Intraductal Papillary Mucinous Neoplasm: New Insights Into Its Origin and Nomenclatures.

Background: Mucinous cells can be detected sporadically or may constitute the primary tumor component in salivary gland tumors, as observed in the intraductal papillary mucinous neoplasm (IPMN). This low-grade tumor is composed of mucinous columnar cells organized into papillary cystic structures. The present study aimed to compare the mucous cells in IPMN with mucous cells present in mucoepidermoid carcinoma (MEC) and papillary cystadenoma (PC).

Adenomatoid odontogenic tumor: Features of ameloblastic-like epithelial cells differentiation, secretion, and the nature of tumor cells products.

Background: This study aimed to investigate the differentiation of ameloblastic-like cells and the nature of the secreted eosinophilic materials in adenomatoid odontogenic tumors.

Methods: We studied histological and immunohistochemical characteristics of 20 cases using: cytokeratins 14 and 19, amelogenin, collagen I, laminin, vimentin, and CD34.

Results: Rosette cells differentiated into ameloblastic-like cells positioned face-to-face, displaying collagen I-positive material between them.

Estrogen Receptor, Progesterone Receptor, and HER-2 Expression in Recurrent Pleomorphic Adenoma.

Pleomorphic adenoma (PA) is the most common salivary gland neoplasm and, although mostly benign, recurrences, being called recurrent pleomorphic adenoma (RPA) and malignant transformation to carcinoma ex pleomorphic adenoma (CXPA), do occur. Recently, attention has been focused on molecular targeted cancer therapy in various tumors, including salivary gland tumors. The aim of this study was to investigate the role of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2) in PA, RPA, and CXPA.

The Challenging Diagnosis of Primordial Odontogenic Tumor.

Primordial odontogenic tumor (POT) is a benign mixed odontogenic tumor comprised of a loose connective tissue with a similar morphology with dental papilla and exhibiting in its periphery the presence of a columnar epithelium. POT occurs in young patients and typically is associated with an unerupted tooth, with the mandible being the main anatomic site of occurrence. The present manuscript is aimed at describing a new case of POT and reviewing the main biologic findings related to this odontogenic tumor.

Can non-collagenous proteins be employed for the differential diagnosis among fibrous dysplasia, cemento-osseous dysplasia and cemento-ossifying fibroma?

Differential diagnosis among fibrous dysplasias, cemento-ossifying fibromas and cemento-osseous dysplasias is difficult, since there is considerable overlap of histologic features, but also extremely important, since they differ greatly in etiology, clinical behaviour, prognosis and terapeuthic approach. There is no data about the use of immunohistochemistry, a viable and accessible technique, for this purpose. The objective of this study was to investigate, comparatively, the immunohistochemical expression of major non-collagenous proteins (osteonectin [ON], osteopontin [OP], bone sialoprotein [BSP] and osteocalcin [OC]) of mineralized tissue extracellular matrix in 22 cases of fibrous dysplasias, 16 of cemento-ossifying fibromas and 16 of cemento-osseous dysplasias.

Benign odontogenic ghost cell lesions revisited and new considerations on dysplastic dentin.

Objectives: This study aimed to revisit benign odontogenic ghost cell lesions (BOGCL) by hematoxylin and eosin staining and immunohistochemistry.

Materials And Methods: Thirty cases of calcifying odontogenic cyst (COC) and 6 cases of dentinogenic ghost cell tumor (DGCT) were selected for histopathological and immunohistochemical analysis. Sections stained for cytokeratin (K) 14, K-19, amelogenin, collagen type 1 (COL-1), and dentin matrix acidic phosphoprotein 1 (DMP-1) were evaluated using qualitative analysis.

Role of apoptotic, autophagic and senescence pathways in minor salivary gland adenoid cystic carcinoma.

Background: Adenoid cystic carcinoma (ACC) is a salivary gland malignancy with poor long-term survival, which warrants studies aimed at clarifying the pathogenesis of this disease in order to widen the scope of therapeutic options currently available. Alterations in regulatory mechanisms relating to vascular support, cell death and autophagy are important pathways for tumor growth in cancer. Thus, the present study aimed to access vascular supply, apoptosis, autophagy and cell senescence in ACC of minor salivary glands.

Comparison of p63/p40 Expression With Myoepithelial Markers in Minor Salivary Gland Tumors.

