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CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Objective: the purpose of the current study is to investigate the association between E-cadherin methylation status, hypoxia and OSCC. Methods: HaCat and SCC9 cell lines were submitted to hypoxic treatment, followed by methylation profile analysis (MS-PCR) and analysis of the expression of mRNA gene E-cadherin (RT-PCR). Study group samples comprise individuals affected by potentially malignant lesions Potential Malignant Oral Lesion (PMOL, n = 18) and oral squamous cell carcinoma (OSCC, n = 28). The control group oral mucosa (OM, n = 15) of patients with an oral mucocele. Cell migration ability was evaluated a scratch wound assay in SCC9 and HaCat cell lines. Results: E-cadherin mRNA expression in the cell lines SCC9 and HaCat was significantly reduced under hypoxia, regardless of the methylation profile, when compared to the control group. No differences in methylation profile of the E-cadherin were observed among the groups OM, PMOL and OSCC. HaCat and SCC9 presented increases in cell migration rates under hypoxia. Conclusion: the current study demonstrates that hypoxia reduces E-cadherin expression and increase cell migration, regardless of the methylation profile. Additionally, no differences in E-cadherin methylation patterns were observed among OM, PMOL and OSCC.

BACKGROUND: The histopathology and immune responses of the healing process of leishmaniasis are still poorly studied. OBJECTIVES: This study aimed to examine the histopathological and immunological aspects of lesions of patients with cutaneous leishmaniasis before and after different therapeutic methods. METHODS: We studied 23 individuals grouped according to the treatments: Glucantime, Glucantime + Leishvacin and Glucantime + Leishvacin associated with Bacillus Calmette-Guerin. For analysis of the histopathological changes present in the dermis and epidermis, histological sections were stained with hematoxylin and eosin. The samples were immunostained before and after treatment to analyze the expression of interferon (IFN)-γ, interleukin (IL) 12, IL-10 and IL-4. RESULTS: Before treatment the presence of intense infiltrates of mononuclear cells was noticed and after treatment, even with a diagnosis of clinical cure, the subjects still showed a moderate inflammatory process. In the immunohistochemical analyses, we noticed a difference between the cytokines, with increased expression of cytokines IFN-γ and IL-12 compared to IL 10 and IL-4, both before and after treatment and, comparatively, the difference in this expression was more intense before treatment. However, the cytokine expression analyzed by treatment group showed no statistically significant difference. CONCLUSION: We conclude that a clinical cure does not always coincide with the histopathological one, and that before treatment there is a predominance of Th1 cytokines. In terms of treatment type, there was no difference in the progression of healing for all the three types of treatment, indicating their clinical equivalence. FUNDAMENTOS: A histopatologia e as respostas imunológicas do processo de cura da leishmaniose são ainda pouco estudadas. OBJETIVOS: Este estudo teve como objetivo avaliar os aspectos histopatológicos e imunológicos das lesões de pacientes com leishmaniose tegumentar, antes e após diferentes métodos terapêuticos. MÉTODOS: Foram estudados 23 indivíduos agrupados de acordo com os tratamentos: Glucantime, Glucantime + Leishvacin e Glucantime + Leishvacin associado com Bacilo Calmette-Guerin. Para a análise das alterações histopatológicas presentes na derme e epiderme, cortes histológicos foram corados com hematoxilina e eosina. Para avaliar a expressão de interferon (IFN)-γ, interleucina (IL) 12, IL-10 e IL-4 foi utilizada a técnica de imuno-histoquímica antes e após o tratamento. RESULTADOS: Antes do tratamento houve um intenso infiltrado de células mononucleares, após o tratamento, mesmo com um diagnóstico de cura clínica, apresentou-se ainda um moderado processo inflamatório. Na análise imuno-histoquímica, notamos uma diferença entre as citocinas, com expressão aumentada de citocinas IFN-γ e IL-12 em comparação com IL-10 e IL-4 tanto antes quanto depois do tratamento, e comparativamente, a diferença nesta expressão mostrou-se mais intensa antes do tratamento. No entanto, a expressão das citocinas analisadas por grupo de tratamento não mostraram diferenças estatisticamente significativas. CONCLUSÃO: Concluímos que uma cura clínica nem sempre coincide com a cura histopatológica, e que antes do tratamento há uma predominância de citocinas Th1. Para os tratamentos, não houve diferença na progressão da cura para todos os três tipos de tratamento, indicando a equivalência clínica dos tratamentos.

