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1.
EBioMedicine ; 43: 537-552, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30975543

RESUMO

BACKGROUND: Acromegaly is produced by excess growth hormone secreted by a pituitary adenoma of somatotroph cells (ACRO). First-line therapy, surgery and adjuvant therapy with somatostatin analogs, fails in 25% of patients. There is no predictive factor of resistance to therapy. New therapies are investigated using few dispersed tumor cells in acute primary cultures in standard conditions where the cells do not grow, or using rat pituitary cell lines that do not maintain the full somatotroph phenotype. The RET/PIT1/p14ARF/p53 pathway regulates apoptosis in normal pituitary somatotrophs whereas the RET/GDNF pathway regulates survival, controlling PIT1 levels and blocking p14ARF (ARF) and p53 expression. METHODS: We investigated these two RET pathways in a prospective series of 32 ACRO and 63 non-functioning pituitary adenomas (NFPA), studying quantitative RNA and protein gene expression for molecular-clinical correlations and how the RET pathway might be implicated in therapeutic success. Clinical data was collected during post-surgical follow-up. We also established new'humanized' pituitary cultures, allowing 20 repeated passages and maintaining the pituitary secretory phenotype, and tested five multikinase inhibitors (TKI: Vandetanib, Lenvatinib, Sunitinib, Cabozantinib and Sorafenib) potentially able to act on the GDNF-induced RET dimerization/survival pathway. Antibody arrays investigated intracellular molecular pathways. FINDINGS: In ACRO, there was specific enrichment of all genes in both RET pathways, especially GDNF. ARF and GFRA4 gene expression were found to be opposing predictors of response to first-line therapy. ARF cut-off levels, calculated categorizing by GNAS mutation, were predictive of good response (above) or resistance (below) to therapy months later. Sorafenib, through AMPK, blocked the GDNF/AKT survival action without altering the RET apoptotic pathway. INTERPRETATION: Tumor ARF mRNA expression measured at the time of the surgery is a prognosis factor in acromegaly. The RET inhibitor, Sorafenib, is proposed as a potential treatment for resistant ACRO. FUND: This project was supported by national grants from Agencia Estatal de Investigación (AEI) and Instituto Investigación Carlos III, with participation of European FEDER funds, to IB (PI150056) and CVA (BFU2016-76973-R). It was also supported initially by a grant from the Investigator Initiated Research (IIR) Program (WI177773) and by a non-restricted Research Grant from Pfizer Foundation to IB. Some of the pituitary acromegaly samples were collected in the framework of the Spanish National Registry of Acromegaly (REMAH), partially supported by an unrestricted grant from Novartis to the Spanish Endocrine Association (SEEN). CVA is also supported from a grant of Medical Research Council UK MR/M018539/1.


Assuntos
Acromegalia/diagnóstico , Acromegalia/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Fator de Transcrição Pit-1/metabolismo , Proteína Supressora de Tumor p14ARF/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Acromegalia/genética , Acromegalia/terapia , Animais , Apoptose/genética , Biomarcadores , Terapia Combinada , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Humanos , Imuno-Histoquímica , Modelos Biológicos , Mutação , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-ret/genética , Ratos , Transdução de Sinais , Fator de Transcrição Pit-1/genética , Resultado do Tratamento , Proteína Supressora de Tumor p14ARF/genética , Proteína Supressora de Tumor p53/genética
2.
Nat Rev Dis Primers ; 5(1): 20, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30899019

RESUMO

Acromegaly is characterized by increased release of growth hormone and, consequently, insulin-like growth factor I (IGF1), most often by a pituitary adenoma. Prolonged exposure to excess hormone leads to progressive somatic disfigurement and a wide range of systemic manifestations that are associated with increased mortality. Although considered a rare disease, recent studies have reported an increased incidence of acromegaly owing to better disease awareness, improved diagnostic tools and perhaps a real increase in prevalence. Acromegaly treatment approaches, which include surgery, radiotherapy and medical therapy, have changed considerably over time owing to improved surgical procedures, development of new radiotherapy techniques and availability of new medical therapies. The optimal use of these treatments will reduce mortality in patients with acromegaly to levels in the general population. Medical therapy is currently an important treatment option and can even be the first-line treatment in patients with acromegaly who will not benefit from or are not suitable for first-line neurosurgical treatment. Pharmacological treatments include somatostatin receptor ligands (such as octreotide, lanreotide and pasireotide), dopamine agonists and the growth hormone receptor antagonist pegvisomant. In this Primer, we review the main aspects of acromegaly, including scientific advances that underlie expanding knowledge of disease pathogenesis, improvements in disease management and new medical therapies that are available and in development to improve disease control.


