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1.
Endocr Connect ; 8(3): 289-298, 2019 03 01.
Article in English | MEDLINE | ID: mdl-30763276

ABSTRACT

Multiple endocrine neoplasia type 2 (MEN2) is an autosomal dominant genetic disease caused by RET gene germline mutations that is characterized by medullary thyroid carcinoma (MTC) associated with other endocrine tumors. Several reports have demonstrated that the RET mutation profile may vary according to the geographical area. In this study, we collected clinical and molecular data from 554 patients with surgically confirmed MTC from 176 families with MEN2 in 18 different Brazilian centers to compare the type and prevalence of RET mutations with those from other countries. The most frequent mutations, classified by the number of families affected, occur in codon 634, exon 11 (76 families), followed by codon 918, exon 16 (34 families: 26 with M918T and 8 with M918V) and codon 804, exon 14 (22 families: 15 with V804M and 7 with V804L). When compared with other major published series from Europe, there are several similarities and some differences. While the mutations in codons C618, C620, C630, E768 and S891 present a similar prevalence, some mutations have a lower prevalence in Brazil, and others are found mainly in Brazil (G533C and M918V). These results reflect the singular proportion of European, Amerindian and African ancestries in the Brazilian mosaic genome.

2.
Thyroid ; 27(5): 693-706, 2017 05.
Article in English | MEDLINE | ID: mdl-28276947

ABSTRACT

BACKGROUND: Data on psychological harm in multiple endocrine neoplasia type 2 (MEN2) are scarce. OBJECTIVES: The aim of this study was to assess anxiety, depression, quality of life, and coping in long-standing MEN2 patients. PATIENTS AND METHODS: Patients were 43 adults (age ≥18 years) with clinical and genetic diagnosis of MEN2 and long-term follow-up (10.6 ± 8.2 years; range 1-33 years). This was a cross-sectional study with qualitative and quantitative psychological assessment using semi-directed interviews and HADS, EORTC QLQ C30, and MINI-MAC scales. Adopting clinical criteria from 2015 ATA Guidelines on MEN2, biochemical cure (39%; 16/41), persistence/recurrence (61%; 25/41), and stable chronic disease (22/41) of medullary thyroid carcinoma (MTC) were scored. Pheochromocytoma affected 19 (44%) patients, with previous adrenalectomy in 17 of them. RESULTS: Overall, anxiety (42%; mean score 11 ± 2.9; range 8-18; anxiety is defined as a score ≥8) and depression (26%; mean score 11 ± 3.8; range 8-20; depression is defined as a score ≥8) symptoms were frequent. Patients who transmitted RET mutations to a child had higher scores for weakness-discouragement/anxious preoccupation and lower scores for cognitive, emotional, and physical functioning (p < 0.05). Feelings of guilt were present in 35% of patients with mutation-positive children. Lower mean score values for depression and anxiety and higher scores for role, cognitive, and emotional functioning were noticed in 33 patients who were well-informed about their disease (p < 0.05). Fighting spirit was more frequently found in patients with multiple surgical procedures (p = 0.019) and controlled chronic adrenal insufficiency (p = 0.024). Patients with MEN2-related stress-inducing factors had lower scores for fighting spirit and cognitive functioning and higher scores for insomnia and dyspnea (p < 0.05). Eleven patients required sustained psychotherapeutic treatment. Mean global health status was relatively good in MEN2 cases (68.1 ± 22.3), and the cured group had higher physical functioning (p = 0.021). CONCLUSIONS: Psychological distress is likely chronic in MEN2 patients. This study identified diverse MEN2-related factors (degree of information on disease, mutation-positive children, number of surgeries, comorbidities, stress-inducing factors, and cure) interfering positively or negatively with the results of the psychometrics scales. The active investigation of these factors and the applied psychological assessment protocol are useful to identify MEN2 patients requiring psychological assistance.


