RESUMEN
BACKGROUND: Sinonasal intestinal-type adenocarcinomas (ITACs) have a poor prognosis, and are defined on the basis of their morphological similarities to colorectal adenocarcinomas. MET signaling pathway is involved in oncogenesis in various cancers. Nothing is currently known about the role of MET in ITACs. METHODS: In a series of 72 ITACs, we investigated MET protein levels by immunohistochemistry (IHC) and gene copy number by in situ hybridization. These findings were analyzed as a function of clinical data, histological typing, and patient outcome. RESULTS: MET protein was overproduced in 64% of cases and chromosome 7 polysomy was observed in 52% of cases. No tumor displayed MET amplification. The presence of mucinous or solid histological components, T3/T4 tumors, and incomplete resection were associated with a poor outcome. CONCLUSION: MET is overproduced in about two third of ITACs, suggesting a role for the MET signaling pathway in the oncogenesis of these tumors.
Asunto(s)
Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Biomarcadores de Tumor/metabolismo , Neoplasias Intestinales/mortalidad , Neoplasias Intestinales/patología , Proteínas Proto-Oncogénicas c-met/genética , Adenocarcinoma/genética , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Dosificación de Gen , Regulación Neoplásica de la Expresión Génica , Humanos , Hibridación in Situ , Neoplasias Intestinales/genética , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Modelos de Riesgos Proporcionales , Proteínas Proto-Oncogénicas c-met/metabolismo , Estudios Retrospectivos , Transducción de Señal , Estadísticas no Paramétricas , Análisis de SupervivenciaRESUMEN
BACKGROUND: The alpha-internexin (INA) gene encodes an intermediate filament involved in neurogenesis and maps in 10q24.33. A strong INA protein expression has been reported in oligodendroglial tumours and was associated with 1p19q deletion. To assess the relevance of INA immunohistochemistry in glioma typing, this paper studied the relationship between INA expression, histological type, genomic status and patient outcome. METHODS: The study analysed INA, nestin, Olig2 and p53 expression, loss of heterozygosity of microsatellite markers from telomere to centromere of 10p, 10q, 1p and 19q chromosomes and epidermal growth factor receptor gene (EGFR) amplification in 40 gliomas (five astrocytomas, 12 oligodendrogliomas, 11 oligoastrocytomas, 12 glioblastomas). INA expression was scored as absent, weak (<10% of labelled tumour cells) or strong (>10%). RESULTS: Oligodendrogliomas showed strong INA and Olig2 expression, and 1p19q whole loss of heterozygosity (wLOH). Astrocytomas and glioblastomas were characterised by no or weak INA expression, high p53 and nestin expression, 10p10q wLOH, and epidermal growth factor receptor amplification. Most oligoastrocytomas had characteristics of astrocytic tumours. All tumours with strong INA expression retained the 10q chromosome arm and, except for one, had a 1p19q wLOH status. However, despite a strong link between INA expression, 1p19q wLOH and 10q retention, discrepancies were observed in 10% of cases. The presence of INA expression, whether weak or strong, was related to a better prognosis. CONCLUSION: INA expression study can be helpful for glioma typing and prognosis determination in combination with other markers. Nevertheless, INA immunohistochemistry cannot replace the genomic analysis to determine 1p19q and 10p10q status.
