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1.
EMBO J ; 40(13): e106777, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33999432

RESUMO

The p14ARF protein is a well-known regulator of p53-dependent and p53-independent tumor-suppressive activities. In unstressed cells, p14ARF is predominantly sequestered in the nucleoli, bound to its nucleolar interaction partner NPM. Upon genotoxic stress, p14ARF undergoes an immediate redistribution to the nucleo- and cytoplasm, where it promotes activation of cell cycle arrest and apoptosis. Here, we identify p14ARF as a novel interaction partner and substrate of PRMT1 (protein arginine methyltransferase 1). PRMT1 methylates several arginine residues in the C-terminal nuclear/nucleolar localization sequence (NLS/NoLS) of p14ARF . In the absence of cellular stress, these arginines are crucial for nucleolar localization of p14ARF . Genotoxic stress causes augmented interaction between PRMT1 and p14ARF , accompanied by arginine methylation of p14ARF . PRMT1-dependent NLS/NoLS methylation promotes the release of p14ARF from NPM and nucleolar sequestration, subsequently leading to p53-independent apoptosis. This PRMT1-p14ARF cooperation is cancer-relevant and indicative for PDAC (pancreatic ductal adenocarcinoma) prognosis and chemotherapy response of pancreatic tumor cells. Our data reveal that PRMT1-mediated arginine methylation is an important trigger for p14ARF 's stress-induced tumor-suppressive function.


Assuntos
Neoplasias Pancreáticas/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo , Proteína Supressora de Tumor p14ARF/metabolismo , Animais , Apoptose/fisiologia , Ciclo Celular/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , Células HEK293 , Células HeLa , Humanos , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias Pancreáticas/patologia , Prognóstico , Células Sf9 , Proteína Supressora de Tumor p53/metabolismo , Neoplasias Pancreáticas
2.
Hum Hered ; 89(1): 8-31, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38198765

RESUMO

INTRODUCTION: Joint linkage and association (JLA) analysis combines two disease gene mapping strategies: linkage information contained in families and association information contained in populations. Such a JLA analysis can increase mapping power, especially when the evidence for both linkage and association is low to moderate. Similarly, an association analysis based on haplotypes instead of single markers can increase mapping power when the association pattern is complex. METHODS: In this paper, we present an extension to the GENEHUNTER-MODSCORE software package that enables a JLA analysis based on haplotypes and uses information from arbitrary pedigree types and unrelated individuals. Our new JLA method is an extension of the MOD score approach for linkage analysis, which allows the estimation of trait-model and linkage disequilibrium (LD) parameters, i.e., penetrance, disease-allele frequency, and haplotype frequencies. LD is modeled between alleles at a single diallelic disease locus and up to three diallelic test markers. Linkage information is contributed by additional multi-allelic flanking markers. We investigated the statistical properties of our JLA implementation using extensive simulations, and we compared our approach to another commonly used single-marker JLA test. To demonstrate the applicability of our new method in practice, we analyzed pedigree data from the German National Case Collection for Familial Pancreatic Cancer (FaPaCa). RESULTS: Based on the simulated data, we demonstrated the validity of our JLA-MOD score analysis implementation and identified scenarios in which haplotype-based tests outperformed the single-marker test. The estimated trait-model and LD parameters were in good accordance with the simulated values. Our method outperformed another commonly used JLA single-marker test when the LD pattern was complex. The exploratory analysis of the FaPaCa families led to the identification of a promising genetic region on chromosome 22q13.33, which can serve as a starting point for future mutation analysis and molecular research in pancreatic cancer. CONCLUSION: Our newly proposed JLA-MOD score method proves to be a valuable gene mapping and characterization tool, especially when either linkage or association information alone provide insufficient power to identify the disease-causing genetic variants.