The present study aimed to compare the expression of p63/p40 with smooth muscle actin (SMA) and vimentin (VIM) by myoepithelial cells in minor salivary gland tumors. Fifty-two formalin-fixed paraffin-embedded samples of minor salivary gland tumors derived from intercalated duct (pleomorphic adenoma [PA], adenoid cystic carcinoma [ACC], epithelial-myoepithelial carcinoma [EMC], polymorphous adenocarcinoma [PAC], and secretory carcinoma [SC]) and 3 samples of minor salivary gland tumors derived from excretory duct (mucoepidermoid carcinoma [MEC]) were evaluated by means of immunohistochemistry. The data were analyzed qualitatively.

Microvessel density and cell proliferation in juvenile ossifying fibroma: A comparative study with central ossifying fibroma.

Considered as an aggressive counterpart of central ossifying fibroma (OF), juvenile ossifying fibroma (JOF) is a benign fibro-osseous neoplasm characterized by an unpredictable destructive behavior, elevated morbidity, mutilating treatment and high potential for local recurrences. The aim of this study is to compare the analysis for cell proliferation and vascular markers between JOF and OF. Cell proliferation index was measured by Ki-67 and Mcm-2 expression and microvessel density (MVD) was obtained by the immunoexpression of CD34/CD105.

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

The aim of the present study was to analyze the 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 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.

Factors that may influence polymorphous low-grade adenocarcinoma growth.

There is mounting evidence on the importance of some biological processes in tumor growth, such as vascular supply, apoptosis, autophagy, and senescence. We have investigated these processes in polymorphous low-grade adenocarcinoma (PLGA), in an attempt to identify those that are relevant for this particular lesion. We analyzed 31 cases of PLGA using immunohistochemistry to antibodies against CD34 and CD105 to detect blood vessels; against D2-40 to detect lymphatic vessels; against Bax, Bcl-2, and survivin to explore cell apoptosis; and against Beclin and LCB3 to investigate autophagy and against p21 and p16 to assess senescence.

Mammaglobin and DOG-1 expression in polymorphous low-grade adenocarcinoma: an appraisal of its origin and morphology.

Background: Polymorphous low-grade adenocarcinoma (PLGA) remains a diagnostic challenge for most pathologists due to its large spectrum of histological patterns. In this study, the expression of two new markers recently described for salivary gland tumors was studied in PLGA.

Methods: The morphology of 33 cases of PLGA was carefully evaluated using hematoxylin-and-eosin-stained sections and confirmed by immunohistochemistry for cytokeratin 7, vimentin, and S-100.

Dysregulation of the Rb pathway in recurrent pleomorphic adenoma of the salivary glands.

Pleomorphic adenoma (PA) is the most common salivary gland neoplasm, and while mostly benign, recurrences (RPA) and malignant transformation to carcinoma ex-PA (CXPA) do occur. Cell cycle proteins important in its tumorigenesis have been studied as markers for PA with a high risk of RPA or CXPA. The aim of the present study was to investigate cell cycle markers p-16, cyclin D1, CDK4, E2F, and retinoblastoma (Rb) in this context.

How do benign myoepithelial cells from in situ areas of carcinoma ex-pleomorphic adenoma favor tumor progression?

In this brief commentary, we have shown how the benign myoepithelial cells from in situ areas of carcinoma ex-pleomorphic adenoma from salivary gland can favor tumor progression, not only dying by autophagy/senescence phenomena, disrupting the physical barrier, but also providing fuel for tumor progression.

Multiple congenital granular cell epulis: case report and immunohistochemical profile with emphasis on vascularization.

Congenital granular cell epulis is a rare benign soft tissue lesion arising from the alveolar ridge in neonates. A rare case of multiple congenital granular cell epulis is reported, alongside a description of its vascular immunohistochemical profile. A female newborn presented with two exophytic pedunculated red nodules located on the alveolar ridge between the future eruption sites of the incisors and canines of the mandible and maxilla.

The role of FGF-2/HGF and fibronectin matrix on pleomorphic adenoma myoepithelial cell morphology and immunophenotype: an in vitro study.