This study aimed to evaluate the association between several different aspects of disease in head and neck squamous cell carcinoma (HNSCC): morphological grading, Ki67 proliferation index (PI), invasive front, adjacent non-malignant mucosa (ANMM), recurrence and overall survival of the patients. Sixty-four fully reviewed and followed-up patients with primary HNSCC were matched according to recurrence of the lesion and placed in one of two groups of 32 cases. Chi-square and Fisher's exact tests were used to analyze the clinicopathological parameters between both groups of patients. Association between Ki67 PI and clinicopathological parameters was also analyzed through chi-square and Fisher's exact tests with the binary logistic regression model used as a multivariate analysis. In addition, survival analysis was also performed. Our results showed that high-risk dysplasia in ANMM and high Ki67 PI in ANMM of HNSCC exhibited a higher risk of tumor recurrence. Survival analysis showed that T3/T4 tumor sizes and high Ki67 PI were significantly associated with an increase in the risk of death in multivariate analysis. Our results revealed that high-risk dysplasia and high Ki67 PI of the ANMM are parameters which are indicative of tumor recurrence. Furthermore, T3/T4 tumor sizes and high Ki67 PI in the invasive front appear to be important prognostic tools for HNSCC.

This study investigated the immunodetection of CD57+ inflammatory cells in patients with head and neck squamous cell carcinoma (HNSCC) and its association with clinicopathological parameters and overall survival. Data collected from the morphological analysis and immunohistochemical reaction testing of archived HNSCC specimens (n=70) were statistically analyzed by bivariate and multivariate statistical testing at a significance level of P0.05. The results indicate that CD57+ inflammatory cells predominate within the peritumoral stroma of HNSCC lesions and the existence of two significant relationships: between high CD57+ cell density and the development of a tumor of a large size [odds ratio (OR)=5.610, 95% confidence interval (CI)=1.516-20.763) and between high CD57+ cell density and the development of locoregional metastatic disease (OR=3.401, 95% CI=1.162-9.951). A significant difference in the rate of survival was detected only in HNSCC patients that presented large size tumors (OR=4.747, 95% CI=1.281-17.594). Together, these results suggest that although high CD57+ inflammatory cell density is associated with HNSCC lesions of greater clinical severity, the variable of cell density is not an independent predictor of HNSCC patient survival. Our findings also suggest that the relatively aggressive infiltration of CD57+ inflammatory cells in the peritumoral stroma of head and neck carcinomas may contribute to an ineffective locoregional antitumoral response.

Background The purpose of this study was to evaluate the immunohistochemical profile of cytokeratins (Ck) in pseudoepitheliomatous hyperplasia of cutaneous leishmaniasis (CL). Methods The tissue samples, with pseudoepitheliomatous hyperplasia, were collected from 37 patients (age 6–85 years old) with indolent ulcers in skin confirmed as CL. The lesions were submitted to immunolabeling for Ck pairs 4–13, 5–14, and 6–16. Results In the 37 CL cases, Ck4 and Ck13 staining were, in the majority of cases, negative. Of them, 33 and 35 cases were negative for Ck4 and Ck13, respectively. The Ck4 immunostaining was found in basal and parabasal layers, and Ck13 was viewed in the basal compartment of epithelium. Ck5 was found in 29 cases distributed homogeneously in all layers. Ck14 and Ck6 were found in all samples in all layers, and Ck16 was positive for all cases but heterogeneously found in the basal layer. Conclusion In summary, we noticed that the pattern of some Ck staining in pseudoepitheliomatous hyperplasia in CL lesions revealed intense epithelial reinforcement, protection, and proliferation.

Introduction Chronic dental periapical lesions result from chronic inflammation of periapical tissues caused by continuous antigenic stimulation from infected root canals. Recent findings have suggested that T helper (Th) 1 and Th2-like cytokines are important in the pathogenesis of chronic periapical inflammatory diseases. However, the mechanisms regulating these immunoinflammatory pathways have not been fully elucidated. Thus, the aim of this study was to evaluate interleukin (IL)-4, IL-12, and interferon γ (IFN-γ) protein levels in human radicular cysts and periapical granulomas. Methods Archived samples of cysts (n = 52) and granulomas (n = 27) were sectioned and submitted to immunohistochemistry to evaluate the tissue expression of IL-4, IL-12, and IFN-γ. The data were analyzed using the Mann-Whitney U test (P Results An increased expression of IFN-γ was observed in radicular cysts. IL-4 expression was stronger in periapical granulomas than in radicular cysts. IL-12 was not detected in any of the samples. Conclusions Our study showed that IFN-γ protein levels are increased in radicular cysts, whereas IL-4 expression is stronger in samples of periapical granulomas. Further studies are necessary to elucidate the signaling pathways mediated by these cytokines and to facilitate the development of more effective periapical disease management strategies.