Assuntos
Carcinoma , Ligação Genética , Haplótipos , Desequilíbrio de Ligação , Neoplasias Pancreáticas , Software , Humanos , Neoplasias Pancreáticas/genética , Haplótipos/genética , Linhagem , Modelos Genéticos , Feminino , Masculino , Predisposição Genética para Doença , Simulação por Computador , Frequência do Gene/genética , Polimorfismo de Nucleotídeo Único/genética , Mapeamento Cromossômico/métodos
3.
Cardiol Young ; : 1-6, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35232516

RESUMO

The timing of pulmonary valve replacement in patients with pulmonary regurgitation following treatment of pulmonary stenosis is undefined. Although cardiac magnetic resonance-based right ventricular volumes in tetralogy of Fallot patients have been used as a guide in pulmonary stenosis patients, anatomic differences between tetralogy of Fallot and pulmonary stenosis patients complicate their application to pulmonary stenosis patients and could result in late referral for pulmonary valve replacement. We sought to determine if pulmonary stenosis patients referred for pulmonary valve replacement were at greater risk for morbidity or need for tricuspid valve intervention at the time of pulmonary valve replacement. A retrospective cohort study was performed on all adult patients with a diagnosis of pulmonary stenosis or tetralogy of Fallot followed at our centre. Clinical and imaging-based exposures were collected. Pre-specified endpoints included need for concomitant tricuspid valve repair or replacement and pre- and post-pulmonary valve replacement cardiac magnetic resonance-based volumetric measurements. Between 1/1999 and 1/2020, 235 patients underwent pulmonary valve replacement for pulmonary regurgitation (52 with pulmonary stenosis, 183 with tetralogy of Fallot). Pulmonary stenosis patients were more likely to have at least moderate tricuspid regurgitation (p = 0.010), undergo concomitant tricuspid valve intervention (p = 0.003), and require tricuspid valve repair or replacement secondary to annular dilation (p = 0.027) compared to tetralogy of Fallot patients. There was no difference in pre-pulmonary valve replacement right ventricular size between pulmonary stenosis and tetralogy of Fallot patients. These findings suggest that referral for pulmonary valve replacement may be occurring later in the disease course for pulmonary stenosis patients.

4.
Int J Mol Sci ; 23(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35216088

RESUMO

The metalloprotease-disintegrin ADAM8 is critically involved in the progression of pancreatic cancer. Under malignant conditions, ADAM8 is highly expressed and could play an important role in cell-cell communication as expression has been observed in tumor and immune cells of the tumor microenvironment (TME) such as macrophages. To analyze the potential role of ADAM8 in the TME, ADAM8 knockout PDAC tumor cells were generated, and their release of extracellular vesicles (EVs) was analyzed. In EVs, ADAM8 is present as an active protease and associated with lipocalin 2 (LCN2) and matrix metalloprotease 9 (MMP-9) in an ADAM8-dependent manner, as ADAM8 KO cells show a lower abundance of LCN2 and MMP-9. Sorting of ADAM8 occurs independent of TSG101, even though ADAM8 contains the recognition motif PTAP for the ESCRTI protein TSG101 within the cytoplasmic domain (CD). When tumor cells were co-cultured with macrophages (THP-1 cells), expression of LCN2 and MMP-9 in ADAM8 KO cells was induced, suggesting that macrophage signaling can overcome ADAM8-dependent intracellular signaling in PDAC cells. In co-culture with macrophages, regulation of MMP-9 is independent of the M1/M2 polarization state, whereas LCN2 expression is preferentially affected by M1-like macrophages. From these data, we conclude that ADAM8 has a systemic effect in the tumor microenvironment, and its expression in distinct cell types has to be considered for ADAM8 targeting in tumors.


Assuntos
Proteínas ADAM/metabolismo , Lipocalina-2/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteínas de Membrana/metabolismo , Transdução de Sinais/fisiologia , Microambiente Tumoral/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Vesículas Extracelulares/metabolismo , Humanos , Macrófagos/metabolismo , Neoplasias Pancreáticas/metabolismo , Células THP-1
5.
N Engl J Med ; 388(22): 2087-2093, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37256979

Assuntos
Erros Médicos , Humanos
6.
Int J Mol Sci ; 21(19)2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33022971

RESUMO

The biology of solid tumors is strongly determined by the interactions of cancer cells with their surrounding microenvironment. In this regard, pancreatic cancer (pancreatic ductal adenocarcinoma, PDAC) represents a paradigmatic example for the multitude of possible tumor-stroma interactions. PDAC has proven particularly refractory to novel immunotherapies, which is a fact that is mediated by a unique assemblage of various immune cells creating a strongly immunosuppressive environment in which this cancer type thrives. In this review, we outline currently available knowledge on the cross-talk between tumor cells and the cellular immune microenvironment, highlighting the physiological and pathological cellular interactions, as well as the resulting therapeutic approaches derived thereof. Hopefully a better understanding of the complex tumor-stroma interactions will one day lead to a significant advancement in patient care.


