10.65% of the subjects. Cheek flexibility of less than 0.6 cm was seen in 19.62% of the subjects, most of which belonged to Group D.

CONCLUSION

In our study, we found an increase in the occurrence and severity of symptoms with an increase in grades of OSMF, but this increase was not observed to be consistent. Hence classification based on a single clinical entity cannot be sufficient and correlations to other clinical findings should be studied over a large population and a multi-tier classification could be proposed in the future.

Evaluation of Mast Cells in Oral Potentially Malignant Disorders and Oral Squamous Cell Carcinoma

Background

Oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs) are epithelial-derived pathologies which share inflammation as a common initial pathogenic-inducing state. Mast cell is a key immune modulating cell which is primarily involved in initiation and propagation of inflammation. The role of mast cell in OPMDs and OSCC has been an established fact; however, its definitive pathogenic correlation is still under study. The objective of the study was to evaluate the number of mast cell in OPMDs and OSCC using special stain correlating its probable role as a promoter or retarder of OSCC.

Materials and Methods

Forty-five archival histopathologically confirmed cases each of OPMD and OSCC were studied for mast cells using toluidine blue and Alcian blue-safranin stain and compared with 10 normal oral mucosal tissues. Comparisons between the mast cells count was also performed between the two special stains.

Results

Among 100 cases, 67% were males and 33% were females. The mean age was 41.68 ± 13.39; 55.06 ± 12.55; and 18.4 ± 2.54 years for OPMDs, OSCC, and normal, respectively. A statistically significant increase in mast cells among OPMDs (9.88 ± 7.9) and OSCC (6.711 ± 3.94) was observed compared to normal oral mucosa. The mast cell count reduced among OSCC in comparison to OPMDs which was significant as well. The mean mast cell count for Alcian blue-safranin stain was higher than toluidine blue stain.

Conclusion

There is a decrease in mean mast cell count from OPMDs to OSCC which is suggestive of protective role of mast cell. Proper quantification of mast cells using specific stains can guide to define prognosis in oral potentially malignant disorders and oral cancer.

Immunopathogenesis of oral submucous fibrosis by chewing the areca nut

Oral submucous fibrosis (OSF) is a chronic, progressive, scarring, and premalignant disease of the oral mucosa. Its pathogenic factors are complex and include chewing areca nuts or other spicy food items, nutrition, and genetic and immune factors. Recently, immune factors have become the focus of medical research, with increased attention being paid to the role of immune regulation in diseases, particularly tumors. OSF is accompanied by obvious changes in the immune microenvironment. The aim of this review is to discuss the potential relationship of OSF and areca nuts genetic with the immune system, including lymphocytes, macrophage, Langerhans cell, mast cell, and substances released by activated immune cells, to determine the pathogenesis and treatment of OSF from an immunologic viewpoint.

Evaluation of mast cells and burning sensation in various stages of Oral Submucous Fibrosis

Background

Oral Submucous Fibrosis (OSMF) is a potentially malignant disorder and burning sensation is the initial complaint among these patients. Scientific literature has established that mast cells play a major role in various inflammatory disorders. However, OSMF being an inflammatory disorder, the role of mast cells is yet to be established. Hence the aim of this study was to evaluate mast cells and burning sensation in various stages of Oral Submucous Fibrosis.

Methods

The study population comprised of forty subjects, thirty were clinically confirmed cases of OSMF and ten healthy individuals served as control. A complete history and clinical examination followed by an incisional biopsy was performed. Samples obtained were subjected to routine histopathological examination and mast cells evaluation.

Results

Mean number of total mast cells in Stage I, II and III OSMF were 8.5 ± 0.7, 11.31 ± 8.8 and 24.7 ± 21.2 respectively. There was a significant difference in total mast cell count between cases and controls. Degranulated mast cells was a significant predictor (p = 0.028), indicating role in clinical staging of OSMF. Degranulated mast cells had a significant role and was a positive predictor (B = 0.763, OR 2.145[95%CI 1.055-4.630]) at moderate levels of burning sensation. A significant difference (p = 0.029) in burning sensation across histopathological grades was also observed in the study.

Conclusion

Degranulated mast cells were found to have a significant influence in mild to moderate levels of burning sensation among OSMF patients. Role of degranulated mast cells were also found to be significant in various clinical stages of OSMF.

Comparison of histochemical staining techniques for detecting mast cells in oral lesions

Mast cells are large cells with granular cytoplasm that participate in wound healing, angiogenesis and defense against pathogens. They also contribute to inflammation by initiating innate and acquired immunity. The granules of these cells exhibit characteristic staining properties. We investigated toluidine blue, astra blue, Alcian blue-pyronin Y and May-Grunwald Giemsa stains for mast cells in various oral lesions and assessed the efficacy of each for identifying mast cells. Sections were obtained from 10 each of diagnosed cases of inflammatory fibrous hyperplasia, periapical cyst, mild dysplasia, oral submucous fibrosis and oral squamous cell carcinoma and stained using the stains listed above. Mast cells were assessed for their presence, contrast of the mast cell in the connective tissue background and number. We found that May-Grunwald Giemsa stain was the best for identification of mast cells, although toluidine blue staining is less time-consuming. Overall we obtained better results using May-Grunwald Giemsa and toluidine blue for staining mast cells.

