PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Multiple Endocrine Neoplasia”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

Multiple leiomyomas of the esophagus, lung, and uterus in multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant hereditary disorder characterized by multiple parathyroid, pancreatic, duodenal, and pituitary neuroendocrine tumors. Nonendocrine mesenchymal tumors, such as lipomas, collagenomas, and angiofibromas have also been reported. MEN1-associated neuroendocrine and some mesenchymal tumors have documented MEN1 gene alterations on chromosome 11q13. To test whether the MEN1 gene is involved in the pathogenesis of multiple smooth muscle tumors, we examined the 11q13 loss of heterozygosity (LOH) and clonality patterns in 15 leiomyomata of the esophagus, lung, and uterus from five patients with MEN1. Forty sporadic uterine leiomyomata were also studied for 11q13 LOH. LOH analysis was performed using four polymorphic DNA markers at the MEN1 gene locus; D11S480, PYGM, D11S449, and INT-2. 11q13 LOH was detected in 10 of 12 (83%) MEN1-associated esophageal and uterine smooth muscle tumors. In contrast, LOH at the MEN1 gene locus was demonstrated only in 2 of 40 (5%) sporadic uterine tumors. LOH at 11q13 was not documented in three lung smooth muscle tumors from a single patient with MEN1. Ten tumors from two female patients were additionally assessed for clonality by X-chromosome inactivation analysis. The results demonstrated different clonality patterns in multiple tumors in the same organ in each individual patient. The data indicate that leiomyomata of the esophagus and uterus in MEN1 patients arise as independent clones, develop through MEN1 gene alterations, and are an integral part of MEN1. However, the MEN1 gene is not a significant contributor to the tumorigenesis of sporadic uterine leiomyomata.

Adult↗

Recent advances in multiple endocrine neoplasia syndromes.

The MEN syndrome are autosomal-dominant disorders of endocrine tissues, characterized by tumor development and in many instances, hormonal hypersecretory states. The genetic lesion in MEN I appears to involve a tumor suppressor locus on the long arm of chromosomes 11 but the identity of the affected gene and its role in contributing to dysregulation of endocrine cell function remain unknown. The lesion in MEN II has been localized to the RET protooncogene locus in the pericentromeric region of chromosome 10. This putative single transmembrane-domain, tyrosine kinase-linked receptor is selectively mutated to produce a constitutively activated protein and presumably an undampened growth-promoting signal to the target cell. Additional studies focused on these genes and their products should facilitate the screening and treatment of patients affected with these disorders and, potentially, provide more information about the role that these genes play in the normal growth and development of endocrine tissues. Such information should prove valuable in deciphering the pathogenetic mechanisms underlying the development of the more common sporadic endocrine tumors.

Diagnosis, Differential↗

Sporadic primary hyperparathyroidism in the setting of multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant disease characterized by neoplasia involving the parathyroid glands, the endocrine pancreas, the duodenum, and the anterior pituitary. The most commonly involved gland is the parathyroid gland, which has been found to be abnormal in 90% to 95% of all patients with MEN 1. The disease process is invariably multiglandular and histologically described as either hyperplasia or multiple adenoma, although the histological distinction between the 2 entities remains difficult and controversial. The prevalence of MEN 1 is approximately 0.002 in 100, whereas the prevalence of sporadic primary hyperparathyroidism due to a solitary adenoma is estimated to be as high as 1 in 100.(2.3) We report herein the first case of sporadic primary hyperparathyroidism in the setting of MEN 1 based on clinical, biochemical, pathological, and genetic studies.

Adenoma, Oxyphilic↗

Multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia-1 (MEN-1) is an autosomal dominant inherited syndrome that occurs due to inactivating mutations of the MEN1 gene locus, coding for a tumor-suppressor protein, menin. The components of MEN-1 are hyperparathyroidism due to multiple parathyroid adenomas, pancreatic neuroendocrine tumors, and pituitary adenomas, in addition to some less common neoplastic manifestations. Care of people with MEN-1 requires knowledge of the problems that may arise, and the best approaches to detect and care for the manifestations of this incurable, but manageable, disease.

Adenoma↗

Malignant thymic carcinoid is not prevented by transcervical thymectomy in multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant tumour syndrome. It is characterized by primary hyperparathyroidism, pituitary neoplasia and foregut lineage neuroendocrine neoplasia. Malignant thymic carcinoid tumours are an uncommon but important manifestation of MEN 1. Transcervical thymectomy is often advocated as prophylaxis against thymic carcinoids, although there is a paucity of evidence to support the efficacy of this procedure. This is the first report of a malignant thymic carcinoid occurring in an MEN 1 patient following prior parathyroidectomy and transcervical thymectomy. It is concluded that transcervical thymectomy does not reliably provide prophylaxis against thymic carcinoid.