Assuntos
Adenocarcinoma/imunologia , Carcinoma Ductal Pancreático/imunologia , Microambiente Tumoral/imunologia , Adenocarcinoma/patologia , Carcinoma Ductal Pancreático/patologia , Humanos , Imunoterapia
7.
Clin Sci (Lond) ; 133(1): 83-99, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30635388

RESUMO

Ectodomain shedding of extracellular and membrane proteins is of fundamental importance for cell-cell communication in neoplasias. A Disintegrin And Metalloproteinase (ADAM) proteases constitute a family of multifunctional, membrane-bound proteins with traditional sheddase functions. Their protumorigenic potential has been attributed to both, essential (ADAM10 and ADAM17) and 'dispensable' ADAM proteases (ADAM8, 9, 12, 15, and 19). Of specific interest in this review is the ADAM proteinase ADAM8 that has been identified as a significant player in aggressive malignancies including breast, pancreatic, and brain cancer. High expression levels of ADAM8 are associated with invasiveness and predict a poor patient outcome, indicating a prognostic and diagnostic potential of ADAM8. Current knowledge of substrates and interaction partners gave rise to the hypothesis that ADAM8 dysregulation affects diverse processes in tumor biology, attributable to different functional cores of the multidomain enzyme. Proteolytic degradation of extracellular matrix (ECM) components, cleavage of cell surface proteins, and subsequent release of soluble ectodomains promote cancer progression via induction of angiogenesis and metastasis. Moreover, there is increasing evidence for significance of a non-proteolytic function of ADAM8. With the disintegrin (DIS) domain ADAM8 binds integrins such as ß1 integrin, thereby activating integrin signaling pathways. The cytoplasmic domain is critical for that activation and involves focal adhesion kinase (FAK), extracellular regulated kinase (ERK1/2), and protein kinase B (AKT/PKB) signaling, further contributing to cancer progression and mediating chemoresistance against first-line therapies. This review highlights the remarkable effects of ADAM8 in tumor biology, concluding that pharmacological inhibition of ADAM8 represents a promising therapeutic approach not only for monotherapy, but also for combinatorial therapies.


Assuntos
Proteínas ADAM/metabolismo , Biomarcadores Tumorais/metabolismo , Movimento Celular , Resistencia a Medicamentos Antineoplásicos , Proteínas de Membrana/metabolismo , Neoplasias/enzimologia , Proteínas ADAM/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Progressão da Doença , Humanos , Proteínas de Membrana/antagonistas & inibidores , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Inibidores de Proteases/uso terapêutico , Proteólise , Transdução de Sinais , Especificidade por Substrato
8.
World J Surg ; 43(3): 831-838, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30600364

RESUMO

OBJECTIVE: Long-acting synthetic somatostatin analogues (SSA) are an essential part of the treatment of neuroendocrine neoplasms. We evaluated the chemopreventive effects of a long-acting somatostatin analogue on the development of pancreatic neuroendocrine neoplasms (pNENs) in a genetically engineered MEN1 knockout mouse model. MATERIALS AND METHODS: Heterozygote MEN1 knockout mice were injected every 28 days subcutaneously with the somatostatin analogue lanreotide (Somatuline Autogel©; Ipsen Pharma) or a placebo starting at day 35 after birth. Mice were euthanized after 6, 9, 12, 15 and 18 months, and the size and number of pNENs were measured due histological analysis and compared to the placebo group. RESULTS: The median tumor size of pNENs was statistically significantly smaller after 9 (control group vs. SSA group; 706.476 µm2 vs. 195.271 µm2; p = 0.0012), 12 (placebo group vs. SSA group 822.022 vs. 255.482; p ≤ 0.001), 15 (placebo group vs. SSA group 1192.568 vs. 273.533; p ≤ 0.001) and after 18 months (placebo group vs. SSA group 1328.299 vs. 864.587; p ≤ 0.001) in the SSA group. Comparing the amount of tumors in both groups, a significant reduction was achieved in treated Men1(+/-) mice (41%, p = 0.002). Immunostaining showed, however, no significant difference in the expression of the apoptosis marker caspase-3, but a significant difference in Ki67 index as a marker for tumor cell proliferation (p ≤ 0.005). CONCLUSION: Long-acting somatostatin analogues may be an effective chemopreventive approach to delay the progression of MEN1-associated pNENs. After our preclinical results, we would recommend to evaluate the effects of long-acting SSA in a prospective clinical trial.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasia Endócrina Múltipla Tipo 1/prevenção & controle , Tumores Neuroendócrinos/prevenção & controle , Neoplasias Pancreáticas/prevenção & controle , Peptídeos Cíclicos/uso terapêutico , Somatostatina/análogos & derivados , Animais , Caspase 3/metabolismo , Proliferação de Células , Quimioprevenção , Modelos Animais de Doenças , Progressão da Doença , Antígeno Ki-67/metabolismo , Camundongos , Camundongos Knockout , Neoplasia Endócrina Múltipla Tipo 1/metabolismo , Neoplasia Endócrina Múltipla Tipo 1/patologia , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas/genética , Somatostatina/uso terapêutico , Carga Tumoral
9.
Neuroendocrinology ; 106(4): 312-317, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28848144

