N-acylhydrazone derivative modulates cell cycle regulators promoting mitosis arrest and apoptosis in estrogen positive MCF-7 breast cancer cells.

Breast cancer is the leading cause of cancer death among women worldwide. About 75% of all diagnosed cases are hormone-positive, which are treated with hormone therapy. However, many patients are refractory or become resistant to the drugs used in therapeutic protocols. In this scenario, it is essential to identify new substances with pharmacological potential against breast cancer. VEGFR2 inhibitors are considered promising antitumor agents not only due to their antiangiogenic activity but also by inhibiting the proliferation of tumor cells. Thus, the present study aimed to evaluate the effects of N-acylhydrazone derivative LASSBio-2029 on the proliferative behavior of MCF-7 cells. We observed a promising antitumor potential of this substance due to its ability to modulate critical cell cycle regulators including mitotic kinases (CDK1, AURKA, AURKB, and PLK1) and CDK inhibitor (CDKN1A). Increased frequencies of abnormal mitosis and apoptotic cells were observed in response to treatment. A molecular docking analysis predicts that LASSBio-2029 could bind to the proto-oncoprotein ABL1, which participates in cell cycle control, interacting with other controller proteins and regulating centrosome-associated tubulins. Finally, we created a gene signature with the downregulated genes, whose reduced expression is associated with a higher relapse-free survival probability in breast cancer patients.

Piperine-Chlorogenic Acid Hybrid Inhibits the Proliferation of the SK-MEL-147 Melanoma Cells by Modulating Mitotic Kinases.

Melanoma is considered the most aggressive form of skin cancer, showing high metastatic potential and persistent high mortality rates despite the introduction of immunotherapy and targeted therapies. Thus, it is important to identify new drug candidates for melanoma. The design of hybrid molecules, with different pharmacophore fragments combined in the same scaffold, is an interesting strategy for obtaining new multi-target and more effective anticancer drugs. We designed nine hybrid compounds bearing piperine and chlorogenic acid pharmacophoric groups and evaluated their antitumoral potential on melanoma cells with distinct mutational profiles SK-MEL-147, CHL-1 and WM1366. We identified the compound named PQM-277 (3a) to be the most cytotoxic one, inhibiting mitosis progression and promoting an accumulation of cells in pro-metaphase and metaphase by altering the expression of genes that govern G2/M transition and mitosis onset. Compound 3a downregulated FOXM1, CCNB1, CDK1, AURKA, AURKB, and PLK1, and upregulated CDKN1A. Molecular docking showed that 3a could interact with the CUL1-RBX1 complex, which activity is necessary to trigger molecular events essential for FOXM1 transactivation and, in turn, G2/M gene expression. In addition, compound 3a effectively induced apoptosis by increasing BAX/BCL2 ratio. Our findings demonstrate that 3a is an important antitumor candidate prototype and support further investigations to evaluate its potential for melanoma treatment, especially for refractory cases to BRAF/MEK inhibitors.

Immunomodulatory Effect of Polysaccharides from the Mushroom-Forming Basidiomycete Gymnopilus imperialis (Agaricomycetes, Basidiomycota).

Gymnopilus consists of a widely distributed genus of basidiomycetes, especially in tropical regions of the world, such as Japan, Australia, Paraguay, and Brazil. This genus biosynthesizes interesting bioactive compounds, such as sesquiterpenoids, oligoisoprenoids, styrylpyrones, and lectins. In the present study, the aqueous extract of the basidiomata of Gymnopilus imperialis (Basidiomycota, Agaricomycetes, Agaricales, Hymenogastraceae) was obtained by using the accelerated solvent extraction (ASE) technique, followed by the precipitation of polysaccharide fraction with ethanol. Further purification by freeze-thawing processes, Fehling solution precipitation, and membrane dialysis with different pore sizes yield three main polysaccharide fractions (Gi-MRSW, Gi-PFME, and Gi-SFME). According to monosaccharide composition and 13C-NMR data, the Gi-MRSW and Gi-SFME fractions showed to be composed mainly of ß-glucans and Gi-PFME by a heterogalactan. Moreover, the immunomodulatory potential of Gi-MRSW was evaluated using RAW 264.7 murine macrophage as a study model. The nitric oxide production was significantly increased in treated samples, and the expression of inducible nitric oxide synthase (iNOS) showed that the fraction Gi-MRSW from G. imperialis induces the M1 polarization phenotype.

