RESUMO

BACKGROUND: Young patients are thought to develop gastric carcinomas with a molecular genetic profile that is distinct from that of gastric carcinomas occurring at a later age. The aim of this study was to compare the clinicopathological features and expression patterns of the markers E-cadherin and beta-catenin, and mucins (MUC1, MUC2, MUC5AC, and MUC6) in young and older patients. METHODS: The clinicopathological features and overall survival data of 62 young patients (age 40 years). A tissue microarray method and immunohistochemistry were used in order to analyze marker expression in paraffin-embedded tissue blocks obtained from both groups. RESULTS: The young group presented a higher percentage of diffuse-type tumors in comparison to the older group (P<0.01). The rates of positivity for E-cadherin and beta-catenin membranous expression patterns and mucin (MUC2, MUC5AC and MUC6) positivity were higher in the young group (P<0.01). Although young patients showed a lower frequency of alterations in marker expression and had significantly better survival rates than the older patients, neither age nor the marker expression pattern were found to be independent prognostic factors of survival. Only stage, tumor size, and tumor location persisted as prognostic factors for patients with gastric cancer. CONCLUSION: Biological markers of cellular adhesion and gastric differentiation were differently expressed in young and older patients. Our findings support the hypothesis that young patients develop carcinomas with a different genetic pathway compared to the pathway of tumors occurring at a later age, and we suggest further investigations to assess the prognostic relevance of the markers to specific subgroups.

Assuntos

Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adulto , Fatores Etários , Biomarcadores Tumorais/genética , Caderinas/genética , Caderinas/metabolismo , Adesão Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Mucina-5AC/genética , Mucina-5AC/metabolismo , Mucina-1/genética , Mucina-1/metabolismo , Mucina-2/genética , Mucina-2/metabolismo , Mucina-6/genética , Mucina-6/metabolismo , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Taxa de Sobrevida , beta Catenina/metabolismo

RESUMO

Objectives: This study aimed to evaluate the expression pattern of some markers (E-cadherin and â-catenin) related to cellular adhesion and their relationship with histological tumor type according to Laurén’s system, clinicopathological features and patient survival. Material and Methods: We did immunohistochemical analysis in a retrospective series of 446 gastric carcinomas using tissue microarray method (TMA). Clinicopathological features and overall survival data of all patients were retrospectively reviewed from hospital records. For all statistical analyses, p<0.05 was considered significant. Results: The reduced/absent expression of E-cadherin occurred more frequently in diffuse than intestinal type tumors and it was correlated with worse biological behavior and poor prognosis for patients with diffuse type gastric carcinomas. The pattern of â-catenin expression was closely related to histological type and E-cadherin expression. Although patients with nuclear/absent â-catenin immunoreactivity showed worse survival index, no statistical correlation was found with overall survival. In multivariated analysis, only pTNM staging system persisted as independent prognostic marker. Conclusion: In the present study, alterations in E-cadherin/â-catenin complex expression showed significant correlations with clinicopathological parameters, as well as its implications for tumor progression and prognosis in gastric cancer. Our results indicate that markers expression pattern may be a useful marker of differentiation and suggest further investigations of their prognostic relevance to specific histological groups.

Assuntos

Humanos , Padrões de Referência , Neoplasias Gástricas , beta Catenina , Sobrevida