title: Alterations of MEN1 and E-cadherin/β-catenin complex in sporadic pulmonary carcinoids.
abstract: Pulmonary carcinoids, distinct in typical and atypical, represent 2-5% of all primary lung tumors. The aim of this study was to investigate the molecular alterations correlated with the development of this form of neoplasms. A collection of 38 paraffin-embedded apparently sporadic carcinoids was investigated, through a combined study, for protein expression/localization of menin, p53, β-catenin and E-cadherin and for mutational analysis of the MEN1, TP53 and CTNNB1 genes. Menin was expressed in 71% of cases, with a prevalent cytoplasmic (c) localization, β-catenin was expressed in 68.4% of cases, of which 36.8% with a membranous (m) and 31.6% with a cytoplasmic localization. Membranous E-cadherin immunoreactivity was detected in 84.2% cases, nuclear p53 expression in 5.3% of cases. Positive correlation was found between c-menin and c-β-catenin expression (rho=0.439, P=0.008). In addition, m-β-catenin showed a positive correlation with both c-β-catenin and E-cadherin expression (rho=0.380, P=0.022 and rho=0.360, P=0.040, respectively). With regard to the E-cadherin/β-catenin complex, we found also a significant positive correlation between c-menin and 'disarrayed' β-catenin expression (rho=0.481, P=0.007). MEN1 gene variants were characterized in 34% of cases. c-menin was more highly expressed in tumors with MEN1 variants, compared to tumors without MEN1 variants (P=0.023). Three nucleotide variants of TP53 were also detected. This study confirms the involvement of the MEN1 gene in the development of sporadic pulmonary carcinoids, demonstrates the accumulation of menin in the cytoplasm, and indicates that the disarrayed pattern of the complex significantly correlates with c-menin accumulation.
authors: Department of Experimental and Clinical Sciences, University 'G. d'Annunzio'-Chieti-Pescara, I-66013 Chieti, Italy.
authors: Serena
authors: S
authors: Veschi
authors: Rossano
authors: R
authors: Lattanzio
authors: Gitana Maria
authors: GM
authors: Aceto
authors: Maria Cristina
authors: MC
authors: Curia
authors: Salvatore
authors: S
authors: Magnasco
authors: Domenico
authors: D
authors: Angelucci
authors: Alessandro
authors: A
authors: Cama
authors: Mauro
authors: M
authors: Piantelli
authors: Pasquale
authors: P
authors: Battista
mesh_terms: D015820:Cadherins / Q000096:biosynthesis*; D002276:Carcinoid Tumor / Q000235:genetics* / Q000473:pathology; D003593:Cytoplasm / Q000235:genetics / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D015534:Trans-Activators / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis; D051176:beta Catenin / Q000096:biosynthesis*
chemical_list: C495270:CTNNB1 protein, human; D015820:Cadherins; C105373:MEN1 protein, human; D011518:Proto-Oncogene Proteins; C495901:TP53 protein, human; D015534:Trans-Activators; D016159:Tumor Suppressor Protein p53; D051176:beta Catenin