Cells In Oral Lesions Research Articles

Contemporary Updates on the Role of Mast Cells in Oral Lesions: A Review

Mast cell (MCs) is considered the immune cell of myeloid lineage and make a crucial role in the inflammatory process in several types of oral diseases. This mast cell contains 50–200 large granules which are inflammatory mediators, including rich in histamine and heparin. It is mainly found in the connective tissues of the oral mucosa like nerves, blood vessels, and subepithelial areas of the human body. These cells have a key role in the maintenance of many physiologic functions of the body and thus their number was altered in various pathophysiologic diseases of the oral cavity such as benign and malignant tumors, reactive lesions, autoimmune diseases, odontogenic cyst, tumors, etc. The present paper is focused on the current concept and updates on the role and function of mast cells in physiologic and pathologic conditions of the oral cavity.

Mucous and Ciliated Cells in Oral Lesions: Potential Pitfall of Additional Two Cases

Mucous and Ciliated Cells in Oral Lesions: Potential Pitfall of Additional Two Cases

Peroxiredoxin 2 is highly expressed in human oral squamous cell carcinoma cells and is upregulated by human papillomavirus oncoproteins and arecoline, promoting proliferation

Peroxiredoxin 2 (PRDX2) is upregulated in various cancers including oral squamous cell carcinoma (OSCC). It is a known tumor promoter in some cancers, but its role in OSCC is unclear. This study aimed to investigate the effect of arecoline, an alkaloid of the betel nut, and human papillomavirus type 16 (HPV16) E6/E7 oncoproteins on induction of PRDX2 expression, and also the effects of PRDX2 overexpression in oral cell lines. Levels of PRDX2 protein were determined using western blot analysis of samples of exfoliated normal oral cells (n = 75) and oral lesion cells from OSCC cases (n = 75). Some OSCC cases were positive for HPV infection and some patients had a history of betel quid chewing. To explore the level of PRDX2 by western blot, the proteins were extracted from oral cell lines that were treated with arecoline or retroviruses containing HPV16 E6 gene and HPV16 E6/E7 expressing vector. For analysis of PRDX2 functions, cell proliferation, cell-cycle progression, apoptosis and migration was compared between oral cells overexpressing PRDX2 and cells with PRDX2-knockdown. PRDX2 expression levels tended to be higher in OSCC samples that were positive for HPV infection and had history of betel quid chewing. Arecoline treatment in vitro at low concentrations and overexpression of HPV16 E6 or E6/E7 in oral cells induced PRDX2 overexpression. Interestingly, in oral cells, PRDX2 promoted cell proliferation, cell-cycle progression (G2/M phase), cell migration and inhibited apoptosis. Upregulation of PRDX2 in oral cells was induced by arecoline and HPV16 oncoproteins and promoted growth of OSCC cells.

Comprehensive Data of P53 R282 Gene Mutation with Human Papillomaviruses (HPV)-Associated Oral Squamous Cell Carcinoma (OSCC).

Alterations of the P53 gene and human papillomavirus (HPV) infection are associated with development of oral squamous cell carcinoma (OSCC). We aimed to identify mutation of P53 exon 8 codon 282 in OSCC and correlate these with HPV infection as well as histopathological grade of OSCC. Samples of known HPV infection status were studied including oral lesion cells, formalin-fixed paraffin embedded (FFPE) tissues from OSCC and exfoliated oral cells of matched age-sex controls. P53 exon 8 mutation was detected using the polymerase chain reaction (PCR). Mutation of codon 282 was identified by allele-specific oligonucleotide typing (ASO) using EvaGreen real-time PCR. The PCR products were analyzed by gel electrophoresis and melting curve analysis. Mutation of P53 exon 8 was seen in 81.7% and 69.6% of FFPE OSCC tissues and oral lesion cells, respectively. This was significantly higher than in controls (16.7%). Frequency of mutation did not differ between HPV-positive samples (62.5% and 81.8% in oral lesion cells and FFPE tissue samples, respectively) and HPV-negative samples (73.3% and 81.5% in oral lesion cells and FFPE tissue samples, respectively). This finding is similar to P53 codon 282 mutation that was found only in FFPE tissues (35.0%) and oral lesion cells (32.6%) from both HPV-positive and negative OSCC. Interestingly, frequency of mutation was higher in well-differentiated OSCC with HPV-infection (28.1%) than without HPV (14.8%). This result demonstrated a mutation hot spot in P53 associated with oral carcinogenesis and might be useful to guide chemotherapeutic modality for HPV-associated OSCC in northeast Thailand.