Subject(s)
Adaptation, Psychological/physiology , Anxiety/diagnosis , Depression/diagnosis , Multiple Endocrine Neoplasia Type 2a/psychology , Quality of Life/psychology , Adult , Aged , Anxiety/psychology , Cross-Sectional Studies , Depression/psychology , Female , Humans , Male , Middle Aged , Psychiatric Status Rating Scales , Young Adult
6.
Clinics (Sao Paulo) ; 68(7): 1039-56, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23917672

ABSTRACT

Inherited endocrine tumors have been increasingly recognized in clinical practice, although some difficulties still exist in differentiating these conditions from their sporadic endocrine tumor counterparts. Here, we list the 12 main topics that could add helpful information and clues for performing an early differential diagnosis to distinguish between these conditions. The early diagnosis of patients with inherited endocrine tumors may be performed either clinically or by mutation analysis in at-risk individuals. Early detection usually has a large impact in tumor management, allowing preventive clinical or surgical therapy in most cases. Advice for the clinical and surgical management of inherited endocrine tumors is also discussed. In addition, recent clinical and genetic advances for 17 different forms of inherited endocrine tumors are briefly reviewed.


Subject(s)
Multiple Endocrine Neoplasia/diagnosis , Pancreatic Neoplasms/diagnosis , Diagnosis, Differential , Early Detection of Cancer , Female , Germ-Line Mutation , Humans , Male , Multiple Endocrine Neoplasia/genetics , Multiple Endocrine Neoplasia/therapy , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/therapy , Risk Factors
7.
Clinics ; Clinics;68(7): 1039-1056, jul. 2013. tab
Article in English | LILACS | ID: lil-680717

ABSTRACT

Inherited endocrine tumors have been increasingly recognized in clinical practice, although some difficulties still exist in differentiating these conditions from their sporadic endocrine tumor counterparts. Here, we list the 12 main topics that could add helpful information and clues for performing an early differential diagnosis to distinguish between these conditions. The early diagnosis of patients with inherited endocrine tumors may be performed either clinically or by mutation analysis in at-risk individuals. Early detection usually has a large impact in tumor management, allowing preventive clinical or surgical therapy in most cases. Advice for the clinical and surgical management of inherited endocrine tumors is also discussed. In addition, recent clinical and genetic advances for 17 different forms of inherited endocrine tumors are briefly reviewed.


Subject(s)
Female , Humans , Male , Multiple Endocrine Neoplasia/diagnosis , Pancreatic Neoplasms/diagnosis , Diagnosis, Differential , Early Detection of Cancer , Germ-Line Mutation , Multiple Endocrine Neoplasia/genetics , Multiple Endocrine Neoplasia/therapy , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/therapy , Risk Factors
8.
Melanoma Res ; 23(3): 231-6, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23624368

ABSTRACT

Ultraviolet (UV) radiation is a major environmental risk factor to the development of cutaneous melanoma as it induces pyrimidine dimers in DNA. Genes that exert their function by arresting the cell cycle are critical to avoid carcinogenic mutations, allowing the processing of DNA repair systems. This study was carried out to evaluate the role of polymorphisms in cell cycle genes such as TP53, p27, CDKN2A, prohibitin, and GADD153 in melanoma risk as well as their influence on known risk factors in a high UV index region. A hospital-based case-control study was carried out in Brazil to evaluate the contribution of polymorphisms in cell cycle genes toward melanoma risk. The study comprised 202 melanoma patients and 210 controls. The polymorphisms analyzed were TP53 Arg72Pro, p27 Val109Gly, GADD153 Phe10Phe (rs697221), CDKN2A 3'UTR C540G, and prohibitin 3'UTR C1703T. As regards, p27 Val109Gly, both heterozygous and homozygous Gly genotypes were shown to be protective genotypes on calculating both crude and adjusted odds ratios (ORs) for age, sex, and educational level [OR 0.37; 95% confidence interval (CI) 0.16-0.87; P<0.05]. Similarly, the prohibitin TT genotype increased melanoma risk in the crude and adjusted analyses (OR 2.40; 95% CI 1.10-5.26; P<0.05). The p27 Gly protective genotype decreased the risk for melanoma in a stratified analysis of the known risk factors such as hair and eye color, sunburns, pigmented lesions, and European ancestry. The prohibitin TT genotype increased the risk of melanoma by such host factors. Our results showed for the first time that polymorphisms in p27 Val109Gly and in prohibitin 3'UTR C1703T genotypes modulate the risk to melanoma in a high UV index region.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p27/genetics , Melanoma/genetics , Repressor Proteins/genetics , Skin Neoplasms/genetics , Brazil , Case-Control Studies , Female , Humans , Male , Middle Aged , Polymorphism, Genetic , Prohibitins , Risk Factors , Ultraviolet Rays
9.
Clinics (Sao Paulo) ; 67 Suppl 1: 3-6, 2012.
Article in English | MEDLINE | ID: mdl-22584698