Myoepithelial cells play a central role in glandular tumors, regulating the progression of in situ to invasive neoplasias, with the tumor microenvironment being shown to be involved in both initiation and progression. This study aimed to analyze the in vitro effects of fibroblast growth factor-2 (FGF-2) and hepatocyte growth factor (HGF) in myoepithelial cells under the influence of the fibronectin matrix extracellular protein. Benign myoepithelial cells were obtained from pleomorphic adenoma and cultured on a fibronectin substratum.

Tooth alterations in areas of bisphosphonate-induced osteonecrosis.

Objective: Osteonecrosis of the jaw is a potential side effect when using bisphosphonates. Most studies on the effects of bisphosphonates on teeth have been conducted in vitro or in animal models of tooth development. Therefore, the aim of this study was to describe alterations found in human teeth extracted from areas of bisphosphonate-induced osteonecrosis.

Brazilian orthodontists and the legal issues involving their professional activity: A legal and behavioral proposal.

Objective: The aim of this study was to review the use of orthodontic records (OTR's) by Brazilian orthodontists and propose a behavioral approach from a legal point of view, drawing on their interpersonal relationship with their patients.

Methods: A statistical cross-analysis was performed to compare five groups. A sixth group was created comprising the intersection of the responses provided by the five aforementioned groups.

Intraoral adult rhabdomyoma: a case report.

A case of adult rhabdomyoma is reported. The lesion is a rare benign tumor of skeletal muscle origin which occurs predominantly in the head and neck region. In the present case, the clinical diagnosis favored a benign salivary gland tumor.

Polymorphous low-grade adenocarcinoma: an analysis of epidemiological studies and hints for pathologists.

Background: This study is an analysis of the prevalence of polymorphous low grade adenocarcinoma (PLGA) in epidemiological surveys of salivary tumors published in the English language from 1992 to 2012.

Methods: These surveys included studies from different researchers, countries and continents. The 57 surveys for which it was possible to calculate the percentage of PLGAs among all malignant minor salivary gland tumors (MMSGT) were included in this review.

In vitro cytokine expression in in situ-like areas of malignant neoplasia.

Objectives: The myoepithelial cells exert important effects regulating the transition of an in situ to an invasive carcinoma. This cell has been associated with a tumour suppressor phenotype due to its ability to inhibit tumour growth as well as its immunomodulatory role in cancer behaviour.

Design: In order to correlate the cancer cell growth and the role of cytokines in regulating the neoplastic process, we have attempted to simulate an in vitro model of tumorigenesis, which mimics a situation where in situ neoplastic cells of carcinoma are surrounded by benign myoepithelial cells from pleomorphic adenoma.

Trabecular juvenile ossifying fibroma with aneurysmal bone cyst: a rare presentation.

Juvenile ossifying fibroma is an uncommon, benign, bone-forming neoplasm that is distinguished from other fibro-osseous lesions primarily by its age of onset, clinical presentation, and potential behavior. It mainly occurs in juveniles and has a slight male predilection and more aggressive behavior than a common ossifying fibroma. There are 2 distinct histopathological variants of this lesion: (1) psammomatoid pattern and (2) trabecular pattern.

In vitro influence of the extracellular matrix in myoepithelial cells stimulated by malignant conditioned medium.

In order to investigate the role of myoepithelial cell and tumor microenvironment in salivary gland neoplasma, we have performed a study towards the effect of different extracellular matrix proteins (basement membrane matrix, type I collagen and fibronectin) on morphology and differentiation of benign myoepithelial cells from pleomorphic adenoma cultured with malignant cell culture medium from squamous cell carcinoma. We have also analyzed the expression of α-smooth muscle actin (α-SMA) and FGF-2 by immunofluorescence and qPCR. Our immunofluorescence results, supported by qPCR analysis, demonstrated that α-SMA and FGF-2 were upregulated in the benign myoepithelial cells from pleomorphic adenoma in all studied conditions on fibronectin substratum.

FGF-2, TGFbeta-1, PDGF-A and respective receptors expression in pleomorphic adenoma myoepithelial cells: an in vivo and in vitro study.

Unlabelled: Myoepithelial cells have an important role in salivary gland tumor development, contributing to a low grade of aggressiveness of these tumors. Normal myoepithelial cells are known by their suppressor function presenting increased expression of extracellular matrix genes and protease inhibitors. The importance of stromal cells and growth factors during tumor initiation and progression has been highlighted by recent literature.