Assuntos
Acromegalia/diagnóstico , Fator de Crescimento Insulin-Like I/metabolismo , Acromegalia/genética , Acromegalia/fisiopatologia , Diagnóstico Diferencial , Agonistas de Dopamina/uso terapêutico , Fadiga/etiologia , Hormônio do Crescimento/análise , Hormônio do Crescimento/metabolismo , Hormônio do Crescimento Humano/análogos & derivados , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Hiperidrose/etiologia , Incidência , Fator de Crescimento Insulin-Like I/análise , Imagem por Ressonância Magnética/métodos , Programas de Rastreamento/métodos , Neoplasias Hipofisárias/complicações , Qualidade de Vida/psicologia , Radioterapia/métodos
3.
Vnitr Lek ; 65(1): 51-54, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30823838

RESUMO

Acromegaly is a rare disorder usually caused by a benign tumour of the pituitary gland. Long-term presence of elevated growth hormone (GH) and insulin like growth factor 1 (IGF1) levels accompanying this disease is associated with complications such as cardiomyopathy, diabetes mellitus, sleep apnoea and arthropathy. Incidence of acromegaly is 3-4 patients per million per year. Klinefelter syndrome (KS) is the most common sex chromosome disorder occuring in about 1/500 live male births. Common physical features include particularly small testes, among other symptoms are tall stature, reduced muscle tone, delayed pubertal development, lack of secondary male sex characteristics and gynecomastia. We present a 32-year-old man suffering from both acromegaly and 47, XXY Klinefelter syndrome. The patient with typical acromegalic features. Laboratory tests revealed high level of GH which was not suppressed after glucose administration, high level of IGF1, low testosterone concentration with high concentation of luteinizing hormone and follicle stimulating hormone. A magnetic resonance imaging scan revealed a 25 × 18 × 18 mm macroadenoma involving the pituitary gland. A diagnosis of acromegaly was established. After this examination trans-sphenoidal resection was performed. Histopathologic and immunohistochemical findings revealed growth hormoneproducing pituitary adenoma. The presence of infertility with clinical features such as small testes, lack of secondary male sex characteristics and laboratory findings revealed hypergonadotropic hypogonadism that could not be explained by the diagnosis of acromegaly. A chromosomal karyotyping revealed a 47, XXY, confirming the diagnosis of KS. Testosterone replacement therapy wasn´t begun because of patient disagreement Postoperatively elevated plasma concentration of GH and IGF1 levels persist. Treatment by somatostatin analogues (lanreotid) was initiated at dose 120 mg every 28 days. Control magnetic resonance imaging of the sella demonstrated a residue of pituary adenoma size 14 × 14 × 7 mm. The patient is currently undergoing endoscopic revision of the residue. acromegaly - growth hormone - IGF1 - Klinefelter syndrome - testosterone.


Assuntos
Acromegalia , Adenoma , Síndrome de Klinefelter , Neoplasias Hipofisárias , Acromegalia/complicações , Acromegalia/diagnóstico , Acromegalia/genética , Adenoma/complicações , Adenoma/diagnóstico , Adenoma/genética , Adulto , Hormônio do Crescimento Humano , Humanos , Fator de Crescimento Insulin-Like I , Síndrome de Klinefelter/complicações , Síndrome de Klinefelter/diagnóstico , Síndrome de Klinefelter/genética , Masculino , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/genética
4.
Prog Mol Biol Transl Sci ; 161: 47-67, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30711029

RESUMO

X-linked acrogigantism (XLAG) is a recently described early-onset gigantism due to GPR101 duplication that induces growth hormone (GH) oversecretion. GPR101, which belongs to Family A rhodopsin-like family of G protein-coupled receptors, is predominantly expressed in hypothalamus and pituitary, suggesting that GPR101 might be important in regulating diverse functions such as energy balance and reproduction. Most mammalian GPR101s have extremely long third intracellular loops (ICL3); however, zebrafish GPR101 has a much shorter ICL3, but a longer C-terminus. GnRH-(1-5), a GnRH metabolite, can modulate the hypothalamus-pituitary-gonad axis and cancer cell migration via activating GPR101. GPR101 couples to both Gαs and Gαi proteins. GPR101 duplication has a causative role in XLAG, while GPR101 variants, especially c.924G>C (E308D), located at ICL3, are attributed to acromegaly. Some GPR101 mutations that are associated with a small proportion of pituitary tumors without GH oversecretion have also been identified recently. This chapter will summarize studies on GPR101, including its molecular cloning and tissue distribution, physiology, pharmacology, and pathophysiology.