Photobiomodulation enhances the Th1 immune response of human monocytes.

This study aims to evaluate the effects of photobiomodulation (PBM) on human monocytes, assessing the oxidative burst and ultimate fungicidal potential of these cells, as well as the gene expression at the mRNA level of CD68, CD80, CD163, CD204, IL-6, TNF-α and IL-10 in derived macrophages. Primary cultures of human monocytes were irradiated with an InGaAlP (660 nm)/GaAlAs (780 nm) diode laser (parameters: 40 mW, 0.04 cm2, 1 W/cm2; doses: 200, 400 and 600 J/cm2). Cells were submitted to the chemiluminescence assay, and a microbicidal activity assay against Candida albicans was performed. Reactive oxygen species (ROS) and nitric oxide (NO) production were measured, and cell viability was assessed by the exclusion method using 0.2% Trypan blue reagent. Irradiated monocytes were cultured for 72 h towards differentiation into macrophages. Total RNA was extracted, submitted to reverse transcription and real-time PCR. The results were analysed by ANOVA and the Tukey test (α = 0.05). Irradiated monocytes revealed a significant increase in their intracellular and extracellular ROS (P < 0.001). The 660 nm wavelength and 400 J/cm2 dose were the most relevant parameters (P < 0.001). The fungicidal capacity of the monocytes was shown to be greatly increased after PBM (P < 0.001). PBM increased the expression of TNF-α (P = 0.0302) and the production of NO (P < 0.05) and did not impair monocyte viability. PBM induces a pro-inflammatory Th1-driven response in monocytes and macrophages.

Development and Evolution of a Diagnostic and Oral Pathology Service in a Southeast Brazilian State / Desenvolvimento e Evolução de um Serviço de Diagnóstico e de Patologia Bucal em um Estado do Sudeste Brasileiro / Desarrollo y Evolución de un Servicio de Diagnóstico y Patología Oral en un Estado del Sudeste Brasileño

Introduction: Oral squamous cell carcinoma (OSCC) is one of the most frequent cancers whose main causes are preventable because oral cavity is easily accessible for examination. OSCC involves many steps from the diagnosis until treatment which can result in late diagnosis and worst prognosis. Objective: Development and evolution of a Stomatology and Oral Pathology Service at the Federal University of Alfenas addressing early diagnosis and management of oral lesions. Method: Retrospective study developed with the files from 1998 to 2019. Data from all the cases diagnosed as oral malignancies were collected and the demographical, clinical, and microscope diagnosis were included. Results: 270 (84.64%) OSCC were found among 8,952 histopathological diagnoses. The patients age ranged from 24 to 94 years (mean 59.7±13.1 years), and more frequent in the sixth (32.3%) and seventh (26%) decades of life. Men were 2.5 times more affected than women. Most of patients were Caucasian (74.8%), and users of tobacco and alcohol. Over the years, there was an increase in the number of cases diagnosed and expansion of the area covered by the Service. Conclusion: The Dental Clinic (Stomatology) and Oral Pathology Laboratory has been playing an important role for the establishment and improvement of the healthcare system to the local population, mainly in rural áreas

Introdução: O carcinoma de células escamosas (CEC) de boca está entre os cânceres mais frequentes. Suas principais causas são evitáveis, pois a cavidade oral é uma área de fácil acesso para exame. No entanto, desde o estabelecimento do diagnóstico até o tratamento final dos pacientes, o CEC envolve muitas etapas e pode resultar em diagnóstico tardio e, portanto, em pior prognóstico para os pacientes. Objetivo: Apresentar o desenvolvimento e a evolução de um Serviço de Estomatologia e Patologia Oral da Universidade Federal de Alfenas, que tem como foco o diagnóstico precoce e o tratamento de lesões bucais. Método: Estudo retrospectivo com os prontuários de 1998 a 2019. Foram coletados dados de todos os casos diagnosticados como malignidades orais e incluídos os diagnósticos demográficos, clínicos e microscópicos. Resultados: Entre 8.952 diagnósticos histopatológicos realizados, 270 (84,64%) eram CCE. A idade dos pacientes variou de 24 a 94 anos (média 59,7±13,1 anos), sendo mais frequente na sexta (32,3%) e sétima (26%) décadas de vida. Os homens foram 2,5 vezes mais afetados do que as mulheres. A maioria dos pacientes era branca (74,8%) e o uso de tabaco e álcool, frequente. Ao longo dos anos, houve um aumento do número de casos diagnosticados, bem como uma ampliação da área de cobertura do Serviço. Conclusão: O Serviço de Estomatologia e Patologia Oral tem desempenhado um papel importante na implantação e melhoria do sistema de saúde da população local, principalmente nas Regiões interioranas e em áreas rurais

