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1.
Int J Mol Sci ; 24(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37298217

RESUMO

The glucose-dependent insulinotropic polypeptide receptor (GIPR) is aberrantly expressed in about one-third of GH-secreting pituitary adenomas (GH-PAs) and has been associated with a paradoxical increase of GH after a glucose load. The reason for such an overexpression has not yet been clarified. In this work, we aimed to evaluate whether locus-specific changes in DNA methylation patterns could contribute to this phenomenon. By cloning bisulfite-sequencing PCR, we compared the methylation pattern of the GIPR locus in GIPR-positive (GIPR+) and GIPR-negative (GIPR-) GH-PAs. Then, to assess the correlation between Gipr expression and locus methylation, we induced global DNA methylation changes by treating the lactosomatotroph GH3 cells with 5-aza-2'-deoxycytidine. Differences in methylation levels were observed between GIPR+ and GIPR- GH-PAs, both within the promoter (31.9% vs. 68.2%, p < 0.05) and at two gene body regions (GB_1 20.7% vs. 9.1%; GB_2 51.2% vs. 65.8%, p < 0.05). GH3 cells treated with 5-aza-2'-deoxycytidine showed a ~75% reduction in Gipr steady-state level, possibly associated with the observed decrease in CpGs methylation. These results indicate that epigenetic regulation affects GIPR expression in GH-PAs, even though this possibly represents only a part of a much more complex regulatory mechanism.


Assuntos
Adenoma , Adenoma Hipofisário Secretor de Hormônio do Crescimento , Receptores dos Hormônios Gastrointestinais , Humanos , Adenoma/genética , Adenoma/metabolismo , Decitabina , Metilação de DNA , Epigênese Genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Receptores dos Hormônios Gastrointestinais/metabolismo
2.
Int J Mol Sci ; 23(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35742910

RESUMO

Adrenocorticotropic Hormone (ACTH)-secreting pituitary adenomas are rare tumors characterized by autonomous ACTH secretion with a consequent increase in circulating cortisol levels. The resulting clinical picture is called Cushing's disease (CD), a severe condition burdened with high morbidity and mortality. Apart from increased cortisol levels, CD patients exhibit a partial resistance to the negative glucocorticoid (GC) feedback, which is of paramount clinical utility, as the lack of suppression after dexamethasone administration is one of the mainstays for the differential diagnosis of CD. Since the glucocorticoid receptor (GR) is the main regulator of negative feedback of the hypothalamic-pituitary-adrenal axis in normal conditions, its implication in the pathophysiology of ACTH-secreting pituitary tumors is highly plausible. In this paper, we review GR function and structure and the mechanisms of GC resistance in ACTH-secreting pituitary tumors and assess the effects of the available medical therapies targeting GR on tumor growth.


Assuntos
Adenoma Hipofisário Secretor de ACT , Adenoma , Hipersecreção Hipofisária de ACTH , Neoplasias Hipofisárias , Hormônio Adrenocorticotrópico/metabolismo , Glucocorticoides/uso terapêutico , Humanos , Hidrocortisona , Sistema Hipotálamo-Hipofisário/metabolismo , Hipersecreção Hipofisária de ACTH/patologia , Sistema Hipófise-Suprarrenal/metabolismo , Receptores de Glucocorticoides
3.
Rev Endocr Metab Disord ; 21(1): 165-183, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31933128

RESUMO

The glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone produced in the gastrointestinal tract in response to nutrients. GIP has a variety of effects on different systems, including the potentiation of insulin secretion from pancreatic ß-cells after food intake (i.e. incretin effect), which is probably the most important. GIP effects are mediated by the GIP receptor (GIPR), a G protein-coupled receptor expressed in several tissues, including islet ß-cells, adipocytes, bone cells, and brain. As well as its involvement in metabolic disorders (e.g. it contributes to the impaired postprandial insulin secretion in type 2 diabetes (T2DM), and to the pathogenesis of obesity and associated insulin resistance), an inappropriate GIP/GIPR axis activation of potential diagnostic and prognostic value has been reported in several endocrine tumors in recent years. The ectopic GIPR expression seen in patients with overt Cushing syndrome and primary bilateral macronodular adrenal hyperplasia or unilateral cortisol-producing adenoma has been associated with an inverse rhythm of cortisol secretion, with low fasting morning plasma levels that increase after eating. On the other hand, most acromegalic patients with an unusual GH response to oral glucose suppression have GIPR-positive somatotropinomas, and a milder phenotype, and are more responsive to medical treatment. Neuroendocrine tumors are characterized by a strong GIPR expression that may correlate positively or inversely with the proliferative index MIB-1, and that seems an attractive target for developing novel radioligands. The main purpose of this review is to summarize the role of the GIP/GIPR axis in endocrine neoplasia, in the experimental and the clinical settings.