Assuntos
Acromegalia/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Gigantismo/genética , Receptores Acoplados a Proteínas-G/genética , Sequência de Aminoácidos , Humanos , Modelos Biológicos , Mutação/genética , Receptores Acoplados a Proteínas-G/química
5.
Minerva Endocrinol ; 44(2): 109-128, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30650942

RESUMO

Acromegaly is a chronic systemic disease mainly caused by a growth hormone (GH)-secreting pituitary neuroendocrine tumor (PitNETs), which is associated with many health complications and increased mortality when not adequately treated. Transsphenoidal surgery is considered the treatment of choice in GH-secreting PitNETs, but patients in whom surgery cannot be considered or with persistent disease after surgery require medical therapy. Treatment with available synthetic somatostatin analogues (SSAs) is considered the mainstay in the medical management of acromegaly which exert their beneficial effects through the binding to a family of G-protein coupled receptors encoded by 5 genes (SSTR1-5). However, although it has been demonstrated that the SST1-5 receptors are physically present in tumor cells, SSAs are in many cases ineffective (i.e. approximately 10-30% of patients with GH-secreting PitNET are unresponsive to SSAs), suggesting that other cellular/molecular determinants could be essential for the response to the pharmacological treatment in patients with GH-secreting PitNETs. Therefore, the scrutiny of these determinants might be used for the identification of subgroups of patients in whom an appropriate pharmacological treatment can be successfully employed (responders vs. non-responders). In this review, we will describe some of the existing, classical and novel, genetic and molecular determinants involved in the response of patients with GH-secreting PitNETs to the available therapeutic treatments, as well as new molecular/therapeutic approaches that could be potentially useful for the treatment of GH-secreting PitNETs.


Assuntos
Acromegalia/tratamento farmacológico , Acromegalia/genética , Adenoma/tratamento farmacológico , Adenoma/genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/tratamento farmacológico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Humanos , Neoplasias Hipofisárias/complicações
6.
J Endocrinol Invest ; 42(7): 825-831, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30488289

RESUMO

PURPOSE: Biomarkers of clinical and therapeutic outcome in acromegaly are needed. Polymorphisms or epigenetic changes of detoxification genes, such as those coding for the aryl hydrocarbon receptor (AHR) and the glutathione-S-transferase-P1 (GSTP1), could have a role in GH secreting pituitary tumors' pathophysiology and clinical expression. In this study, we assessed the contribution of GSTP1 gene promoter methylation status, per se or in combination with the occurrence of the AHR gene rs2066853 variant, on clinical features and response to somatostatin analogs (SSA) treatment in acromegaly patients. METHODS: This is an observational, retrospective study, carried out in the Endocrine Unit of an Italian University Hospital. We enrolled 77 wild-type AIP gene acromegaly patients, who have been screened for germline AHR rs2066853 variant and GSTP1 gene promoter methylation. Clinical and biochemical parameters were compared after patients' stratification according to GSTP1 methylation status and the presence of AHR rs2066853. We also evaluated the response to SSA treatment in 71 cases. RESULTS: 17 patients carried the AHR rs2066853 variant and 26 had methylated GSTP1 (GSTP1-methyl) gene promoter. GSTP1-methyl patients showed a higher prevalence of diabetes mellitus (p = 0.01), colonic polyps (p = 0.05), and were more resistant to SSA (p = 0.02) as compared to GSTP1 unmethylated patients (GSTP1-unmethyl). Patients GSTP1-unmethyl and AHR wild-type were the most sensitive to SSA treatment, while those with both GSTP1-methyl and AHR rs2066853 variant were all resistant to SSA (p = 0.01). CONCLUSIONS: In acromegaly, GSTP1 gene methylation associates with resistance to SSA treatment, especially in patients carrying also the AHR rs2066853 variant, and with increased prevalence of colonic polyps and diabetes mellitus.


Assuntos
Acromegalia/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Biomarcadores/análise , Resistência a Medicamentos/genética , Glutationa S-Transferase pi/genética , Octreotida/uso terapêutico , Polimorfismo Genético , Receptores de Hidrocarboneto Arílico/genética , Acromegalia/tratamento farmacológico , Acromegalia/patologia , Antineoplásicos Hormonais/uso terapêutico , Metilação de DNA , Feminino , Seguimentos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Regiões Promotoras Genéticas , Estudos Retrospectivos
7.
Nat Rev Endocrinol ; 14(12): 705-720, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30361628

RESUMO

In the general population, height is determined by a complex interplay between genetic and environmental factors. Pituitary gigantism is a rare but very important subgroup of patients with excessive height, as it has an identifiable and clinically treatable cause. The disease is caused by chronic growth hormone and insulin-like growth factor 1 secretion from a pituitary somatotrope adenoma that forms before the closure of the epiphyses. If not controlled effectively, this hormonal hypersecretion could lead to extremely elevated final adult height. The past 10 years have seen marked advances in the understanding of pituitary gigantism, including the identification of genetic causes in ~50% of cases, such as mutations in the AIP gene or chromosome Xq26.3 duplications in X-linked acrogigantism syndrome. Pituitary gigantism has a male preponderance, and patients usually have large pituitary adenomas. The large tumour size, together with the young age of patients and frequent resistance to medical therapy, makes the management of pituitary gigantism complex. Early diagnosis and rapid referral for effective therapy appear to improve outcomes in patients with pituitary gigantism; therefore, a high level of clinical suspicion and efficient use of diagnostic resources is key to controlling overgrowth and preventing patients from reaching very elevated final adult heights.


