The extent of lymph node metastasis is a major determinant in the prognosis of oral squamous cell carcinoma (OSCC). Abnormalities of cell adhesion molecules are known to play an important role in invasion and metastasis of cancer cells through the loss of cell-to-cell adhesion. In this study, we isolated highly invasive clones from an OSCC cell line established from a lymph node metastasis by using an in vitro invasion assay method and compared the abnormalities of cell adhesion molecule E-cadherin and ␤-catenin in these cells. The isolated, highly invasive clones showed significant invasive capacity and reduction of E-cadherin and membranous ␤-catenin protein in comparison with parent cells. We found that reduced expression of E-cadherin was due to methylation of its promoter region. In fact, most invasive and metastatic area of OSCCs showed reduced expression and methylation of E-cadherin. Moreover, we found that reduced expression of membranous ␤-catenin was due to its protein degradation. Reduced expression of membranous ␤-catenin was also found frequently in invasive and metastatic areas of OSCCs. In summary, invasion and metastasis of OSCC cells require methylation of Ecadherin and/or degradation of membranous ␤-catenin. In addition, we suggest that the method of isolation of highly invasive clones may be useful for studies aimed at discovering novel genes involved in invasion and metastasis.

Objective: The aim of this study was to document the clinicopathologic characteristic of salivary gland tumors in Tehran, Iran, over a 15-year period.Material and Method: a retrospective study was conducted on salivary gland tumors diagnosed at two pathology centers of Shahid Beheshti University of Medical Sciences from March 2000 to March 2015. Patient age, sex, tumor site and frequency, as well as clinical and radiographic features and histopathologic diagnosis constituted the main analysis outcome measures. Results:Of the 45429 biopsies conducted over 15 years, 6065 (13.3%) cases were oral and maxillofacial lesions and 937 (15.4%) of these had tumoral diagnoses. Of the 937 tumoral cases, 184 (19.6%) were salivary gland tumors and among 184 cases, 65 (35.3%) were benign and 119 (64.7%) were malignant. Pleomorphic adenoma was the most frequently occurring tumor, comprising 32.6% of all tumors, followed by mucoepidermoid carcinoma (27.1%) and adenoid cystic carcinoma (22.2%). Tumors were frequently reported in minor salivary glands (75%), particularly in the palate with 89 (48.4%) cases. The peak ages of incidence were the fourth and sixth decades of life. Malignant salivary gland tumors showed a predilection for females (72.9%), which was statistically significant (P<0.01). Conclusion:The data presented herein are similar to previously published reports in other countries and other areas of Iran. however, some differences were observed in our study, such as higher overall frequency, a lower mean age of patients with malignant tumors, and the particular sites of involvement. These differences can be attributed to racial factors, the pathology centers of sample collection, and the duration of the studies.

Loss of p16INK4a expression occurred in initial stages of oral squamous cell carcinoma. Evaluation of TS and CS for p16INK4a might be a useful clinical indicator concerning the tumor. However, gene mutation is believed to have minor rate of genetic alteration in carcinogenesis.

These findings support the histiocyte/macrophage nature of multinucleated giant cells and mononuclear cells. Overexpression and high intensity score of CD68 in mononuclear cells and the high intensity score of factor VIII-RA in endothelial cells represent less aggressive behavior in central giant cell granuloma.

Background and Aim: Fibrous dysplasia (FD) and ossifying fibroma (OF) are the most important fibro-osseous lesions (FOLs) of the jaws with similarities in radiographic and morphological features while showing completely different biological behavior. Limited studies have been evaluated immunohistochemistry markers, such as osteopontin (OPN) and osteocalcin to help differentiate these two lesions. This study aimed to assess the immunoexpression of OPN and Ki67 as potential markers for differentiation of different FOLs. Materials and Methods: This cross-sectional study was conducted on 12 FD, 19 OF, and eight FOL samples retrieved from the archives of the department of oral pathology. The specimens were examined immunohistochemically using streptavidin-biotin method for OPN and Ki67. The intensity score (IS), proportional score (PS) and total score (TS) were assessed in hard and soft tissue matrix and in mesenchymal cells for Ki67. The data were analyzed by independent samples Kruskal-Wallis. Results: Osteopontin showed positive immunoreaction in both stromal and trabecular components of all FDs and OFs. Among the scores, PS and TS of bone trabeculae were significantly different in FD and OF (P=0.005). Nevertheless, no significant difference was observed in Ki67 expression in mesenchymal cells (P=0.880) and OPN scores in soft tissue matrix between the lesions; their P-value were 0.336, 0.340 and 0.415 for IS, TS, and PS, respectively. Conclusion: Osteopontin can serve as a useful marker for differential diagnosis of FD and OF. However, we suggest evaluation of other NCMPs, especially functionally similar molecules such as bone sialoproteins (BSPs) in FOLs for differential diagnosis.