Assuntos
Polipeptídeo Inibidor Gástrico/metabolismo , Tumores Neuroendócrinos/metabolismo , Receptores dos Hormônios Gastrointestinais/metabolismo , Adenoma/metabolismo , Diabetes Mellitus Tipo 2 , Regulação Neoplásica da Expressão Gênica , Adenoma Hipofisário Secretor de Hormônio do Crescimento/metabolismo , Humanos , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Receptores dos Hormônios Gastrointestinais/genética
4.
PLoS Genet ; 9(3): e1003350, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23555276

RESUMO

The CDKN1B gene encodes the cyclin-dependent kinase inhibitor p27(KIP1), an atypical tumor suppressor playing a key role in cell cycle regulation, cell proliferation, and differentiation. Impaired p27(KIP1) expression and/or localization are often observed in tumor cells, further confirming its central role in regulating the cell cycle. Recently, germline mutations in CDKN1B have been associated with the inherited multiple endocrine neoplasia syndrome type 4, an autosomal dominant syndrome characterized by varying combinations of tumors affecting at least two endocrine organs. In this study we identified a 4-bp deletion in a highly conserved regulatory upstream ORF (uORF) in the 5'UTR of the CDKN1B gene in a patient with a pituitary adenoma and a well-differentiated pancreatic neoplasm. This deletion causes the shift of the uORF termination codon with the consequent lengthening of the uORF-encoded peptide and the drastic shortening of the intercistronic space. Our data on the immunohistochemical analysis of the patient's pancreatic lesion, functional studies based on dual-luciferase assays, site-directed mutagenesis, and on polysome profiling show a negative influence of this deletion on the translation reinitiation at the CDKN1B starting site, with a consequent reduction in p27(KIP1) expression. Our findings demonstrate that, in addition to the previously described mechanisms leading to reduced p27(KIP1) activity, such as degradation via the ubiquitin/proteasome pathway or non-covalent sequestration, p27(KIP1) activity can also be modulated by an uORF and mutations affecting uORF could change p27(KIP1) expression. This study adds the CDKN1B gene to the short list of genes for which mutations that either create, delete, or severely modify their regulatory uORFs have been associated with human diseases.


Assuntos
Inibidor de Quinase Dependente de Ciclina p27 , Predisposição Genética para Doença , Neoplasia Endócrina Múltipla/genética , Biossíntese de Proteínas , Regiões 5' não Traduzidas , Ciclo Celular , Diferenciação Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Células HeLa , Humanos , Neoplasia Endócrina Múltipla/metabolismo , Neoplasia Endócrina Múltipla/patologia , Mutagênese Sítio-Dirigida , Mutação , Fases de Leitura Aberta/genética
5.
J Neurooncol ; 122(1): 189-96, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25555563

RESUMO

Aggressive pituitary adenomas (PAs) are clinically challenging for endocrinologists and neurosurgeons due to their locally invasive nature and resistance to standard treatment (surgery, medical or radiotherapy). Two pituitary-directed drugs have recently been proposed: temozolomide (TMZ) for aggressive PA, and pasireotide for ACTH-secreting PA. We describe the experience of our multidisciplinary team of endocrinologists, neurosurgeons, neuroradiologists, oncologists, otolaryngologists and pathologists with TMZ and pasireotide treatment for aggressive PAs in terms of their radiological shrinkage and genetic features. We considered five patients with aggressive PA, three of them non-secreting (two ACTH-silent and one becoming ACTH secreting), and two secreting (one GH and one ACTH). TMZ was administrated orally at 150-200 mg/m(2) daily for 5 days every 28 days to all 5 patients, and 2 of them also received pasireotide 600-900 µg bid sc. We assessed the MRI at the baseline and during TMZ or pasireotide treatment. We also checked for MGMT promoter methylation and IDH, BRAF and kRAS mutations. Considering TMZ, two patients showed PA progression, one stable disease and two achieved radiological and clinical response. Pasireotide was effective in reducing hypercortisolism and mass volume, combined with TMZ in one case. Both treatments were generally well tolerated; one patient developed a grade 2 TMZ-induced thrombocytopenia. None of patients developed hypopituitarism while taking TMZ or pasireotide treatment. No genetic anomalies were identified in the adenoma tissue. TMZ and pasireotide may be important therapies for aggressive PA, alone or in combination.


Assuntos
Adenoma/tratamento farmacológico , Antineoplásicos Alquilantes/uso terapêutico , Dacarbazina/análogos & derivados , Neoplasias Hipofisárias/tratamento farmacológico , Somatostatina/análogos & derivados , Adenoma/mortalidade , Adenoma/patologia , Adulto , Idoso , Dacarbazina/uso terapêutico , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Hipofisárias/mortalidade , Neoplasias Hipofisárias/patologia , Prognóstico , Estudos Retrospectivos , Somatostatina/uso terapêutico , Taxa de Sobrevida , Temozolomida , Centros de Atenção Terciária
6.
Artigo em Inglês | MEDLINE | ID: mdl-38878276