Assuntos
Adenoma/complicações , Predisposição Genética para Doença/epidemiologia , Gigantismo/etiologia , Fator de Crescimento Insulin-Like I/genética , Neoplasias Hipofisárias/complicações , Acromegalia/etiologia , Acromegalia/genética , Acromegalia/terapia , Adenoma/diagnóstico , Adenoma/genética , Diagnóstico Precoce , Gigantismo/genética , Gigantismo/terapia , Hormônio do Crescimento Humano/metabolismo , Humanos , Masculino , Mutação , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/genética , Prognóstico , Medição de Risco , Fatores Sexuais
8.
BMC Med Genet ; 19(1): 182, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30290787

RESUMO

BACKGROUND: It has been reported that the single nucleotide polymorphism (SNP) rs2854744 at the - 202 locus of insulin-like growth factor binding protein-3 (IGFBP3) is associated with serum levels and a number of malignancies. However, the effect of IGFBP3 gene polymorphism on acromegaly is less clear. Therefore, in the current study, we aimed to investigate whether the -202A/C polymorphism of IGFBP3 constitutes a risk factor for acromegaly. METHODS: The study included 102 acromegalic patients and 143 control subjects in Beijing Tiantan Hospital. The genotyping of IGFBP3 was carried out using the MassARRAY method. Serum IGFBP3 concentrations were also determined. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the associations of genetic polymorphisms with the development of acromegaly and its different subtypes. RESULTS: The study revealed that the C allele of rs2854744 was associated with a reduced risk of acromegaly (OR 0.594, 95% CI 0.388-0.909), as well as with the female (OR 0.385, 95% CI 0.206-0.72), macroadenoma (OR 0.557, 95% CI 0.347-0.893) and monotherapy (OR 0.512, 95% CI 0.316-0.828) subgroups under the additive model. A higher serum IGFBP3 level was observed in patients with the AA genotype, but this difference was not significant (P = 0.331). CONCLUSION: This study is one of the first to show that the IGFBP3 polymorphism may have an influence on serum levels and that the C allele of rs2854744 is associated with a reduced risk of acromegaly. This correlation was more prominent in females, those with large tumours and those treated with monotherapy in a Chinese population. Genetic polymorphism of IGFBP3 may be involved in the development of acromegaly.


Assuntos
Acromegalia/genética , Adenoma/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Neoplasias Hipofisárias/genética , Polimorfismo de Nucleotídeo Único , Regiões 5' não Traduzidas , Acromegalia/sangue , Acromegalia/complicações , Acromegalia/etnologia , Adenoma/sangue , Adenoma/complicações , Adenoma/etnologia , Adulto , Alelos , Grupo com Ancestrais do Continente Asiático , Estudos de Casos e Controles , Feminino , Expressão Gênica , Frequência do Gene , Genótipo , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Masculino , Pessoa de Meia-Idade , Razão de Chances , Neoplasias Hipofisárias/sangue , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/etnologia , Fatores de Risco , Fatores Sexuais
9.
Clin Cancer Res ; 24(17): 4126-4136, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30084836

RESUMO

Purpose: Pituitary adenomas are one of the most common benign neoplasms of the central nervous system. Although emerging evidence suggests roles for both genetic and epigenetic factors in tumorigenesis, the degree to which these factors contribute to disease remains poorly understood.Experimental Design: A multiplatform analysis was performed to identify the genomic and epigenomic underpinnings of disease among the three major subtypes of surgically resected pituitary adenomas in 48 patients: growth hormone (GH)-secreting (n = 17), adrenocorticotropic hormone (ACTH)-secreting (n = 13, including 3 silent-ACTH adenomas), and endocrine-inactive (n = 18). Whole-exome sequencing was used to profile the somatic mutational landscape, whole-transcriptome sequencing was used to identify disease-specific patterns of gene expression, and array-based DNA methylation profiling was used to examine genome-wide patterns of DNA methylation.Results: Recurrent single-nucleotide and small indel somatic mutations were infrequent among the three adenoma subtypes. However, somatic copy-number alterations (SCNA) were identified in all three pituitary adenoma subtypes. Methylation analysis revealed adenoma subtype-specific DNA methylation profiles, with GH-secreting adenomas being dominated by hypomethylated sites. Likewise, gene-expression patterns revealed adenoma subtype-specific profiles. Integrating DNA methylation and gene-expression data revealed that hypomethylation of promoter regions are related with increased expression of GH1 and SSTR5 genes in GH-secreting adenomas and POMC gene in ACTH-secreting adenomas. Finally, multispectral IHC staining of immune-related proteins showed abundant expression of PD-L1 among all three adenoma subtypes.Conclusions: Taken together, these data stress the contribution of epigenomic alterations to disease-specific etiology among adenoma subtypes and highlight potential targets for future immunotherapy-based treatments. This article reveals novel insights into the epigenomics underlying pituitary adenomas and highlights how differences in epigenomic states are related to important transcriptome alterations that define adenoma subtypes. Clin Cancer Res; 24(17); 4126-36. ©2018 AACR.


