Microvascular density of regenerative nodule to small hepatocellular carcinoma by automated analysis using CD105 and CD34 immunoexpression.

BACKGROUND: Angiogenesis is a proliferative process resulting in the development of new blood vessels from existing endothelial cells and is considered crucial for tumor growth and metastasis. Tumor angiogenesis can be quantified by microvascular density (MVD), which is evaluated in highly vascularized tumor areas (hot spots) by immunohistochemical assays using CD34 and CD31 pan-endothelial antibodies. More recently, CD105 has been successfully used for some tumor types because it could discriminate neovascularization. The expression of CD34 and CD105 in hepatocellular carcinomas (HCC) and hepatic precancerous lesions has been reported-although the results for CD105 are controversial-but to the best our knowledge, CD105 has not been previously investigated in dysplastic nodules (DN). We investigated and compared MVD-CD34 and MVD-CD105 immunoexpression in tissues containing different stages of hepatocarcinogenesis, including DN. METHODS: A total of 31 regenerative nodules (RN), 26 DN and 25 small HCC from explants were used for immunohistochemical tests with CD34 and CD105 antibodies. Antibody expression was quantified by computerized image analysis measurement of MVD, areas containing highly positive endothelial cells within the nodules. RESULTS: The median MVD for CD34 was higher in HCC than in DN and RN (p < 0.01), and was higher in DN compared with RN (p = 0.033). In contrast, MVD with CD105 was higher in RN, and the difference was significant in RN and DN compared with HCC (p = 0.019 and p = 0.012, respectively). When MVD with CD34 and CD105 were compared within a single group, there was a significant predominance of CD105 in RN and DN (p < 0.01). In addition, MVD-C34 in HCC predominated compared with MVD-CD105, but the difference was not statistically significant (p = 0.128). CONCLUSIONS: This study identified a close relationship between CD105 and liver cirrhosis, and that CD34 antibody is a good endothelial marker for hepatic carcinogenesis. There was no difference between the use of CD105 and CD34 antibodies in preneoplastic lesions.

Gene expression analysis by real-time PCR: experimental demonstration of PCR detection limits.

Reverse transcription followed by real-time PCR (RT-qPCR) is the gold standard for quantifying gene expression. However, because of PCR detection limits, theorized to be three template copies, the quantification of genes exhibiting great expression variability is challenging. Using genes with high to low expression in rat tissues we experimentally demonstrated this limit and found it to be applicable only for describing reactions in which stochastic events and the Monte Carlo effect are present. We also determined the lower limits of RNA input that should be used to prevent artifactual template quantification and we propose a methodology to assess RT-qPCR detection limits in any qPCR platform.

The significance of p53 immunoexpression with different clones (DO-7 and PAb-240) in oral squamous cell carcinoma.

BACKGROUND/AIM: The TP53 gene is a tumor suppressor gene. Its product is a nuclear protein that regulates cell cycle arrest, apoptosis and DNA repair. Anti-p53 clones DO-7 and PAb-240 recognize the amino acid sequences 21-25 and 213-217, respectively. This study aimed to evaluate the expression of these clones and their relationship with clinicopathological features and survival analysis in oral squamous cell carcinomas (OSCC). METHODS: Information on 53 primary OSCC was collected at the Brazilian National Cancer Institute. An immunohistochemical method was applied to evaluate p53 expression (DO-7 and PAb-240). Their expression was analyzed quantitatively and correlated with clinicopathological features. Kaplan-Meier survival curves and log rank test were used. RESULTS: Immunopositivity for DO-7 was present in 64% of the cases, while 58% were positive for PAb-240. There was no correlation between immunoexpression of both antibodies and clinicopathological features or survival analysis. DO-7 expression was significantly higher (p = 0.001) than that of PAb-240. CONCLUSIONS: There were quantitative differences between the expression of the antibodies studied, which may reflect a different specificity of each one. To confirm immunohistochemical results and estimate the true prognostic role of TP53 in OSCC, it is important to perform mutation analysis.

Quantitative evaluation of SPRR3 expression in esophageal squamous cell carcinoma by qPCR and its potential use as a biomarker.

