Detection of the Epstein-Barr virus and DNA-topoisomerase II- α in recurrent and nonrecurrent giant cell lesion of the jawbones.

The aims of this study were to determine whether the expression of Topo II-α correlates with presence of EBV in giant cell lesion of the jawbones and whether it is predictive of clinical biologic behavior of these lesions. Paraffin-embedded tissues from 8 recurrent and 7 nonrecurrent cases of bony GCLs and 9 peripheral giant cell lesions (PGCLs) as a control group were assessed for the expression of EBV and Topo II-α using immunohistochemistry. The results showed positive staining for Topo II-α in mononuclear stromal cells (MSCs) and multinucleated giant cells (MGCs). Student t-test showed that mean Topo II-α labelling index (LI) in recurrent cases was significantly higher than that in non-recurrent cases (P = 0.0001). Moreover, Spearman's correlation coefficients method showed a significant correlation between DNA Topo II-α LI and both of gender and site in these lesions. Moderate EBV expression in relation to the highest Topo II-α LI was observed in two cases of GCT. It was concluded that high Topo II-α LIs could be identified as reliable predicators for the clinical behavior of GCLs. Moreover, EBV has no etiological role in the benign CGCLs in contrast to its role in the pathogenesis of GCTs.

Inhibition of 4-NQO-induced F433 rat tongue carcinogenesis by oleuropein-rich extract.

Olive leaf extract provides nutritional support for detoxification at the cellular level, when the body is under stress. The present study aimed to evaluate the chemopreventive effect of oleuropein-rich extract (ORE) on 4-NQO-induced rat tongue carcinogenesis. Eighty male F344 rats, 6 weeks age were divided into 5 groups (10 animals each for groups 1 and 2 and 20 each for groups 3, 4, and 5). Group 1 served as an untreated control. Group 2 was given ORE-containing diet alone. Rats of groups 3, 4, and 5 were given daily 20 ppm 4-NQO in drinking water for 8 weeks. Group 4 was fed diets containing ORE, concomitantly with the time of carcinogen exposure and continued 1 week after its stoppage. Group 5 was fed diets mixed with ORE starting 1 week after cessation of 4-NQO treatment. The experiment was terminated when the rats aged 37 weeks, and all animals were euthanized. The tongues were carefully inspected for pathological lesions, excised, and were processed for c-Met and Ki-67 immunohistochemical examination. The gross inspection, histopathological and immunohistochemical results of the present study showed a beneficial regression effect of ORE on tumor progression, especially when it was administered concomitantly with 4-NQO rather than when given after the stoppage of the carcinogenic material. In conclusion, ORE has a chemopreventive role in tongue squamous cell carcinoma, and further studies are needed to explore the molecular mechanisms of its tumor suppressive effect at this level.

Relationship of survivin to clinical drug resistance in Burkitt's lymphoma of the head and neck region.

This study was designed to determine the potential role of survivin in the pathogenesis of Burkitt´s lymphoma (BL) and analyzing the relationship of its expression with response to therapy. The expression of survivin was investigated in seven archival tumor tissues of BL using the streptavidin-biotin complex technique. Immunohistochemical analysis showed that survivin expression was positive in 6 of 7 BL cases (85.7%). BL group with high survivin expression had poor response to chemotherapy than the group with low survivin expression (P=0.005). The results suggest that apoptosis inhibition by survivin is a significant prognostic parameter of poor response to chemotherapy in Burkitt's lymphoma.

Immunohistochemical study of syndecan-1 down-regulation and the expression of P35 protein in oral lichen planus: a clinicopathologic correlation with hepatitis C infection in the Egyptian population.