Assuntos
Variações do Número de Cópias de DNA/genética , Metilação de DNA/genética , Epigenômica , Neoplasias Hipofisárias/genética , Acromegalia/genética , Acromegalia/patologia , Hormônio Adrenocorticotrópico/genética , Adulto , Idoso , Antígeno B7-H1/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Síndrome de Cushing/genética , Síndrome de Cushing/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Hormônio do Crescimento/genética , Humanos , Mutação INDEL/genética , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/classificação , Neoplasias Hipofisárias/patologia , Regiões Promotoras Genéticas/genética , Receptores de Somatostatina/genética , Transcriptoma/genética , Sequenciamento Completo do Exoma
10.
Horm Res Paediatr ; 90(3): 196-202, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29953972

RESUMO

BACKGROUND: Somatotropinomas are rare in childhood and frequently associated with genetic mutations. AIP mutations are found in 20-25% cases and cause aggressive somatotropinomas, often resistant to somatostatin analogues. AIMS: To assess responses to multimodal therapy including pegvisomant in 2 children with sporadic somatotropinomas due to AIP mutations. CASE DESCRIPTION: We report 2 children, a boy aged 13 and a girl aged 10, with rapid growth, visual impairment, and growth hormone hypersecretion. Magnetic resonance imaging confirmed a pituitary macroadenoma with parasellar extension in both. Despite multiple surgical attempts to debulk tumour mass, residual tumour persisted. Genetic analysis showed two different AIP mutations (patient 1: c.562delC [p.Arg188Glyfs*8]; patient 2: c.140_ 163del24 [p.Gly47_Arg54del8]). They were initially treated with a long-acting somatostatin analogue (octreotide LAR 30 mg/month) and cabergoline as a dopamine agonist, with the later addition of pegvisomant titrated up to 20 mg/day and with radiotherapy for long-term control. Somatostatin analogue was ceased due to patient intolerance and lack of control. Patient 1 had normalization of insulin-like growth factor-1 (IGF-1) after 5 months of combined therapy with pegvisomant and cabergoline. For patient 2, normalization of IGF-1 was achieved after 2 months of cabergoline and pegvisomant. CONCLUSION: AIP-associated tumours can be resistant to management with somatostatin analogues. Pegvisomant can safely be used, to normalize IGF-1 levels and help control disease.


Assuntos
Adenoma/tratamento farmacológico , Adenoma/genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/tratamento farmacológico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Hormônio do Crescimento Humano/análogos & derivados , Peptídeos e Proteínas de Sinalização Intracelular/genética , Acromegalia/diagnóstico , Acromegalia/tratamento farmacológico , Acromegalia/genética , Acromegalia/metabolismo , Adenoma/diagnóstico , Adenoma/metabolismo , Adolescente , Criança , Feminino , Gráficos de Crescimento , Adenoma Hipofisário Secretor de Hormônio do Crescimento/diagnóstico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/metabolismo , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Imagem por Ressonância Magnética , Masculino
12.
Best Pract Res Clin Endocrinol Metab ; 32(2): 125-140, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29678281

RESUMO

X-linked acrogigantism (X-LAG) is a recently described form of familial or sporadic pituitary gigantism characterized by very early onset GH and IGF-1 excess, accelerated growth velocity, gigantism and/or acromegaloid features. Germline or somatic microduplications of the Xq26.3 chromosomal region, invariably involving the GPR101 gene, constitute the genetic defect leading to X-LAG. GPR101 encodes a class A G protein-coupled receptor that activates the 3',5'-cyclic adenosine monophosphate signaling pathway. Highly expressed in the central nervous system, the main physiological function and ligand of GPR101 remain unknown, but it seems to play a role in the normal development of the GHRH-GH axis. Early recognition of X-LAG cases is imperative because these patients require clinical management that differs from that of other patients with acromegaly or gigantism. Medical treatment with pegvisomant seems to be the best approach, since X-LAG tumors are resistant to the treatment with somatostatin analogues and dopamine agonists; surgical cure requires near-total hypophysectomy. Currently, the efforts of our research focus on the identification of GPR101 ligands; in addition, the long-term follow-up of X-LAG patients is of extreme interest as this is expected to lead to better understanding of GPR101 effects on human pathophysiology.