Introducción: El carcinoma de células escamosas (CCE) de boca se encuentra entre los cánceres más frecuentes. Sus principales causas se pueden prevenir ya que la cavidad bucal es un área de fácil acceso para su examen. Sin embargo, desde el establecimiento del diagnóstico hasta el tratamiento final de los pacientes, la CEC implica muchos pasos y puede resultar en un diagnóstico tardío y, por lo tanto, un peor pronóstico para los pacientes. Objetivo: Presentar el desarrollo y evolución de un Servicio de Estomatología y Patología Bucal de la Universidad Federal de Alfenas que se enfoca en el diagnóstico y tratamiento precoz de las lesiones bucales. Método: Estudio retrospectivo con historias clínicas de 1998 a 2019. Se recolectaron datos de todos los casos diagnosticados como neoplasias bucales, incluyendo diagnósticos demográficos, clínicos y microscópicos. Resultados: De los 8.952 diagnósticos histopatológicos realizados, 270 (84,64%) fueron CCE. La edad de los pacientes osciló entre 24 y 94 años (media 59,7±13,1 años), siendo más frecuente en la sexta (32,3%) y séptima (26%) décadas de la vida. Los hombres se vieron 2,5 veces más afectados que las mujeres. La mayoría de los pacientes eran de raza blanca (74,8%) y el consumo de tabaco y alcohol era frecuente. A lo largo de los años, ha habido un aumento en el número de casos diagnosticados, así como una expansión del área de cobertura del Servicio. Conclusión: El Servicio de Estomatología y Patología Bucal ha jugado un papel importante en la implementación y mejora del sistema de salud para la población local, especialmente en las Regiones del interior y áreas rurales

Comprehensive Assessment of Copy Number Alterations Uncovers Recurrent AIFM3 and DLK1 Copy Gain in Medullary Thyroid Carcinoma.

Medullary thyroid carcinoma (MTC) is a malignant tumor originating from thyroid C-cells that can occur either in sporadic (70-80%) or hereditary (20-30%) form. In this study we aimed to identify recurrent copy number alterations (CNA) that might be related to the pathogenesis or progression of MTC. We used Affymetrix SNP array 6.0 on MTC and paired-blood samples to identify CNA using PennCNV and Genotyping Console software. The algorithms identified recurrent copy number gains in chromosomes 15q, 10q, 14q and 22q in MTC, whereas 4q cumulated losses. Coding genes were identified within CNA regions. The quantitative PCR analysis performed in an independent series of MTCs (n = 51) confirmed focal recurrent copy number gains encompassing the DLK1 (14q32.2) and AIFM3 (22q11.21) genes. Immunohistochemistry confirmed AIFM3 and DLK1 expression in MTC cases, while no expression was found in normal thyroid tissues and few MTC samples were found with normal copy numbers. The functional relevance of CNA was also assessed by in silico analysis. CNA status correlated with protein expression (DLK1, p = 0.01), tumor size (DLK1, p = 0.04) and AJCC staging (AIFM3p = 0.01 and DLK1p = 0.05). These data provide a novel insight into MTC biology, and suggest a common CNA landscape, regardless of if it is sporadic or hereditary MTC.

A tetraprenylated benzophenone 7-epiclusianone induces cell cycle arrest at G1/S transition by modulating critical regulators of cell cycle in breast cancer cell lines.