RESUMO

CONTEXT: a paradoxical growth hormone (GH) response to oral glucose load (OGTT) in acromegaly is associated with a milder phenotype. OBJECTIVE: To study whether the GH response to OGTT predicts the risk of recurrence after initial surgical cure. DESIGN: Retrospective, observational study. SETTING: Two tertiary care centers. PATIENTS: We investigated 254 patients with acromegaly who were cured by surgery. INTERVENTION: All patients underwent OGTT at diagnosis before pituitary surgery. A peak-to-basal GH ratio ≥ 120% within 90 minutes was used to distinguish paradoxical (GH-Par) from non-paradoxical acromegalic patients (GH-NPar). MAIN OUTCOME MEASURE: Cox analysis was used to investigate whether the paradoxical GH response to OGTT was associated with the risk of disease recurrence. RESULTS: A paradoxical GH response to OGTT occurred in 87 patients (34.3%, termed GH-Par group). Recurrence of acromegaly occurred in three patients of the GH-Par group (3.4%) and in 20 patients in the GH-NPar group (12.0%). In the multivariate analysis, the paradoxical GH response to OGTT was significantly associated with the risk of recurrence (HR 0.18, 95% CI, 0.05-0.63; P = 0.007). Basal GH level at diagnosis was the only other variable associated with the risk of disease recurrence (HR 1.58, 95% CI, 1.01-2.47; P = 0.04). CONCLUSIONS: our study demonstrates that a paradoxical GH response to OGTT in the preoperative setting predicts a lower risk of disease recurrence after initial surgical cure. The pattern of GH responsiveness to OGTT is, therefore, useful to predict the long-term outcome of patients with acromegaly.

7.
Eur J Endocrinol ; 190(1): K8-K16, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38123488

RESUMO

OBJECTIVE: Somatostatin receptor ligands have come to play a pivotal role in the treatment of both ACTH- and GH-secreting pituitary adenomas. Clinical efficacy averages 30-50%, thus a considerable number of patients with Cushing's disease or acromegaly remain unresponsive to this therapeutic approach. HTL0030310 is a new somatostatin receptor ligand selective for subtype 5 over subtype 2, thus with a different receptor profile compared to clinical somatostatin receptor ligands. DESIGN: Assessment of the effect of HTL0030310 on hormone secretion in human ACTH- and GH-secreting pituitary adenomas in vitro. METHODS: Primary cultures from 3 ACTH-secreting and 5 GH-secreting pituitary adenomas were treated with 1, 10 and 100 nM HTL0030310 alone or with 10 nM CRH or GHRH, respectively. Parallel incubations with 10 nM pasireotide were also carried out. ACTH and GH secretion were assessed after 4 and 24 hour incubation; SSTR2, SSTR3, SSTR5, GH and POMC expression were evaluated after 24 hours. RESULTS: HTL0030310 reduced unchallenged ACTH and POMC levels up to 50% in 2 ACTH-secreting adenomas and blunted CRH-stimulated ACTH/POMC by 20-70% in all 3 specimens. A reduction in spontaneous GH secretion was observed in 4 GH-secreting adenomas and in 2 specimens during GHRH co-incubation. SSTRs expression was detected in all specimens. CONCLUSIONS: This first study on a novel somatostatin receptor 5-preferring ligand indicates that HTL0030310 can inhibit hormonal secretion in human ACTH- and GH-secreting pituitary adenomas. These findings suggest a potential new avenue for somatostatin ligands in the treatment of Cushing's disease and acromegaly.


Assuntos
Acromegalia , Adenoma , Adenoma Hipofisário Secretor de Hormônio do Crescimento , Hipersecreção Hipofisária de ACTH , Neoplasias Hipofisárias , Humanos , Receptores de Somatostatina/metabolismo , Neoplasias Hipofisárias/tratamento farmacológico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/tratamento farmacológico , Acromegalia/tratamento farmacológico , Pró-Opiomelanocortina/metabolismo , Hipersecreção Hipofisária de ACTH/tratamento farmacológico , Ligantes , Adenoma/metabolismo , Hormônio Adrenocorticotrópico/metabolismo
8.
Eur J Endocrinol ; 190(2): 173-181, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38330165

RESUMO

IMPORTANCE: A paradoxical increase of growth hormone (GH) following oral glucose load has been described in ∼30% of patients with acromegaly and has been related to the ectopic expression of the glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) in somatotropinomas. Recently, we identified germline pathogenic variants and somatic loss of heterozygosity of lysine demethylase 1A (KDM1A) in patients with GIP-dependent primary bilateral macronodular adrenal hyperplasia with Cushing's syndrome. The ectopic expression of GIPR in both adrenal and pituitary lesions suggests a common molecular mechanism. OBJECTIVE: We aimed to analyze KDM1A gene sequence and KDM1A and GIPR expressions in somatotroph pituitary adenomas. SETTINGS: We conducted a cohort study at university hospitals in France and in Italy. We collected pituitary adenoma specimens from acromegalic patients who had undergone pituitary surgery. We performed targeted exome sequencing (gene panel analysis) and array-comparative genomic hybridization on somatic DNA derived from adenomas and performed droplet digital PCR on adenoma samples to quantify KDM1A and GIPR expressions. RESULTS: One hundred and forty-six patients with sporadic acromegaly were studied; 72.6% presented unsuppressed classical GH response, whereas 27.4% displayed a paradoxical rise in GH after oral glucose load. We did not identify any pathogenic variant in the KDM1A gene in the adenomas of these patients. However, we identified a recurrent 1p deletion encompassing the KDM1A locus in 29 adenomas and observed a higher prevalence of paradoxical GH rise (P = .0166), lower KDM1A expression (4.47 ± 2.49 vs 8.56 ± 5.62, P < .0001), and higher GIPR expression (1.09 ± 0.92 vs 0.43 ± 0.51, P = .0012) in adenomas from patients with KDM1A haploinsufficiency compared with those with 2 KDM1A copies. CONCLUSIONS AND RELEVANCE: Unlike in GIP-dependent primary bilateral macronodular adrenal hyperplasia, KDM1A genetic variations are not the cause of GIPR expression in somatotroph pituitary adenomas. Recurrent KDM1A haploinsufficiency, more frequently observed in GIPR-expressing adenomas, could be responsible for decreased KDM1A function resulting in transcriptional derepression on the GIPR locus.


