Effect of epithelial growth factor on matrix metalloproteinase-2 and E-cadherin/β-catenin expression in an in situ model of tumorigenesis

The aim of the present study was to analyze the in vitro effect of various doses of epidermal growth factor (EGF; 5 and 10 ng/ml) on matrix metalloproteinase-2 (MMP-2) secretion and E-cadherin/β-catenin expression by co-cultured cells that mimic an in situ carcinoma ex-pleomorphic adenoma, where benign myoepithelial cells from a pleomorphic adenoma surround malignant epithelial cells. EGF was supplemented in various doses and the effects were evaluated following four days of cell culture. ELISA was performed to determine MMP-2 secretion levels. Gene expression for E-cadherin and β-catenin was analyzed using quantitative polymerase chain reaction. The results revealed that E-cadherin expression decreased when the cells were supplemented with 5 ng/ml EGF. ELISA results indicated that MMP-2 secretion increased when EGF was supplemented at concentrations of 5 and 10 ng/ml. The present findings demonstrated that EGF may be involved in the epithelial-mesenchymal transition process via altering the E-cadherin/β-catenin complex and increasing MMP-2 secretion, which may then favor the dissolution of the basement membrane to the benefit of malignant cell clusters, contributing to the development of an invasive phenotype in this in vitro model of tumorigenesis.

Epidemiological survey of oral and maxillofacial complex biopsies: 13 year retrospective study

Objective: To conduct a retrospective study through epidemiological survey of the biopsies of oral cavity performed at the Center of Pathology, Cytology, and Cytopathology– CEPACC in Parnaíba-PI, from 1998 to 2011. Material and Methods: One hundred and thirty-nine referrals and reports were analyzed by evaluating the group and prevalence of oral lesions, anatomical location, and distribution in relation to type, gender, and age. Results: Females (52%) showed the greatest prevalence, observing more cases in the age range of 41 to 60 years. The lip was the preferable location of the analyzed lesions. The groups of the lesions in salivary glands (17%), malignant tumors of epithelial origin, benign tumors of conjunctive origin, premalignant lesions of epithelial origin, and odontogenic cysts were the most common lesions. Considering the isolated lesions, squamous cell carcinoma was the most frequent. We observed a greater preference for salivary gland lesions, although great diversity of clinical cases was found. Conclusion: The reported lesions occurred mostly in adult females and in groups with salivary gland diseases. KeywordsEpidemiology; Oral lesions; Biopsy; Oral Pathology; Diagnosis. 

Root resorption and ankylosis associated with guided tissue regeneration

BACKGROUND

Root resorption and ankylosis have been reported rarely as sequelae to guided tissue regeneration (GTR). The authors describe a clinical case of root resorption following GTR that involved the use of a bioabsorbable membrane.

CASE DESCRIPTION

Two years after GTR was performed on a Class II furcation defect, the clinical examination revealed root resorption reaching the pulp chamber. The furcation defect was filled with epithelium and connective tissue, which contained inflammatory infiltrate and fragments of the membrane. The authors also observed areas of the tooth that exhibited points of ankylosis and root resorption.

CLINICAL IMPLICATIONS

Clinical trials have reported favorable clinical and histologic results with GTR. However, this case report, along with other case reports and studies in animals, suggests a high risk of root resorption and ankylosis after GTR, which could limit the indications for this technique.

Peripheral clear cell variant of calcifying epithelial odontogenic tumor: Report of a case and immunohistochemical investigation

A case of peripheral calcifying epithelial odontogenic tumor, clear cell variant, located on the right gingival maxilla of a 48-year-old woman, presenting as a 2.0-cm solitary, firm nodule was studied. Microscopically, it was composed of polyhedral and clear epithelial cells associated with amyloid-like deposition. The clear epithelial cells exhibited granules that were positive for periodic acid-Schiff, and the amyloid-like deposit stained with Congo red showed a green birefringence in the polarized light. Polyhedral and clear epithelial cells were immunopositive for AE1/AE3 and cytokeratin 14. Immunoexpression of fibronectin and types I and III collagen were different between the amyloid-like deposits and the connective tissue stroma. Tenascin surrounded epithelial cells located inside the amyloid-like deposits. Laminin and type IV collagen were immunodetectable around the strands, cords, and nests of epithelial cells. This report represents the seventh case of peripheral calcifying epithelial odontogenic tumor, clear cell variant.