Navegando por Palavras-chave "carcinogenesis"
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- ItemSomente MetadadadosAnálise do tempo de sobrevida de doentes com adenocarcinoma colorretal esporádico pela utilização de um painel de biomarcadores de carcinogênese constituído por vegf, egfr, ki-67, p53 e bcl-2(Universidade Federal de São Paulo (UNIFESP), 2014-12-17) Luderer, Loreley Andrade [UNIFESP]; Matos, Delcio Matos [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objective: To evaluate the prognostic power of survival of a carcinogenesis biomarkers panel formed by p53, VEGF, Bcl-2, Ki-67, and EGFR in subjects with sporadic colorectal adenocarcinoma subjected to radical surgical treatment. Methods: 114 post-surgical subjects with colorectal adenocarcinoma were studied and followed for 3 to 5 years at Fundação Pio XII – Hospital de Câncer de Barretos. The study was conducted in paraffin-embedded tumor tissue whose slides were stained using the hematoxylin-eosin technique. The tissue microarray slides, as well as the immunohistochemical staining, were examined by two pathologists, blinded to the evaluations. The statistical analyses were conducted using mean, median, minimum, maximum, and number of valid observations for the descriptive analysis of the numeric variable, global survival. The comparison of the expression of EGFR, VEGF, Ki-67, p53, and Bcl-2 biomarkers was conducted through the Chi-square test or, when required, Fisher’s exact test. The Cox regression model was used for global survival analysis with a panel of markers and for uni and multivariate global survival analyses. Results: Isolated expression correlation results of the markers with the variables: age, differentiation degree, venous invasion, perineural invasion, TNM (I+II) x (III+IV), and survival showed statistically significant differences in the EGFR expression with venous invasion, TNM classification, and global survival; the expression of the VEGF marker has showed significant correlation with the perineural invasion; the Ki-67 marker, with age, venous invasion, and TNM; expression of p53 was significantly related with age, venous invasion, TNM, and global survival; the Bcl-2 marker did not show significant correlation with any of the variables analyzed. The survival analysis, using the markers panel, has significantly showed lesser time of survival in surgical species with 60% or more overexpression. Conclusion: Overexpression of the selected tumor markers panel is related with lesser time of survival in those suffering from sporadic colorectal adenocarcinoma subjected to radical surgical treatment.
- ItemSomente MetadadadosMET Is Highly Expressed in Advanced Stages of Colorectal Cancer and Indicates Worse Prognosis and Mortality(Int Inst Anticancer Research, 2009-11-01) Oliveira, Antonio Talvane Torres de [UNIFESP]; Matos, Delcio [UNIFESP]; Logullo, Angela Flavia [UNIFESP]; Silva, Sandra Regina Morini da [UNIFESP]; Artigiani Neto, Ricardo [UNIFESP]; Longat Filho, Adhemar; Saad, Sarhan Sydney [UNIFESP]; Barretos Canc Hosp; Universidade Federal de São Paulo (UNIFESP); Univ Minho; Universidade de São Paulo (USP)The aim of the present study was to evaluate by immunohistochemistry the prognostic meaning of the tumor marker MET (hepatocyte growth factor) in patients submitted to surgical resection due to primary colorectal adenocarcinoma. Patients and Methods: A retrospective study was carried out that included 286 consecutive patients with colorectal adenocarcinoma, submitted to surgical resection at Barretos Cancer Hospital, from 1993 to 2002. The histopathological expression of the MET tumor marker was evaluated using an anti-protein monoclonal antibody against MET by the streptavidin-biotin-peroxidase technique. The expression of the tumor marker was semi-quantitative, and the slide samples were independently analyzed by three pathologists unaware of patient clinical and histopathological data. Results: The tumor marker expression was positive in 236 (79%) out of a total of 286 patients. This expression was statistically significantly different between stages I and IV (p=0.004), for overall survival (p=0.009), and for cancer-related mortality rates (p=0.022). However, no association between the tumor marker and recurrence (p=0.89) or disease-free interval (p=0.91) was observed. Conclusion: MET has shown significant expression at advanced stages of the disease, as well as for overall survival and cancer-related mortality rates demonstrating to be a valuable marker for poor prognosis in colorectal cancer patients.
- ItemSomente MetadadadosOxidative stress modulates DNA methylation during melanocyte anchorage blockade associated with malignant transformation(Neoplasia Press, 2007-12-01) Campos, Ana Cristina Espindola [UNIFESP]; Molognoni, Fernanda [UNIFESP]; Melo, Fabiana Henrique Machado de [UNIFESP]; Galdieri, Luciano de Camargo [UNIFESP]; Carneiro, Celia Regina Whitaker [UNIFESP]; D'Almeida, Vânia [UNIFESP]; Correa, Mariangela [UNIFESP]; Jasiulionis, Miriam Galvonas [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Both oxidative/nitrosative stress and alterations in DNA methylation are observed during carcinogenesis of different tumor types, but no clear correlation between these events has been demonstrated until now. Melanoma cell lines were previously established after submitting the nontumorigenic melanocyte lineage, melan-a, to cycles of anchorage blockade. in this work, increased intracellular oxidative species and nitric oxide levels, as well as alterations in the DNA methylation, were observed after melan-a detachment, which were also associated with a decrease in intracellular homocysteine (Hcy), an element in the methionine ( universal methyl donor) cycle. This alteration was accompanied by increase in glutathione (GSH) levels and methylated DNA content. Furthermore, a significant increase in dnmt1 and 3b expression was identified along melan-a anchorage blockade. (G)(L)-Nitro-L-arginine methyl esther ((L)-NAME), known as a nitric oxide synthase (NOS) inhibitor, and N-acetyl-(L)-cysteine (NAC) prevented the increase in global DNA methylation, as well as the increase in dnmt1 and 3b expression, observed during melan-a detachment. Interestingly, both (L)-NAME and NAC did not inhibit nitric oxide (NO) production in these cells, but abrogated superoxide anion production during anchorage blockade. in conclusion, oxidative stress observed during melanocyte anchorage blockade seems to modulate DNA methylation levels and may directly contribute to the acquisition of an anoikis-resistant phenotype through an epigenetic mechanism.
- ItemSomente MetadadadosUse of Grape Polyphenols Against Carcinogenesis: Putative Molecular Mechanisms of Action Using in Vitro and in Vivo Test Systems(Mary Ann Liebert Inc, 2013-03-01) Gollucke, Andrea P. B.; Aguiar, Odair [UNIFESP]; Barbisan, Luis Fernando; Ribeiro, Daniel Araki [UNIFESP]; Univ Catolica Santos; Universidade Federal de São Paulo (UNIFESP); São Paulo State UnivPolyphenols are present in foods and beverages and are related to sensorial qualities such as color, bitterness, and astringency, which are relevant in wine, tea, grape juice, and other products. These compounds occur naturally in forms varying from simple phenolic acids to complex polymerized tannins. Thus, it is reasonable to expect that grape-derived products elaborated in the presence of skins and seeds, such as wine and grape juice, are natural sources of flavonoids in the diet. Carcinogenesis is a multistep process that is characterized by genetic, epigenetic, and phenotypic changes. With increasing knowledge of these mechanisms, and the conclusion that most cases of cancer are preventable, efforts have focused on identifying the agents with potential anticancer properties. the use of grape polyphenols against the carcinogenesis process seems to be a suitable alternative for either prevention and/or therapeutic purposes. the aim of this article is to show the molecular data generated from the use of grape polyphenols against carcinogenesis using in vivo and in vitro test systems.