Esophageal squamous cell carcinoma (ESCC) is highly fatal due to late diagnosis and inefficient treatment. Early disease detection could improve diagnosis and patient survival. Esophageal squamous epithelial cells express SPRR3, a member of the small proline-rich protein family, which is downregulated in ESCC. Therefore, SPRR3 expression may be used as a biomarker to follow the transition from healthy mucosa to ESCC. Both SPRR3 mRNA splice variants, v1 and v2, were evaluated by real time PCR in tumor and histologically normal adjacent tissue biopsies from 84 ESCC patients and 18 healthy controls. SPRR3-v1 was most highly expressed in the esophageal mucosa of healthy subjects, with an increasingly lower expression in the adjacent mucosa of ESCC patients and in tumors, respectively. SPRR3-v2 expression was low in normal mucosa and in tumors but it was higher in the adjacent mucosa of ESCC patients. In addition, we found a significant correlation between a lower SPRR3-v1 and SPRR3-v2 expression and age and alcohol consumption, respectively. SPRR3 protein expression presented a good correlation with SPRR3 mRNA expression. Cut-off points to discriminate between healthy mucosa, tumor and adjacent mucosa were determined with receiver operating characteristic (ROC) curves. This analysis showed that SPRR3-v1 expression discriminates the esophageal mucosa of healthy subjects from the adjacent mucosa and the tumor of ESCC patients with high sensitivity and specificity. Our data shows that the quantitative analysis of SPRR3 mRNA is a robust and reliable method to monitor the malignant transformation of the healthy esophageal mucosa into ESCC.

How pathological criteria can impact prognosis of tongue and floor of the mouth squamous cell carcinoma.

other: Pathological parameters have been indicated as tumor prognostic factors in oral carcinoma. OBJECTIVE: The objective of this study was to investigate the impact of pathological parameters on prognosis of patients affected only by tongue and/or floor of the mouth squamous cell carcinoma (SCC). METHODOLOGY: In total, 380 patients treated in the Brazilian National Cancer Institute (INCA) from 1999 to 2006 were included. These patients underwent radical resection followed by neck dissection. The clinical and pathological characteristics were recorded. The Kaplan-Meier method and Cox proportional hazards model were used in survival analysis. Overall survival (OS), cancer-specific survival (CSS) and disease-free interval (DFI) were estimated. Cox residuals were evaluated using the R software version 3.5.2. Worst OS, CSS and DFI were observed in patients with tumors in advanced pathological stages (p<0.001), with the presence of perineural invasion (p<0.001) and vascular invasion (p=0.005). RESULTS: Advanced pathological stage and the presence of a poorly differentiated tumor were independent prognostic factors for OS and CSS. However, advanced pathological stage and perineural invasion were independent predictors of a shorter OS, DFI and CSS. CONCLUSION: Pathological stage and perineural invasion were the most significant pathological variables in survival analysis in tongue and/or floor of the mouth SCC.

Reproducibility of immunostaining quantification and description of a new digital image processing procedure for quantitative evaluation of immunohistochemistry in pathology.

Quantification of immunostaining is a widely used technique in pathology. Nonetheless, techniques that rely on human vision are prone to inter- and intraobserver variability, and they are tedious and time consuming. Digital image analysis (DIA), now available in a variety of platforms, improves quantification performance: however, the stability of these different DIA systems is largely unknown. Here, we describe a method to measure the reproducibility of DIA systems. In addition, we describe a new image-processing strategy for quantitative evaluation of immunostained tissue sections using DAB/hematoxylin-stained slides. This approach is based on image subtraction, using a blue low pass filter in the optical train, followed by digital contrast and brightness enhancement. Results showed that our DIA system yields stable counts, and that this method can be used to evaluate the performance of DIA systems. The new image-processing approach creates an image that aids both human visual observation and DIA systems in assessing immunostained slides, delivers a quantitative performance similar to that of bright field imaging, gives thresholds with smaller ranges, and allows the segmentation of strongly immunostained areas, all resulting in a higher probability of representing specific staining. We believe that our approach offers important advantages to immunostaining quantification in pathology.

Association of bruxism and anxiety symptoms among military firefighters with frequent episodic tension type headache and temporomandibular disorders.