Assuntos
Acromegalia , Adenoma , Adenoma Hipofisário Secretor de Hormônio do Crescimento , Hormônio do Crescimento Humano , Neoplasias Hipofisárias , Somatotrofos , Humanos , Neoplasias Hipofisárias/patologia , Acromegalia/metabolismo , Somatotrofos/metabolismo , Somatotrofos/patologia , Hibridização Genômica Comparativa , Hiperplasia/patologia , Estudos de Coortes , Genótipo , Adenoma Hipofisário Secretor de Hormônio do Crescimento/metabolismo , Adenoma/patologia , Hormônio do Crescimento Humano/metabolismo , Hormônio do Crescimento/metabolismo , Glucose , Histona Desmetilases/genética , Histona Desmetilases/metabolismo
9.
Expert Rev Endocrinol Metab ; 18(2): 181-198, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36876325

RESUMO

INTRODUCTION: Pituitary adenomas can show a tendency to grow, despite multimodal treatment. Temozolomide (TMZ) has been used in the last 15 years in patients with aggressive pituitary tumors. TMZ requires a careful balance of different expertise, especially for selection criteria. AREAS COVERED: We conducted: (1) a systematic review of the published literature from 2006 to 2022, collecting only cases with a complete description of patient follow-up after TMZ discontinuation; (2) a description of all patients with aggressive pituitary adenoma or carcinoma treated in Padua (Italy). EXPERT OPINION: There is considerable heterogeneity in the literature: TMZ cycles duration ranged from 3 to 47 months; the follow-up time after TMZ discontinuation ranged from 4 to 91 months (mean 24 months, median 18 months), at least a stable disease has been reported in 75% of patients after a mean 13 months (range 3-47 months, median 10 months). The Padua (Italy) cohort reflects the literature. Future directions to explore are to understand the pathophysiological mechanism of TMZ resistance escape, to develop predicting factors to TMZ treatment (especially through the delineation of the underlying transformation processes), and to further expand the therapeutic applications of TMZ (as neoadjuvant, combined with radiotherapy).


Assuntos
Adenoma , Carcinoma , Neoplasias Hipofisárias , Humanos , Temozolomida/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/patologia , Antineoplásicos Alquilantes/uso terapêutico , Dacarbazina/uso terapêutico , Adenoma/tratamento farmacológico , Adenoma/patologia , Carcinoma/tratamento farmacológico , Carcinoma/patologia
10.
Endocr Relat Cancer ; 29(5): 273-284, 2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35298396

RESUMO

The improper expression of glucose-dependent insulinotropic polypeptide receptor (GIPR) and the GIP/GIPR axis activation has been increasingly recognized in endocrine tumors, with a potential diagnostic and prognostic value. A high tumor-to-normal tissue ratio (T/N ratio) of GIPR was reported both in humans' and in rats' medullary thyroid cancer (MTC), suggesting a direct link between the neoplastic transformation and the mechanism of receptor overexpression. In this study, we evaluated the potential diagnostic and prognostic significance of GIPR expression in a large cohort of MTC patients by correlating GIPR mRNA steady-state levels to clinical phenotypes. The molecular effect of GIP/GIPR axis stimulation in MTC-derived cells was also determined. We detected GIPR expression in ~80% of tumor specimens, especially in sporadic, larger, advanced-stage cancers with higher Ki-67 values. GIPR stimulation induced cAMP elevation in MTC-derived cells and a small but significant fluctuation in Ca2+, both likely associated with increased calcitonin secretion. On the contrary, the effects on PI3K-Akt and MAPK-ERK1/2 signaling pathways were marginal. To conclude, our data confirm the high T/N GIPR ratio in MTC tumors and suggest that it may represent an index for the degree of advancement of the malignant process. We have also observed a functional coupling between GIP/GIPR axis and calcitonin secretion in MTC models. However, the molecular mechanisms underlying this process and the possible implication of GIP/GIPR axis activation in MTC diagnosis and prognosis need further evaluation.


