24 research outputs found
The Menin Tumor Suppressor Protein Is Phosphorylated in Response to DNA Damage
Multiple endocrine neoplasia type 1 (MEN1) is a heritable cancer syndrome characterized by tumors of the pituitary, pancreas and parathyroid. Menin, the product of the MEN1 gene, is a tumor suppressor protein that functions in part through the regulation of transcription mediated by interactions with chromatin modifying enzymes.Here we show menin association with the 5' regions of DNA damage response genes increases after DNA damage and is correlated with RNA polymerase II association but not with changes in histone methylation. Furthermore, we were able to detect significant levels of menin at the 3' regions of CDKN1A and GADD45A under conditions of enhanced transcription following DNA damage. We also demonstrate that menin is specifically phosphorylated at Ser394 in response to several forms of DNA damage, Ser487 is dynamically phosphorylated and Ser543 is constitutively phosphorylated. Phosphorylation at these sites however does not influence the ability to interact with histone methyltransferase activity. In contrast, the interaction between menin and RNA polymerase II is influenced by phosphorylation, whereby a phospho-deficient mutant had a higher affinity for the elongating form of RNA polymerase compared to wild type. Additionally, a subset of MEN1-associated missense point mutants, fail to undergo DNA damage dependent phosphorylation.Together, our findings suggest that the menin tumor suppressor protein undergoes DNA damage induced phosphorylation and participates in the DNA damage transcriptional response
Italian Association of Clinical Endocrinologists (AME) position statement: a stepwise clinical approach to the diagnosis of gastroenteropancreatic neuroendocrine neoplasms
Estimating optimal dose of twice-weekly gemcitabine for concurrent chemoradiotherapy in unresectable pancreatic carcinoma: mature results of GEMRT-01 phase I trial
Adrenal involvement in MEN1. Analysis of 715 cases from the Groupe d'etude des Tumeurs Endocrines database.
Objective Limited data regarding adrenal involvement in multiple endocrine neoplasia type 1 (MEN1) is available. We describe the characteristics of MEN1-associated adrenal lesions in a large cohort to provide a rationale for their management. Methods Analysis of records from 715 MEN1 patients from a multicentre database between 1956 and 2008. Adrenal lesions were compared with those from a multicentre cohort of 144 patients with adrenal sporadic incidentalomas. Results Adrenal enlargement was reported in 20.4% (146/715) of patients. Adrenal tumours (>10 mm in size) accounted for 58.1% of these cases (10.1% of the whole patient cohort). Tumours were bilateral and >40 mm in size in 12.5 and 19.4% of cases respectively. Hormonal hypersecretion was restricted to patients with tumours and occurred in 15.3% of them. Compared with incidentalomas, MEN1-related tumours exhibited more cases of primary hyperaldosteronism, fewer pheochromocytomas and more adrenocortical carcinomas (ACCs; 13.8 vs 1.3%). Ten ACCs occurred in eight patients. Interestingly, ACCs occurred after several years of follow-up of small adrenal tumours in two of the eight affected patients. Nine of the ten ACCs were classified as stage I or II according to the European Network for the Study of Adrenal Tumors. No evident genotype/phenotype correlation was found for the occurrence of adrenal lesions, endocrine hypersecretion or ACC. Conclusions Adrenal pathology in MEN1 differs from that observed in sporadic incidentalomas. In the absence of relevant symptoms, endocrine biology can be restricted to patients with adrenal tumours and should focus on steroid secretion including the aldosterone-renin system. MEN1 is a high-risk condition for the occurrence of ACCs. It should be considered regardless of the size of the tumour
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterised by tumours of the parathyroids, pancreas and anterior pituitary that represents one of the familial cancer syndromes. The MEN1 locus has been previously localised to chromosome 11q13, and a < 300 kb gene-rich region flanked centromerically by PYGM and telomerically by D11S1783 defined by combined meiotic and tumour deletion mapping studies. Two candidate genes, ZFM1 and PPP2R5B,from this region have been previously excluded, and in order to identify additional candidate genes we used a BAC to isolate cDNAs from a bovine parathyroid cDNA library by direct selection. One of the novel genes that we identified, SCG2, proved to be identical to the recently published MEN1 gene, which is likely to be a tumour suppressor gene. The SCG2 transcript was 2.9 kb in all tissues with an additional 4.2 kb transcript also being present in the pancreas and thymus. Mutational analysis of SCG2 in 10 unrelated MEN1 families identified one polymorphism and nine different heterozygous mutations (one missense, four non-sense, one insertional and three deletional frameshifts) that segregated with the disease, hence providing an independent confirmation for the identification of the MEN1 gene
Construction of a 1.2-Mb sequence-ready contig of chromosome 11q13 encompassing the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1.