RESUMO

BACKGROUND/AIMS: Neuroendocrine neoplasms of the small intestine (SI-NENs) constitute 25-30% of all gastroenteropancreatic NEN. These tumors arise from enterochromaffin cells, and little is known about their microRNA (miRNA) expression. The purpose of this study was to characterize the expression of miRNAs in SI-NEN and to determine the potential of miRNAs as noninvasive blood-based biomarkers. METHODS: miRNA was purified from 15 tumor and 7 control tissue samples, converted to cDNA, and applied to a miScript miRNA PCR. The small nucleolar RNA, SNORD95, was used as an endogenous control. RESULTS: Microarray analysis revealed 7 miRNAs that showed a promising distinction between tumorous and healthy tissue. The miRNAs miR-7-5p and miR-96-5p were clearly upregulated in the tumor compared to the healthy tissue. In contrast, miRNAs miR-9-5p, miR-122-5p, miR-124-3p, miR-143-3p, and miR-144-3p showed a distinct downregulation in the tumor compared to the healthy tissue. These results were validated on a further 15 tumor samples, and the findings held true. As the miR-7-5p was significantly upregulated and revealed a low range across tumor samples, its presence was tested in the sera of 32 tumor patients and 25 healthy controls. Sera from all patients with SI-NENs had significantly higher levels of miR-7-5p than those from the 25 healthy controls (p = 0.0002), whereas there was no correlation with age, gender, or T-stage or UICC stage. CONCLUSION: The miRNA miR-7-5p may be a promising biomarker test for SI-NEN, which should be validated in a large-scale prospective study.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Intestinais/patologia , MicroRNAs/biossíntese , Tumores Neuroendócrinos/patologia , Adulto , Idoso , Biomarcadores Tumorais/análise , Feminino , Humanos , Neoplasias Intestinais/genética , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/genética , Regulação para Cima
10.
Neuroendocrinology ; 107(3): 257-266, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30025403

RESUMO

Pancreatic neuroendocrine neoplasias (pNEN) are the most common cause of death in adult patients with multiple endocrine neoplasia type 1 (MEN1). So far, only few chemopreventive strategies (e.g., with somatostatin analogues) have been evaluated for MEN1 associated pNENs. In this experimental study on 75 Men1(+/T) knockout mice, the effect of aspirin (n = 25) and an inhibitor of angiotensin-I converting enzyme (enalapril, n = 25) compared to controls (n = 25) were evaluated as single chemopreventive strategies for pNENs after 6, 9, 12, 15, and 18 months. After each study period, mice were sacrificed and the resected pancreata were evaluated by histopathological analysis, immunostaining, and real-time PCR. PNEN size and number was measured. Aspirin and enalapril lead to a pNEN size reduction of 80% (167,518 vs. 838,876 µm2, p < 0.001) and 79% (174,758 vs. 838,876 µm2, p < 0.001) compared to controls. Furthermore, aspirin and enalapril treatment resulted in a significant reduction of the number of pNENs by 33%, (p = 0.04) and 41% (p = 0.002) respectively. The apoptosis marker caspase 3 revealed a higher positive expression in pNEN of treated Men1(+/T) mice. Immunostaining of VEGF in pNEN detected a downregulation of its expression in treated Men1(+/T) mice compared to the control group. REL A transcript was significantly downregulated in 18-months treated enalapril Men1(+/T) mice, but not in aspirin-treated Men1(+/T) mice. There was no significant difference in the Ki-67 index. Using a transgenic mouse model that imitates human MEN1, this study provides first evidence that aspirin and enalapril are effective chemopreventive agents that aid in the progression of pNENs.