Assuntos
Polipeptídeo Inibidor Gástrico , Neoplasias da Glândula Tireoide , Calcitonina , Carcinoma Neuroendócrino , Polipeptídeo Inibidor Gástrico/genética , Polipeptídeo Inibidor Gástrico/metabolismo , Polipeptídeo Inibidor Gástrico/farmacologia , Humanos , Fosfatidilinositol 3-Quinases , Receptores dos Hormônios Gastrointestinais , Neoplasias da Glândula Tireoide/genética
11.
Neuroendocrinology ; 93(2): 121-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21304226

RESUMO

BACKGROUND: Hypercoagulability and a tendency for thromboembolic complications are reported in Cushing's syndrome (CS). The hypercoagulability is due mainly to the cortisol-induced increase in von Willebrand factor (VWF) and factor VIII. This is not a constant feature of CS, however; it depends on particular single nucleotide polymorphism (SNP) haplotypes in the VWF gene promoter: haplotype 1 (-3268G/-2709C/-2661A/-2527G) confers a greater risk of VWF upregulation by cortisol than haplotype 2 (-3268C/ -2709T/-2661G/-2527A). In healthy individuals these SNPs are in linkage disequilibrium with the -2144 (GT)(n) of the VWF promoter: haplotype 1 mainly segregates with short GT repeats (15-19, GTs), haplotype 2 with long repeats (GT ≥ 20, GT(L)). METHODS: We analyzed the (GT)(n) locus, the SNP haplotypes and their association with VWF levels in 80 CS patients in order to precisely define the cortisol-sensitive VWF promoter pattern. CS patients were divided into groups A (increased VWF) and B (normal VWF). RESULTS: Haplotype 1 and (GT)(S) were more frequent in group A patients, and conferred a 9- and 7.5-fold risk of developing high VWF levels, respectively. Haplotype 2 and (GT)(L) were more represented in group B. There was also an unexpected higher prevalence of recombinant SNP haplotypes in CS patients (6.2%) than in normals (0.9%), p = 0.002. CONCLUSIONS: Our results indicate that the cortisol-induced increase in VWF may be predicted by VWF promoter polymorphisms, haplotype 1 and (GT)(S) being the sensitive pattern. These represent new markers for defining the prothrombotic risk of CS. The clinical significance, if any, of the increased recombination rate in SNP haplotypes in the VWF promoter warrants further study.


Assuntos
Síndrome de Cushing/genética , Síndrome de Cushing/metabolismo , Trombofilia/genética , Trombofilia/metabolismo , Adulto , Síndrome de Cushing/urina , Feminino , Haplótipos , Humanos , Hidrocortisona/urina , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo
12.
Hormones (Athens) ; 20(1): 143-150, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32840821

RESUMO

BACKGROUND AND AIM: Acromegaly is a rare disease with a peak of incidence in early adulthood. However, enhanced awareness of this disease, combined with wide availability of magnetic resonance imaging (MRI), has increased the diagnosis of forms with mild presentation, especially in elderly patients. Moreover, due to increased life expectancy and proactive individualized treatment, patients with early-onset acromegaly are today aging. The aim of our study was to describe our cohort of elderly patients with acromegaly. MATERIALS AND METHODS: This is a cross-sectional retrospective study of 96 outpatients. Clinical, endocrine, treatment, and follow-up data were collected using the electronic database of the University Hospital of Padova, Italy. RESULTS: We diagnosed acromegaly in 13 patients, aged ≥65 years, presenting with relatively small adenomas and low IGF-1 secretion. Among them, 11 patients were initially treated with medical therapy and half normalized hormonal levels after 6 months without undergoing neurosurgery (TNS). Remission was achieved after TNS in three out of four patients (primary TNS in two); ten patients presented controlled acromegaly at the last visit. Acromegaly-related comorbidities (colon polyps, thyroid cancer, adrenal incidentaloma, hypertension, and bone disease) were more prevalent in patients who had an early diagnosis (31 patients, characterized by a longer follow-up of 24 years) than in those diagnosed aged ≥65 years (5 years of follow-up). CONCLUSIONS: Elderly acromegalic patients are not uncommon. Primary medical therapy is a reasonable option and is effectively used, while the rate of surgical success is not reduced. A careful cost-benefit balance is suggested. Disease-specific comorbidities are more prevalent in acromegalic patients with a longer follow-up rather than in those diagnosed aged ≥65 years.


Assuntos
Acromegalia/diagnóstico , Acromegalia/terapia , Adenoma/diagnóstico , Neoplasias Hipofisárias/complicações , Adenoma/terapia , Idoso , Estudos Transversais , Humanos , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/terapia , Estudos Retrospectivos
13.
Artigo em Inglês | MEDLINE | ID: mdl-32117062

RESUMO

Objective: Germline ARMC5 mutations are considered to be the main genetic cause of primary macronodular adrenal hyperplasia (PMAH). PMAH is associated with high variability of cortisol secretion caused from subclinical hypercortisolism to overt Cushing's syndrome (CS), in general due to bilateral adrenal nodules and rarely could also be due to non-synchronic unilateral adrenal nodules. The frequency of adrenal incidentalomas (AI) associated with PMAH is unknown. This study evaluated germline allelic variants of ARMC5 in patients with bilateral and unilateral AI and in patients with overt CS associated with bilateral adrenal nodules. Methods: We performed a retrospective multicenter study involving 123 patients with AI (64 bilateral; 59 unilateral). We also analyzed 20 patients with ACTH pituitary independent overt CS associated with bilateral adrenal nodules. All patients underwent germline genotyping analysis of ARMC5; abdominal CT and were classified as normal, possible or autonomous cortisol secretion, according to the low doses of dexamethasone suppression test. Results: We identified only one pathogenic allelic variant among the patients with bilateral AI. We did not identify any pathogenic allelic variants of ARMC5 in patients with unilateral AI. Thirteen out of 20 patients (65%) with overt CS and bilateral adrenal nodules were carriers of pathogenic germline ARMC5 allelic variants, all previously described. The germline ARMC5 mutation was observed in only one patient with bilateral AI; it was associated with autonomous cortisol secretion and showed to be a familial form. Conclusion: The rarity of germline ARMC5 mutations in AI points to other molecular mechanisms involved in this common adrenal disorder and should be investigated. In contrast, patients with overt Cushing's syndrome and bilateral adrenal nodules had the presence of ARMC5 mutations that were with high prevalence and similar to the literature. Therefore, we recommend the genetic analysis of ARMC5 for patients with established Cushing's syndrome and bilateral adrenal nodules rather than patients with unilateral AI.