Adolescent↗

Broad tumor spectrum in a mouse model of multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN1) is an inherited cancer predisposition syndrome typified by development of tumors in parathyroid, pituitary and endocrine pancreas, as well as less common sites including both endocrine and nonendocrine organs. Deletion or mutation of the tumor suppressor gene MEN1 on chromosome 11 has been identified in many cases of MEN1 as well as in sporadic tumors. The molecular biology of menin, the protein encoded by MEN1, remains poorly understood. Here we describe a mouse model of MEN1 in which tumors were seen in pancreatic islets, pituitary, thyroid and parathyroid, adrenal glands, testes and ovaries. The observed tumor spectrum therefore includes types commonly seen in MEN1 patients and additional types. Pancreatic pathology was most common, evident in over 80% of animals, while other tumor types developed with lower frequency and generally later onset. Tumors of multiple endocrine organs were observed frequently, but progression to carcinoma and metastasis were not evident. Tumors in all sites showed loss of heterozygosity at the Men1 locus, though the frequency in testicular tumors was only 36%, indicating that a different molecular mechanism of tumorigenesis occurs in those Leydig tumors that do not show loss of the normal Men1 allele. Menin expression was below the level of detection in ovary, thyroid and testis, but loss of nuclear menin immunoreactivity was observed uniformly in all pancreatic islet adenomas and in some hyperplastic islet cells, suggesting that complete loss of Men1 is a critical point in islet tumor progression in this model.

Adenoma↗

Deletion mapping on the distal third region of chromosome 1p in multiple endocrine neoplasia type IIA.

Multiple endocrine neoplasia type IIA (MEN IIA) syndrome is an autosomal-dominant endocrine disorder that consists of medullary thyroid carcinoma (MTC), pheochromocytoma, and parathyroid hyperplasia. The susceptibility gene to this disorder has been mapped to chromosome 10. However, molecular studies of tumor cells from patients with familial and sporadic MTC and/or pheochromocytoma have shown a high frequency (50%) of abnormalities on chromosome 1p. In the present study, we examined MTC or pheochromocytoma tumor specimens from eight patients (familial and nonfamilial cases) to investigate gene losses on chromosomes 1 and 10 as potential mechanisms for the tumors' development. The patients studies had homozygous genotypes in their leukocyte DNAs for the chromosome 10 marker used in this study, and the patients were, therefore, uninformative. However, the patients were informative for the chromosome 1 markers and five of the patients' tumor-cell DNAs (63%) had allelic deletions at one or multiple loci on chromosome 1p, and one tumor DNA had evidence of possible gene rearrangement; in all six cases, the abnormalities involved the distal third of chromosome 1p. Furthermore, we determined that the common break point for the 1p deletions was at 1p32. These results suggest that a tumor suppressor gene in this defined region is involved in the development/progression of MTC and pheochromocytoma by being either lost or inactivated.

Adolescent↗

Clinical and molecular diagnosis of multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN1) is a classic hereditary tumor syndrome characterized by a genetic predisposition to develop a variety of neuroendocrine neoplasias and hormone excess syndromes. The disease is caused by inactivating mutations of the MEN1 tumor suppressor gene, detectable in >95% of MEN1 families. The distinction of MEN1-associated tumors from sporadic neuroendocrine neoplasias is clinically important for providing optimal surgical and medical therapy, appropriate clinical follow-up, and counsel for affected patients and their families. Since MEN1 gene analysis became available in 1997, new diagnostic approaches have evolved in clinical management, to be reviewed in this article. Genetic screening of MEN1 families will allow definition of individual disease risk at a preclinical stage, thus helping to allocate medical resources and treatment as individually needed. These new diagnostic approaches are expected to reduce MEN1-associated morbidity and mortality, health care expenses, and psychological disease burden.

DNA Mutational Analysis↗

A germline mutation in a Thai family with familial multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1, caused by the mutation in the MEN1 gene, is an autosomal dominant disorder with over 95% penetrance characterized by hyperparathyroidism, pancreatic endocrine tumor and pituitary tumor. The authors performed a molecular analysis to identify a mutation in a Thai man with MEN1. He was found to be heterozygous for IVS6 + 1G to A. Two of his three children were also found to carry this mutation. The newly available genetic test for patients with MEN1 in Thailand makes it possible to accurately DNA-based diagnose clinically suspected individuals and their presymptomatic members, which has important therapeutic impacts on them.

Adult↗

Familial medullary thyroid carcinoma and multiple endocrine neoplasia type 2B map to the same region of chromosome 10 as multiple endocrine neoplasia type 2A.