Several epidemiologic studies have shown the malignant transformation potential of oral lichen planus (OLP); however, it is not clear if this is in fact due to the premalignant nature of OLP or to the presence of some risk cofactors in patients with this pathologic condition. This study was conducted to evaluate the expression of p35 and syndecan-1 in 43 paraffin-embedded tissue specimens of OLP according to streptavidin-biotin technique and to investigate the possible association that might exist between such expression and the clinicopathologic types of OLP as well as some risk cofactors such as hepatitis C viral (HCV) infection among Egyptian population. A statistically significant strong correlation was found between HCV infection and clinicopathologic types of OLP. Suprabasal p35 staining together with altered syndecan-1 expression were significantly associated with atrophic-erosive type of OLP. Moreover, statistically significant difference was found between OLP with malignant transformation group (II) and OLP with no evidence for malignant transformation group (I) for both p35 and syndecan-1 expression (P < .01). This study confirms that a strong direct relationship existed between suprabasal p35 localization together with down-regulation of syndecan-1 immunoexpression and dysplastic changes of OLP and hence the possibility for malignant transformation. The HCV infection among Egyptian populations could be considered not only as etiologic factor in development of OLP but also as a direct factor in malignant transformation of this lesion.

Odontogenic tumors in Dakahlia, Egypt: analysis of 82 cases.

OBJECTIVE: This study was designed to analyze the frequency and distribution of different types of odontogenic tumors in Dakahlia, Egypt, and to compare them with various reports from other parts of the world. STUDY DESIGN: Records of the Oral and Maxillofacial Surgery and Oral Pathology Departments, Faculty of Dentistry, Mansoura University, with histologic diagnosis of odontogenic tumors (based on the World Health Organization classification, 2005), during a 15-year period, were analyzed. RESULTS: A total of 82 cases of odontogenic tumors were reported. Of these, (96.3%) were benign and (3.7%) were malignant. Ameloblastoma (41.5%) was the most frequent type, followed by keratocystic odontogenic tumor (19.5%), odontoma (13.4%), and odontogenic myxoma (8.5%). The mean age of the patients was 29.57 years, with a wide range (4-80 years). CONCLUSIONS: Odontogenic tumors show a definite geographic variation. In Dakahlia, Egypt, ameloblastoma and keratocystic odontogenic tumor are the most frequent odontogenic tumors, with distinct anatomic predilections.

Predictive value of cyclooxygenase 2 and Bcl-2 for cervical lymph node metastasis in mucoepidermoid carcinoma.

The expression of cyclooxygenase 2 (COX-2) is induced by growth factors, tumor promoters, and cytokines. It is correlated with carcinogenesis and apoptosis inhibition. This study was designed to investigate the expression of COX-2 and BCl-2 and to correlate their expressions with the clinicopathologic features in the mucoepidermoid carcinoma (MEC). The expression of COX-2 and BCl-2 proteins was investigated in 16 archival tumor tissues of MEC using the streptavidin-biotin complex technique. Clinical information was obtained through the computerized retrospective database from the tumor registry between 2001 and 2007. It revealed that grading system of MEC did not correlate with the presence or absence of node metastasis. The expression of COX-2 and BCl-2 was variably expressed in all the examined specimens. COX-2 and BCl-2 immunoreactivity was observed mainly in the cytoplasm of neoplastic cells. As regard the clinicopathologic parameters, there was no significant difference in expression rates of COX-2 in patients among age, sex, and MEC grades (P > .05). However, the expression of COX-2 in node-positive tumors was significantly higher than that of node-negative tumors (P = .001). For BCL-2 expression, there was no significant difference in expression rates of BCl-2 in patients among age, sex, site, clinical stage, and lymph node metastasis (P > .05), whereas a high significant difference was observed between BCl-2 staining index and MEC grades (P = .027). Moreover, there is a positive correlation between COX-2 expression and BCL-2 staining index (P = .000). COX-2 is a good predictor for lymph node metastasis as well as ideal therapeutic target for the prevention or treatment of MEC. BCl-2 and COX-2 are potentially useful prognostic markers for MEC.

The significance of Epstein Barr virus (EBV) & DNA topoisomerase II alpha (DNA-Topo II alpha) immunoreactivity in normal oral mucosa, oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC).