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Proteínas do Domínio Armadillo/genética , Síndrome de Cushing/genética , Polimorfismo de Nucleotídeo Único , Doenças das Glândulas Suprarrenais/epidemiologia , Doenças das Glândulas Suprarrenais/etiologia , Doenças das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/epidemiologia , Adulto , Alelos , Estudos de Casos e Controles , Síndrome de Cushing/complicações , Síndrome de Cushing/epidemiologia , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
Forensic Sci Int Genet ; 40: 192-200, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30884346

RESUMO

Forensic DNA phenotyping (FDP) has recently provided important advancements in forensic investigations, by predicting the physical appearance of a subject from a biological sample, using SNP markers. The majority of operable prediction models have been developed for iris color; however, replication studies to understand their applicability on a worldwide scale are still limited for many of them. In this work, 4 models for eye color prediction (IrisPlex, Ruiz, Allwood and Hart models) were systematically evaluated in a sample of 296 subjects of Italian origin. Genotypes were determined by a custom NGS-based panel targeting all the predictive SNPs included in the 4 tested models. Overall, 60-69% of the Italian sample could be correctly predicted with the IrisPlex, Ruiz and Allwood models, applying the recommended threshold. The IrisPlex model showed the lowest frequency of errors (17%), but also the highest number of inconclusive results (18%). In the absence of the threshold, the highest proportion of correct predictions was again obtained with the IrisPlex model (76%), followed by the Allwood (73%) and the Ruiz (65%) models. Lastly, the Hart predictive algorithm had the lowest error rate (2%), but the majority of predictions (87%) were restricted to the less informative categories of "not-blue" and "not-brown", and correct color predictions were obtained only for 11% of the sample. As observed in previous studies, the majority of incorrect and undefined predictions were ascribable to the intermediate category, which represented 25% of the Italian sample. An adjustment of the IrisPlex (multinomial logistic regression) and Ruiz models (Snipper Bayesian classifier) with Italian allele frequencies gave only minor improvements in predicting intermediate eye color and no remarkable overall changes in performance. This suggests an incomplete knowledge underlying the intermediate colors. Considering the impact of this phenotype in the Italian sample as well as in other admixed populations, future improvements of eye color prediction methods should include a better genetic and phenotypic characterization of this category.


Assuntos
Cor de Olho/genética , Modelos Genéticos , Algoritmos , Árvores de Decisões , Feminino , Genótipo , Técnicas de Genotipagem/instrumentação , Humanos , Itália , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/métodos
15.
J Clin Endocrinol Metab ; 104(3): 856-862, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30285115

RESUMO

Context: The oral glucose tolerance test (OGTT) is considered the most useful method for diagnosing active acromegaly and for patient follow-up after neurosurgery. Despite its widespread use, only a few small studies have so far focused on patients' clinical features associated with different GH responsiveness to OGTT. Objective: We aimed to investigate the association between glucose-induced GH response and endocrine profiles, clinical manifestations, and response to therapy in a large cohort of patients with acromegaly. Patients: According to GH response to OGTT, patients were grouped as paradoxical (GH-Par) or nonparadoxical (GH-NPar), and their clinical and pathological features were compared in terms of pituitary tumor size, invasiveness, biochemical profiles, and response to therapy. Results: The study concerned 496 patients with acromegaly. At diagnosis, those with GH-Par (n = 184) were older than those with GH-NPar (n = 312) (mean ± SD, 44.1 ± 13.7 years vs 40.5 ± 12.7 years; P < 0.01) and had smaller tumors (0.82 vs 1.57 cm3; P < 0.01) that less frequently invaded the cavernous sinus (15% vs 27%; P < 0.01). The GH-Par group also had a higher basal GH per volume ratio (14.3 vs 10.5 µg/L ⋅ cm3; P < 0.05) and a lower incidence of hyperprolactinemia (17% vs 30%; P < 0.01) than the GH-NPar group. Importantly, the GH-Par group had a higher rate of remission in response to somatostatin analogues (52% vs 26%; P < 0.01) and a more marked drop in IGF-1 and GH after 6 months of therapy. Conclusions: Our data strongly suggest that serum GH responsiveness to oral glucose challenge reflects some important biological features of pituitary tumors and that the OGTT may have some prognostic value.


