Ki-67 Prognostic Value in Different Histological Grades of Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma

Introduction: Abnormal cell proliferation appears to be a possible predictor of tumorigenesis, Ki-67 protein expression is closely related to the cell proliferation and could be used as a biomarker for the growth in the most of human tumors. The aim of the study: Investigating of Ki-67 expression in the pathological grades of oral epithelial dysplasia and oral squamous cell carcinomas. Materials and Methods: The sample consisted of 30 formalin-fixed, paraffin-embedded specimens of oral epithelial dysplasia (OED), 30 other of oral squamous cell carcinomas (OSCC), and 10 normal oral epithelium (NOE) were conventionally stained with hematoxylin and eosin and immunohistochemically stained with Ki-67 monoclonal antibody. Results: Expression of Ki-67 was restricted to the basal layers in the normal oral epithelium whereas Ki-67 positive cells in oral epithelial dysplasia (OED) were located in the basal, suprabasal and spinous layers, Ki-67 expression was increased in high-risk cases. Ki-67 positive cells in well-differentiated (OSCC) were located mainly in the periphery of the tumor nests, in moderately-differentiated (OSCC) were located in both peripheral and part of a center of the tumor nests whereas it was diffused in most of the Poorly-differentiated (OSCC). Statistical analysis indicated a significant difference between the expression in (OED) and (NOE), (OSCC) and (NOE), and no differences between (OED) and (OSCC). Conclusion: This study has concluded that Ki-67 antigen could be used as a marker for the histological grading of OED and OSCC, Expression of Ki 67 increased according to the severity of oral epithelial dysplasia.

p53 Overexpression in Oral Mucosa in Relation to Shisha Smoking in Syria and Lebanon

Introduction: Shisha (waterpipe) smoking is becoming a very prevalent form of tobacco consumption in the Middle east and use is growing over the world. Smoking-related malignancies have a high genome-wide burden of mutations, including examples in the gene encoding p53. Aims: To investigate alterations in p53 immunohistochemical expression in the normal, pre-malignant, malignant oral mucosa in relation to Shisha smoking habits. Materials and Methods: A total of 105 paraffin embedded tissue sections of OSCCs (52 smokers,53 non-smokers), 96 of premalignant lesions (48 smokers,48 non-smokers) and 60 normal oral mucosa. Some 30 patients with a history of Shisha smoking daily for more than 5 years were also investigated for mutant expression of p53. Tissue samples were considered positive for p53 staining when any positive cells of epithelial origin could be detected. Results: The majority (74.3%) of oral squamous cell carcinomas showed positive staining for p53 expression (83.1% and 65.5% with Shisha smokers and non-smokers, respectively). In the 96 premalignant lesions, about 23% from non-smokers and 41.7% from smokers showed p53 positivity. In normal epithelium, P53 positive cells were noted in 6.6% of non-smokers and 16.6% of smokers. Positive correlations with Shisha smoking were evident for the following groups: WDOSCC, MDOSCC, mild dysplasia G1, moderate dysplasia G2 and in normal mucosa using Student's t- test, P value<0.05. Conclusion: These results strongly suggest that p53 mutations are associated with Shisha smoking in OSCC, pre-malignant lesions and normal mucosa of the oral cavity.

Amelogenin is a Potential Biomarker for the Aggressiveness in Odontogenic Tumors

Amelogenin (AMEL), the major structural protein of the enamel organic matrix, constitutes more than 90% of the enamel's protein content, Aberrations of amelogenin are thought to be involved in the oncogenesis of odontogenic epithelium. The expression of amelogenin is possibly an indicator of differentiation of epithelial cells in the odontogenic tumors. Aim of the study: Investigating the expression of amelogenin in some odontogenic tumors, using an anti-amelogenin polyclonal antibody, and then compare it with AMEL expression in tooth buds as control. Materials and Methods: study sample consisted of 10 formalin-fixed, paraffin- embedded specimens of ameloblastoma, 10 Keratocystic odontogenic tumors, and 10 tooth buds were conventionally stained with hematoxylin-eosin and immunohistochemically with AMEL polyclonal antibody. Results: All of the odontogenic tumors expressed AMEL in the epithelial component, Intensity of expression in ameloblastoma and Keratocystic odontogenic tumor was lower, compared with tooth buds, Statistical analysis indicated a significant differences between the tumors and tooth buds. Conclusion: Amelogenin can be used as a marker for odontogenic epithelium, and the expression of amelogenin is possibly an indicator of epithelial cells differentiation in the odontogenic tumors, and therefore in prediction of the histological behavior of odontogenic tumors.

CCR7 and CXCR4 Expression in Primary Head and Neck Squamous Cell Carcinomas and Nodal Metastases ­ a Clinical and Immunohistochemical Study

Background: Squamous cell carcinomas (SCCs) are common head and neck malignancies demonstrating lymph node LN involvement. Recently chemokine receptor overxpression has been reported in many cancers. Of particular interest, CCR7 appears to be a strong mediator of LN metastases, while CXCR4 may mediate distant metastases. Any relations between their expression in primary HNSCCs and metastatic lymph nodes need to be clarified. Aims: To investigate CCR7 andCXCR4 expression in primary HNSCCs of all tumor sizes, clinical stages and histological grades, as well as involved lymph nodes, then make comparisons, also with control normal oral epithelium. Materials and Methods: The sample consisted of 60 formalin-fixed, paraffin-embedded specimens of primary HNSCCs, 77 others of metastasi-positive lymph nodes, and 10 of control normal oral epithelial tissues. Sections were conventionally stained with H&E and immunohistochemically with monoclonal anti-CCR7 and monoclonal anti-CXCR4 antibodies. Positive cells were counted under microscopic assessment in four fields (X40) per case. Results: There was no variation among primary HNSCC tumors staining positive for CCR7 and CXCR4 with tumor size of for CCR7 with lymph node involvement. However, a difference was noted between primary HNSCC tumors stained by CXCR4 with a single as compared to more numerous node involvement. CXCR4 appear to vary with the clinical stagebut no links were noted with histological grades. Staining for primary HNSCC tumors and metastatic lymph nodes correlated.

