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©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
Interrelationship between chromosome 8 aneuploidy, C-MYC amplification and increased expression in individuals from northern Brazil with gastric adenocarcinoma
Danielle Queiroz Calcagno, Mariana Ferreira Leal, Aline Damaceno Seabra, André Salim Khayat, Elizabeth Suchi Chen, Samia Demachki, Paulo Pimentel Assumpção, Mario Henrique Girão Faria, Silvia Helena Barem Rabenhorst, Márcia Valéria Pitombeira Ferreira, Marília de Arruda Cardoso Smith, Rommel Rodríguez Burbano
Danielle Queiroz Calcagno, Aline Damaceno Seabra, André Salim Khayat, Rommel Rodríguez Burbano, Human Cytogenetics and Toxicological Genetics Laboratory, Department of Biology, Center of Biological Sciences, Federal University of Pará, Belém, PA, Brazil
Mariana Ferreira Leal, Elizabeth Suchi Chen, Marília de Arruda Cardoso Smith, Rommel Rodríguez Burbano, Genetics Division, Department of Morphology, Federal University of São Paulo, São Paulo, SP, Brazil
Samia Demachki, Department of Pathology and Surgery Service, Federal University of Pará, Belém, PA, Brazil
Paulo Pimentel Assumpção, João de Barros Barreto University Hospital, Federal University of Pará, Belém, PA, Brazil
Mario Henrique Girão Faria, Silvia Helena Barem Rabenhorst, Márcia Valéria Pitombeira Ferreira, Molecular Genetics Laboratory Department of Pathology, Medical School, Federal University of Ceará, Fortaleza, CE, Brazil
Supported by Financiadora de Estudos e Projetos (FINEP CT-INFRA/FADESP), No. 0927-03 and Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) No. 2003/06540-5; DQC had a master fellowship, No. 151127/2002-6, granted by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Correspondence to: Rommel Rodríguez Burbano, Laboratório de Citogenética Humana e Genética Toxicológica, Departamento de Biologia, Centro de Ciências Biológicas, Universidade Federal do Pará, Campus Universitário do Guamá, Av. Augusto Correa, 01, CEP 66075-900, Belém, PA, Brazil. rommel@ufpa.br
Telephone: +55-91-2111727 Fax: +55-91-2111601
Received: May 12, 2006
Revised: May 28, 2006
Accepted: June 16, 2006
Published online: October 14, 2006
AIM: To investigate chromosome 8 numerical aberrations, C-MYC oncogene alterations and its expression in gastric cancer and to correlate these findings with histopathological characteristics of gastric tumors.
METHODS: Specimens were collected surgically from seven patients with gastric adenocarcinomas. Immunostaining for C-MYC and dual-color fluorescence in situ hybridization (FISH) for C-MYC gene and chromosome 8 centromere were performed.
RESULTS: All the cases showed chromosome 8 aneuploidy and C-MYC amplification, in both the diffuse and intestinal histopathological types of Lauren. No significant difference (P < 0.05) was observed between the level of chromosome 8 ploidy and the site, stage or histological type of the adenocarcinomas. C-MYC high amplification, like homogeneously stained regions (HSRs) and double minutes (DMs), was observed only in the intestinal-type. Structural rearrangement of C-MYC, like translocation, was observed only in the diffuse type. Regarding C-MYC gene, a significant difference (P < 0.05) was observed between the two histological types. The C-MYC protein was expressed in all the studied cases. In the intestinal-type the C-MYC immunoreactivity was localized only in the nucleus and in the diffuse type in the nucleus and cytoplasm.
CONCLUSION: Distinct patterns of alterations between intestinal and diffuse types of gastric tumors support the hypothesis that these types follow different genetic pathways.