OBJECTIVE: To assess the presence of bruxism and anxiety among military firefighters with frequent episodic tension-type headache and painful temporomandibular disorders (TMDs). METHODS: The sample consisted of 162 individuals aged 18 to 55 years divided into four groups. Headache was diagnosed in accordance with the International Classification of Headache Disorders-III. The Research Diagnostic Criteria for Temporomandibular Disorders questionnaire was used to classify TMDs and awake bruxism; sleep bruxism was diagnosed in accordance with the International Classification of Sleep Disorders-3; and anxiety was classified using the Beck Anxiety Inventory. In statistical models, a significance level of 95% was used. The chi-square test was used to assess anxiety. RESULTS: Associations were found among frequent episodic tension-type headache, painful TMDs, awake bruxism and anxiety (p < 0.0005). Sleep bruxism was not a risk factor (p = 0.119) except when associated with awake bruxism (p = 0.011). CONCLUSION: Anxiety and awake bruxism were independent risk factors for developing frequent episodic tension-type headache associated with painful TMDs; only awake bruxism was a risk factor for frequent episodic tension-type headache with non-painful TMDs.

Achromobacter xylosoxidans infection in cystic fibrosis siblings with different outcomes: Case reports.

INTRODUCTION: The clinical relevance of Achromobacter xylosoxidans infection in cystic fibrosis (CF) remains controversial. This emerging agent in CF has been associated with increased lung inflammation, more frequent exacerbations and more severe lung disease. We describe a pair of CF siblings chronically colonized by the same multilocus genotype of A. xylosoxidans with different clinical courses, and assess whether this species may have developed any virulence traits and antimicrobial resistance that could have contributed to their singular outcomes. CASE PRESENTATION: Two siblings were positive for the F508del and Y1092X mutations, and were chronically colonized by Pseudomonas aeruginosa and Staphylococcus aureus. The female patient had a more severe CF phenotype and faster clinical deterioration than her brother. Her pulmonary function and computed tomography scan lesions were worse than those of her brother, and both parameters progressively declined. She died at 14 years of age, when he was 18. All isolates of A. xylosoxidans were biofilm producers. Achromobacter xylosoxidans showed less swarming motility in the female patient. CONCLUSIONS: Biofilm production and diminution of motility allow persistence. Only swarming motility differed between the isolates recovered from the two siblings, but this finding is not sufficient to explain the different clinical outcomes despite their similar genotypes. Modifier genes, unknown environmental factors and female gender can partially explain differences between these siblings. We were unable to correlate any microbiological findings with their clinical courses, and more translational studies are necessary to decrease the gap of knowledge between laboratory and clinical data to promote better clinical interventions.

Immunoexpression of cleaved caspase-3 shows lower apoptotic area indices in lip carcinomas than in intraoral cancer.

OBJECTIVE: This study aimed to evaluate apoptosis by assessing cleaved caspase-3 immunoexpression in hyperplastic, potentially malignant disorder (PMD), and malignant tumors in intraoral and lower lip sites. MATERIAL AND METHODS: A retrospective study using paraffin blocks with tissues from patients with inflammatory fibrous hyperplasia (IFH), actinic cheilitis, oral leukoplakia, lower lip and intraoral squamous cell carcinoma (SCC) was performed. The tissues were evaluated by immunohistochemical analysis with anti-cleaved caspase-3 antibody. Apoptotic area index was then correlated with lesion type. RESULTS: From 120 lesions assessed, 55 (46%) were cleaved caspase-3-positive. The SCC samples (n=40) had the highest apoptotic area indices (n=35; 87.5%). Significant differences were detected between SCCs and PMDs (p=0.0003), as well as SCCs and IFHs (p=0.001), regarding caspase-3 immunopositivity. Carcinomas of the lower lip had lower apoptotic area indices than intraoral cancer (p=0.0015). CONCLUSIONS: Cleaved caspase-3 immunoexpression showed differences in oral SCCs and PMDs and demonstrated a distinct role of apoptosis in carcinogenesis of intraoral and lower lip cancer. In future, the expression of cleaved caspase-3 with other target molecules in oral cancer may be helpful in delineating the prognosis and treatment of these tumors.

How pathological criteria can impact prognosis of tongue and floor of the mouth squamous cell carcinoma

Abstract Pathological parameters have been indicated as tumor prognostic factors in oral carcinoma. Objective: The objective of this study was to investigate the impact of pathological parameters on prognosis of patients affected only by tongue and/or floor of the mouth squamous cell carcinoma (SCC). Methodology: In total, 380 patients treated in the Brazilian National Cancer Institute (INCA) from 1999 to 2006 were included. These patients underwent radical resection followed by neck dissection. The clinical and pathological characteristics were recorded. The Kaplan-Meier method and Cox proportional hazards model were used in survival analysis. Overall survival (OS), cancer-specific survival (CSS) and disease-free interval (DFI) were estimated. Cox residuals were evaluated using the R software version 3.5.2. Worst OS, CSS and DFI were observed in patients with tumors in advanced pathological stages (p<0.001), with the presence of perineural invasion (p<0.001) and vascular invasion (p=0.005). Results: Advanced pathological stage and the presence of a poorly differentiated tumor were independent prognostic factors for OS and CSS. However, advanced pathological stage and perineural invasion were independent predictors of a shorter OS, DFI and CSS. Conclusion: Pathological stage and perineural invasion were the most significant pathological variables in survival analysis in tongue and/or floor of the mouth SCC.