The purpose of this study was to assess the LEPR gene Gln223Arg polymorphism (rs1137101) in oral squamous cell carcinoma (OSCC) and in potentially malignant oral lesions (PMOL) in comparison to normal oral mucosa in a Brazilian population. Smokers (n = 89) were selected from a representative sample of 471 individuals from the general population of Montes Claros, Brazil. Participants were age and gender matched to patients with OSCC (n = 25) and oral epithelial dysplasia (n = 25). We investigated the LEPR Gln223Arg polymorphism (A>G; rs1137101) in these groups. Genotype variants were assessed by RFLP-PCR, using MspI (HPAII) restriction endonuclease. The institutional review board of the Universidade Estadual de Montes Claros approved the study (process number 2667/2011). Written informed consent for this study was obtained from all participants. The GG genotype (Arg223Arg) appears to be the more relevant polymorphic variant in OSCC. It occurred, approximately, twice as frequently in OSCC patients than in the general population. In contrast, the A allele in its homozygosis form (Gln223Gln) is significantly associated with the development of PMOL; 80% of the samples from the PMOL group exhibit AA genotype. Our findings suggest new insights regarding LEPR gene variations in the development of OSCC and PMOL.

Calcifying cystic odontogenic tumors (CCOTs) are benign cystic lesions of odontogenic origin characterized by an ameloblastoma-like epithelium and the presence of a group of cells named ghost cells. The pattern of cytokeratin (Ck) expression on these lesions remains unclear and needs to be clarified. To this end, the expression of Ck6, Ck13, Ck14, Ck18, and Ck19 in the epithelium lining of 7 cases of CCOTs was evaluated by immunohistochemistry. For this, the epithelium lining was divided into 3 distinct regions: basal layer, suprabasal layer, and the compartment composed of ghost cells. In this study, 6 cases (85.7%) were classified as type 1 and 1 (14.3%) as type 4. All cases were negative for Ck13 and Ck18, despite the epithelial layer, as well as in the ghost cells. Ck6 was only positive in the ghost cells. Positivity for Ck14 and Ck19 was found in the basal and suprabasal layers, including the ghost cells. The results showing positivity for Ck14 and Ck19 in all of the analyzed cases reinforce CCOT as being of odontogenic origin, and the restricted expression of Ck6 in the ghost cells may be indicative that these cells suffer an altered differentiation into hair follicles in CCOTs.

The present study aimed to compare levels of VEGFR2 and MMP-9 among control, epithelial dysplasia (ED) and oral squamous cell carcinoma (OSCC) groups. We analyzed 48 patients with oral leukoplakia (OL), 20 patients with OSCC and 21 patients without OL and OSCC. Immunohistochemistry of VEGFR2 and MMP9 were performed and compared among groups. Analysis of tissue immunolocalization of VEGFR2 and MMP-9 assumed non-parametrical distribution and comparison between groups was performed using the Mann-Whitney and Kruskal-Wallis statistical tests. VEGFR2 and MMP9 immunoexpression appeared to correlate with the degree of dysplasia and was observed to increase in lesions with more severe dysplasia as compared to those with lower degrees of dysplasia. Immunoreactivity of MMP-9 was lower in the OL samples compared to the OSCC samples (p = 0.004). We observed no difference in VEGFR2 protein levels between OL and OSCC samples. A positive correlation was found between VEGFR2 and MMP-9 in OL samples (r = +0.452, p = 0.001), however, no correlation was found in OSCC samples (r = -0.042, p = 0.861). In conclusion, the results of the current study suggest that expression of MMP9 and VEGFR2 is associated with ED grading and MMP9 levels are increased in OSCC.

