INTRODUCTION:Oral cancer is a major health problem, causing high morbidity and mortality rates. Oral squamous cell carcinoma (OSCC) accounts for 90-95% of all oral malignancies. During the last decade, significant evidence has suggested that inflammation plays an important role in tumorigenesis, and microenvironment-derived signals which are important constituents in all tumors. Toll-like receptors (TLRs) are classical signals that play a key role in the innate immune system. They drive the inflammatory response and control the cellular proliferation and survival by stimulating the immune cells and promoting integrated processes of inflammation and tissue repair. This can predict that TLR-4 may be of great significance in tumors. Hence, this study is to evaluate and correlate the expression of TLR-4 in various grades of oral squamous cell carcinoma (OSCC). OBJECTIVES: To evaluate and correlate the expression of TLR-4 in different histopathological grades of OSCC MATERIALS AND METHODS: An immunohistochemical (IHC) study using the TLR-4 antibody were done on 50 surgical specimens and 10 normal mucosal tissues taken from OSCC patients and healthy individuals, respectively. The staining were performed using a Labeled Strept-Avidin Biotin complex method (LSAB) RESULTS: TLR-4 was expressed in human OSCC biopsies and the expression level was correlated with the tumor differentiation. Higher expression was detected in the well and the moderately differentiated squamous cell carcinomas than the poorly differentiated ones. CONCLUSIONS: TLR-4 expression could be a prognostic factor in oral squamous cell carcinoma cases as expression was detected in the well and moderately differentiated higher than poorly differentiated squamous cell carcinomas.

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Introduction:Odontogenic tumors constitute a wide range and diverse kind of lesions derived from the tooth forming apparatus and its remnants. They originate from epithelium, ectomesenchyme or both. Varying degrees of inductive interaction between these embryonic components of the developing tooth germ exist. Nestin is one of the intermediate filaments constituting the cytoskeleton and is known as a marker of neural stem cells or progenitor cells. Human Nestin expression continues during tooth development and disappears when development is complete. Aim of the work: To study the expression of Nestin in different odontogenic tumors, and to highlight the incidence of odontogenic tumors in the Faculty of dentistry, Alexandria University, Egypt in the past 10 years. Material and Methods: Immunohistochemical analysis was performed on 22 surgical specimens of odontogenic tumors and one control specimen from normal tooth germ.Immunohistochemical staining was performed using a Labeled Strept-Avidin Biotin complex method (LSAB). Results:Almost all the ameloblastomas were negative for Nestin while all cases of odontogenic fibromyxoma , myxoma and odontogenic fibroma showed intense brownish cytoplasmic reaction in both the ectomesenchymal cells and the odontogenic epithelial rests. Ameloblastic fibroma and ameloblastic fibro-odontom cases showed immunopositivity of Nestin in the ameloblast like cells and stellate reticulum like cells as well as the stromal cells. Calcific structures such as dentinoid as well as hamartomatous lesions mainly odontomes were completely negative for Nestin. The results of the statistical analysis revealed higher prevalence of keratocystic odontogenic tumor followed by ameloblastoma. Conclusion:Nestin is expressed in some odontogenic tumors in which the ectomesenchyme of the neural crest origin, constituting a part of their proliferated tissue. In the statistical analysis which was done in this study,there was statistical difference regarding types.

INTRODUCTION: Oral lichen planus (OLP) is a relatively common chronic inflammatory and a potentially malignant disorder of oral mucosa. Tumor necrosis factor-alpha (TNFα) has been pointed as a key cytokine in OLP. OBJECTIVES: To evaluate whether the salivary levels of TNFα were changed in patients with erosive oral lichen planus (EOLP). METHODOLOGY: A total of fourteen cases of EOLP with and without dysplastic changes, along with seven age matched healthy controls were included in this study. Samples of unstimulated saliva was collected, centrifuged and analyzed with enzyme linked immunosorbent assay (ELISA). RESULTS: There was a statistically significant increase in the salivary levels of TNFα in patients of the two study groups when compared to the control group. CONCLUSIONS: TNFα plays a role in pathogenesis and carcinogenesis of EOLP, and can be used as a useful marker and indicator for subjects at high risk to develop OLP as a potentially malignant lesion.

INTRODUCTION: Oral squamous cell carcinoma (OSCC) accounts for more than 90% of all oral cancers with high mortality and morbidity rates. Lymph node (LN) metastasis is one of the most important factors in the treatment and prognosis of patients with OSCC. It reduces the overall survival by nearly half. Toll like receptors (TLRs) are evolutionarily conserved proteins and major type of receptors involved in both innate and adaptive immunities and defense against pathogens. TLR4 was the first member of the TLR family to be discovered. It was verified that TLR4 is expressed in many types of tumors including OSCC. The correlation between the expression of this receptor and the presence of nodal metastasis has been studied. Involvement of TLR4 in the invasion and metastasis potentials may thus suggest the use of this protein as a prognostic marker for OSCC and may provide a new insight in the treatment strategy. OBJECTIVES: The aim of the present study was to assess the expression of TLR4 in the primary tumor of OSCC and correlate it with the lymph node status. MATERIALS AND METHODS: TLR4 expression was calculated in 30 OSCC cases. The specimens were taken from the primary tumor of 15 cases proved to have positive lymph nodes and another 15 cases with negative lymph nodes. Immunohistochemical (IHC) staining was performed using the Labeled Strept-Avidin Biotin complex method (LSAB), using the anti-TLR4 antibody. RESULTS: TLR4 was expressed in the OSCC cases and was significantly higher in cases with positive lymph node metastasis than those without. CONCLUSIONS: TLR4 expression could be used as a prognostic marker for OSCC as an indicator for metastasis.