Assuntos
Acromegalia/genética , Acromegalia/patologia , Gigantismo/genética , Gigantismo/patologia , Receptores Acoplados a Proteínas-G/fisiologia , Predisposição Genética para Doença , Humanos , Fator de Crescimento Insulin-Like I/fisiologia , Receptores Acoplados a Proteínas-G/genética
13.
Pituitary ; 21(4): 335-346, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29455389

RESUMO

OBJECTIVE: To determine aryl hydrocarbon interacting protein (AIP) gene variations and AIP and somatostatin receptor (SSTR) 1-5 immunostaining in patients with apparently sporadic acromegaly with poor versus good response to somatostatin analogues (SRLs). METHODS: A total of 94 patients (66 with poor and 28 with good response to SRLs) were screened for the AIP gene variations using Sanger sequencing. Immunostaining was performed in 60 tumors. RESULTS: Several variations, albeit some with undetermined significance, were detected, especially in poor responder patients. The prevalence of AIP mutation was 2.1% in the whole group and 1.5% in patients with poor response to SRLs. AIP, SSTR2A, and SSTR2B immunostainings were decreased in patients with poor response (p < 0.05 for all), and other SSTRs did not differ between the groups (p > 0.05 for all). Patients with low AIP had decreased levels of SSTR2A and SSTR3 (p < 0.05 for all). AIP and SSTR2A immunostainings were positively correlated to the treatment response and age at diagnosis was negatively correlated (p < 0.05 for all). In poor responder patients with high SSTR2A immunostaining, SSTR2B immunostaining and preoperative tumor size were positively and negatively correlated, respectively, to SRL response (p < 0.05 for all). CONCLUSIONS: Lack of response to SRLs does not necessarily increase the risk of harboring AIP mutations. The finding of decreased AIP, SSTR2A, and SSTR2B immunostaining in patients with poor response to SRLs and decreased SSTR2A and SSTR3 level in those with low AIP immunostaining suggests a possible interaction between AIP and some SSTR subtypes that might alter SRL sensitivity.


Assuntos
Acromegalia/tratamento farmacológico , Acromegalia/genética , Mutação em Linhagem Germinativa/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Receptores de Somatostatina/genética , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Adulto , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
14.
J Clin Endocrinol Metab ; 103(5): 1929-1939, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29474559

RESUMO

Purpose: The molecular pathogenesis of growth hormone-secreting pituitary adenomas is not fully understood. Cytogenetic alterations might serve as alternative driver events in GNAS mutation-negative somatotroph tumors. Experimental Design: We performed cytogenetic profiling of pituitary adenomas obtained from 39 patients with acromegaly and four patients with sporadic gigantism by using array comparative genomic hybridization analysis. We explored intratumor DNA copy-number heterogeneity in two tumor samples by using DNA fluorescence in situ hybridization (FISH). Results: Based on copy-number profiles, we found two groups of adenomas: a low-copy-number alteration (CNA) group (<12% of genomic disruption, 63% of tumors) and a high-CNA group (24% to 45% of genomic disruption, 37% of tumors). Arm-level CNAs were the most common abnormalities. GNAS mutation-positive adenomas belonged exclusively to the low-CNA group, whereas a subgroup of GNAS mutation-negative adenomas had a high degree of genomic disruption. We detected chromothripsis-related CNA profiles in two adenoma samples from an AIP mutation-positive patient with acromegaly and a patient with sporadic gigantism. RNA sequencing of these two samples identified 17 fusion transcripts, most of which resulted from chromothripsis-related chromosomal rearrangements. DNA FISH analysis of these samples demonstrated a subclonal architecture with up to six distinct cell populations in each tumor. Conclusion: Somatotroph pituitary adenomas display substantial intertumor and intratumor DNA copy-number heterogeneity, as revealed by variable CNA profiles and complex subclonal architecture. The extensive cytogenetic burden in a subgroup of GNAS mutation-negative somatotroph adenomas points to an alternative tumorigenic pathway linked to genomic instability.


