The master switch: Comparative study of mast cell in oral epithelial dysplasia, oral submucous fibrosis and oral squamous cells carcinoma and their association with inflammation and angiogenesis

Role of mast cells in the pathogenesis of oral submucous fibrosis: a systematic review and meta-analysis

BACKGROUND

Oral Submucous Fibrosis (OSMF) is an oral potentially malignant disorder (OPMD) that commonly occurs in the South Asian population as there is high usage of areca nut. There has been extensive research on the pathogenesis and treatment of this condition. It is well-established in the scientific literature that mast cells (MC) have a definitive role in several inflammatory disorders. OSMF being a chronic inflammatory disorder, is also expected to have increased MCs. Hence, this review aims to evaluate the role of MCs in the pathogenesis of OSMF.

METHODS

A systematic search of articles was performed by two of the authors independently in PubMed, Scopus, Embase, Web of Science, and Google Scholar using the appropriate keywords and Boolean terms. The risk of bias was assessed using the Modified Newcastle-Ottawa Scale. The meta-analysis was performed with R studio software (Version: 4.4.0, Year: 2024, Company: The R foundation for statistical computing).

RESULTS

The search retrieved 36 studies, of which 16 were suitable for the review. There is evidence for a marked increase in the number of MCs in OSMF than the normal mucosa upon analyzing the retrieved articles. However, when comparing the grades of OSMF, there are variations in the reports. As all the retrieved articles were case-control studies, the risk of bias was analyzed using the Modified New Castle Ottawa Scale. All the studies scored in the good category (Score 6-9). The pooled effect size shows the Standard Mean Deviation (SMD) to be 0.09, 95% confidence interval (CI) [-0.18;0.37] to lie on either side of no effect. Hence the role of MCs in OSMF has not been established because of homogeneity and consistent sampling error.

CONCLUSION

Our systematic review does suggest a definitive role of mast cells in the progression of OSMF. However, there is a lack of methodological rigor in the included studies. This may contribute to diluting the results.

Mast cells in oral lichen planus and oral lichenoid lesions related to dental amalgam contact

The aim of this study was to analyze the expression of mast cell markers toluidine blue, c-kit, and tryptase and presence of mononuclear inflammatory cells in oral lichen planus (OLP) and oral lichenoid lesions related to dental amalgam. Nineteen specimens of OLP, OLLC, and healthy oral mucosa were selected. Mononuclear inflammatory cells were analyzed. Histochemical and immunohistochemical analyses were performed using toluidine blue, anti-c-kit and anti-tryptase reagents, and the results were quantified in areas A and B of connective tissue. Mast cells of all OLP and OLLC samples were positive for toluidine blue, c-kit, and tryptase. The density of toluidine blue+, c-kit+ and tryptase+ mast cells was higher in tissue with OLP and OLLC compared with healthy controls (p < 0.05). No difference was noted in mast cells density between OLP and OLLC (p > 0.05). The density of tryptase+ mast cells was higher in the subepithelial region (area A) than the region below it (Area B) in OLLC (p = 0.047). The mononuclear inflammatory cell density was higher in OLLC compared to OLP, but without statistical significance (p > 0.05). A positive statistical correlation was found between mononuclear immune cells and density of c-kit+ and tryptase+ mast cells in OLP (r = 0.943 and r = 0.886, respectively). Our data demonstrate that the etiopathogenesis process of OLP and OLLC modulates the expansion and degranulation of mast cells; mast cells density, however, was similar between OLP and OLLC. The distribution of mast cells appears to vary along the lamina propria.