ABSTRACT

The finished version of the human genome sequence was completed in 2003, and this event initiated a revolution in medical practice, which is usually referred to as the age of genomic or personalized medicine. Genomic medicine aims to be predictive, personalized, preventive, and also participative (4Ps). It offers a new approach to several pathological conditions, although its impact so far has been more evident in mendelian diseases. This article briefly reviews the potential advantages of this approach, and also some issues that may arise in the attempt to apply the accumulated knowledge from genomic medicine to clinical practice in emerging countries. The advantages of applying genomic medicine into clinical practice are obvious, enabling prediction, prevention, and early diagnosis and treatment of several genetic disorders. However, there are also some issues, such as those related to: (a) the need for approval of a law equivalent to the Genetic Information Nondiscrimination Act, which was approved in 2008 in the USA; (b) the need for private and public funding for genetics and genomics; (c) the need for development of innovative healthcare systems that may substantially cut costs (e.g. costs of periodic medical followup); (d) the need for new graduate and postgraduate curricula in which genomic medicine is emphasized; and (e) the need to adequately inform the population and possible consumers of genetic testing, with reference to the basic aspects of genomic medicine.


Subject(s)
Carcinoma, Medullary/genetics , Delivery of Health Care/economics , Genetic Testing/economics , Multiple Endocrine Neoplasia/genetics , Mutation/genetics , Precision Medicine , Thyroid Neoplasms/genetics , Brazil , Carcinoma, Medullary/diagnosis , Carcinoma, Neuroendocrine , Genetic Privacy/legislation & jurisprudence , Genetic Testing/legislation & jurisprudence , Humans , Insurance, Health/legislation & jurisprudence , Multiple Endocrine Neoplasia/diagnosis , Parathyroid Neoplasms/genetics , Private Sector , Public Sector , Thyroid Neoplasms/diagnosis
10.
Clinics (Sao Paulo) ; 67 Suppl 1: 43-8, 2012.
Article in English | MEDLINE | ID: mdl-22584705

ABSTRACT

We briefly review the characteristics of pituitary tumors associated with multiple endocrine neoplasia type 1. Multiple endocrine neoplasia type 1 is an autosomal-dominant disorder most commonly characterized by tumors of the pituitary, parathyroid, endocrine-gastrointestinal tract, and pancreas. A MEDLINE search for all available publications regarding multiple endocrine neoplasia type 1 and pituitary adenomas was undertaken. The prevalence of pituitary tumors in multiple endocrine neoplasia type 1 may vary from 10% to 60% depending on the studied series, and such tumors may occur as the first clinical manifestation of multiple endocrine neoplasia type 1 in 25% of sporadic and 10% of familial cases. Patients were younger and the time between initial and subsequent multiple endocrine neoplasia type 1 endocrine lesions was significantly longer when pituitary disease was the initial manifestation of multiple endocrine neoplasia type 1. Tumors were larger and more invasive and clinical manifestations related to the size of the pituitary adenoma were significantly more frequent in patients with multiple endocrine neoplasia type 1 than in subjects with non-multiple endocrine neoplasia type 1. Normalization of pituitary hypersecretion was much less frequent in patients with multiple endocrine neoplasia type 1 than in subjects with non-multiple endocrine neoplasia type 1. Pituitary tumors in patients with multiple endocrine neoplasia type 1 syndrome tend to be larger, invasive and more symptomatic, and they tend to occur in younger patients when they are the initial presentation of multiple endocrine neoplasia type 1.