Breast cancer is a complex disease and encompassing different types of tumor. Although advances in understanding of the molecular bases of breast cancer biology, the therapeutic proposals available still are not effective. In this scenario, the present study aimed to evaluate the mechanisms associated to antitumor activity of 7-Epiclusianone (7-Epi), a tetraprenylated benzophenone, on luminal A (MCF-7) and claudin-low (Hs 578T) breast cancer cell lines. We found that 7-Epi efficiently inhibited cell proliferation and migration of these cells; however MCF-7 was slightly more responsive than Hs 578T. Cell cycle analysis showed accumulation of cells at G0/G1 phase with drastic reduction of S population in treated cultures. This effect was associated to downregulation of CDKN1A (p21) and cyclin E in both cell lines. In addition, 7-Epi reduced cyclin D1 and p-ERK expression levels in MCF-7 cell line. Cytotoxic effect of 7-Epi on breast cancer cell lines was associated to its ability to increase BAX/BCL-2 ratio. In conclusion, our findings showed that 7-Epi is a promising antitumor agent against breast cancer by modulating critical regulators of the cell cycle and apoptosis.

Conservative surgical treatments for nonsyndromic odontogenic keratocysts: a systematic review and meta-analysis.

OBJECTIVES: This manuscript presents a systematic review of the clinicopathologic features and outcomes of conservative surgical treatments for nonsyndromic odontogenic keratocysts (OKCs) and assesses the recurrence rates through a meta-analysis, in order to indicate the best conservative approach. MATERIALS AND METHODS: PRISMA guidelines for systematic reviews were followed, and the protocol was registered (PROSPERO/Nr.: CRD42017060964). An electronic search was conducted using the PubMed/MEDLINE, Science Direct, Web of Science, Scopus, and The Cochrane Library databases, and relevant articles were selected based on specific inclusion criteria. The PICOS criteria (Population: nonsyndromic patients of any age with OKC, with histopathological diagnosis and minimum follow-up of 12 months; Intervention and Comparison: marsupialization or decompression with or without enucleation, and enucleation alone; Outcome: recurrence rates; Study design: clinical trials, controlled trials, retrospective studies, and case series containing at least 10 cases of OKC) were employed. A pooled odds ratio (OR) was computed through the Mantel-Haenszel test (M-H) with 95% confidence intervals (CI). RESULTS: One thousand nine hundred OKCs were analyzed; the age of the patients varied from 6 to 90 years (mean of 38.6 years); a male to female ratio of 1.57:1 was observed; 74.5% of the lesions occurred in the mandible; 75.7% of OKCs were unilocular; the association with impacted tooth was reported for 344 OKCs; and the mean follow-up was 60.1 months. One thousand three hundred thirty-one OKCs were treated by conservative surgical treatments, and 261 cases (19.8%) presented recurrence. Nonetheless, minor total recurrence rates were observed after decompression followed by enucleation (11.9%) and marsupialization followed by enucleation (17.8%). In contrast, enucleation alone showed a total recurrence rate of 20.8%. CONCLUSION: The results suggest a significant superiority of success for OKC treatments that use decompression followed by enucleation, instead of an initial enucleation (M-H, OR = 0.48; 95% CI = 0.22 to 1.08; P = 0.0163). CLINICAL RELEVANCE: No consensus exists concerning the best management for OKCs. More aggressive treatments (ostectomy, resection, or use of adjunctive therapies like Carnoy's solution and liquid nitrogen) can have many disadvantages and risks. Therefore, it is necessary to identify the conservative approach for OKCs that results in a lower recurrence rate.

M2 macrophages and inflammatory cells in oral lesions of chronic paracoccidioidomycosis.