Assuntos
Aspirina/uso terapêutico , Quimioprevenção/métodos , Enalapril/uso terapêutico , Neoplasia Endócrina Múltipla Tipo 1/patologia , Tumores Neuroendócrinos/prevenção & controle , Neoplasias Pancreáticas/prevenção & controle , Proteínas Proto-Oncogênicas/genética , Animais , Camundongos , Camundongos Knockout , Neoplasia Endócrina Múltipla Tipo 1/genética , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-30519369

RESUMO

BACKGROUND: Pancreatic cancer screening is recommended to individuals at risk (IAR) of familial pancreatic cancer (FPC) families, but little is known about the acceptance of such screening programs. Thus, the acceptance and psychological aspects of a controlled FPC screening program was evaluated. METHODS: IAR of FPC families underwent comprehensive counseling by a geneticist and pancreatologist prior to the proposed screening. Participating IAR, IAR who discontinued screening and IAR who never participated in the screening program were invited to complete questionnaires to assess the motivation for participating in surveillance, cancer worries, structural distress and experiences with participation. Questionnaires were completed anonymously to receive most accurate answers. RESULTS: Of 286 IAR to whom pancreatic ductal adenocarcinoma (PDAC) screening was recommended, 139 (48.6%) IAR regularly participated (group 1), 49 (17.1%) IAR (group 2) discontinued screening after median 1 (1-10) screening visits and 98 (34.2%) IAR (group 3) never underwent screening. The overall response rate of questionnaires was 67% (189/286) with rates of 100% (139 of 139 IAR), 49% (29 of 49 IAR) and 23.4% (23 of 98 IAR) for groups 1, 2 and 3, respectively. At least 93% of IAR felt adequately informed about the screening program after initial counseling. However, only 38.8% received knowledge of or the recommendation for PDAC screening by physicians. The reported cancer-related distress and the fear of investigations were highest in group 1, but acceptably low in all three groups. The main reasons to discontinue or not to participate in screening were the time efforts and travel costs (groups 2 and 3 48,7%). CONCLUSION: Less than 50% of IAR regularly participate in a proposed PDAC screening program, although the associated psychological burden is quite low. Physicians should be educated about high risk PDAC groups and screening recommendations. Time and travel efforts must be reduced to encourage more IAR to participate in a recommended screening.

12.
World J Surg ; 41(6): 1521-1527, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28138732

RESUMO

BACKGROUND: Routine screening is recommended for patients with multiple endocrine neoplasia type 1 (MEN1) to enable early detection and treatment of associated neuroendocrine neoplasms (NEN). Gallium68-DOTATOC-Positron emission tomography combined with computed tomography (Ga-68-DOTATOC-PET-CT) is a very sensitive and specific imaging technique for the detection of sporadic neuroendocrine tumors. The present study evaluated the value of Ga-68-DOTATOC-PET-CT in routine screening of patients with MEN1. METHODS: Between January 2014 and March 2016, all MEN1 patients underwent Ga-68-DOTATOC-PET-CT in addition to conventional imaging (computed tomography of the thorax, magnetic resonance imaging of the abdomen and pituitary, endoscopic ultrasonography). The diagnostic yield of conventional imaging and Ga-68-DOTATOC-PET-CT was prospectively documented and compared, and treatment changes caused by the addition of Ga-68-DOTATOC-PET-CT were recorded. RESULTS: Conventional imaging detected 145 NENs, mainly pancreaticoduodenal NENs (n = 117, 81%), in 31 of 33 MEN1 patients. Ga-68-DOTATOC-PET-CT detected 55 NENs in 23 of the 33 patients (p = 0.0001). Ninety (62%) NENs detected by conventional imaging were missed by DOTATOC-PET-CT. The majority of missed lesions were pNEN (n = 68; 74%). The sensitivity of Ga-68-DOTATOC-PET-CT for NENs <5, 5-9, 10-19 and ≥20 mm was 0, 29, 81 and 100%, respectively. However, Ga-68-DOTATOC-PET-CT detected more liver and lymph node metastases in patients with known metastatic disease, which did not lead to a change of patients' management. In one patient (3%), Ga-68-DOTATOC-PET-CT was the only imaging modality that detected a small intestine NEN and led to potentially curative surgery. CONCLUSION: Ga-68-DOTATOC-PET-CT cannot be recommended for routine screening of MEN1 patients. It might provide important additional information in patients with suspected or known metastatic disease.