Subject(s)
Adenoma/genetics , Multiple Endocrine Neoplasia Type 1/genetics , Mutation , Pituitary Neoplasms/genetics , Adenoma/pathology , Genes, Neoplasm/genetics , Germ-Line Mutation/genetics , Humans , Multiple Endocrine Neoplasia Type 1/pathology , Pituitary Neoplasms/pathology , Syndrome
11.
Clinics (Sao Paulo) ; 67 Suppl 1: 57-61, 2012.
Article in English | MEDLINE | ID: mdl-22584707

ABSTRACT

Hirschsprung disease is a congenital form of aganglionic megacolon that results from cristopathy. Hirschsprung disease usually occurs as a sporadic disease, although it may be associated with several inherited conditions, such as multiple endocrine neoplasia type 2. The rearranged during transfection (RET) proto-oncogene is the major susceptibility gene for Hirschsprung disease, and germline mutations in RET have been reported in up to 50% of the inherited forms of Hirschsprung disease and in 15-20% of sporadic cases of Hirschsprung disease. The prevalence of Hirschsprung disease in multiple endocrine neoplasia type 2 cases was recently determined to be 7.5% and the cooccurrence of Hirschsprung disease and multiple endocrine neoplasia type 2 has been reported in at least 22 families so far. It was initially thought that Hirschsprung disease could be due to disturbances in apoptosis or due to a tendency of the mutated RET receptor to be retained in the Golgi apparatus. Presently, there is strong evidence favoring the hypothesis that specific inactivating haplotypes play a key role in the fetal development of congenital megacolon/Hirschsprung disease. In the present study, we report the genetic findings in a novel family with multiple endocrine neoplasia type 2: a specific RET haplotype was documented in patients with Hirschsprung disease associated with medullary thyroid carcinoma, but it was absent in patients with only medullary thyroid carcinoma. Despite the limited number of cases, the present data favor the hypothesis that specific haplotypes not linked to RET germline mutations are the genetic causes of Hirschsprung disease.


Subject(s)
Carcinoma, Medullary/genetics , Germ-Line Mutation/genetics , Haplotypes/genetics , Hirschsprung Disease/genetics , Multiple Endocrine Neoplasia Type 2a/genetics , Proto-Oncogene Proteins c-ret/genetics , Thyroid Neoplasms/genetics , Carcinoma, Neuroendocrine , Genotype , Humans , Mutation , Proto-Oncogene Mas
12.
Clinics (Sao Paulo) ; 67 Suppl 1: 99-108, 2012.
Article in English | MEDLINE | ID: mdl-22584713

ABSTRACT

Primary hyperparathyroidism associated with multiple endocrine neoplasia type I (hyperparathyroidism/multiple endocrine neoplasia type 1) differs in many aspects from sporadic hyperparathyroidism, which is the most frequently occurring form of hyperparathyroidism. Bone mineral density has frequently been studied in sporadic hyperparathyroidism but it has very rarely been examined in cases of hyperparathyroidism/multiple endocrine neoplasia type 1. Cortical bone mineral density in hyperparathyroidism/multiple endocrine neoplasia type 1 cases has only recently been examined, and early, severe and frequent bone mineral losses have been documented at this site. Early bone mineral losses are highly prevalent in the trabecular bone of patients with hyperparathyroidism/multiple endocrine neoplasia type 1. In summary, bone mineral disease in multiple endocrine neoplasia type 1 related hyperparathyroidism is an early, frequent and severe disturbance, occurring in both the cortical and trabecular bones. In addition, renal complications secondary to sporadic hyperparathyroidism are often studied, but very little work has been done on this issue in hyperparathyroidism/multiple endocrine neoplasia type 1. It has been recently verified that early, frequent, and severe renal lesions occur in patients with hyperparathyroidism/multiple endocrine neoplasia type 1, which may lead to increased morbidity and mortality. In this article we review the few available studies on bone mineral and renal disturbances in the setting of hyperparathyroidism/multiple endocrine neoplasia type 1. We performed a meta-analysis of the available data on bone mineral and renal disease in cases of multiple endocrine neoplasia type 1-related hyperparathyroidism.