BACKGROUND: Paracoccidioidomycosis (PCM) is a systemic fungal infection caused by Paracoccidioides brasiliensis (Pb) and associated with deficient cellular immune response, which is modulated by inflammatory cells, mainly macrophages, and cytokines. Recently, the comprehension of the macrophage polarization mediated by Th1 and Th2 cytokines has contributed to elucidate the immune response that takes part in some diseases. Thus, the aim of this study was to assess the presence of Th1- and Th2-immune response and also Pb counting in oral lesions of chronic PCM. METHODS: Forty-eight cases of chronic PCM oral lesions were included. All cases were classified as loose or dense granulomas. S100 protein, IL-1ß, IL-6, TNF-α, CD163 and CD68 immunoexpressions, and Pb localization were evaluated. The fungi present in the tissue were quantified by anti-Pb antibody. RESULTS: Most patients were white men with mean age of 47 years old and showed higher incidence of multiple lesions. Loose granulomas were predominant and exhibited a great amount of M2 macrophages, which were visualized with anti-CD163 antibody. The expression for CD163 and CD68 was similar (P = 0.05), highlighting the predominance of M2 macrophages in PCM. IL-1ß, IL-6, and TNF-α immunoexpression did not significantly change with CD163, CD68, and S100 protein. The number of fungi was significantly higher in cases with intense IL-1ß immunoexpression (P = 0.003). CONCLUSIONS: M2-activated macrophages were the majority among inflammatory cells in chronic PCM, characterizing the action of a Th2-immune response. Nevertheless, Th1 cytokines were also found; mainly IL-1ß, which was associated with fungi counting in oral lesions.

Histologic grading and nucleolar organizer regions in oral squamous cell carcinomas.

OBJECTIVE: The purposes of this study were to histologically assess different types of oral squamous cell carcinoma and the silver-binding nucleolar organizer region (AgNOR) morphology in neoplastic cells, as well as to quantify the number of AgNORs in each type of carcinoma in order to relate AgNOR count and histologic grading. MATERIAL AND METHODS: Twenty-eight cases of oral squamous cell carcinoma were divided into 4 groups, namely well-differentiated, moderately differentiated, poorly differentiated, and undifferentiated. For NOR study, 3-µm-thick sections were stained with 50% aqueous silver nitrate solution. The predominant microscopic pattern of NORs was determined. Quantitative analyses of NORs were obtained of all cells present on each histological field using a 0.025 mm² eyepiece graticule. Different histological fields were analyzed until the total number of NORs was 120 cells for each tumor. Kruskall-Wallis test was applied to compare the groups of sample data at a significance level of p=0.05. RESULTS: The mean number of AgNORs per nucleus was 3.20 for the well-differentiated group, 5.33 for the moderately differentiated one, 8.27 for the poorly differentiated one, and 10.08 for the undifferentiated one. AgNOR count was significantly different (p<0.05) among all of the studied groups. CONCLUSION: AgNOR staining technique seems to be a useful diagnostic tool since differences in AgNOR numeric values can be identified in the different types of oral squamous cell carcinoma. This technique is easy to handle and inexpensive, thus justifying its large use in histopathology.

Histologic grading and nucleolar organizer regions in oral squamous cell carcinomas

OBJECTIVE: The purposes of this study were to histologically assess different types of oral squamous cell carcinoma and the silver-binding nucleolar organizer region (AgNOR) morphology in neoplastic cells, as well as to quantify the number of AgNORs in each type of carcinoma in order to relate AgNOR count and histologic grading. MATERIAL AND METHODS: Twenty-eight cases of oral squamous cell carcinoma were divided into 4 groups, namely well-differentiated, moderately differentiated, poorly differentiated, and undifferentiated. For NOR study, 3-µm-thick sections were stained with 50 percent aqueous silver nitrate solution. The predominant microscopic pattern of NORs was determined. Quantitative analyses of NORs were obtained of all cells present on each histological field using a 0.025 mm² eyepiece graticule. Different histological fields were analyzed until the total number of NORs was 120 cells for each tumor. Kruskall-Wallis test was applied to compare the groups of sample data at a significance level of p=0.05. RESULTS: The mean number of AgNORs per nucleus was 3.20 for the well-differentiated group, 5.33 for the moderately differentiated one, 8.27 for the poorly differentiated one, and 10.08 for the undifferentiated one. AgNOR count was significantly different (p<0.05) among all of the studied groups. CONCLUSION: AgNOR staining technique seems to be a useful diagnostic tool since differences in AgNOR numeric values can be identified in the different types of oral squamous cell carcinoma. This technique is easy to handle and inexpensive, thus justifying its large use in histopathology.

Cross talk initiated by endothelial cells enhances migration and inhibits anoikis of squamous cell carcinoma cells through STAT3/Akt/ERK signaling.