Association of bruxism and anxiety symptoms among military firefighters with frequent episodic tension type headache and temporomandibular disorders / Associação de bruxismo e sintomas de ansiedade em bombeiros militares com cefaleia do tipo tensional episódica frequente e desordens temporomandibulares

ABSTRACT Objective To assess the presence of bruxism and anxiety among military firefighters with frequent episodic tension-type headache and painful temporomandibular disorders (TMDs). Methods The sample consisted of 162 individuals aged 18 to 55 years divided into four groups. Headache was diagnosed in accordance with the International Classification of Headache Disorders-III. The Research Diagnostic Criteria for Temporomandibular Disorders questionnaire was used to classify TMDs and awake bruxism; sleep bruxism was diagnosed in accordance with the International Classification of Sleep Disorders-3; and anxiety was classified using the Beck Anxiety Inventory. In statistical models, a significance level of 95% was used. The chi-square test was used to assess anxiety. Results Associations were found among frequent episodic tension-type headache, painful TMDs, awake bruxism and anxiety (p < 0.0005). Sleep bruxism was not a risk factor (p = 0.119) except when associated with awake bruxism (p = 0.011). Conclusion Anxiety and awake bruxism were independent risk factors for developing frequent episodic tension-type headache associated with painful TMDs; only awake bruxism was a risk factor for frequent episodic tension-type headache with non-painful TMDs.

RESUMO Objetivo Avaliar a presença de bruxismo e sintomas de ansiedade entre bombeiros militares com cefaleia do tipo tensional episódica frequente (CTTEF) e desordens temporomandibulares Dolorosas (DTMs). Métodos A amostra foi composta por 162 indivíduos com idade entre 18 e 55 anos divididos em quatro grupos. A CTTEF foi diagnosticada de acordo com o ICHD-III. O RDC / TMD foi usado para classificar as DTMs e o bruxismo acordado; o bruxismo do sono foi diagnosticado de acordo com o ICSD-3; e a ansiedade foi classificada usando o Inventário de Ansiedade de Beck. Nos modelos estatísticos, utilizou-se um nível de significância de 95%. O teste Qui-quadrado avaliou a ansiedade. Resultados Associações foram encontradas entre CTTEF, DTMs dolorosas, bruxismo diurno e ansiedade (p < 0,0005). O bruxismo do sono não foi fator de risco (p = 0,119), mas quando associado à atividade diurna (p = 0,011). Conclusão Ansiedade e bruxismo diurno foram fatores de risco independentes para o desenvolvimento de CTTEF associado a DTMs dolorosas. Apenas o bruxismo diurno foi fator de risco para CTTEF com DTMs não dolorosas.

Multidrug resistant Mycobacterium tuberculosis: a retrospective katG and rpoB mutation profile analysis in isolates from a reference center in Brazil.

BACKGROUND: Multidrug resistance is a critical factor in tuberculosis control. To gain better understanding of multidrug resistant tuberculosis in Brazil, a retrospective study was performed to compare genotypic diversity and drug resistance associated mutations in Mycobacterium tuberculosis isolates from a national reference center. METHODS AND FINDINGS: Ninety-nine multidrug resistant isolates from 12 Brazilian states were studied. Drug-resistance patterns were determined and the rpoB and katG genes were screened for mutations. Genotypic diversity was investigated by IS6110-RFLP and Luminex 47 spoligotyping. Mutations in rpoB and katG were seen in 91% and 93% of the isolates, respectively. Codon 315 katG mutations occurred in 82.8% of the isolates with a predominance of the Ser315Thr substitution. Twenty-five isolates were clustered in 11 groups with identical IS6110-RFLP patterns while 74 showed unique patterns with no association between mutation frequencies or susceptibility profiles. The most prevalent spoligotyping lineages were LAM (47%), T (17%) and Haarlen (12%). The Haarlen lineage showed a higher frequency of codon 516 rpoB mutations while codon 531 mutations prevailed in the other isolates. CONCLUSIONS: Our data suggest that there were no major multidrug resistant M. tuberculosis strains transmitted among patients referred to the reference center, indicating an independent acquisition of resistance. In addition, drug resistance associated mutation profiles were well established among the main spoligotyping lineages found in these Brazilian multidrug resistant isolates, providing useful data for patient management and treatment.