BACKGROUND: Head and neck cancer including oral cancer is considered to develop by accumulated genetic alterations and the major pathway is cancerization from lesions such as intraepithelial dysplasia in oral leukoplakia and erythroplakia. The relationship of proliferation markers with the grading of dysplasia is uncertain. The involvement of EBV in oral carcinogenesis is not fully understood. AIM: The present study was designed to investigate the role of EBV and DNA Topoisomerase II proportional (DNA-Topo II proportional) during oral carcinogenesis and to examine the prognostic significance of these protein expressions in OSCCs. METHODS: Using specific antibodies for EBV and DNA-Topo II proportional, we examined protein expressions in archival lesion tissues from 16 patients with oral epithelial dysplasia, 22 oral squamous cell carcinoma and 20 normal oral mucosa by immunohistochemistry. Clinical information was obtained through the computerized retrospective database from the tumor registry. RESULTS: DNA-Topo II proportional was expressed in all examined specimens. Analysis of Variance ANOVA revealed highly significant difference (P < 0.01) in young aged labial tissues and significant (P < or = 0.05) in gingival and not significant (P > 0.05) in inferior surface of tongue and in hard palatal tissues. Significant differences were observed between OEDs and NSE (P < 0.001) and SCCs and controls (P < 0.001), also, significant differences could be observed between SCCs and OEDs. DNA-Topo II proportional expression was significantly higher in tumors of low differentiation versus tumors of moderate and high differentiation (P < 0.001), DNA-Topo II proportional expression was correlated with age, tumor size, tumor stage, node metastasis and tumor differentiation, but not with gender and tumor site. None of normal squamous epithelium (NSE) expressed EBV. Heterogeneous reactivity for EBV was observed through the series of dysplasia and squamous cell carcinoma. Its expression increased progressively with lymph node metastasis and low tumor differentiation, but no significant association could be observed with other clinicopathological parameters. EBV protein expression was increased with elevated Topo II-proportional LI in OEDs and OSCCs. A tendency to positive correlation between EBV and Topo II proportional, variant expression was observed in OEDs but not in OSCCs. CONCLUSION: EBV and DNA Topo II-alphaLI expression are possible indicators in oral carcinogenesis and may be valuable diagnostic and prognostic indices in oral carcinoma.

Is collagenase-3 (MMP-13) expression in chondrosarcoma of the jaws a true marker for tumor aggressiveness?

BACKGROUND: Matrix metalloproteinases (MMPs) play an important role in the modeling and remodeling of the extracellular matrix in both physiologic and pathologic states and thus plays an important role in tumor progression. Human collagenase-3 (MMP-13) is a member of matrix metalloproteinase family of enzymes that was originally identified in breast carcinomas and subsequently detected during fetal ossification and in arthritic processes. AIM: The present study was designed to investigate the expression MMP-13 and to correlate its expression with clinicopathological parameters in chondrosarcoma of the jaws. METHODS: Archival tumor tissues from 11 patients with chondrosarcoma of the jaws were analyzed by immunohistochemistry for the expression of MMP-13. Clinical information was obtained through the computerized retrospective database from the tumor registry between 1998 to 2006. RESULTS: Eight of 11 cases (72.8 %) of chondrosarcomas showed a positive reaction for MMP-13, whereas two cases of normal cartilage were negative for this collagenase. As regard the clinicopathological parameters, there was no correlation between MMP-13 expression and sex, age and tumor site. While, there were significant associations between MMP-13 expression and both of mitotic counts and necrosis. On the other hand, there was a significant difference between low and high grade tumors (P < 0.05) regarding MMP-13 expression. Also, there was no significant correlation between MMP-13 expression in primary lesions and their local recurrence. CONCLUSION: MMP-13 is expressed in the majority of chondrosarcoma of the jaws. It is also noteworthy that the expression of MMP-13 may be related to tumor biological aggressiveness and used to aid in predicting patient's poor prognosis.