Oral pigmented lesions: a retrospective analysis from Brazil / Lesiones pigmentadas orales: un análisis retrospectivo desde Brasil

Background: Pigmented lesions are uncommon in the oral mucosa, and studies investigating the incidence andtypes of these lesions are desired to improve the diagnostic knowledge of clinicians. The aim of this study was toanalyze the distribution of oral pigmented lesions in a Brazilian population.Material and Methods: A retrospective descriptive cross-sectional study was performed. Oral pigmented lesionswere retrieved from the files of two oral and maxillofacial pathology services from Brazil over a 45-year period(1974-2019). The clinical data and the diagnoses of each case were retrieved and included in a Microsoft Excel®database.Results: From 77.074 lesions diagnosed in this period, 761 (0.99%) represented pigmented lesions of the oralmucosa, including 351 (46.1%) melanocytic and 410 (53.9%) non-melanocytic lesions, with a higher incidence infemales (73.2%) between the fourth and seventh decades of life. Amalgam tattoo (53.6%) represented the most common lesion, followed by melanotic macule (18.3%) and racial pigmentation (10.8%). Other pigmented lesionsincluded nevus (9.9%), post-inflammatory pigmentation (3%), melanoma (2.1%), melanoacanthoma (1.4%), smoker'smelanosis (0.4%), drug-induced pigmentation (0.3%), and melanotic neuroectodermal tumor of infancy (0.1%). Thebuccal mucosa was the most commonly affected site (25.2%), followed by the alveolar ridge (14.5%), and gingiva(11.8%).Conclusions: The current findings were similar to previous studies with minor differences due methodology andcharacteristics of the services from where lesions were retrieved. The knowledge of these data may contribute to abetter understanding of oral pigmented lesions and assist clinicians to better recognize and manage them.(AU)

An in vitro study showing the three-dimensional microenvironmentinfluence over the behavior of head and neck squamous cell carcinoma

Objectives: The Head and Neck Squamous Cell Carcinoma (HNSCC) ranks sixth worldwide. The mechanisms of growth, invasion and metastasis of this pathology are extensively studied and generally related to specific variations in signaling pathways like the PI3K-Akt; however most of these competent studies have been performed bidimensionally, which may hide important questions. This study sought to analyze the influence of the microenvironment upon the behavior of HNSCC. Study Design: The status of pAkt, NF-KappaB and Cyclin D1 proteins was accessed through immunofluorescence and western blot methods in HNSCC cell lines originating from tongue, pharynx and metastatic lymph node when submitted to a three-dimensional culture model utilizing a matrix system. A bidimensional culture model (monolayer) was used as control. Results: The HNSCC cell lines cultured three-dimensionally exhibited a growth pattern characterized by small isolated islands, different from the control group. When the three-dimensional model was applied, two of the studied cell lines showed the same expression pattern as the bidimensional model regarding nuclear or cytoplasmatic localization, as well as reduction of all protein levels; however, the cell line originated from tongue, which specially has the epidermal growth factor receptor constitutively activated, demonstrated nuclear translocation of pAkt and also an increase in the levels of Cyclin D1. Conclusions: The results suggest the influence of the microenvironment upon the behavior of HNSCC cells due to the changed expression of proteins related to tumor growth and cellular invasion. Furthermore, intrinsically genetic conditions also played important roles over the cells, despite the culture model employed (AU)

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An in vitro study showing the three-dimensional microenvironment influence over the behavior of head and neck squamous cell carcinoma.

OBJECTIVES: The Head and Neck Squamous Cell Carcinoma (HNSCC) ranks sixth worldwide. The mechanisms of growth, invasion and metastasis of this pathology are extensively studied and generally related to specific variations in signaling pathways like the PI3K-Akt; however most of these competent studies have been performed bidimensionally, which may hide important questions. This study sought to analyze the influence of the microenvironment upon the behavior of HNSCC. STUDY DESIGN: The status of pAkt, NF-κB and Cyclin D1 proteins was accessed through immunofluorescence and western blot methods in HNSCC cell lines originating from tongue, pharynx and metastatic lymph node when submitted to a three-dimensional culture model utilizing a matrix system. A bidimensional culture model (monolayer) was used as control. RESULTS: The HNSCC cell lines cultured three-dimensionally exhibited a growth pattern characterized by small isolated islands, different from the control group. When the three-dimensional model was applied, two of the studied cell lines showed the same expression pattern as the bidimensional model regarding nuclear or cytoplasmatic localization, as well as reduction of all protein levels; however, the cell line originated from tongue, which specially has the epidermal growth factor receptor constitutively activated, demonstrated nuclear translocation of pAkt and also an increase in the levels of Cyclin D1. CONCLUSIONS: The results suggest the influence of the microenvironment upon the behavior of HNSCC cells due to the changed expression of proteins related to tumor growth and cellular invasion. Furthermore, intrinsically genetic conditions also played important roles over the cells, despite the culture model employed.