It is well known that cancer cells secrete angiogenic factors to recruit and sustain tumor vascular networks. However, little is known about the effect of endothelial cell-secreted factors on the phenotype and behavior of tumor cells. The hypothesis underlying this study is that endothelial cells initiate signaling pathways that enhance tumor cell survival and migration. Here, we observed that soluble mediators from primary human dermal microvascular endothelial cells induce phosphorylation of signal transducer and activator of transcription 3 (STAT3), Akt, and extracellular signal-regulated kinase (ERK) in a panel of head and neck squamous cell carcinoma (HNSCC) cells (OSCC-3, UM-SCC-1, UM-SCC-17B, UM-SCC-74A). Gene expression analysis demonstrated that interleukin-6 (IL- 6), interleukin-8 (CXCL8), and epidermal growth factor (EGF) are upregulated in endothelial cells cocultured with HNSCC. Blockade of endothelial cell-derived IL-6, CXCL8, or EGF by gene silencing or neutralizing antibodies inhibited phosphorylation of STAT3, Akt, and ERK in tumor cells, respectively. Notably, activation of STAT3, Akt, and ERK by endothelial cells enhanced migration and inhibited anoikis of tumor cells. We have previously demonstrated that Bcl-2 is upregulated in tumor microvessels in patients with HNSCC. Here, we observed that Bcl-2 signaling induces expression of IL-6, CXCL8, and EGF, providing a mechanism for the upregulation of these cytokines in tumor-associated endothelial cells. This study expands the contribution of endothelial cells to the pathobiology of tumor cells. It unveils a new mechanism in which endothelial cells function as initiators of molecular crosstalks that enhance survival and migration of tumor cells.

Dental pulp tissue engineering with stem cells from exfoliated deciduous teeth.

Stem cells from human exfoliated deciduous teeth (SHED) have been isolated and characterized as multipotent cells. However, it is not known whether SHED can generate a dental pulp-like tissue in vivo. The purpose of this study was to evaluate morphologic characteristics of the tissue formed when SHED seeded in biodegradable scaffolds prepared within human tooth slices are transplanted into immunodeficient mice. We observed that the resulting tissue presented architecture and cellularity that closely resemble those of a physiologic dental pulp. Ultrastructural analysis with transmission electron microscopy and immunohistochemistry for dentin sialoprotein suggested that SHED differentiated into odontoblast-like cells in vivo. Notably, SHED also differentiated into endothelial-like cells, as demonstrated by B-galactosidase staining of cells lining the walls of blood-containing vessels in tissues engineered with SHED stably transduced with LacZ. This work suggests that exfoliated deciduous teeth constitute a viable source of stem cells for dental pulp tissue engineering.

Endothelial cells enhance tumor cell invasion through a crosstalk mediated by CXC chemokine signaling.

Field cancerization involves the lateral spread of premalignant or malignant disease and contributes to the recurrence of head and neck tumors. The overall hypothesis underlying this work is that endothelial cells actively participate in tumor cell invasion by secreting chemokines and creating a chemotactic gradient for tumor cells. Here we demonstrate that conditioned medium from head and neck tumor cells enhance Bcl-2 expression in neovascular endothelial cells. Oral squamous cell carcinoma-3 (OSCC3) and Kaposi's sarcoma (SLK) show enhanced invasiveness when cocultured with pools of human dermal microvascular endothelial cells stably expressing Bcl-2 (HDMEC-Bcl-2), compared to cocultures with empty vector controls (HDMEC-LXSN). Xenografted OSCC3 tumors vascularized with HDMEC-Bcl-2 presented higher local invasion than OSCC3 tumors vascularized with control HDMEC-LXSN. CXCL1 and CXCL8 were upregulated in primary endothelial cells exposed to vascular endothelial growth factor (VEGF), as well as in HDMEC-Bcl-2. Notably, blockade of CXCR2 signaling, but not CXCR1, inhibited OSCC3 and SLK invasion toward endothelial cells. These data demonstrate that CXC chemokines secreted by endothelial cells induce tumor cell invasion and suggest that the process of lateral spread of tumor cells observed in field cancerization is guided by chemotactic signals that originated from endothelial cells.

Eosinophilic ulcer of the oral mucosa versus squamous cell carcinoma.