The Immune Cells in the Development of Oral Squamous Cell Carcinoma

A still unresolved issue surrounding tumor formation concerns the role that the immune system plays in preventing the formation and progression of neoplasia, including oral squamous cell carcinoma (OSCC). Antitumor immunity has historically been seen as a critical barrier for cancer cells to develop, grow and spread, and this can be modulated using immunotherapies to achieve antitumor clinical responses. However, it has recently become clear that tumor-associated immunity, particularly the inflammatory microenvironment, has the paradoxical effect of enhancing tumorigenesis and progression. In this review, we discuss the multifaceted function of infiltrating immune cells in suppressing or promoting premalignancy and cancer. In particular, we report on the evidence supporting a role for T lymphocytes, dendritic cells, macrophages, and neutrophils in the development and progression of oral potentially malignant disorders (OPMD) and OSCC. We also draw attention to the clinical relevance of immune cell phenotypes and associated molecules for use as biomarkers and to the translatability of current research findings to improve classification systems and precision medicine in patients with OSCC.

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.

Precancerous Lesions of the Head and Neck Region and Their Stromal Aberrations: Piecemeal Data

Head and neck squamous cell carcinomas (HNSCCs) develop through a series of precancerous stages from a pool of potentially malignant disorders (PMDs). Although we understand the genetic changes that lead to HNSCC, our understanding of the role of the stroma in the progression from precancer to cancer is limited. The stroma is the primary battleground between the forces that prevent and promote cancer growth. Targeting the stroma has yielded promising cancer therapies. However, the stroma at the precancerous stage of HNSCCs is poorly defined, and we may miss opportunities for chemopreventive interventions. PMDs already exhibit many features of the HNSCC stroma, such as inflammation, neovascularization, and immune suppression. Still, they do not induce cancer-associated fibroblasts or destroy the basal lamina, the stroma's initial structure. Our review aims to summarize the current understanding of the transition from precancer to cancer stroma and how this knowledge can reveal opportunities and limitations for diagnostic, prognostic, and therapeutic decisions to benefit patients. We will discuss what may be needed to fulfill the promise of the precancerous stroma as a target to prevent progression to cancer.

A Correlation of Serum Histamine and Mast Cell Count with the Established Prognosticators in Oral Cancer

Context

We undertook this study in view of the rising interest in the interactions between tumor cells and mast cells in the tumor microenvironment and the mounting evidence of the role of mast cells in the prognosis of various cancers.

Aims

The aim of the study is to determine the prognostic utility of mast cells and their mediators in oral squamous cell carcinoma (OSCC).

Settings and Design

This is a cross-sectional analytical study. A total of 41 cases were studied for determining the correlation of mast cell counts with histopathological prognostic variables and 29 cases for determining the serum histamine levels and to further correlate the values with the histopathologic determinants.

Subjects and Methods

Mast cell assessment was done using Toluidine blue stain on tissue sections while histopathological prognostic factors were evaluated with routine stains. The serum histamine levels were obtained by sandwich enzyme linked immunosorbent assay (ELISA).

Statistical Analysis

Mann-Whitney U-test was used to test the difference between parameters and a Spearman correlation coefficient was used. P < 0.05 was considered significant for statistical analysis.

Results

We found statistically significant correlations between increased median mast cell counts and higher grade of tumor, presence of lymphovascular invasion, greater depth of invasion, and presence of regional lymph node involvement. The serum histamine values correlated only with the depth of tumor invasion.

Conclusions

Hence, as per our results, we suggest the use of mast cell counts in OSCC cases as a prognostic indicator in conjunction with other clinicopathological factors. At the same time, we acknowledge the fact that extensive studies are required to establish the role of mast cell mediators in the prognostic curve of oral cancer patients.

Carcinogenic Effects of Areca Nut and Its Metabolites: A Review of the Experimental Evidence

Oral cancers (OC) are among the most frequent malignancies encountered in Southeast Asia, primarily due to the prevalent habit of betel quid (BQ) and smokeless tobacco use in this region. Areca nut (AN), the primary ingredient in BQ, contains several alkaloids, including arecoline, arecaidine, guvacoline, and guvacine. These have been associated with both the AN abuse liability and carcinogenicity. Additionally, variations in AN alkaloid levels could lead to differences in the addictiveness and carcinogenic potential across various AN-containing products. Recent studies based on animal models and in vitro experiments show cellular and molecular effects induced by AN. These comprise promoting epithelial-mesenchymal transition, autophagy initiation, tissue hypoxia, genotoxicity, cytotoxicity, and cell death. Further, clinical research endorses these undesired harmful effects in humans. Oral submucosal fibrosis, a potentially malignant disease of the oral cavity, is predominantly reported from the geographical areas of the globe where AN is habitually chewed. OC in chronic AN users presents a more aggressive phenotype, such as resistance to anti-cancer drugs. The available evidence on the carcinogenicity of AN based on the findings reported in the recently published experimental studies is discussed in the present review.