Assuntos
Adenoma/genética , Adenoma/patologia , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Acromegalia/genética , Acromegalia/patologia , Adulto , Aberrações Cromossômicas , Evolução Clonal/genética , Hibridização Genômica Comparativa , Análise Citogenética , Variações do Número de Cópias de DNA , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Mutação
15.
Eur J Endocrinol ; 178(4): 353-364, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29374071

RESUMO

OBJECTIVE: To evaluate the response of bone to chronic long-term growth hormone (GH) and insulin-like growth factor-1 (IGF1) excess by measuring the expression of selected mRNA and microRNA (miR) in bone tissue samples of patients with active acromegaly. DESIGN: Case-control study. METHODS: Bone tissue samples were obtained during transsphenoidal adenomectomy from the sphenoid bone (sella turcica) from 14 patients with clinically and biochemically confirmed acromegaly and 10 patients with clinically non-functioning pituitary adenoma (NFPA) matched by sex and age. Expression of genes involved in the regulation of bone remodeling was studied using quantitative polymerase chain reaction (qPCR). RESULTS: Of the genes involved in osteoblast and osteoclast activity, only alkaline phosphatase (ALP) mRNA was 50% downregulated in patients with acromegaly. GH excess caused increased expression of the Wnt signaling antagonists (DKK1) and agonists (WNT10B) and changes in the levels of miR involved in mesenchymal stem cell commitment to chondrocytes (miR-199a-5p) or adipocytes (miR-27-5p, miR-125b-5p, miR-34a-5p, miR-188-3p) P < 0.05; q < 0.1. Relevant compensatory mechanisms were found through the changes in miR involved in osteoblastogenesis (miR-210-5p, miR-135a-5p, miR-211, miR-23a-3p, miR-204-5p), but the expression of TWIST1 was 50% downregulated and RUNX2 was unchanged. CONCLUSIONS: Acromegaly had minimal effects on tested mRNAs specific to osteoblast or osteoclast function except for downregulated ALP expression. The expressions of miR known to be involved in mesenchymal stem cell commitment and downregulated TWIST1 expression suggest acromegaly has a negative effect on osteoblastogenesis.


Assuntos
Acromegalia/metabolismo , Hormônio do Crescimento Humano/biossíntese , MicroRNAs/biossíntese , RNA Mensageiro/biossíntese , Osso Esfenoide/metabolismo , Acromegalia/diagnóstico , Acromegalia/genética , Adulto , Estudos de Casos e Controles , Estudos Transversais , Feminino , Expressão Gênica , Hormônio do Crescimento Humano/genética , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , RNA Mensageiro/genética , Osso Esfenoide/patologia
16.
J Cell Mol Med ; 22(4): 2110-2116, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29377493

RESUMO

ß-arrestins seem to have a role in endocytosis and desensitization of somatostatin receptor subtype 2 (sst2) and could be associated with the responsiveness to somatostatin receptor ligands (SRL) in patients with acromegaly. To investigate the in vivo correlation between ß-arrestins 1 and 2 with sst2, sst5 and dopamine receptor subtype 2 (D2) expressions, and the association of ß-arrestins with response to first-generation SRL and invasiveness in somatotropinomas. ß-arrestins 1 and 2, sst2, sst5 and D2 mRNA expressions were evaluated by quantitative real-time RT-PCR on tumoral tissue of 96 patients. Moreover, sst2 and sst5 protein expressions were also evaluated in 40 somatotropinomas by immunohistochemistry. Response to SRL, defined as GH <1 µg/l and normal IGF-I levels, was assessed in 40 patients. The Knosp-Steiner criteria were used to define invasiveness. Median ß-arrestin 1, ß-arrestin 2, sst2, sst5 and D2 mRNA copy numbers were 478; 9375; 731; 156; and 3989, respectively. There was a positive correlation between ß-arrestins 1 and 2 (R = 0.444, P < 0.001). However, no correlation between ß-arrestins and sst2, sst5 (mRNA and protein levels) or D2 was found. No association was found between ß-arrestins expression and SRL responsiveness or tumour invasiveness. Although previous data suggest a putative correlation between ß-arrestins and sst2, our data clearly indicated that no association existed between ß-arrestins and sst2, sst5 or D2 expression, nor with response to SRL or tumour invasiveness. Therefore, further studies are required to clarify whether ß-arrestins have a role in the response to treatment with SRL in acromegaly.


Assuntos
Acromegalia/genética , beta-Arrestinas/genética , Adolescente , Adulto , Idoso , Feminino , Regulação da Expressão Gênica , Humanos , Ligantes , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Somatostatina/metabolismo , Adulto Jovem , beta-Arrestinas/metabolismo
17.
Endocr Relat Cancer ; 25(3): 269-277, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29295822

RESUMO

Acromegalic patients, characterized by excessive secretion of GH and IGF-1, show a high fracture risk but bone mineral density is a poor predictor for bone fractures in these patients. The effects of an excess of GH/IGF1 on skeleton as well as on osteogenic progenitors, i.e. mesenchymal stem cells, have not been investigated in these patients. We aimed to elucidate the skeletal conditions of acromegalic patients by means of bone microarchitecture analysis and evaluation of MSCs osteogenic commitment. In particular, we performed histomorphometric analyses, and we quantified the expression levels of the osteogenic transcription factor RUNX2 in circulating MSCs. Our results showed an abnormal microarchitecture and demonstrated that bone impairment in acromegalic patients is associated with the upregulation of RUNX2 expression. Furthermore, osteoblastic activity was significantly reduced in patients under pharmacological treatment, compared to untreated patients. In conclusion, this study demonstrates the key role of RUNX2 gene overexpression in causing bone impairment in acromegalic patients. It also suggests a therapeutic approach for the improvement of bone quality, focused on the osteoblastic lineage rather than the inhibition of osteoclastic activity.