Assuntos
Acromegalia/terapia , Adenoma/terapia , Adenoma Hipofisário Secretor de Hormônio do Crescimento/terapia , Hormônio do Crescimento Humano/sangue , Somatostatina/administração & dosagem , Acromegalia/sangue , Acromegalia/etiologia , Adenoma/complicações , Administração Oral , Adulto , Feminino , Glucose/administração & dosagem , Teste de Tolerância a Glucose , Adenoma Hipofisário Secretor de Hormônio do Crescimento/complicações , Hormônio do Crescimento Humano/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Hipófise/cirurgia , Prognóstico , Somatostatina/análogos & derivados , Resultado do Tratamento
16.
Heart Rhythm ; 16(5): 773-780, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30453078

RESUMO

BACKGROUND: Arrhythmogenic cardiomyopathy (ACM) is associated with arrhythmias and risk of sudden death. Mutations in genes encoding proteins of cardiac intercalated discs account for ∼60% of ACM cases, but the remaining 40% is still genetically elusive. OBJECTIVE: The purpose of this study was to identify the underlying genetic cause in probands with ACM. METHODS: DNA samples from 40 probands with ACM, negative for mutations in the 3 major ACM genes-DSP, PKP2, and DSG2, were screened by using a targeted gene panel consisting of 15 known ACM genes and 53 candidate genes. RESULTS: About half of patients were found to carry rare variant(s) predicted to be damaging; specifically, 9 (22.5%) showed ≥1 variants in genes associated with ACM and/or with other inherited heart diseases and 10 (25%) showed variants in candidate genes. Among the latter, we focused on 2 novel variants in TP63 and PPP1R13L candidate genes (c.796C>T, p.(R266*) and c.1858G>C, p.(A620P), respectively). The encoded proteins p63 and inhibitor of apoptosis stimulating p53 protein are known to be interacting partners. Inhibitor of apoptosis stimulating p53 protein is a shuttling multifunctional protein: in the nucleus it is critical for inhibiting p63 function, whereas in the cytoplasm it regulates desmosome integrity. According to the American College of Medical Genetics and Genomics guidelines, the variant in TP63 has been scored as likely pathogenic and the variant in PPP1R13L as a variant of uncertain significance. Importantly, the mutant TP63 allele leads to nonsense-mediated messenger RNA decay, causing haploinsufficiency. CONCLUSION: Our findings identify TP63 as a putative novel disease gene for ACM, while the possible involvement of PPP1R13L remains to be determined.


Assuntos
Displasia Arritmogênica Ventricular Direita/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Adulto , Proteínas Reguladoras de Apoptose/genética , Códon sem Sentido , Desmossomos/genética , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas Repressoras/genética
17.
Neuromuscul Disord ; 18(8): 597-605, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18602263

RESUMO

Antisense-mediated exon skipping holds great potential for the treatment of DMD. In mdx mice, functional recovery of skeletal muscle has been obtained upon systemic delivery of "naked" oligonucleotides or viral vectors encoding for antisense snRNAs. However, amongst the studies reported so far, which used either neonatal or young adult animals--only one achieved dystrophin restoration in cardiac muscle, using an adeno-associated vector. Here we report the in vivo delivery of morpholino oligos in aged mdx mice, both in skeletal muscle, via intra-arterial injection, and in cardiac muscle, via intra-muscular injection. Localized intra-arterial delivery yielded high levels of dystrophin restoration and just two doses of 100 microg each resulted into detectable force recovery in the EDL muscles of treated limbs. On the other hand, upon intra-cardiac injections in the left ventricle wall the skipping effect was much lower than what obtained in tibialis anterior muscles injected with comparable amounts of oligos. This latter finding suggests that even upon direct delivery antisense-mediated dystrophin restoration in cardiac muscle might suffer from limitations that do not exist in skeletal muscle.


Assuntos
Distrofina/biossíntese , Distrofina/genética , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Envelhecimento/fisiologia , Animais , Western Blotting , Interpretação Estatística de Dados , Éxons/genética , Coração/efeitos dos fármacos , Coração/fisiologia , Ventrículos do Coração/efeitos dos fármacos , Imuno-Histoquímica , Injeções Intra-Arteriais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Contração Muscular/fisiologia , Músculo Esquelético/fisiopatologia , Oligonucleotídeos Antissenso/administração & dosagem , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Artigo em Inglês | MEDLINE | ID: mdl-30159145

RESUMO

Tuberous sclerosis complex (TSC) is an autosomal dominant multisystem hereditary cutaneous condition, characterized by multiple hamartomas. In rare cases, pituitary neuroendocrine tumors (PitNETs) have been described in patients with TSC, but the causal relationship between these two diseases is still under debate. TSC is mostly caused by mutations of two tumor suppressor genes, encoding for hamartin (TSC1) and tuberin (TSC2), controlling cell growth and proliferation. Here, we present the case of a 62-year-old Caucasian woman with TSC and a silent gonadotroph PitNET with suprasellar extension, treated with transsphenoidal endoscopic neurosurgery with complete resection. Therapeutic approaches based on mTOR signaling (i.e. everolimus) have been successfully used in patients with TSC and tested in non-functioning PitNET cellular models with promising results. Here, we observed a reduction of cell viability after an in vitro treatment of PitNET's derived primary cells with everolimus. TSC analysis retrieved no disease-associated variants with the exception of the heterozygous intronic variant c.4006-71C>T found in TSC2: the computational tools predicted a gain of a new splice site with consequent intron retention, not confirmed by an in vitro analysis of patient's lymphocyte-derived RNA. Further analyses are therefore needed to provide insights on the possible mechanisms involving the hamartin-tuberin complex in the pathogenesis of pituitary adenomas. However, our data further support previous observations of an antiproliferative effect of everolimus on PitNET. LEARNING POINTS: Pituitary neuroendocrine tumors (PitNET) in patients with tuberous sclerosis complex (TSC) are rare: only few cases have been reported in literature.Therapeutic approach related to mTOR signaling, such as everolimus, may be used in some patients with PitNETs as well as those with TSC.We reported a woman with both non-secreting PitNET and TSC; PitNET was surgically removed and classified as a silent gonadotroph tumor.Everolimus treatment in PitNET's-derived primary cells revealed a significant decrease in cell viability.Considering our case and available evidence, it is still unclear whether a PitNET is a part of TSC or just a coincidental tumor.