Assuntos
Neoplasia Endócrina Múltipla Tipo 1/diagnóstico por imagem , Octreotida/análogos & derivados , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
World J Surg ; 41(8): 2026-2032, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28321559

RESUMO

BACKGROUND: Recent clinical practice guidelines recommend that routine screening of MEN1 mutation carriers should start at the age of 5 years. The occurrence of clinically relevant MEN1 organ manifestations in children (≤18 years) was evaluated. METHODS: Two prospective collected databases of MEN1 patients (n = 166) who underwent annual screening were retrospectively analyzed for organ manifestations in MEN1 patients ≤18 years. The follow-up was based on the most recent screening examination until December 2015. RESULTS: Twenty [11 females, 9 males, (12%)] of 166 MEN1 patients were diagnosed with at least one organ manifestation at age ≤18 years. The most frequent manifestation was mild asymptomatic pHPT (n = 9, 45%, age range 8-18 years). Eight (40%) young patients had pNENs (three non-functioning pNENs, five insulinomas, age range 9-18 years). All five insulinomas were diagnosed based on hypoglycemic symptoms. The other organ manifestations were asymptomatic pituitary adenomas in six patients (30%, age range 15-18 years) and a bronchial carcinoid in one 15-year-old patient. Only six (30%) patients ≤18 years had clinically relevant organ manifestations. CONCLUSION: Symptomatic or severe manifestations in MEN1 patients rarely occur below the age of 16 years. With regard to psychological burden and cost-effectiveness, routine screening of asymptomatic MEN1 patients should be postponed at least until the age of 16 years.


Assuntos
Neoplasia Endócrina Múltipla Tipo 1/diagnóstico , Adolescente , Criança , Feminino , Humanos , Insulinoma/etiologia , Masculino , Neoplasia Endócrina Múltipla Tipo 1/complicações , Neoplasias Pancreáticas/etiologia , Neoplasias Hipofisárias/etiologia , Estudos Prospectivos , Estudos Retrospectivos
14.
Neuroendocrinology ; 103(3-4): 240-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26113081

RESUMO

OBJECTIVE: The prevalence and clinical behavior of bronchopulmonary neuroendocrine tumors (bNET) associated with multiple endocrine neoplasia type 1 (MEN1) are not well defined. This study aimed to determine the prevalence, potential precursor lesions and prognosis of bNET in patients with MEN1. METHODS: A database of 75 prospectively collected MEN1 cases was retrospectively analyzed for bNET. Patient characteristics, imaging and treatment were evaluated. Resection specimens of operated patients were reassessed by two specialized pathologists. Available CT scans of the whole cohort were reviewed to determine the prevalence of bronchopulmonary nodules. RESULTS: Five of the 75 MEN1 patients (6.6%; 2 male, 3 female) developed histologically confirmed bNET after a median follow-up of 134 months. The median age at diagnosis of bNET was 47 years (range 31-67), and all patients were asymptomatic. Four patients underwent anatomic lung resections with lymphadenectomy; the remaining patient with multiple lesions had only a wedge resection of the largest bNET. Tumor sizes ranged from 7 to 32 mm in diameter, and all bNET were well differentiated. Two patients had lymph node metastases. Two of 4 reevaluated resection specimens revealed multifocal bNET, and 3 specimens showed tumorlets (up to 3) associated with multifocal areas of a neuroendocrine cell hyperplasia within the subsegmental bronchi. One bNET-related death (1.3%) occurred during long-term follow-up. Review of the available CT scans of the patients without proven bNET revealed small bronchopulmonary lesions (≥3 mm) in 16 of 53 cases (30.2%). CONCLUSIONS: bNET in MEN1 might be more common than previously recognized. Their natural course seems to be rather benign. Multifocal tumorlets and multifocal neuroendocrine cell hyperplasia might represent their precursor lesions.