Subject(s)
Bone Density , Hyperparathyroidism, Primary/physiopathology , Kidney Diseases/etiology , Multiple Endocrine Neoplasia Type 1/complications , Bone Demineralization, Pathologic , Bone and Bones/metabolism , Follow-Up Studies , Humans , Hyperparathyroidism, Primary/etiology , Hyperparathyroidism, Primary/surgery , Multiple Endocrine Neoplasia Type 1/genetics , Multiple Endocrine Neoplasia Type 1/surgery , Parathyroid Hormone/blood , Treatment Outcome
13.
Clinics (Sao Paulo) ; 67 Suppl 1: 149-54, 2012.
Article in English | MEDLINE | ID: mdl-22584721

ABSTRACT

We briefly review the surgical approaches to medullary thyroid carcinoma associated with multiple endocrine neoplasia type 2 (medullary thyroid carcinoma/multiple endocrine neoplasia type 2). The recommended surgical approaches are usually based on the age of the affected carrier/patient, tumor staging and the specific rearranged during transfection codon mutation. We have focused mainly on young children with no apparent disease who are carrying a germline rearranged during transfection mutation. Successful management of medullary thyroid carcinoma in these cases depends on early diagnosis and treatment. Total thyroidectomy should be performed before 6 months of age in infants carrying the rearranged during transfection 918 codon mutation, by the age of 3 years in rearranged during transfection 634 mutation carriers, at 5 years of age in carriers with level 3 risk rearranged during transfection mutations, and by the age of 10 years in level 4 risk rearranged during transfection mutations. Patients with thyroid tumor >5 mm detected by ultrasound, and basal calcitonin levels >40 pg/ml, frequently have cervical and upper mediastinal lymph node metastasis. In the latter patients, total thyroidectomy should be complemented by extensive lymph node dissection. Also, we briefly review our data from a large familial medullary thyroid carcinoma genealogy harboring a germline rearranged during transfection Cys620Arg mutation. All 14 screened carriers of the rearranged during transfection Cys620Arg mutation who underwent total thyroidectomy before the age of 12 years presented persistently undetectable serum levels of calcitonin (<2 pg/ml) during the follow-up period of 2-6 years. Although it is recommended that preventive total thyroidectomy in rearranged during transfection codon 620 mutation carriers is performed before the age of 5 years, in this particular family the surgical intervention performed before the age of 12 years led to an apparent biochemical cure.


Subject(s)
Carcinoma, Medullary/surgery , Lymph Node Excision , Multiple Endocrine Neoplasia Type 2a/surgery , Thyroid Neoplasms/surgery , Calcitonin/blood , Carcinoma, Medullary/genetics , Carcinoma, Neuroendocrine , Child , Germ-Line Mutation/genetics , Humans , Multiple Endocrine Neoplasia Type 2a/genetics , Neck , Proto-Oncogene Proteins c-ret/genetics , Thyroid Neoplasms/genetics
14.
Clinics (Sao Paulo) ; 67 Suppl 1: 169-72, 2012.
Article in English | MEDLINE | ID: mdl-22584724

ABSTRACT

The bone mineral density increments in patients with sporadic primary hyperparathyroidism after parathyroidectomy have been studied by several investigators, but few have investigated this topic in primary hyperparathyroidism associated with multiple endocrine neoplasia type 1. Further, as far as we know, only two studies have consistently evaluated bone mineral density values after parathyroidectomy in cases of primary hyperparathyroidism associated with multiple endocrine neoplasia type 1. Here we revised the impact of parathyroidectomy (particularly total parathyroidectomy followed by autologous parathyroid implant into the forearm) on bone mineral density values in patients with primary hyperparathyroidism associated with multiple endocrine neoplasia type 1. Significant increases in bone mineral density in the lumbar spine and femoral neck values were found, although no short-term (15 months) improvement in bone mineral density at the proximal third of the distal radius was observed. Additionally, short-term and medium-term calcium and parathyroid hormone values after parathyroidectomy in patients with primary hyperparathyroidism associated with multiple endocrine neoplasia type 1 are discussed. In most cases, this surgical approach was able to restore normal calcium/parathyroid hormone levels and ultimately lead to discontinuation of calcium and calcitriol supplementation.