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

ABSTRACTMast 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.

Indomethacin Treatment of Mice with Premalignant Oral Lesions Sustains Cytokine Production and Slows Progression to Cancer.

Current treatment options for head and neck squamous cell carcinoma (HNSCC) patients are often ineffective due to tumor-localized and systemic immunosuppression. Using the 4-NQO mouse model of oral carcinogenesis, this study showed that premalignant oral lesion cells produce higher levels of the immune modulator, PGE2, compared to HNSCC cells. Inhibiting prostaglandin production of premalignant lesion cells with the pan-cyclooxygenase inhibitor indomethacin stimulated their induction of spleen cell cytokine production. In contrast, inhibiting HNSCC prostaglandin production did not stimulate their induction of spleen cell cytokine production. Treatment of mice bearing premalignant oral lesions with indomethacin slowed progression of premalignant oral lesions to HNSCC. Flow cytometric analysis of T cells in the regional lymph nodes of lesion-bearing mice receiving indomethacin treatment showed an increase in lymph node cellularity and in the absolute number of CD8+ T cells expressing IFN-γ compared to levels in lesion-bearing mice receiving diluent control treatment. The cytokine-stimulatory effect of indomethacin treatment was not localized to regional lymph nodes but was also seen in the spleen of mice with premalignant oral lesions. Together, these data suggest that inhibiting prostaglandin production at the premalignant lesion stage boosts immune capability and improves clinical outcomes.

Autocrine motility-stimulatory pathways of oral premalignant lesion cells

Patients with premalignant oral lesions have varying levels of risk of developing oral squamous cell carcinoma (OSCC), whose aggressiveness requires increased motility. Not known is if and how premalignant oral lesion cells acquire the increased motility characteristic of OSCC. This was addressed by immunohistochemical analysis of banked premalignant lesion tissues and by functional analyses using cultures established from premalignant oral lesions and OSCC. These studies showed premalignant oral lesion cells and OSCC to be more motile than normal keratinocytes. Concomitantly, levels of ceramide were reduced. The activity of the protein phosphatase PP-2A, which restricts motility and which can be activated by ceramide, was also diminished. This was due to IL-10 released from premalignant lesion cells. Treatment with a membrane-permeable ceramide restored PP-2A activity and blocked migration. These studies show an autocrine motility-stimulatory pathway that is mediated in premalignant lesion cells by IL-10 through its reduction of ceramide levels and inhibition of PP-2A activity.

Oral premalignant lesions induce immune reactivity to both premalignant oral lesions and head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is an aggressive malignancy, and despite advances in treatments, the 5-year survival has remained at less than 50%. One treatment strategy is to focus on patients with premalignant oral lesions that carry a high-risk for developing recurrent premalignant lesions and HNSCC disease. As an initial attempt to determine if immune therapy has the potential to be protective in these patients, studies determined if premalignant lesions express tumor antigens that have previously been shown to be expressed on HNSCC. Immunohistochemical analyses showed prominent expression of epidermal growth factor receptor in premalignant lesions, even in lesions with mild dysplasia. MUC-1 and carcinoembryonic antigen were expressed in most patient samples, while NY-ESO-1 was less frequently expressed. Each of these antigens was expressed on HNSCC. This provided the rationale for determining if premalignant oral lesions could be used to stimulate autologous peripheral blood mononuclear leukocytes (PBML) to react against heterologous premalignant lesions and HNSCC. Following sensitization with autologous premalignant lesions, PBML responded to a challenge with either heterologous premalignant oral lesion cells or HNSCC by releasing IFN-gamma. In addition, sensitization with autologous premalignant lesion lysates generated cytolytic activity by both PBML and T cells against allogeneic premalignant lesion cells and HNSCC. These studies show the feasibility of using premalignant oral lesions to stimulate immune reactivity against both premalignant oral lesions as well as HNSCC.