Lower lip squamous cell carcinoma in patients with photosensitive disorders: Analysis of cases treated at the Brazilian National Cancer Institute (INCA) from 1999 to 2012

Background: Lower lip squamous cell carcinoma (LLSCC) is a common malignancy of the head and neck, being mainly a consequence of a chronic exposure to ultraviolet (UV) light solar radiation. Here, we evaluated the clinicopathological profile of patients with photosensitive disorders (xeroderma pigmentosum, lupus erythematosus and albinism) that developed LLSCC. Material and Methods: Data from patients who had a diagnosed LLSCC with a prior xeroderma pigmentosum, lupus erythematosus or albinism diagnosis that were treated at INCA from 1999 to 2012 were collected from patients' medical records (n=16). The control group was composed of 68 patients with LLSCC without a medical history of photosensitivity. The clinicopathological data of this study population were collected and the association between these variables was analyzed by Fisher's exact test. Survival curves were constructed using the Kaplan-Meier method and compared by log-rank test. All statistical analyses were performed using SPSS statistics package. Results: The mean age of patients in the photosensitive and non-photosensitive groups was 42 years and 67 years, respectively (p<0.0001). A previous history of malignant diseases was more common in the photosensitive group (p=0.001). In both groups, most tumors showed a pathological stage I/II disease. Overall and cancer-specific survival were not statistically different. However, disease-free interval showed a significant difference (p=0.01) between the photosensitive and non-photosensitive patients. Conclusions: Photosensitive patients presented LLSCC at earlier age but it usually was not the primary tumor in these patients. Furthermore, a more aggressive pathological behavior was not seen when compared with tumors from non-photosensitive patients. The disease-free interval was lower in photosensitive patients, as expected (AU)

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Immunoexpression of cleaved caspase-3 shows lower apoptotic area indices in lip carcinomas than in intraoral cancer

ABSTRACT Objective This study aimed to evaluate apoptosis by assessing cleaved caspase-3 immunoexpression in hyperplastic, potentially malignant disorder (PMD), and malignant tumors in intraoral and lower lip sites. Material and Methods A retrospective study using paraffin blocks with tissues from patients with inflammatory fibrous hyperplasia (IFH), actinic cheilitis, oral leukoplakia, lower lip and intraoral squamous cell carcinoma (SCC) was performed. The tissues were evaluated by immunohistochemical analysis with anti-cleaved caspase-3 antibody. Apoptotic area index was then correlated with lesion type. Results From 120 lesions assessed, 55 (46%) were cleaved caspase-3-positive. The SCC samples (n=40) had the highest apoptotic area indices (n=35; 87.5%). Significant differences were detected between SCCs and PMDs (p=0.0003), as well as SCCs and IFHs (p=0.001), regarding caspase-3 immunopositivity. Carcinomas of the lower lip had lower apoptotic area indices than intraoral cancer (p=0.0015). Conclusions Cleaved caspase-3 immunoexpression showed differences in oral SCCs and PMDs and demonstrated a distinct role of apoptosis in carcinogenesis of intraoral and lower lip cancer. In future, the expression of cleaved caspase-3 with other target molecules in oral cancer may be helpful in delineating the prognosis and treatment of these tumors.

Expression of Bcl-2 family proteins and associated clinicopathologic factors predict survival outcome in patients with oral squamous cell carcinoma.

