Oral lymphatic malformations: A multicenter study of 208 cases and literature review.

BACKGROUND: To evaluate the frequency and analyze demographic and clinical characteristics of individuals with a histopathological diagnosis of oral lymphatic malformations (OLMs). METHODS: A multicenter study was performed, collecting biopsy record data from a consortium of Brazilian Oral and Maxillofacial Pathology Centers. A review was also conducted to compare this data with cases already available in the literature. RESULTS: This study retrieved 208 cases of OLM in the multicenter study and 1035 cases in the literature review. In both, OLMs affected male and female individuals equally, with the most affected site being the tongue. Individuals ≥60 years of age were uncommonly affected. Symptomatic and larger lesions were more commonly reported in the literature review. CONCLUSIONS: This study comprises the largest sample of OLMs to date. OLMs are rare conditions, without sex predilection. The elderly proved to be less frequently affected, and the tongue is the most commonly affected site.

Oral lesions in children/teenagers: a cross-sectional study of 225 reports in a pathology service in Amazon.

BACKGROUND: Epidemiologic studies of oral lesions in pediatric patients are scarce in Brazil, and especially in the northern region of the country. We aim to describe the distributions of oral lesions in children and teenagers diagnosed in a Pathology service of Amazon for over 15 years. METHODS: The oral pathology files were retrospectively retrieved from January 2002 to December 2016 of patients younger than 18 years old at the Pathology Service of the Federal University of Amazonas. Patient information such as gender, age, race, aspect of the lesion, anatomical site, and histological type was compiled from the file of requisitions and histopathologic reports. Oral lesions were subdivided into 11 categories. RESULTS: From a total of 2437 histopathological oral reports, 225 of them were from children. Of these, 125 (55.6%) were from male patients and 100 (44.4%) from female patients with a median age of 13 years. Of the 11 categories of oral pathologies, the one of the highest numbers was salivary gland disease (N.=50, 22.2%) with the subtype mucocele (N.=41, 18.22%) as the most prevalent followed by Miscellaneous pathology (N.=27, 12%) with the predominance of the subtype granulation tissue (N.=11, 4.89%) and finally Odontogenic tumors (N.=26, 11.6%) in third place, with odontoma (N.=16, 7.11%) as the most prevalent subtype. CONCLUSIONS: Mucocele was the most prevalent lesion found, showing that a traumatic etiology is likely to be the most common situation in children and teenagers, while neoplastic lesions are generally rare.

miR-494 represses HOXA10 expression and inhibits cell proliferation in oral cancer.

OBJECTIVES: miR-494 was identified as a candidate of the most significantly underexpressed microRNAs (miRNAs) in our oral cancer screen. The aim of this study was to validate whether miR-494 has a functional role in oral cancer. METHODS: Quantitative miRNA analyses were performed on oral tumor RNA and oral cancer cell lines. HOXA10 was selected for further analysis based on bioinformatics analysis of miR-494 targets and a previous report of overexpression of HOXA10 in oral cancer. Transient transfection of miRNA-mimic and inhibitor were performed in SCC-25 (tongue), CAL 27 (tongue), and FaDu (pharynx) cancer cells and regulation of HOXA10 by miR-494 was investigated. Dual luciferase assay was used to verify the interaction between miR-494 and HOXA10 in reporter cells. The effect of miR-494 on cell proliferation was examined. RESULTS: Our data showed that miR-494 was underexpressed whereas HOXA10 was overexpressed in oral cancer compared to normal tissues. An inverse correlation between miR-494 and HOXA10 was observed in the human tissues (p<0.05). Transient transfection of miR-494 in all cancer cell lines significantly reduced the expression of HOXA10 mRNA. The luciferase reporter that contains the 3'UTR of HOXA10 showed a significantly reduced luciferase activity by miR-494 indicating a direct interaction between HOXA10 and miR-494. Significant reduction in cell proliferation was demonstrated in tongue cancer cells transfected with miR-494. CONCLUSION: miR-494 repressed the expression of HOXA10 and also reduced the proliferation of oral cancer cells. These data give more evidence of the role of miR-494 as a tumor suppressor miRNA in oral cancer.