Expression and clinical significance of periostin in oral lichen planus

Oral lichen planus (OLP) is a chronic inflammatory lesion involving the oral mucosa, which has a high likelihood of progressing to cancer. The present study investigated the periostin expression in the mucosa and serum of patients with OLP and its correlation with serum cytokines. A total of 117 patients with OLP and 110 healthy controls were included in the study. The protein expression of periostin were measured in the OLP and normal oral mucosa by immunohistochemistry. ELISA was performed to measure the serum levels of periostin, tumour necrosis factor-α (TNF-α), interleukin (IL)-6, interferon-γ (IFN-γ), IL-4 and thymic stromal lymphopoietin (TSLP). Compared with the control group the OLP group had a significantly increased number of cases with high periostin expression in the oral mucosa and a significantly increased serum periostin level (P<0.05). Among all 117 OLP subjects, high periostin expression was associated with higher serum IL-6, TNF-α, TSLP and tissue mast cell density. High periostin expression was also significantly associated with a lower IFN-γ/IL-4 ratio (P<0.05). The present study concluded that periostin expression was increased in the oral mucosa and serum of patients with OLP and was associated with inflammatory response, T helper 2 cytokine-predominant immune imbalance, increased mast cell count and TSLP. The modulation of periostin may represent an attractive novel therapeutic target.

Microenvironmental regulation of the progression of oral potentially malignant disorders towards malignancy

Oral potentially malignant disorders (OPMD) develop in a complex tissue microenvironment where they grow sustainably, acquiring oral squamous cell carcinoma (OSCC) characteristics. The malignant tumor depends on interactions with the surrounding microenvironment to achieve loco-regional invasion and distant metastases. Unlike abnormal cells, the multiple cell types in the tissue microenvironment are relatively stable at the genomic level and, thus, become therapeutic targets with lower risk of resistance, decreasing the risk of OPMD acquiring cancer characteristics and carcinoma recurrence. However, deciding how to disrupt the OPMD and OSCC microenvironments is itself a daunting challenge, since their microenvironments present opposite capacities, resulting in diverse consequences. Furthermore, recent studies revealed that tumor-associated immune cells also participate in the process of differentiation from OPMD to OSCC, suggesting that reeducating stromal cells may be a new strategy to prevent OPMD from acquiring OSCC characteristics and to treat OSCC. In this review, we discuss the characteristics of the microenvironment of OPMD and OSCC as well as new therapeutic strategies.

The role of mast cells in oral squamous cell carcinoma

The mast cells are initial effective lineage in both humoral and adaptive immunity. They are ubiquitous in skin, mucosa, and in function. They contain biologically essential and dynamic mediators in healthy and harmful conditions of tissue. Mast cell malfunctioning could be attributed to various chronic allergic diseases. Considerately, emerging evidence of mast cell involvement in various cancers shows them to have both positive and negative roles in tumour growth. It mostly indulges in tumour progression and metastasis via angiogenesis, extracellular matrix degradation, and mitogenic activity in the tumour microenvironment. The current paper reviewed research papers on mast cells in oral squamous cell carcinoma through the PubMed database from 1980 to the present date. The present paper is an attempt to summarise the research reports on the role of mast cells in oral squamous cell carcinoma. Further to this note, this paper also outlines the role of mast cells in normal physiological processes and tumour biology.

Malignant transformation of oral submucous fibrosis: overview of histopathological aspects

Oral submucous fibrosis (OSF), first described in 1952, is a potentially malignant disorder associated with betel quid and areca nut chewing, mostly prevalent in the population of the Indian subcontinent and South East Asia. Malignant transformation of OSF to squamous cell carcinoma (SCC) has been estimated to be between 2% and 8%. Our study aimed to review the histopathologic changes that contribute to the understanding of the malignant transformation of OSF. Changes in epithelial thickness and dysplasia characterized by micronuclei, altered AgNOR counts and distribution, keratin protein alteration, and alteration of P63 and E-cadherin characterize the epithelial changes during the transformation of OSF to SCC. Common mechanisms have been proposed to be involved in OSF and SCC, through collagen maturation and their interaction with myofibroblasts and mast cells. Fibrosis-driven vascular constriction that results in epithelial hypoxia has also been proposed as an important mechanism for the malignant transformation of OSF. However, reassessment of the classical view is required, because with demonstration of large blood vasculature in the connective tissue stroma of OSF, the hypothesis associated with tissue hypoxia-induced malignant transformation of OSF can be questioned.

Altered immunohistochemical expression of mast cell tryptase and chymase in the pathogenesis of oral submucous fibrosis and malignant transformation of the overlying epithelium

Mast cells (MCs) expressing serine proteases; tryptase and chymase, are associated with fibrosis in various diseases. However, little is known about their involvement in oral submucous fibrosis (OSF). Our goal was to evaluate the role of MC tryptase and chymase in the pathogenesis of OSF and its malignant transformation. Immunohistochemical expression of MC tryptase and chymase was evaluated in 20 cases of OSF, 10 cases of oral squamous cell carcinoma (OSCC) and 10 cases of healthy controls. Subepithelial zone of Stage 1 and 2 while deep zone of Stage 3 and 4 OSF demonstrated increased tryptase positive MCs. OSCC revealed a proportionate increase in tryptase and chymase positive MCs irrespective of areas of distribution. An altered balance in the subepithelial and deep distribution of tryptase and chymase positive MCs play an important role in the pathogenesis of OSF and its malignant transformation.