Assuntos
Neoplasias Brônquicas/complicações , Neoplasias Brônquicas/epidemiologia , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/epidemiologia , Neoplasia Endócrina Múltipla Tipo 1/epidemiologia , Adulto , Idoso , Neoplasias Brônquicas/diagnóstico por imagem , Neoplasias Brônquicas/patologia , Estudos de Coortes , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/diagnóstico por imagem , Neoplasia Endócrina Múltipla Tipo 1/patologia , Neoplasia Endócrina Múltipla Tipo 1/cirurgia , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/cirurgia , Tomografia Computadorizada de Emissão
15.
J Cell Mol Med ; 19(5): 948-59, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25754106

RESUMO

Hypersecretion is the major symptom of functional neuroendocrine tumours. The mechanisms that contribute to this excessive secretion of hormones are still elusive. A key event in secretion is the exit of secretory products from the Golgi apparatus. ADP-ribosylation factor (Arf) GTPases are known to control vesicle budding and trafficking, and have a leading function in the regulation of formation of secretory granula at the Golgi. Here, we show that Arf1 is the predominant Arf protein family member expressed in the neuroendocrine pancreatic tumour cell lines BON and QGP-1. In BON cells Arf1 colocalizes with Golgi markers as well as chromogranin A, and shows significant basal activity. The inhibition of Arf1 activity or expression significantly impaired secretion of chromogranin A. Furthermore, we show that the insulin-like growth factor 1 (IGF-1), a major regulator of growth and secretion in BON cells, induces Arf1 activity. We found that activation of Arf1 upon IGF-1 receptor stimulation is mediated by MEK/ERK signalling pathway in BON and QGP-1 cells. Moreover, the activity of Arf1 in BON cells is mediated by autocrinely secreted IGF-1, and concomitantly, autocrine IGF1 secretion is maintained by Arf1 activity. In summary, our data indicate an important regulatory role for Arf1 at the Golgi in hypersecretion in neuroendocrine cancer cells.


Assuntos
Fator 1 de Ribosilação do ADP/metabolismo , Cromogranina A/metabolismo , Complexo de Golgi/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Fator 1 de Ribosilação do ADP/genética , Autoantígenos/metabolismo , Western Blotting , Tumor Carcinoide/genética , Tumor Carcinoide/metabolismo , Tumor Carcinoide/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexo de Golgi/ultraestrutura , Proteínas da Matriz do Complexo de Golgi , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Ligação Proteica , Interferência de RNA , Receptor IGF Tipo 1/metabolismo
16.
Mol Carcinog ; 54(8): 585-97, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24375802

RESUMO

Deacetylase inhibitors (DACi) are a new class of drugs with a broad spectrum of mechanisms that favor their application in cancer therapy. Currently, the exact mechanisms and cellular effects of DACi have not been fully elucidated. In addition to their effects on histone acetylation, DACi can interfere with gene expression via miRNA pathways. Treatment with panobinostat (LBH589), a novel potent DACi, led to the highly aberrant modulation of several miRNAs in hepatocellular carcinoma (HCC) cell lines as shown by miRNA array analysis. Among them, hsa-miR-19a, hsa-miR-19b1 and the corresponding precursors were down-regulated by panobinostat in TP53(-/-) Hep3B and TP53(+/+) HepG2 cell lines; hsa-miR30a-5p mature form only was suppressed in both HCC cell lines, as confirmed by further RT-qPCR analysis. In HCC cell lines, panobinostat caused the upregulation of the predicted miRNA targets APAF1 and Beclin1 protein levels. Transfection with oligonucleotides mimicking these miRNAs led to an increase in the viability rate of both cell lines as analyzed by impedance-based real-time cell analysis. In addition, transfecting miRNA mimicking oligonucleotides resulted in the decrease of APAF1, Beclin1 and PAK6 at the protein level, proving the regulating influence of the investigated miRNAs on gene final products. The overexpression of the above mentioned oncomiRs in Hep3B and HepG2 cell lines leads to cell proliferation and downregulation of cell death associated proteins. In our model, panobinostat exerts its anti-cancer effect by suppressing these miRNAs and restoring the expression of their corresponding tumor suppressor targets.