Medullary thyroid carcinoma (MTC) occurs as a component of three well-described autosomal dominant familial cancer syndromes. Multiple endocrine neoplasia type 2A (MEN 2A) is characterized by MTC, pheochromocytomas, and parathyroid hyperplasia. Patients with the rarer multiple endocrine neoplasia type 2B (MEN 2B) syndrome develop MTC and pheochromocytomas, as well as mucosal neuromas, ganglioneuromatosis of the gastrointestinal tract, and a characteristic "marfanoid" habitus. Finally, MTC is transmitted in an autosomal dominant pattern in some families without associated pheochromocytomas or parathyroid hyperplasia (familial medullary thyroid carcinoma, MTC1(2). Sixty-one members of two well-characterized kindreds segregating MTC1 and 34 [corrected] members of six families segregating MEN2B were genotyped using a panel of RFLP probes from the pericentromeric region of chromosome 10 near a locus for MEN 2A. Statistically significant linkage was observed between the chromosome 10 centromere-specific marker D10Z1 and MTC1 (maximum pairwise lod score 5.88 with 0% recombination) and D10Z1 and MEN2B (maximum pairwise lod score 3.58 with 0% recombination). A maximum multipoint lod score of 4.08 was obtained for MEN2B at the position of D10Z1. In addition, 92 members of a previously unreported large MEN2A kindred were genotyped, and linkage to the pericentromeric region of chromosome 10 is reported (maximum pairwise lod score of 11.33 with 0% recombination between MEN2A and RBP3). These results demonstrate that both a locus for familial MTC and a locus for MEN 2B map to the pericentromeric region of chromosome 10, in the same region as a locus for MEN 2A. The finding that each of these three clinically distinct familial cancer syndromes maps to the same chromosomal region suggests that all are allelic mutations at the same locus or represent a cluster of genes involved in the regulation of neuroendocrine tissue development.

Adrenal Gland Neoplasms↗

Molecular and genetic mechanisms of tumorigenesis in multiple endocrine neoplasia type-1.

Multiple endocrine neoplasia type 1 (MEN1) is a rare but informative syndrome for endocrine tumorigenesis. Since its isolation, several groups have begun to determine the role of menin, the protein product of MEN1, in sporadic endocrine tumors as well as tumors of the MEN1 syndrome. Mutations of menin have been reported in more than 400 families and tumors, most of which are truncating mutations, thus supporting the function of menin as a tumor suppressor. The exact function of menin is unknown, but overexpression of menin inhibits proliferation of Ras-transformed NIH3T3 cells. Since menin interacts with proteins from both the TGF beta and AP-1 signaling pathways, perhaps its tumor suppressor function is related to these key cell growth pathways. In this review we will discuss the various clinical manifestations of MEN1 syndrome, potential mechanisms of MEN1 tumorigenesis, and mutations associated with MEN and sporadic endocrine tumors.

Amino Acid Sequence↗

Menin interacting proteins as clues toward the understanding of multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN1) is a familial cancer syndrome characterized mostly by tumors of the parathyroids, pancreas and anterior pituitary. The gene responsible, MEN1, encodes Menin, a 610 aminoacid nuclear protein with no sequence homology to other proteins. Although a mouse knock-out model is available, the function of Menin is still elusive. Proteins of known function are shown to interact with Menin: JunD, nuclear factor-KappaB, Smad3, Pem, Nm23H1, glial fibrillary acidic protein, Vimentin, and probably P53. Their partnership with Menin may correspond to a regulation of their activity, but their relevance to the various traits of MEN1 pathogenicity is not established. This raises fundamental issues on the regulation pathways implicated in this complex endocrine disease.

Animals↗

Genetic and clinical characteristics of multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN 1) is an inherited disorder of autosomal-dominant type encompassing tumors of the parathyroid glands, anterior pituitary and endocrine pancreas. The genetic defect responsible for MEN 1 maps to the long arm of chromosome 11 (11q13). Constitutional heterozygosity for the MEN 1 region is lost in proliferating pancreatic endocrine and parathyroid tissue, which suggests that the MEN 1 gene belongs to the group of tumor suppressor genes (antioncogenes). Genetic screening by linkage analysis using RFLP markers allows selection of gene carriers with high degree of accuracy and makes it possible to concentrate the laborious biochemical screening efforts to family members at risk of developing the MEN 1 syndrome. Biochemical screening of the MEN 1 lesions in young asymptomatic individuals decreases the age at diagnosis with many years (decades) and therapeutic intervention can be instituted early. Although it still remains to be established whether early intervention will have an impact on mortality, our long-term experience with 20 MEN 1 kindreds suggests a reduced morbidity as a result of thorough biochemical screening.