19.
BMC Med Genet ; 8: 65, 2007 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-17963498

RESUMO

BACKGROUND: Mutations in genes encoding desmosomal proteins have been reported to cause arrhythmogenic right ventricular cardiomyopathy (ARVC), an autosomal dominant disease characterised by progressive myocardial atrophy with fibro-fatty replacement. We screened 54 ARVC probands for mutations in desmocollin-2 (DSC2), the only desmocollin isoform expressed in cardiac tissue. METHODS: Mutation screening was performed by denaturing high-performance liquid chromatography and direct sequencing. To evaluate the pathogenic potentials of the DSC2 mutations detected in patients affected with ARVC, full-length wild-type and mutated cDNAs were cloned in eukaryotic expression vectors to obtain a fusion protein with green fluorescence protein (GFP); constructs were transfected in neonatal rat cardiomyocytes and in HL-1 cells. RESULTS: We identified two heterozygous mutations (c.304G>A (p.E102K) and c.1034T>C (p.I345T)) in two probands and in four family members. The two mutations p.E102K and p.I345T map to the N-terminal region, relevant to adhesive interactions. In vitro functional studies demonstrated that, unlike wild-type DSC2, the two N-terminal mutants are predominantly localised in the cytoplasm. CONCLUSION: The two missense mutations in the N-terminal domain affect the normal localisation of DSC2, thus suggesting the potential pathogenic effect of the reported mutations. Identification of additional DSC2 mutations associated with ARVC may result in increased diagnostic accuracy with implications for genetic counseling.


Assuntos
Displasia Arritmogênica Ventricular Direita/genética , Desmocolinas/genética , Mutação de Sentido Incorreto , Adolescente , Adulto , Animais , Células Cultivadas , Feminino , Triagem de Portadores Genéticos , Proteínas de Fluorescência Verde , Humanos , Masculino , Pessoa de Meia-Idade , Miócitos Cardíacos , Ratos , Transfecção
20.
Artigo em Inglês | MEDLINE | ID: mdl-29038103

RESUMO

BACKGROUND: Arrhythmogenic cardiomyopathy (AC) is an inherited heart muscle disease associated with point mutations in genes encoding for cardiac desmosome proteins. Conventional mutation screening is positive in ≈50% of probands. Copy number variations (CNVs) have recently been linked to AC pointing to the need to determine the prevalence of CNVs in desmosomal genes and to evaluate disease penetrance by cosegregation analysis in family members. METHODS AND RESULTS: A total of 160 AC genotype-negative probands for 5 AC desmosomal genes by conventional mutation screening underwent multiplex ligation-dependent probe amplification. Nine heterozygous CNVs were identified in 11 (6.9%) of the 160 probands. Five carried a deletion of the entire plakophilin-2 (PKP2) gene, 2 a deletion of only PKP2 exon 4, 1 a deletion of the PKP2 exons 6 to 11, 1 a PKP2 duplication of 5' untranslated region till exon 1, 1 the desmocollin-2 (DSC2) duplication of exons 7 to 9, and 1 a large deletion of chromosome 18 comprising both DSC2 and desmoglein-2 genes. All probands were affected by moderate-severe forms of the disease, whereas 10 (32%) of the 31 family members carrying one of these deletions fulfilled the diagnostic criteria. CONCLUSIONS: Genomic rearrangements were detected in ≈7% of AC probands negative for pathogenic point mutations in desmosomal genes, highlighting the potential of CNVs analysis to substantially increase the diagnostic yield of genetic testing. Genotype-phenotype correlation demonstrated the presence of the disease in about one third of family members carrying the CNV, underlying the role of other factors in the development and progression of the disease.


Assuntos
Displasia Arritmogênica Ventricular Direita/genética , Desmossomos/genética , Rearranjo Gênico , Potenciais de Ação , Adolescente , Adulto , Idoso , Displasia Arritmogênica Ventricular Direita/diagnóstico , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Desmocolinas/genética , Desmogleína 2/genética , Desmoplaquinas/genética , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Feminino , Deleção de Genes , Dosagem de Genes , Duplicação Gênica , Estudos de Associação Genética , Marcadores Genéticos , Predisposição Genética para Doença , Frequência Cardíaca , Hereditariedade , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Linhagem , Fenótipo , Placofilinas/genética , Mutação Puntual , Fatores de Risco , Adulto Jovem , gama Catenina
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