Assuntos
Acromegalia/genética , Osso e Ossos/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Acromegalia/metabolismo , Adulto , Idoso , Densidade Óssea , Diferenciação Celular , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regulação para Cima , Adulto Jovem
18.
Obstet Gynecol ; 131(1): 96-99, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29215515

RESUMO

BACKGROUND: Isolated absent thelarche is a rare condition that is infrequently reviewed in the literature. CASE: A 28-year-old woman with neurofibromatosis type 1 and acromegaly presented with absent breast development despite hormone therapy. Examination noted a normally developed woman with acromegalic features and Tanner stage I breasts. Hormone studies and karyotype were normal. Magnetic resonance imaging of the patient's brain demonstrated a voluminous pituitary. Chromosome microarray analysis diagnosed the neurofibromatosis 1 microdeletion syndrome. Breast ultrasonography and surgical consultation were offered. CONCLUSIONS: Neither neurofibromatosis type 1, acromegaly, nor neurofibromatosis 1 microdeletion syndrome are linked to absent thelarche. After attempting hormone therapy, patients with absent thelarche should be evaluated for congenital breast anomalies, estrogen receptor abnormalities, or gene defects. Psychological and surgical consultation should also be offered.


Assuntos
Acromegalia/diagnóstico , Mama/anormalidades , Estrogênios/uso terapêutico , Neurofibromatose 1/diagnóstico , Acromegalia/complicações , Acromegalia/genética , Adulto , Mama/efeitos dos fármacos , Mama/crescimento & desenvolvimento , Feminino , Humanos , Neurofibromatose 1/complicações , Neurofibromatose 1/genética , Doenças Raras , Medição de Risco , Falha de Tratamento
19.
Pituitary ; 21(1): 10-15, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28913579

RESUMO

INTRODUCTION: Cardiovascular diseases are main cause of morbidity and mortality in acromegaly. Polymorphisms of FTO gene are associated with obesity and increased risk of CVD (independently of BMI). Aim of this study was to investigate the allele frequencies of two FTO gene polymorphisms: rs9939609 and rs9930506 in patients with acromegaly and to examine the association of FTO gene polymorphisms with BMI and selected metabolic parameters. MATERIALS AND METHODS: Identification of two single nucleotide polymorphisms of FTO gene was carried out in 51 patients with acromegaly using the minisequencing method. RESULTS: The risk-allele frequencies of rs9939609 and rs9930506 polymorphisms were 0.471 and 0.529, respectively and they were higher than in general European population. There is no association of FTO gene polymorphisms with BMI, glucose, total cholesterol, LDL cholesterol and triglyceride. The risk alleles were associated with decreased HDL cholesterol concentration. Homozygotes for the rs9939609-risk allele had 1.25-fold lower HDL cholesterol concentration than carriers of the TT genotype (p = 0.0024). The estimated average decrease in HDL cholesterol concentration per risk allele for rs9930506 was 11.2%. Nevertheless, statistically significant differences were observed only between AG versus GG and AA versus GG genotypes. Homozygotes for the rs9930506-risk allele had 1.27-fold lower HDL cholesterol concentration than carriers of the AA genotype (p = 0.007). CONCLUSION: The risk-allele frequencies of studied polymorphisms in acromegaly were higher than in general European population. There is an association between FTO gene polymorphisms and HDL cholesterol concentration, suggesting FTO gene polymorphisms may be associated with higher CVD risk in patients with acromegaly.


Assuntos
Acromegalia/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Doenças Cardiovasculares/genética , HDL-Colesterol/sangue , Polimorfismo de Nucleotídeo Único , Acromegalia/sangue , Acromegalia/diagnóstico , Acromegalia/etnologia , Adulto , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etnologia , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Polônia/epidemiologia , Fatores de Risco
20.
Braz J Med Biol Res ; 51(2): e6808, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29267504

RESUMO

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.


Assuntos
Acromegalia/patologia , Adenoma/patologia , Caderinas/análise , Moléculas de Adesão de Célula Nervosa/análise , Neoplasias Hipofisárias/patologia , Fatores de Transcrição da Família Snail/análise , Acromegalia/genética , Acromegalia/metabolismo , Adenoma/química , Adenoma/genética , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/análise , Antígeno CD56/análise , Estudos Transversais , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Neoplasias Hipofisárias/química , Neoplasias Hipofisárias/genética , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não Paramétricas , Adulto Jovem
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