Subject(s)
Bone Density , Hyperparathyroidism, Primary/surgery , Multiple Endocrine Neoplasia Type 1/surgery , Calcium/blood , Follow-Up Studies , Humans , Hyperparathyroidism, Primary/physiopathology , Multiple Endocrine Neoplasia Type 1/physiopathology , Parathyroid Hormone/blood , Parathyroidectomy/methods , Postoperative Period
15.
Clinics (Sao Paulo) ; 67(3): 265-72, 2012.
Article in English | MEDLINE | ID: mdl-22473409

ABSTRACT

OBJECTIVE: To investigate a possible direct, growth hormone-releasing, hormone-independent action of a growth hormone secretagogue, GHRP-2, in pituitary somatotroph cells in the presence of inactive growth hormone-releasing hormone receptors. MATERIALS AND METHODS: The responses of serum growth hormone to acutely injected growth hormone-releasing P-2 in lit/lit mice, which represent a model of GH deficiency arising from mutated growth hormone-releasing hormone-receptors, were compared to those observed in the heterozygous (lit/+) littermates and wild-type (+/+) C57BL/6J mice. RESULTS: After the administration of 10 mcg of growth hormone-releasing P-2 to lit/lit mice, a growth hormone release of 9.3±1.5 ng/ml was observed compared with 1.04±1.15 ng/ml in controls (p<0.001). In comparison, an intermediate growth hormone release of 34.5±9.7 ng/ml and a higher growth hormone release of 163±46 ng/ml were induced in the lit/+ mice and wild-type mice, respectively. Thus, GHRP-2 stimulated growth hormone in the lit/lit mice, and the release of growth hormone in vivo may be only partially dependent on growth hormone-releasing hormone. Additionally, the plasma leptin and ghrelin levels were evaluated in the lit/lit mice under basal and stimulated conditions. CONCLUSIONS: Here, we have demonstrated that lit/lit mice, which harbor a germline mutation in the Growth hormone-releasing hormone gene, maintain a limited but statistically significant growth hormone elevation after exogenous stimulation with GHRP-2. The present data probably reflect a direct, growth hormone-independent effect on Growth hormone S (ghrelin) stimulation in the remaining pituitary somatotrophs of little mice that is mediated by growth hormone S-R 1a.


Subject(s)
Growth Hormone/metabolism , Oligopeptides/pharmacology , Receptors, Neuropeptide/genetics , Receptors, Pituitary Hormone-Regulating Hormone/genetics , Analysis of Variance , Animals , Disease Models, Animal , Female , Ghrelin/blood , Growth Hormone/deficiency , Heterozygote , Leptin/blood , Male , Mice , Mice, Inbred C57BL , Mice, Mutant Strains , Oligopeptides/administration & dosage , Random Allocation
16.
Pituitary ; 15(3): 342-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-21744088

ABSTRACT

A 39-year-old woman with autosomal dominant polycystic kidney disease (ADPKD) presented with acromegaly and a pituitary macroadenoma. There was a family history of this renal disorder. She had undergone surgery for pituitary adenoma 6 years prior. Physical examination disclosed bitemporal hemianopsia and elevation of both basal growth hormone (GH) 106 ng/mL (normal 0-5) and insulin-like growth factor (IGF-1) 811 ng/mL (normal 48-255) blood levels. A magnetic resonance imaging scan disclosed a 3.0 cm sellar and suprasellar mass with both optic chiasm compression and left cavernous sinus invasion. Pathologic, cytogenetic, molecular and in silico analysis was undertaken. Histologic, immunohistochemical and ultrastructural studies of the lesion disclosed a sparsely granulated somatotroph adenoma. Standard chromosome analysis on the blood sample showed no abnormality. Sequence analysis of the coding regions of PKD1 and PKD2 employing DNA from both peripheral leukocytes and the tumor revealed the most common PKD1 mutation, 5014_5015delAG. Analysis of the entire SSTR5 gene disclosed the variant c.142C>A (p.L48M, rs4988483) in the heterozygous state in both blood and tumor, while no pathogenic mutations were noted in the MEN1, AIP, p27Kip1 and SSTR2 genes. To our knowledge, this is the fourth reported case of a GH-producing pituitary adenoma associated with ADPKD, but the first subjected to extensive morphological, ultrastructural, cytogenetic and molecular studies. The physical proximity of the PKD1 and SSTR5 genes on chromosome 16 suggests a causal relationship between ADPKD and somatotroph adenoma.