Eosinophilic ulcer of the oral mucosa is a benign, rare, self-limiting, and generally asymptomatic lesion that shows spontaneous regression. Its etiopathogenesis is still uncertain, but trauma seems to play a fundamental role in the occurrence of this tumor. Clinically, this lesion manifests as an isolated ulcer preferentially located on the tongue, showing a raised and indurated border in addition to a white or yellowish bed. Microscopically, eosinophilic ulcer is characterized by an inflammatory infiltrate rich in leukocytes. Since these lesions show spontaneous cure, treatment becomes unnecessary, but in certain cases, cure is obtained by excision of the ulcer during biopsy. In these cases, the differential diagnosis with squamous cell carcinoma is made. A case of very small eosinophilic ulcer of the oral mucosa located on the lateral border of the tongue is presented.

Efeito da inibição dos receptores de fator de crescimento endotelial vascular na angiogênese tumoral em carcinomas espinocelulares de cabeça e pescoço / Effect of vascular endothelial growth factor receptors inhibition on tumor angiogenesis in head and neck squamous cell carcinoma

O fator de crescimento endotelial vascular (VEGF) tem sido considerado o principal indutor da angiogenese tumoral por sua ligacao a receptores especificos tirosina-quinase presentes nas celulas endoteliais (VEGFR). Uma importante via reguladora da angiogenese e caracterizada pela ligacao do VEGF ao seu receptor VEGFR-2 ativando a via de sinalizacao de PI3-K, que estimula a expressao da proteina antiapoptotica Bcl-2 elevando a expressao de citocinas pro-angiogenicas CXCL-8 e CXCL-1, o que resulta na proliferacao de celulas endoteliais. Recentemente, foi descoberta uma droga com acao antiangiogenica denominada de PTK787/ZK 222584 (PTK/ZK), que se mostrou um potente inibidor do receptor tirosina-quinase de VEGF, sem aparente efeito citotoxico em celulas que nao expressam esses receptores. Visando a melhor compreensao do mecanismo de acao e da via de atuacao antiangiogenica VEGF/VEGFR do PTK/ZK nos carcinomas espinocelulares de cabeca e pescoco, foram desenvolvidos estudos in vitro e in vivo avaliando-se a expressao de Bcl-2, CXCL-8 e CXCL-1. No presente estudo foi utilizado um modelo experimental de angiogenese humana em camundongos imunodeprimidos que receberam co-implantes de celulas tumorais e endoteliais ou apenas celulas endoteliais, tratados com administracao oral de PTK/ZK por 21 dias. A progressao tumoral nos animais foi avaliada por meio de imagem de bioluminescencia. Apos o sacrificio dos camundongos, os implantes foram incluidos em parafina sendo obtidos cortes de 3'mü'm para analise da densidade vascular e de 7'mü'm para a tecnica de microdisseccao a laser visando a avaliacao de RNA por meio de RT-PCR e PCR em tempo real nas celulas malignas e endoteliais. Concomitantemente, experimentos in vitro de co-cultura de celulas tumorais e endoteliais foram realizados para a analise de expressao de Bcl-2, CXCL-8 e CXCL-1 avaliados por meio de RT-PCR, Western Blot e teste ELISA. Os resultados demonstraram uma redução importante da expressão de Bcl-2, bem como...

Uso de invólucro plástico como barreira de proteçäo em filmes radiográficos intra-orais / Plastic cover used as a protection barrier on intra-oral radiographic films

Os autores demonstram a utilizaçäo de invólucros plásticos de polietileno em filmes radiográficos intra-orais na prevençäo à contaminaçäo dos equipamentos e instrumentos usados para o processamento dos filmes radiográficos, bem como do cirurgiäo-dentista, do pessoal auxiliar e do paciente

Cisto odontogênico calcificante / Calcifying odontogenic cyst

Trata-se de um caso clínico típico do cisto odontogênico calcificante, ocorrido em pacientes do sexo masculino, 53 anos, leucoderma, com lesão localizada na região de primeiro bicúspide inferior esquerdo, que após biópsia foi removido por enucleação. O objetivo deste trabalho é acrescentar à literatura mais um caso clínico de COC e, assim, colaborar com outros estudos, frente a esta entidade