Characterization of the Immune Status of CD8+T Cells in Oral Lesions of Human Immunodeficiency Virus-Infected Persons with Oropharyngeal Candidiasis

Oropharyngeal candidiasis (OPC) remains the most common oral infection in human immunodeficiency virus (HIV) disease. In a high percentage of HIV(+) persons with reduced CD4(+) T cells, oral lesions with Candida present at the outer epithelium have an accumulation of CD8(+) T cells at the epithelium-lamina propria interface associated with reduced expression of the mucosal cell-trafficking adhesion molecule E-cadherin. The purpose of the present study was to characterize the immune status of these CD8(+) T cells. Immunohistochemical staining for phenotypic and activation and costimulation markers was performed on frozen biopsy tissue sections from HIV(+) OPC(+) persons with accumulated CD8(+) T cells. CD8(+) T cells consisted primarily of central memory cells by virtue of positive CD45RO (memory) and CD27 (central memory) expression. However, concomitant negative expression of CD62L and CCR7 (effector memory) was suggestive of a transitioning memory phenotype within the tissue. Despite this, the cells are considered to be activated on the basis of positive expression of CD69. The CD8(+) T cells are not considered to be NK T cells or anti-HIV CD8(+) T cells because of negative or low expression of CD161 and vascular cell adhesion molecule, respectively. These results suggest that the accumulated mucosal migratory-challenged CD8(+) T cells are otherwise normal memory T cells in an activated state.

Detection of HPV in Japanese and Chinese oral carcinomas by in situ PCR.

Human papillomavirus (HPV) is established as the cause of almost 100% of cervical carcinomas. However, the association of HPV with oral squamous cell carcinomas (SCCs) is less well understood. We examined the prevalence of HPV in oral SCCs in samples of Japanese and Chinese populations. Using in situ polymerase chain reaction (PCR) analysis (MY09 and MY11 consensus primers), HPV was detected in the nucleus of epithelia and tumor cells in oral lesions. Analysis revealed the specific presence of HPV DNA in all cases of SCC in our Japanese (10/10) and Chinese (10/10) population samples. These results suggest that HPV infection could be one of several risk factors contributing to oral SCC in Japanese and Chinese.

Expression of the CA1 determinant by carcinomas and by non-malignant epithelial cells in oral lesions.

The expression of the Ca antigen was investigated in 5 groups of oral lesions comprising 7 squamous cell carcinomas, 2 pre-invasive carcinomas, 7 lesions of types believed to predispose to carcinoma, 19 lesions of types that do not predispose to carcinoma and 5 biopsies of normal oral mucosa. Using an indirect immunoperoxidase method, the neoplastic epithelium reacted positively with the Ca1 antibody in only 4 out of 7 oral squamous cell carcinomas and the reaction varied between the specimens as to the intensity and number of positively stained cells. Several benign oral lesions specifically bound the Ca1 antibody in areas of epithelium showing infiltration with inflammatory cells. These lesions comprised 5 fibrous epulides, 1 pyogenic granuloma, 1 denture-induced hyperplasia and 1 non-diagnostic ulcer. We conclude that the Ca1 antibody is not sufficiently specific for the carcinoma to be of value in the diagnosis of malignant and premalignant lesions of the oral mucosa.