Application of Augmented Reality Navigation in Treatment With Fibrosis Dysplasia

OBJECTIVE

In order to reduce the possibility of accidental injury to neurovascular and important tissues, this research conduct preoperative design and intraoperative guidance for fibrous dysplasia through augmented reality technology.

METHODS

Five patients with fibrous dysplasia were selected for three-dimensional (3D) computed tomography (CT) scan and 3D model was reconstructed. Considering the navigation plan was comprehensively, the guide plate (composed of card groove, connector, and fixator) was designed and 3D printed. Three-dimensional software was used to unify the coordinates of the surgical plan and the guide plate, and the relative position was fixed. Then, the virtual and real overlapping registration is completed on the physical model. Pattern recognition technology is used to identify pre-defined markers in the video images before operation. Finally, the registration results are superimposed into the surgical field of vision to guide and remind surgeons.

RESULTS

In this study, the navigation based on augmented reality technology was used in the surgical treatment of 5 cases patients with fibrous dysplasia. The 3D navigation information was displayed in real time in the operative field. The operation was accurate and the postoperative effect was good.

CONCLUSIONS

This paper introduces an effective visual navigation surgical method in treatment with fibrous dysplasia. The augmented-reality based navigation system achieves individualized precise treatment by displaying 3D navigation directly in the surgical field. It is an effective auxiliary method for future research on craniofacial surgery.

Oral Lichen Planus - Related Connection with HLA-System Antigens

AIM

To determine whether there is an immunogenic connection and antigen difference between the HLA antigens in the erosive (EOLP) and reticular (ROLP) oral lichen planus.

MATERIALS AND METHOD

73 patients with ROLP and EOLP have been tested. Typing of the HLA antigens has been made for locus A and B. The typing of the HLA was conducted with the use of microlymphocyto toxic test by Terasaki. The reading of the findings has been conducted with an inverse microscope. When a reaction has 4 points it is considered to be positive.

RESULTS

The most frequently typified antigens in ROLP from locus A are HLA А2 (57.57%) and А3 (33.33)%, and for locus B 21.21%. In EOLP it is А9 (8888%). In locus B a connection has been found with HLA B8 (77.77%). The statistical analysis with the ×2 test has shown that the carriers of HLA A9 display a relative risk (RR) of 3.65 and ×2=20.72. Consequently, there is high static importance for locus A p<0,001. For locus B, In EOLP for HLA B8, RR=6. 7 ×2=37.64 and p<0,001. ROLP has shown association with HLA A3, where RR=2. 31 and ×2 =9.14 and p<0.05.

CONCLUSIONS

In ROLP A3 antigen and in EOLP A9 and A8 may be considered as carriers with proneness to OLP.

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.

Multifaceted Mechanisms of Areca Nuts in Oral Carcinogenesis: the Molecular Pathology from Precancerous Condition to Malignant Transformation

Oral cancer is one of the most frequent malignant diseases worldwide, and areca nut is a primary carcinogen causing this cancer in Southeast Asia. It has been widely reported that areca nut induced several cytotoxic effects in oral cells, including ROS generation, inflammation, tissue hypoxia, DNA damage, and cell invasion. Recently, through chronic exposure model, more extensive pathological effects due to areca nut have been found. These include the induction of autophagy, promotion of epithelial- mesenchymal transition, and facilitation of cancer stemness conversion. Clinical findings support these adverse effects. Oral submucosal fibrosis, a premalignant condition, is prevalent in the area with habitual chewing of areca nuts. Consistently, oral cancer patients with habitual chewing areca nut exhibit more aggressive phenotypes, including resistance to chemo-radiotherapy. In this review, we comprehensively discuss and concisely summarize the up-to-date molecular and cellular mechanisms by which areca nuts contribute to malignant transformation. This review may provide critical information regarding clinical applications in risk assessment, disease prevention, diagnosis, and personalized therapeutics for areca nut-induced oral malignancy.