Subject(s)
Acromegaly/complications , Acromegaly/genetics , Growth Hormone-Secreting Pituitary Adenoma/complications , Growth Hormone-Secreting Pituitary Adenoma/genetics , Pituitary Neoplasms/complications , Polycystic Kidney, Autosomal Dominant/complications , Polycystic Kidney, Autosomal Dominant/genetics , Receptors, Somatostatin/genetics , TRPP Cation Channels/genetics , Acromegaly/pathology , Adenoma/complications , Adenoma/genetics , Adult , Base Sequence , Female , Humans , Pituitary Gland/pathology , Pituitary Neoplasms/genetics , Pituitary Neoplasms/pathology , Polymorphism, Genetic
17.
Clinics ; Clinics;67(3): 265-272, 2012. graf, tab
Article in English | LILACS | ID: lil-623102

ABSTRACT

OBJECTIVE: To investigate a possible direct, growth hormone-releasing, hormone-independent action of a growth hormone secretagogue, GHRP-2, in pituitary somatotroph cells in the presence of inactive growth hormonereleasing hormone receptors. MATERIALS AND METHODS: The responses of serum growth hormone to acutely injected growth hormone-releasing P-2 in lit/litmice, which represent a model of GH deficiency arising frommutated growth hormone-releasing hormonereceptors, were compared to those observed in the heterozygous (lit/+) littermates and wild-type (+/+) C57BL/6J mice. RESULTS: After the administration of 10 mcg of growth hormone-releasing P-2 to lit/lit mice, a growth hormone release of 9.3±1.5 ng/ml was observed compared with 1.04±1.15 ng/ml in controls (p<0.001). In comparison, an intermediate growth hormone release of 34.5±9.7 ng/ml and a higher growth hormone release of 163±46 ng/ml were induced in the lit/+ mice and wild-type mice, respectively. Thus, GHRP-2 stimulated growth hormone in the lit/lit mice, and the release of growth hormone in vivo may be only partially dependent on growth hormone-releasing hormone. Additionally, the plasma leptin and ghrelin levels were evaluated in the lit/lit mice under basal and stimulated conditions. CONCLUSIONS: Here, we have demonstrated that lit/lit mice, which harbor a germline mutation in the Growth hormone-releasing hormone gene, maintain a limited but statistically significant growth hormone elevation after exogenous stimulation with GHRP-2. The present data probably reflect a direct, growth hormone-independent effect on Growth hormone S (ghrelin) stimulation in the remaining pituitary somatotrophs of little mice that is mediated by growth hormone S-R 1a.


Subject(s)
Animals , Female , Male , Mice , Growth Hormone/metabolism , Oligopeptides/pharmacology , Receptors, Neuropeptide/genetics , Receptors, Pituitary Hormone-Regulating Hormone/genetics , Analysis of Variance , Disease Models, Animal , Ghrelin/blood , Growth Hormone/deficiency , Heterozygote , Leptin/blood , Mice, Mutant Strains , Oligopeptides/administration & dosage , Random Allocation
18.
Clinics ; Clinics;67(supl.1): 3-6, 2012.
Article in English | LILACS | ID: lil-623123

ABSTRACT

The finished version of the human genome sequence was completed in 2003, and this event initiated a revolution in medical practice, which is usually referred to as the age of genomic or personalized medicine. Genomic medicine aims to be predictive, personalized, preventive, and also participative (4Ps). It offers a new approach to several pathological conditions, although its impact so far has been more evident in mendelian diseases. This article briefly reviews the potential advantages of this approach, and also some issues that may arise in the attempt to apply the accumulated knowledge from genomic medicine to clinical practice in emerging countries. The advantages of applying genomic medicine into clinical practice are obvious, enabling prediction, prevention, and early diagnosis and treatment of several genetic disorders. However, there are also some issues, such as those related to: (a) the need for approval of a law equivalent to the Genetic Information Nondiscrimination Act, which was approved in 2008 in the USA; (b) the need for private and public funding for genetics and genomics; (c) the need for development of innovative healthcare systems that may substantially cut costs (e.g. costs of periodic medical followup); (d) the need for new graduate and postgraduate curricula in which genomic medicine is emphasized; and (e) the need to adequately inform the population and possible consumers of genetic testing, with reference to the basic aspects of genomic medicine.


