Navegando por Autor "LIMA, Eleonidas Moura"

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Acesso aberto (Open Access)
Cytogenetic description of breast fibroadenomas: alterations related solely to proliferation?
(2001-08) BURBANO, Rommel Mario Rodriguéz; LIMA, Eleonidas Moura; KHAYAT, André Salim; BARBIERI Neto, J.; CABRAL, Isabel Rosa; BASTOS JR., L.; BAHIA, Marcelo de Oliveira; CASARTELLI, Cacilda
Twelve breast fibroadenomas were analyzed cytogenetically and only four were found to have clonal alterations. The presence of chromosomal alterations in fibroadenomas must be the consequence of the proliferating process and must not be related to the etiology of this type of lesion. In contrast, the few fibroadenomas that exhibit chromosomal alterations are likely to be those presenting a risk of neoplastic transformation. Clonal numerical alterations involved chromosomes 8, 18, 19, and 21. Of the chromosomal alterations found in the present study, only monosomy of chromosomes 19 and 21 has been reported in breast fibroadenomas. The loss of chromosome 21 was the most frequent alteration found in our sample. The study of benign proliferations and their comparison with chromosome alterations in their malignant counterparts ought to result in a better understanding of the genes acting on cell proliferation alone, and of the genes that cause these cells to exhibit varied behaviors such as recurrences, spontaneous regression and fast growth.
Acesso aberto (Open Access)
Dideoxy single allele-specific PCR - DSASP new method to discrimination allelic
(Universidade Federal do Pará, 2015-06) LIMA, Eleonidas Moura; LOPES, Otávio Sérgio; SOARES, Leonardo Ferreira; ARRUDA, Talitta Dantas; GIGEK, Carolina Oliveira; MELO, Cynthia Germoglio Farias; SMITH, Marília de Arruda Cardoso; OLIVEIRA, João Ricardo Gonçalves; MEDEIROS, Arnaldo Correia de; DELATORRE, Plínio; BURBANO, Rommel Mario Rodriguéz
Gastric cancer (GC) is a multifactorial disease with a high mortality rate in Brazil and worldwide. This work aimed to evaluate single nucleotide polymorphisms (SNP) rs1695, in the Glutathione S-Transferase Pi (GSTP1) gene in GC samples by comparative analysis Specific PCR - ASP and Dideoxy Single Allele-Specific PCR - DSASP methods. The DSASP is the proposed new method for allelic discrimination. This work analyzed 60 GC samples, 26 diffuse and 34 intestinal types. The SNP rs1695 of the GSTP1 gene was significantly associated with GC analyzed by DSASP method (χ 2 = 9.7, P < 0.05). A comparative analysis of the data obtained from both methods did not differ significantly (χ 2 = 0.08, P > 0.05). These results suggest that the SNP rs1695 of the GSTP1 gene was a risk factor associated with gastric carcinogens is and the DSASP method was a new successfully low-cost strategy to study allelic discrimination.
Acesso aberto (Open Access)
Methylation status of ANAPC1, CDKN2A and TP53 promoter genes in individuals with gastric cancer
(2008-06) LIMA, Eleonidas Moura; LEAL, Mariana Ferreira; BURBANO, Rommel Mario Rodriguéz; KHAYAT, André Salim; ASSUMPÇÃO, Paulo Pimentel de; BELLO, Maria Josefa; HERRANZ, Juan Antonio Rey; SMITH, Marília de Arruda Cardoso; CASARTELLI, Cacilda
Gastric cancer is the forth most frequent malignancy and the second most common cause of cancer death worldwide. DNA methylation is the most studied epigenetic alteration, occurring through a methyl radical addition to the cytosine base adjacent to guanine. Many tumor genes are inactivated by DNA methylation in gastric cancer. We evaluated the DNA methylation status of ANAPC1, CDKN2A and TP53 by methylation-specific PCR in 20 diffuse- and 26 intestinal-type gastric cancer samples and 20 normal gastric mucosa in individuals from Northern Brazil. All gastric cancer samples were advanced stage adenocarcinomas. Gastric samples were surgically obtained at the João de Barros Barreto University Hospital, State of Pará, and were stored at -80°C before DNA extraction. Patients had never been submitted to chemotherapy or radiotherapy, nor did they have any other diagnosed cancer. None of the gastric cancer samples presented methylated DNA sequences for ANAPC1 and TP53. CDKN2A methylation was not detected in any normal gastric mucosa; however, the CDKN2A promoter was methylated in 30.4% of gastric cancer samples, with 35% methylation in diffuse-type and 26.9% in intestinal-type cancers. CDKN2A methylation was associated with the carcinogenesis process for ~30% diffuse-type and intestinal-type compared to non-neoplastic samples. Thus, ANAPC1 and TP53 methylation was probably not implicated in gastric carcinogenesis in our samples. CDKN2A can be implicated in the carcinogenesis process of only a subset of gastric neoplasias.