927 resultados para Renal Cell Carcinoma


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Introdução: Recentemente o papilomavírus humano (HPV) tem sido associado à carcinogênese oral. A metodologia empregada na detecção do vírus é uma das maiores causas observadas da grande variabilidade nas taxas de detecção do HPV. Objetivo: Este estudo comparou a sensibilidade de detecção do DNA do HPV em casos de carcinoma epidermoide de lábio utilizando a amplificação do DNA viral por reação em cadeia da polimerase (PCR) ou nPCR. Material e método: Foram utilizadas 33 amostras provenientes de casos de carcinoma epidermoide de lábio. Para as extrações do DNA utilizou-se o sistema QIAamp DNA Mini Kit. Como controle interno utilizou-se o gene da b-globina. Das 33 amostras iniciais, 30 foram positivas para o gene b-globina, sendo utilizadas para detectar o DNA viral. Comparou-se a amplificação do DNA viral pelos métodos da PCR com os oligonucleotídeos MY09/MY11 e nPCR, empregando-se os pares de oligonucleotídeos iniciadores MY09/MY11 e, na segunda etapa, o par GP5+/GP6+. O controle positivo para a presença do DNA do HPV utilizado foi a linhagem de células HeLa e, como controle negativo, a mistura de amplificação sem DNA. A análise dos produtos de PCR e nPCR para HPV foi realizada por eletroforese em gel de poliacrilamida a 8%. Resultados: Utilizando-se o método da PCR, a amplificação do DNA do HPV foi constatada em dois casos. Com a nPCR foi verificada presença de DNA viral em 13 das 30 amostras. Conclusão: Com a utilização da nPCR, a detecção do HPV nos casos estudados aumentou mais de seis vezes.

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Objective, the objective of this study was to evaluate the reliability of in vivo staining with toluidine blue in the detection of oral epithelial dysplasia, in situ carcinoma, and invasive squamous cell carcinomas in potentially malignant epithelial lesions (PMELs) and superficial oral ulcerations suggesting malignancy.Study design. Fifty patients with PMELs and superficial oral ulcerations suggestive of malignancy were selected from those treated at the Oral Medicine Service, Faculty of Dentistry, Araraquara, Brazil. All lesions were submitted to staining with an aqueous solution of 1% toluidine blue, followed by biopsy and histologic analysis. The sensitivity, specificity, and positive and negative predictive values were calculated.Results. Histologic diagnosis revealed that 14% of the lesions analyzed were in situ carcinoma and invasive squamous cell carcinomas, 12% were epithelial dysplasias, 13% were keratosis, 40% were lichen planus, and 8% were other benign lesions. The sensitivity uf the staining was 77%, the specificity 67%, and the positive and negative predictive values 43.5% and 88.9%, respectivelyConclusions, Staining with toluidine blue was demonstrated to be highly reliable in the detection of in situ carcinoma acid invasive squamous cell carcinoma, because false-negative results for the lesions did not occur. Toluidine blue staining is an adjunct to clinical judgment and not a substitute for either judgment or biopsy.

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Background. Loss of heterozygosity (LOH) correlates with inactivated tumor suppressor genes. LOH at chromosome arm 22q has been found in a variety of human neoplasms, suggesting that this region contains a tumor suppressor gene(s) other than NF2 important to tumorigenesis. The aim of this study was to evaluate the presence of LOH on chromosome 22q11.2-13 and determine whether there was a relationship between loss in this genomic region and tumor histologic parameters, anatomic site, and survival in patients with squamous cell carcinoma of the head and neck (HNSCC).Methods. Fifty matched blood and HNSCC tumor samples taken at the time of surgical treatment were evaluated for LOH by use of four microsatellite markers mapping to 22q11.2-q13. Clinical information was available for all patients. The frequency and distribution of LOH was correlated with clinical (age, sex, use of tobacco and alcohol, site of primary tumor, clinical stage, adjuvant therapy and overall survival) and histologic parameters (histopathologic stage, tumor differentiation).Results. LOH at 22q was found in 19 of 50 (38%) informative tumors. The respective incidence of allelic loss for the patients was as follows: 28% at D22S421, 10% at D22S277, 8% at D22S44S, and 4% at D22S280. No statistical differences were apparent with a mean follow-up of 30 months. Laryngeal tumors showed a higher incidence of LOH compared with oral tumors.Conclusions. These results suggest that the D22S277 locus may be closely linked to a tumor suppressor gene (TSG) and involved in upper aerodigestive tract carcinogenesis. In particular, laryngeal tumors may harbor another putative TSG on 22q11.2-q12.3 that may play a role in aggressive stage III/IV disease. (C) 2000 John Wiley & Sons, Inc.