Subject(s)
Humans , Carcinoma, Medullary/genetics , Delivery of Health Care/economics , Genetic Testing/economics , Multiple Endocrine Neoplasia/genetics , Mutation/genetics , Precision Medicine , Thyroid Neoplasms/genetics , Brazil , Carcinoma, Medullary/diagnosis , Genetic Privacy/legislation & jurisprudence , Genetic Testing/legislation & jurisprudence , Insurance, Health/legislation & jurisprudence , Multiple Endocrine Neoplasia/diagnosis , Private Sector , Public Sector , Parathyroid Neoplasms/genetics , Thyroid Neoplasms/diagnosis
19.
Clinics ; Clinics;67(supl.1): 43-48, 2012.
Article in English | LILACS | ID: lil-623130

ABSTRACT

We briefly review the characteristics of pituitary tumors associated with multiple endocrine neoplasia type 1. Multiple endocrine neoplasia type 1 is an autosomal-dominant disorder most commonly characterized by tumors of the pituitary, parathyroid, endocrine-gastrointestinal tract, and pancreas. A MEDLINE search for all available publications regarding multiple endocrine neoplasia type 1 and pituitary adenomas was undertaken. The prevalence of pituitary tumors in multiple endocrine neoplasia type 1 may vary from 10% to 60% depending on the studied series, and such tumors may occur as the first clinical manifestation of multiple endocrine neoplasia type 1 in 25% of sporadic and 10% of familial cases. Patients were younger and the time between initial and subsequent multiple endocrine neoplasia type 1 endocrine lesions was significantly longer when pituitary disease was the initial manifestation of multiple endocrine neoplasia type 1. Tumors were larger and more invasive and clinical manifestations related to the size of the pituitary adenoma were significantly more frequent in patients with multiple endocrine neoplasia type 1 than in subjects with non-multiple endocrine neoplasia type 1. Normalization of pituitary hypersecretion was much less frequent in patients with multiple endocrine neoplasia type 1 than in subjects with non-multiple endocrine neoplasia type 1. Pituitary tumors in patients with multiple endocrine neoplasia type 1 syndrome tend to be larger, invasive and more symptomatic, and they tend to occur in younger patients when they are the initial presentation of multiple endocrine neoplasia type 1.


Subject(s)
Humans , Adenoma/genetics , Mutation , Multiple Endocrine Neoplasia Type 1/genetics , Pituitary Neoplasms/genetics , Adenoma/pathology , Genes, Neoplasm/genetics , Germ-Line Mutation/genetics , Multiple Endocrine Neoplasia Type 1/pathology , Pituitary Neoplasms/pathology , Syndrome
20.
Clinics ; Clinics;67(supl.1): 57-61, 2012. ilus, tab
Article in English | LILACS | ID: lil-623132

ABSTRACT

Hirschsprung disease is a congenital form of aganglionic megacolon that results from cristopathy. Hirschsprung disease usually occurs as a sporadic disease, although it may be associated with several inherited conditions, such as multiple endocrine neoplasia type 2. The rearranged during transfection (RET) proto-oncogene is the major susceptibility gene for Hirschsprung disease, and germline mutations in RET have been reported in up to 50% of the inherited forms of Hirschsprung disease and in 15-20% of sporadic cases of Hirschsprung disease. The prevalence of Hirschsprung disease in multiple endocrine neoplasia type 2 cases was recently determined to be 7.5% and the cooccurrence of Hirschsprung disease and multiple endocrine neoplasia type 2 has been reported in at least 22 families so far. It was initially thought that Hirschsprung disease could be due to disturbances in apoptosis or due to a tendency of the mutated RET receptor to be retained in the Golgi apparatus. Presently, there is strong evidence favoring the hypothesis that specific inactivating haplotypes play a key role in the fetal development of congenital megacolon/Hirschsprung disease. In the present study, we report the genetic findings in a novel family with multiple endocrine neoplasia type 2: a specific RET haplotype was documented in patients with Hirschsprung disease associated with medullary thyroid carcinoma, but it was absent in patients with only medullary thyroid carcinoma. Despite the limited number of cases, the present data favor the hypothesis that specific haplotypes not linked to RET germline mutations are the genetic causes of Hirschsprung disease.


Subject(s)
Humans , Carcinoma, Medullary/genetics , Germ-Line Mutation/genetics , Haplotypes/genetics , Hirschsprung Disease/genetics , /genetics , Proto-Oncogene Proteins c-ret/genetics , Thyroid Neoplasms/genetics , Genotype , Mutation
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