Adult↗

A whole MEN1 gene deletion flanked by Alu repeats in a family with multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 is an autosomal dominant cancer syndrome characterized by pituitary, parathyroid and enteropancreatic endocrine tumors, which is caused by germline mutations of the tumor suppressor gene MEN1. In the case reported here, the patient had family with this disease whose germline MEN1 mutation was undetectable by conventional sequencing analysis. Further investigations involving polymorphism analyses, gene dose assay and nucleotide sequencing identified a large germline deletion of approximately 29 kilobase pairs spanning the whole MEN1 gene. The deletion was flanked by Alu repetitive sequences, suggesting unequal homologous recombination as the deletion mechanism. The polymorphism linkage data suggested that an asymptomatic son of the proband did not carry the family mutation. More direct evidence was obtained by gene dose assay and deletion-specific polymerase chain reaction, which demonstrated the normal MEN1 gene dosage and the absence of the deletion breakpoints in this asymptomatic subject and thus definitely excluded the possibility of disease predisposition.

Alu Elements↗

Hypermutability in a Drosophila model for multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type I (MEN1) is an autosomal dominant cancer predisposition syndrome, the gene for which encodes a nuclear protein, menin. The biochemical function of this protein has not been completely elucidated, but several studies have shown a role in transcriptional modulation through recruitment of histone deacetylase. The mechanism by which MEN1 mutations cause tumorigenesis is unknown. The Drosophila homolog of MEN1, Mnn1, encodes a protein 50% identical to human menin. In order to further elucidate the function of MEN1, we generated a null allele of this gene in Drosophila and showed that homozygous inactivation results in morphologically normal flies that are hypersensitive to ionizing radiation and two DNA cross-linking agents, nitrogen mustard and cisplatinum. The spectrum of agents to which mutant flies are sensitive and analysis of the molecular mechanisms of this sensitivity suggest a defect in nucleotide excision repair. Drosophila Mnn1 mutants have an elevated rate of both sporadic and DNA damage-induced mutations. In a genetic background heterozygous for lats, a Drosophila and vertebrate tumor suppressor gene, homozygous inactivation of Mnn1 enhanced somatic mutation of the second allele of lats and formation of multiple primary tumors. Our data indicate that Mnn1 is a novel member of the class of autosomal dominant cancer genes that function in maintenance of genomic integrity, similar to the BRCA and HNPCC genes.

Animals↗

Genetic and clinical analysis in 10 Spanish patients with multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN 1) is characterised by the combination of tumours of the parathyroid, endocrine pancreas and anterior pituitary glands. In 1988 the MEN 1 gene was mapped to chromosome 11q13 and it was cloned in 1997. This gene contains 10 exons and extends across 9 Kb of genomic DNA; it encodes for a product of 610 amino acid named menin whose function is unknown. We have studied 10 unrelated MEN 1 kindreds by a complete sequencing analysis of the entire gene; mutations were identified in nine of them: five deletions, one insertion, two nonsense mutation and a complex alteration consisting of a deletion and an insertion that can be explained by a hairpin loop model. Two of the mutations have been previously described; the other seven were novel, and they were scattered throughout the coding sequence of the gene. As in previous series, no correlation was found between phenotype and genotype.

Base Sequence↗

Gastrointestinal manifestations of multiple endocrine neoplasia, type IIB.

Multiple endocrine neoplasia, type IIB (MEN 2b), is comprised of medullary carcinoma of the thyroid, pheochromocytoma, diffuse ganglioneuromatosis of the gastrointestinal tract, and skeletal abnormalities. Alimentary tract manifestations, especially enlargement of the lips and tongue by proliferative neural tissue, are often the earliest clues to the presence of the syndrome. A patient is presented here who illustrates the chronicity and diversity of symptoms characteristic of MEN 2b. It is important to recognize the typical oral manifestations of this syndrome so that the thyroid gland can be evaluated before the development of disseminated medullary carcinoma.

Adult↗

Prolactinoma presenting in identical twins with multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type one (MEN 1) is characterized by tumours of the parathyroid glands, pancreatic islet cells and the anterior pituitary and follows an autosomal dominant pattern of inheritance. We report identical twins born to a family known to have the MEN 1 syndrome. The twins were identical until puberty. The first twin underwent puberty normally; the second, however, suffered an early pubertal arrest and was subsequently found to have a prolactinoma. Both were also subsequently shown to have primary hyperparathyroidism. Genetic studies have since confirmed the twins identical for the affected haplotype and show that this is inherited from the father who also has MEN 1. The gene for MEN 1 has now been localized to the long arm of chromosome 11. The current hypothesis is that expression of the syndrome involves two separate genetic mutations. The first mutation is inherited and thus present in all cells but the tumour manifests itself in the endocrine tissue only after a second mutation that represents elimination of the normal allele. In the case described the twins are proven genetically identical. The marked phenotypic difference between the two must, by inference, represent a second somatic mutation and is further supportive evidence of the two-mutation model of tumour expression.

Adolescent↗