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MicroRNAs (miRs) are non-coding RNA molecules involved in cancer initiation and progression. Deregulated miR expression has been implicated in cancer; however, there are no studies implicating an miR signature associated with progression in oral squamous cell carcinoma (OSCC). Although OSCC may develop from oral leukoplakia, clinical and histological assessments have limited prognostic value in predicting which leukoplakic lesions will progress. Our aim was to quantify miR expression changes in leukoplakia and same-site OSCC and to identify an miR signature associated with progression. We examined miR expression changes in 43 sequential progressive samples from 12 patients and four non-progressive leukoplakias from four different patients, using TaqMan Low Density Arrays. The findings were validated using quantitative RT-PCR in an independent cohort of 52 progressive dysplasias and OSCCs, and five non-progressive dysplasias. Global miR expression profiles distinguished progressive leukoplakia/OSCC from non-progressive leukoplakias/normal tissues. One hundred and nine miRs were highly expressed exclusively in progressive leukoplakia and invasive OSCC. miR-21, miR-181b and miR-345 expressions were consistently increased and associated with increases in lesion severity during progression. Over-expression of miR-21, miR-181b and miR-345 may play an important role in malignant transformation. Our study provides the first evidence of an miR signature potentially useful for identifying leukoplakias at risk of malignant transformation.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The efficacy of fluorescence spectroscopy to detect squamous cell carcinoma is evaluated in an animal model following laser excitation at 442 and 532 nm. Lesions are chemically induced with a topical DMBA application at the left lateral tongue of Golden Syrian hamsters. The animals are investigated every 2 weeks after the 4th week of induction until a total of 26 weeks. The right lateral tongue of each animal is considered as a control site (normal contralateral tissue) and the induced lesions are analyzed as a set of points covering the entire clinically detectable area. Based on fluorescence spectral differences, four indices are determined to discriminate normal and carcinoma tissues, based on intraspectral analysis. The spectral data are also analyzed using a multivariate data analysis and the results are compared with histology as the diagnostic gold standard. The best result achieved is for blue excitation using the KNN (K-nearest neighbor, a interspectral analysis) algorithm with a sensitivity of 95.7% and a specificity of 91.6%. These high indices indicate that fluorescence spectroscopy may constitute a fast noninvasive auxiliary tool for diagnostic of cancer within the oral cavity. (C) 2008 Society of Photo-Optical Instrumentation Engineers.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Objectives. This study was undertaken to evaluate the expression of p53, Ki-67, and CD31 both in the tumor and in the vaginal margins of radical hysterectomy in patients with stage IB squamous cell carcinoma of the cervix, as an attempt to use these proteins as possible markers for residual tumor in cervical cancer.Methods. Thirty patients with stage IB squamous cell carcinoma of the cervix were submitted to radical hysterectomy (study group), and thirty patients with uterine myoma were submitted to vaginal hysterectomy (control group) and were prospectively studied from November 2001 to September 2002. Tissue samples were taken from the tumor or cervix, anterior vaginal margin (AVM), and posterior vaginal margin (PVM) and were immunohistochemically evaluated by monoclonal antibodies for p53, Ki-67, and CD31. Vaginal samples in which the histological examination showed tumor involvement were excluded from the study.Results. Patient's mean age was 48.7 +/- 10.4 years (27-73 years). The clinical stage was IB1 in 22 patients (73.3%) and IB2 in eight patients (26.7%). The expressions of p53, Ki-67, and CD31 were significantly higher in the tumor than in the benign cervix (P < 0.001). Higher expressions of these markers were noted in the vaginal margins of radical hysterectomy in patients with cervical carcinoma compared to the vaginal margins of control patients. This association was demonstrated for p53 in the AVM proximal (P = 0.045), for Ki-67 in AVM proximal (P < 0.001), AVM distal (P < 0.001), PVM proximal (P = 0.009), and PVM distal (P < 0.001), and for CD31 in AVM proximal (P = 0.003) and AVM distal (P = 0.018). There was no difference in p53, Ki-67, and CD31 expression between the proximal and distal regions of the vaginal margins in patients with carcinoma of the cervix.Conclusion. The expressions of p53, Ki-67, and CD31 were significantly higher in both the histologically positive (cervical tumor) and negative (vaginal margins) tissues of patients who had undergone radical hysterectomy for cervical cancer compared to the benign control tissues. (C) 2004 Elsevier B.V. All rights reserved.