BACKGROUND: Leishmaniases are zoonoses considered a public health problem, representing a complex group of diseases with a broad clinical spectrum and epidemiological diversity. Leishmaniasis is caused by several species of protozoa of the genus Leishmania. The evolution of the pathology and the resolution of the leishmaniasis are dependent mainly on the Leishmania species involved, although the cytokine profile plays an important role in the development of the immune response. OBJECTIVES: The purpose of our study was to evaluate the immune response of patients affected by lesions of cutaneous leishmaniasis by immunostaining of the OX40, CD20, IFN-γ and IL-4 proteins. METHODS: The tissue samples were collected from indolent skin ulcers confirmed as cutaneous leishmaniasis of 41 patients aged between six and 90 years. The lesions were submitted to OX40, CD20, INF-γ and IL-4 immunolabeling. RESULTS: We observed a statistically significant higher expression of IFN-γ compared with IL-4 (p=0.009). Besides, OX40 had higher expression when compared with CD20 (p

BACKGROUND: Leishmaniasis is caused by protozoa of Leishmania spp. genus. It is transmitted by the bite of the sand fly insect. It is believed that 12 million people are infected with this disease and that its annual incidence is 2 million; this number is increasing. OBJECTIVES: The present study aimed to evaluate the expression of myofibroblasts through alpha smooth muscle actin labeling, and to analyze their relationship with the expression of the cytokines Interferon gama (IFN-γ) and Transforming growth factor beta (TGF-β1) in lesions of American tegumentary leishmaniasis (ATL). METHODS: For this retrospective study, we gathered 28 patients diagnosed with ATL between 2002 and 2006. We verified α-SMA positivity and performed IFN-γ and TGF-β1 immunolabeling to identify the profile of these cytokines in both positive and negative cases for myofibroblasts, via immunohistochemistry, in order to assess the presence of myofibroblasts,. RESULTS: We observed that out of the 28 cases, 17 (60.71%) were positive for alpha smooth muscle actin, while 11 (39.29%) were negative, and IFN-γ was more expressed than TGF-β1 (p=0.007). The mean percentages of expression of IFN-γ and TGF-β1 in the group negative for alpha smooth muscle actin were different, with an increased expression of IFN-γ (p=0.047). However, in the group positive for alpha smooth muscle actin, there was no difference in cytokine labeling (p>0.05). CONCLUSION: We verified the presence of positive α-SMA stromal cells in the majority of the cases of ATL, indicating the presence of myofibroblasts. In cases negative for alpha smooth muscle actin, an increased expression of IFN-γ compared to TGF-β1 was observed, revealing an inflammatory phase progressing to a healing process. FUNDAMENTOS: A leishmaniose é causada pelo protozoário do gênero Leishmania spp., sendo transmitida via picada do inseto flebotomíneo. Estima-se que 12 milhões de indivíduos estejam infectados com a doença, sendo a incidência anual de 2 milhões, número este que tende a aumentar. OBJETIVOS: Avaliar a expressão de miofibroblastos através da imunomarcação de actina de músculo liso alfa, e analisar sua relação com a expressão de citocinas IFN-γ e TGF-β1 nas lesões de pacientes com leishmaniose tegumentar americana. MÉTODOS: Trata-se de um estudo retrospectivo, em que foram avaliados 28 pacientes diagnosticados com leishmaniose tegumentar americana durante o período de 2002 a 2006. Na técnica de imuno-histoquímica avaliou-se a presença de miofibroblastos, através do marcador actina de músculo liso alfa, além da imunomarcação do IFN-γ e TGF-β1 para identificar o perfil dessas citocinas nos casos positivos e negativos para miofibroblastos. RESULTADOS: Observou-se que dos 28 casos, 17 (60,71%) foram positivos para actina de músculo liso alfa, enquanto 11 (39,29%) foram negativos. IFN-γ teve uma maior expressão do que TGF-β1 (p=0,007). A porcentagem média de expressão de IFN-γ e TGF-β1 no grupo negativo para actina de músculo liso alfa foi diferente, apresentando uma maior expressão de IFN-γ (p=0.047). Entretanto, o grupo positivo para actina de músculo liso alfa não apresentou uma diferença estatisticamente significativa (p>0,05). CONCLUSÃO: Verificou-se uma expressão de actina de músculo liso alfa nos casos de leishmaniose tegumentar americana, indicando a presença de miofibroblastos. Nos casos negativos para actina de músculo liso alfa, observou-se uma maior expressão de IFN-γ comparando com TGF-β1, revelando que a fase inflamatória está envolvida no processo de cicatrização da lesão.