The aims of this study were to assess the expression levels of three proteins involved in apoptosis--Bcl-2, Bcl-X, and Bax--and evaluate their relationship with clinicopathologic features and survival in oral squamous cell carcinoma (OSCC). Immunohistochemistry was used to evaluate protein expression in 53 primary OSCCs treated by radical surgery with free margins at a single institution in 1999. Histologic specimens were graded and analyzed for perineural invasion, lymphocytic infiltrate, and pattern of invasion. Digital image analysis was performed to quantify immunostaining. Survival was analyzed using the Kaplan-Meier method and Cox's proportional hazard model. Cancer-specific 5-year survival (CSS) was 61% (56% overall survival (OS), and 51% disease-free interval (DFI)). Kaplan-Meier analysis identified pathologic stage (p=0.0007, log-rank test, OS), negative nodes status (pN) (p<0.0001, log-rank test, OS), presence of lymphocytic infiltrate (p=0.0084, log-rank test, OS), and high Bax expression (p=0.025, log-rank test, OS) to each be associated with both better OS and CSS. Tongue tumors (p=0.0179, log-rank test), worst pattern of invasion (p=0.0293, log-rank test), lack of lymphocytic infiltrate (p=0.0328, log-rank test), perineural invasion (p=0.0448, log-rank test), poorly differentiated tumors (p=0.0318, log-rank test), and low Bcl-X expression (p=0.044, log-rank test) were all associated with a low DFI. Cox regression found pN, lymphocytic infiltrate, and Bax expression to be independent prognostic factors for OS and CSS, whereas lymphocytic response and tongue tumors were predictors of DFI. Bcl-2 expression emerged as an independent marker of favorable CSS. Lymphocytic infiltrate was the most meaningful histopathologic parameter in survival analysis, whereas expression of Bcl-2 family members seems to be an important marker of a favorable prognosis in OSCC.

Análise comparativa da imunoexpressão da proteína p53 (clones DO-7 e PAb-240) em carcinomas de células escamosas intrabucais e labiais / Comparative analysis of p53 protein immunostaining (antibodies DO-7 and PAb-240) in oral cavity and lip squamous cell carcinomas

INTRODUÇÃO: A carcinogênese caracteriza-se como um processo multifatorial, e a inativação da proteína p53 é uma alteração genética comumente observada nos carcinomas de células escamosas de boca (CCEB). OBJETIVO: Analisar e comparar a imunoexpressão da proteína p53, por meio dos clones DO-7 e PAb-240, em CCEB com localização intrabucal e em lábio inferior. MATERIAL E MÉTODOS: Foram selecionados 40 casos de CCEB, sendo 20 de localização intrabucal e 20 em lábio inferior. Foi realizado um estudo imuno-histoquímico utilizando os anticorpos anti-p53 clone DO-7 e PAb-240. A imunoquantificação foi realizada por meio de análise digital de imagem, e os resultados, submetidos a tratamentos estatísticos. RESULTADOS: A imunoexpressão da proteína p53 foi verificada com o anticorpo DO-7 em 13 casos (65 por cento) de carcinoma intrabucal e em 19 (95 por cento) de carcinoma de lábio inferior. Imunorreatividade para o anticorpo PAb-240 foi observada em 9 casos (45 por cento) de lesões intrabucais e em 15 (75 por cento) localizados em lábio inferior. Não foram observadas, segundo o teste de Mann-Whitney, diferenças estatisticamente significativas (p > 0,05) na expressão da proteína p53 entre as duas localizações estudadas, independentemente do anticorpo avaliado. Foram identificadas, pelo teste de Wilcoxon, diferenças estatisticamente significativas entre a expressão dos clones DO-7 e PAb-240 em cada um dos grupos analisados (valor p = 0,013 - lábio inferior; valor p = 0,016 - intrabucal). CONCLUSÕES: A expressão da proteína p53 observada nos CCEB, com localizações intrabucais e labiais, sugere a ocorrência de mutações no gene TP53. As diferenças quantitativas obtidas entre os anticorpos estudados, independentemente da localização das lesões, refletem uma especificidade distinta entre os clones DO-7 e PAb-240. O desenvolvimento de mais estudos será fundamental para estabelecer o anticorpo mais adequado para proteína p53 em CCEB.