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant familial cancer syndrome characterized by parathyroid, pancreatic, and anterior pituitary tumors. The MEN1 locus has been previously localized to chromosome 11q13, and a 2-Mb gene-rich region flanked by D11S1883 and D11S449 has been defined. We have pursued studies to facilitate identification of the MEN1 gene by narrowing this critical region to a 900-kb interval between the VRF and D11S1783 loci through melotic mapping. This was achieved by investigating 17 cosmids for microsatellite polymorphisms, which defined two novel polymorphisms at the VRF and A0138 loci, and utilizing these to characterize recombinants in MEN1 families. In addition, we have established a 1200-kb sequence-ready contig consisting of 26 cosmids, eight BACs, and eight PACs that encompass this region. The precise locations for 19 genes and three ESTs within this contig have been determined, and three gene clusters consisting of a centromeric group (VRF, FKBP2, PNG, and PLCB3), a middle group (PYGM, ZFM1, SCG1, SCG2 (which proved to be the MEN1 gene), and PPP2R5B), and a telomeric group (H4B, ANG3, ANG2, ANG1, FON, FAU, NOF, NON, and D11S2196E) were observed. These results represent a valuable transcriptional map of chromosome 11q13 that will help in the search for disease genes in this region
La carrera de veterinaria tiene que volver a ser de seis cursos
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterised by tumours of the parathyroids, pancreas and anterior pituitary that represents one of the familial cancer syndromes. The MEN1 locus has been previously localised to chromosome 11q13, and a < 300 kb gene-rich region flanked centromerically by PYGM and telomerically by D11S1783 defined by combined meiotic and tumour deletion mapping studies. Two candidate genes, ZFM1 and PPP2R5B,from this region have been previously excluded, and in order to identify additional candidate genes we used a BAC to isolate cDNAs from a bovine parathyroid cDNA library by direct selection. One of the novel genes that we identified, SCG2, proved to be identical to the recently published MEN1 gene, which is likely to be a tumour suppressor gene. The SCG2 transcript was 2.9 kb in all tissues with an additional 4.2 kb transcript also being present in the pancreas and thymus. Mutational analysis of SCG2 in 10 unrelated MEN1 families identified one polymorphism and nine different heterozygous mutations (one missense, four non-sense, one insertional and three deletional frameshifts) that segregated with the disease, hence providing an independent confirmation for the identification of the MEN1 gene
Construction of a 1.2-Mb sequence-ready contig of chromosome 11q13 encompassing the multiple endocrine neoplasia type 1 (MEN1) gene
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant familial cancer syndrome characterized by parathyroid, pancreatic, and anterior pituitary tumors. The MEN1 locus has been previously localized to chromosome 11q13, and a 2-Mb gene-rich region flanked by D11S1883 and D11S449 has been defined. We have pursued studies to facilitate identification of the MEN1 gene by narrowing this critical region to a 900-kb interval between the VRF and D11S1783 loci through meiotic mapping. This was achieved by investigating 17 cosmids for microsatellite polymorphisms, which defined two novel polymorphisms at the VRF and A0138 loci, and utilizing these to characterize recombinants in MEN1 families. In addition, we have established a 1200-kb sequence-ready contig consisting of 26 cosmids, eight BACs, and eight PACS that encompass this region. The precise locations for 19 genes and three ESTs within this contig have been determined, and three gene clusters consisting of a centromeric group (VRF, FKBP2, PNG, and PLCB3), a middle group (PYGM, ZFM1, SCG1, SCG2 (which proved to be the MEN1 gene), and PPP2R5B), and a telomeric group (H4B, ANG3, ANG2, ANG1, FON, FAU, NOF, NON, and D11S2196E) were observed. These results represent a valuable transcriptional map of chromosome 11q13 that will help in the search for disease genes in this region
The search for the MEN1 gene. The European Consortium on MEN-1.
The search for the gene whose mutations predispose individuals to multiple endocrine neoplasia type 1 (MEN-1) started in 1988 when the MEN1 locus was assigned to 11q13, close to PYGM. It came to an end with the recent identification of a gene expressed ubiquitously which harbours inactivating mutations associated with MEN-1. During these nine years, the genetic linkage interval had been slowly reduced, and losses of heterozygosity (LOH) in MEN-1 tumours had given strong indications that MEN1 was a tumour suppressor gene. It is ironic that MEN1 was finally found to be located less than 100 kb telomeric to PYGM. From the beginning, this gene was the most tightly linked genetically to MEN-1. In addition, LOH had already shown (in 1990) that it was the most likely centromeric boundary of the MEN1 minimal region. We recently narrowed the critical region to 900 kb through meiotic mapping, and established a 1200-kb sequence-ready contig consisting of cosmids, bacterial artificial chromosomes (BACs) and P1-derived artificial chromosomes (PACs), including three gene clusters (19 genes and 3 expressed sequence tags). Taking LOH results into account, the gene was likely to be present in the 300-kb area telomeric to PYGM that we had covered with BACs. One of the novel genes that we have identified by cDNA selection in this region, SCG2 (Suppressor Candidate Gene 2), proved to be identical to the recently published MEN1 gene. Mutation analysis of SCG2 in 11 unrelated MEN-1 families identified one nucleotide sequence polymorphism and 10 different mutations that segregated with the disease