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Abnormalities in any component of the cell cycle regulatory machine may result in oral. cancer, and markers of cell proliferation have been used to determine the prognosis of tumor progression. The aim of this study was to determine whether silver-stained nucleolar organizer region (AgNOR) and Ki-67 measurements could improve the assessment of growth rates in oral lesions. Eighty-three oral biopsies were studied, 20 of which were classified as fibrous inflammatory hyperplasia (FIH), 40 as leukoplakia (LKP) and 23 as oral. squamous cell carcinoma (OSCC). Within the LKP group, 22 out of 29 biopsies were diagnosed as non-dysplastic leukoplakia (LK) and 18 as dysplastic teukoptakia (DLK), presenting discrete, moderate and severe dysplasia. Ki-67 immunotabeting of the lesions increased steadily in the following order: FIH, DLK, LK and OSCC, indicating that Ki-67 is a good marker for predicting the protiferative fraction among benign, premalignant and malignant oral lesions. The median values of AgNOR parameters indicate that the morphometric index gives better results regarding the proliferative rate than the numerical one. A series of linear regressions between AgNOR parameters and Ki-67 showed positive associations. We conclude that a combination of Ki-67 and morphometric AgNOR analyses could be used as an aid in the determination of the protiferative status of oral epithelial. cells in oral cancer. (C) 2007 Elsevier GmbH. All rights reserved.

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Purpose: This study was undertaken to evaluate clinical and pathologic findings that predicted pelvic lymph node metastasis and parametrial and vaginal involvement in patients with stage IB carcinoma of the cervix. Methods: 71 patients with diagnosis of stage IB (FIGO) cervical cancer were prospectively studied from December 1997 to August 2002. The patient's age, clinical stage (IB1 or IB2), histological classification, grade of differentiation, tumor volume, and lymphatic vascular space invasion (LVSI) were evaluated. Statistical methods included chi(2) test and Fisher's exact test to evaluate significant differences between the groups. The level of significance was set at p < 0.05. Results: the clinical stage was IB1 in 51 patients (71.8%) and IB2 in 20 patients (28.2%). The histological classification identified squamous cell carcinoma in 60 patients (84.5%) and adenocarcinoma in 11 patients (15.5%). The average tumoral volume was 22.8 &PLUSMN; 8 24.3 cm(3) (0.3-140.0 cm(3)). The tumor was well differentiated (G1) in 8 (11.3%), moderately differentiated (G2) in 40 (56.3%) and poorly differentiated in 23 (32.4%) of the cases. The presence of LVSI was detected in 14 patients (19.7%) and was associated with pelvic lymph node metastasis and vaginal and parametrial involvement (p = 0.002, p = 0.001 and p < 0.001; respectively). The average number of positive pelvic lymph nodes was significantly higher in the patients with LVSI compared with patients without LVSI (2.47 +/- 2.8 vs. 0.33 +/- 0.74; p = 0.001). There was no association of age, clinical stage, histological classification, grade of differentiation or tumor volume with pelvic lymph node metastasis and vaginal and parametrial involvement. Conclusion: the presence of LVSI is significantly associated with pelvic lymph node metastasis and vaginal and parametrial involvement in patients with stage IB cervical carcinoma. Copyright (C) 2005 S. Karger AG, Basel.

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Patients with chagasic achalasia (megaesophagus) are liable to have an additional 1.7-20% possibility of developing esophageal squamous cell carcinoma (ESCC). We applied a fluorescence in situ hybridization technique in 20 such patients and found aneuploidies of chromosomes 7, 11, and 17 in 60% (12 of 20 specimens) and deletion of the TP53 gene in 54.5% (6 of 11 specimens; it was only possible to obtain data by FISH technique from 11 of the 20 achalasia patients). The main aneuploidies detected were chromosome 7 monosomy or trisomy (35%) in mid-third megaesophagus cases, and chromosome 17 monosomy or trisomy (25%) in distal-third cases. TP53 gene deletion was more frequent in mid-third (62.5%) than in distal-third megaesophagus cases (40%). In chagasic megaesophagus, no amplification of the cyclin D1 gene (CCND1) was observed. Comparing chagasic megaesophagus to ESCC, we found a higher frequency of aneuploidies in all 10 tumors. The main alterations were trisomy or tetrasomy of chromosomes 17 (90%), 11 (70%), and 7 (70%). Amplification of CCND1 was evidenced as a cluster in 70% of the tumors (22-99% of nuclei), while TP53 gene deletion occurred in 100%. To our knowledge, this is the first cytogenetic analysis of chagasic megaesophagus to show that aneuploidies of chromosomes 7, 11, and 17, and TP53 gene deletion might be related to increased risk for malignancy. (C) 2004 Elsevier B.V. All rights reserved.

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Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa front 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/ Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors. (C) 2004 Elsevier B.V. All rights reserved.