BACKGROUND: Carcinogenesis is a multifactorial process and inactivation of p53 protein is a genetic change commonly observed in oral squamous cell carcinomas (OSCC). OBJECTIVES: To analyze and compare the expression of p53 protein through antibodies DO-7 and PAb-240 in OSCC samples located in the oral cavity and lower lip. MATERIAL AND METHODS: Forty cases of OSCC were selected and divided into oral cavity and lower lip groups (20 cases each). Immunohistochemical technique was performed using antibodies DO-7 and PAb-240. Quantification of the cases was performed through digital image analysis and underwent specific statistical treatments. RESULTS: Expression of p53 protein was verified with DO-7 antibody in 13 cases (65 percent) of oral cavity carcinomas and in 19 cases (95 percent) of lower lip carcinoma. PAb-240 positivity was detected in 9 cases (45 percent) of oral cavity lesions and in 15 cases (75 percent) located in the lower lip. According to Mann-Whitney test, there were no statistically significant differences between the expressions of p53 protein in both groups, regardless of the antibody used. According to Wilcoxon test, there were statistically significant differences between the expression of DO-7 antibody and PAb-240 in each of the analyzed groups (p-value = 0.013; lower lip p-value = 0.016 - oral cavity). CONCLUSIONS: The expression of p53 protein was observed both in the oral cavity and lip OSCC, which suggests the occurrence of mutations in TP53 gene. The quantitative differences between the antibodies studied, regardless of the site of the lesions, reflect different specificity between clones DO-7 and PAb-240. Further studies are required to establish the best antibody for p53 protein in oral squamous cell carcinomas.

Classificações histopatológicas para o carcinoma de células escamosas da cavidade oral: revisão de sistemas propostos / Histological classifications of oral squamous cell carcinoma: a review of the proposed systems

O sistema de estadiamento clínico de tumores TNM tem sido a classificação adotada para caracterizar os tumores, propor a terapia mais adequada e estimar a sobrevida dos pacientes. As informações obtidas através dos exames clínico e de imagem são utilizadas para estabelecer o estádio clínico (cTNM) e, caso o paciente seja submetido à cirurgia, determina-se o estádio patológico (pTNM) mediante o exame histopatológico do tumor e dos linfonodos regionais. Entretanto tumores clinicamente precoces, mesmo tratados adequadamente, podem causar a morte do paciente. Assim, classificações histopatológicas para os carcinomas de células escamosas (CCE) de cavidade oral surgiram na tentativa de explicar o comportamento biológico discrepante dos tumores. Broders, em 1920, propôs uma gradação histopatológica baseada no grau de diferenciação celular. Contudo muitos autores questionam o valor dessa classificação e o da proposta pela Organização Mundial de Saúde (OMS), destacando o papel de outras características histopatológicas no comportamento biológico do CCE de cavidade oral e propondo novas gradações. Neste sentido, as classificações histopatológicas podem prover fatores prognósticos suplementares, a fim de otimizar o valor do estadiamento TNM e auxiliar na escolha terapêutica. Este estudo visa a apresentar os critérios adotados em algumas classificações histopatológicas para o CCE de cavidade oral, amplamente usadas na literatura científica, discutir suas características, ressaltando suas similaridades e discordâncias, além de analisar sua associação com o desfecho do paciente.

Plaquetas: ainda um alvo terapêutico / Platelets: still a therapeutical target

As plaquetas são fragmentos citoplasmáticos anucleados presentes no sangue e produzidos na medula óssea a partir dos megacariócitos. O objetivo deste trabalho é rever as bases mecanísticas e moleculares das plaquetas, revelando sua participação em síndromes importantes e na trombose arterial, além de seu potencial como alvo terapêutico para o desenho de novos agentes antitrombóticos.

Platelets are cytoplasmatic fragments from bone marrow megakaryocytes present on blood. The aim of this work is to review the basis of platelet mechanisms, their participation in syndromes and in arterial thrombosis, and its potential as a target for design of antithrombotic agents.

Cistos e tumores odontogênicos: estudo epidemiológico / Odontogenic cysts and tumors: an epidemiologic study

Os tecidos bucais são alvo de ampla variedade de lesões odontogênicas. O objetivo deste estudo foi avaliar a freqüência com que os cistos e tumores odontogênicos foram diagnosticados na Clínica de Estomatologia da Faculdade de Odontologia da Universidade Federal do Rio de Janeiro (UFRJ) no período de 1986 a 2002. Os dados foram coletados a partir dos prontuários clínicos com confirmação histológica. As seguintes variáveis foram analisadas: diagnóstico definitivo, sexo, faixa etária e localização da lesão. Foram levantados 131 casos, sendo 89 (68 por cento) de cistos e 42 (32 por cento) de tumores odontogênicos. Dentre os cistos odontogênicos, os mais comuns foram os de origem inflamatória, seguidos pelo Cisto Dentígero e Ceratocisto. O tumor odontogênico mais prevalente foi o Odontoma, seguido do Ameloblastoma. Conclui-se que as características encontradas são concordantes com as de outros estudos semelhantes.