Epidemiological Characteristics of Retinoblastoma in Children Attending Almouassat University Hospital, Damascus, Syria, 2012-2016

Retinoblastoma (Rb) is a malignant tumor that originates from the developing retina. Diagnosis is based on clinical signs and symptoms and usually children under the age of five years are affected. Early diagnosis and treatment of Rb and non-ocular tumors can reduce morbidity and increase longevity. Treatment in the early stages may allow a good prognosis and salvage of visual function.The aim of this study is to present descriptive epidemiological aspects of retinoblastomas in children seen at Almouassat University Hospital (AUH) in Damascus, Syria from 1 January 2012 to 31 October 2016In this retrospective, observational hospital survey, medical records of 37 retinoblastoma cases were reviewed. The male/female (M/F) ratio was 1.6. The most frequent presenting sign was leukocoria (56.7%) and 81% of cases were diagnosed between the ages of 4 months and 3 years. More than 73% of cases were diagnosed early at stages I and II.

Lack of Effects of Recombinant Human Bone Morphogenetic Protein2 on Angiogenesis in Oral Squamous Cell Carcinoma Induced in the Syrian hamster Cheek Pouch.

Recombinant human bone morphogenetic protein2 (rhBMP2 ), a member of the TGF? family, has been used widely in recent years to regenerate defects of the maxillary and mandible bones. Such defects are sometimes caused by resection of oral squamous cell carcinoma (OSCC) yet the biologic effects of rhBMP2 on these carcinomas are not fully clear. The objective of this study was to determine histologically whether rhBMP2 produces adverse effects on angiogenesis during induction of OSCC, a biologic process critical for tumor formation in an experimental model in the buccal pouch of golden Syrian hamsters. Buccal cavities were exposed to painting with 0.5% DMBA in liquid paraffin three times a week for 14 weeks, then biopsies were taken. Division was into 2 groups: a study group of 10 hamsters receiving 0.25?g/ml of rhBMP2 in the 3rd and 6th weeks; and a control group of 10 hamsters which did not receive any additional treatment. VEGF expression and microvessel density were measured but no differences were noted between the two groups. According to this study, rhBMP2 does not stimulate angiogenesis during induction of OCSSs.

Recombinant Human Bone Morphogenetic Protein-2 in Development and Progression of Oral Squamous Cell Carcinoma.

Bone morphogenetic proteins (BMPs), belonging to the transforming growth factor-ß superfamily, regulate many cellular activities including cell migration, differentiation, adhesion, proliferation and apoptosis. Use of recombinant human bone morphogenic protein?2 (rhBMP?2) in oral and maxillofacial surgery has seen a tremendous increase. Due to its role in many cellular pathways, the influence of this protein on carcinogenesis in different organs has been intensively studied over the past decade. BMPs also have been detected to have a role in the development and progression of many tumors, particularly disease-specific bone metastasis. In oral squamous cell carcinoma - the tumor type accounting for more than 90% of head and neck malignancies- aberrations of both BMP expression and associated signaling pathways have a certain relation with the development and progression of the disease by regulating a range of biological functions in the altered cells. In the current review, we discuss the influence of BMPs -especially rhBMP-2- in the development and progression of oral squamous cell carcinoma.

Immunohistochemical assessment of E-cadherin and ß-catenin in the histological differentiations of oral squamous cell carcinoma.

The aim of this study was to establish the expression and localization of E-cadherin and ß-catenin in oral squamous cell carcinomas (OSCC) so that we could correlate the findings with prognostic-relevant histopathological variables. E-cadherin and ß-catenin expression in normal oral epithelia and in oral squamous cell carcinomas was examined immunohistochemically, and associations with histopathological differentiation and prognosis were then analyzed in 33 patients who had been operated on for OSCC. E-cadherin expression was found in (82%) of the squamous cells of well differentiated OSCC, (61%) of moderately differentiated and (39%) of poorly differentiated. E-cadherin expression was significantly associated with histological grade (p=0.000). No nuclear staining was detected. In (19.5%) of the cells E-cadherin localized in the cytoplasm, with no correlation to the histological grade (p=0.106). ß-Catenin expression was found in 87% of the squamous cells of well differentiated OSCC, 67% of moderately differentiated and 43% of poorly differentiated, the expression was significantly associated with histological grade (p=0.000). the nuclear ß-Catenin expression appeared in 3.3% of the cells and it was correlated to the histological grade (p=0.000). In (23.5%) of the cells ß-Catenin localized in the cytoplasm, with correlation to the histological grade (p=0.002). According to this study the expression of ß-catenin and E-cadherin were independent prognostic factors for histological grade. E-cadherin was closely linked to ß-catenin expression in OSCC (p=0.000) and to tumor differentiation. That reflects a structural association and the role of both in tumor progression.