Effect of tumor microenvironment on pathogenesis of the head and neck squamous cell carcinoma: a systematic review

The tumor microenvironment (TME) is comprised of many different cell populations, such as cancer-associated fibroblasts and various infiltrating immune cells, and non-cell components of extracellular matrix. These crucial parts of the surrounding stroma can function as both positive and negative regulators of all hallmarks of cancer development, including evasion of apoptosis, induction of angiogenesis, deregulation of the energy metabolism, resistance to the immune detection and destruction, and activation of invasion and metastasis. This review represents a summary of recent studies focusing on describing these effects of microenvironment on initiation and progression of the head and neck squamous cell carcinoma, focusing on oral squamous cell carcinoma, since it is becoming clear that an investigation of differences in stromal composition of the head and neck squamous cell carcinoma microenvironment and their impact on cancer development and progression may help better understand the mechanisms behind different responses to therapy and help define possible targets for clinical intervention.

Evaluation of Mast Cell Density in the Tumor Microenvironment in Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma

The objective of this study was to compare mast cell density (MCD) in oral epithelial dysplasias (OED) and oral squamous cell carcinoma (OSCC) and determine its correlation with clinical and histopathologic parameters and the degree of tumor differentiation. Thirty OSCC samples, 14 OED samples, and 4 non-neoplastic oral mucosa samples were analyzed by immunohistochemistry to determine MCD based on the expression of MC tryptase. In addition, MCs were categorized morphologically into degranulated and granulated cells. MCD was significantly higher in OSCC lesions with a greater degree of differentiation (P=0.04). No significant difference in MCD was detected between mild and moderate OED samples (P=0.09). Our findings indicate that MCs are present in the tumor microenvironment and may be associated with a better prognosis.

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.

Proliferative Effects of Histamine on Primary Human Pterygium Fibroblasts

Purpose. It has been confirmed that inflammatory cytokines are involved in the progression of pterygium. Histamine can enhance proliferation and migration of many cells. Therefore, we intend to investigate the proliferative and migratory effects of histamine on primary culture of human pterygium fibroblasts (HPFs). Methods. Pterygium and conjunctiva samples were obtained from surgery, and toluidine blue staining was used to identify mast cells. 3-[4, 5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) was performed to evaluate the proliferative rate of HPFs and human conjunctival fibroblasts (HCFs); ki67 expression was also measured by immunofluorescence analysis. Histamine receptor-1 (H1R) antagonist (Diphenhydramine Hydrochloride) and histamine receptor-2 (H2R) antagonist (Nizatidine) were added to figure out which receptor was involved. Wound healing model was used to evaluate the migratory ability of HPFs. Results. The numbers of total mast cells and degranulated mast cells were both higher in pterygium than in conjunctiva. Histamine had a proliferative effect on both HPFs and HCFs, the effective concentration (10 μmol/L) on HPFs was lower than on HCFs (100 μmol/L), and the effect could be blocked by H1R antagonist. Histamine showed no migratory effect on HPFs. Conclusion. Histamine may play an important role in the proliferation of HPFs and act through H1R.

Computer aided morphometric analysis of oral leukoplakia and oral squamous cell carcinoma

We compared the changes in the cells in the basal layer of normal mucosa, oral leukoplakia with dysplasia and different grades of oral squamous cell carcinoma (OSCC) using computer aided image analysis of tissue sections. We investigated three morphometric parameters: nuclear area (NA), cell area (CA) and their ratio (NA:CA). NA and NA:CA ratio showed a statistically significant increase from dysplasia to increasing grades of OSCC. Nuclear size was useful for differentiating normal tissue, potentially malignant leukoplakia and OSCC.