Assuntos
Carcinoma Hepatocelular/genética , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Indóis/farmacologia , Neoplasias Hepáticas/genética , MicroRNAs/genética , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Fator Apoptótico 1 Ativador de Proteases/genética , Fator Apoptótico 1 Ativador de Proteases/metabolismo , Proteína Beclina-1 , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Panobinostat , Quinases Ativadas por p21/genética , Quinases Ativadas por p21/metabolismo
17.
Food Nutr Bull ; 35(3 Suppl): S108-16, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25902580

RESUMO

BACKGROUND: The Health in Action Program was established in Brazil in 2010 to address the critical issues of health and nutrition among vulnerable children in the northeast and southeast regions of the country. By offering school-based nutrition education and increased access to nutritious foods from school gardens, the program has benefited more than 200,000 children aged 6 through 14 years in 430 schools and an additional 670,000 family and community members. The program is now expanding to reach an additional 260,000 students in 570 schools. OBJECTIVE: The purpose of this study was to perform a Program Impact Pathways (PIP) analysis to identify Critical Quality Control Points (CCPs) and a suite of impact indicators in order to better understand and illustrate the impact of the program. METHODS: The analyses of the PIP and the suite of impact indicators were conducted in collaboration with INMED Brasil's program management and evaluation team and the international evaluation team of INMED Partnerships for Children. INMED presented the results at a seven-country Healthy Lifestyles Program Evaluation Workshop held in Granada, Spain, 13-14 September 2013, hosted by the Mondelez International Foundation, where it received feedback from evaluation experts. RESULTS: The PIP analysis enabled INMED to clarify the goals of the program, understand the ways in which program activities lead to stated goals, identify CCPs to monitor, and select achievable impact indicators, including changes in diet, physical activity, and knowledge, attitudes, and behaviors, as well as body mass index. CONCLUSIONS: While the program had previously demonstrated benefits through internal impact evaluation, the PIP Healthy Lifestyles Program Evaluation Workshop led to the identification of potential improvements in program processes and activities, as well as corresponding evaluation methodologies.


Assuntos
Educação em Saúde , Promoção da Saúde , Avaliação de Programas e Projetos de Saúde , Serviços de Saúde Escolar , Adolescente , Índice de Massa Corporal , Brasil , Criança , Ciências da Nutrição Infantil/educação , Culinária/métodos , Dieta , Comportamento Alimentar , Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/métodos , Humanos , Estilo de Vida , Ciências da Nutrição/educação , Valor Nutritivo , Plantas Comestíveis/crescimento & desenvolvimento , Espanha , Estudantes , Verduras/crescimento & desenvolvimento
18.
J Neuroendocrinol ; 36(2): e13364, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38246597

RESUMO

Neuroendocrine tumors of the small intestine (SI-NETs) often develop lymph node metastasis (LNM)-induced mesenteric fibrosis (MF). MF can cause intestinal obstruction as well as ischemia and render surgical resection technically challenging. The underlying pathomechanisms of MF are still not well understood. We examined mesenteric LNM and the surrounding stroma compartment from 24 SI-NET patients, including 11 with in situ presentation of strong MF (MF+) and 13 without MF (MF-). Differential gene expression was assessed with the HTG EdgeSeq Oncology Biomarker Panel comparing MF+ with MF- within LNM and paired stromal samples, respectively. Most interesting differentially expressed genes were validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in combination with validation of associated protein levels utilizing immunohistochemistry (IHC) staining of MF+ and MF- formalin-fixed, paraffin-embedded (FFPE) patient samples. Overall, 14 genes measured with a 2549-gene expression panel were differentially expressed in MF+ patients compared to MF-. Of those, nine were differentially expressed genes in LNM and five genes in the stromal tissue (>2-fold change, p < .05). The top hits included increased COMP and COL11A1 expression in the stroma of MF+ patients compared to MF-, as well as decreased HMGA2, COL6A6, and SLC22A3 expression in LNM of MF+ patients compared to LNM of MF- patients. RT-qPCR confirmed high levels of COMP and COL11A1 in stroma samples of MF+ compared to MF- patients. IHC staining confirmed the enrichment of α-smooth muscle actin-positive fibrosis in MF+ compared to MF- patients with corresponding increase of COMP-expressing stromal cells in MF+. Since COMP is associated with the known driver for fibrosis development transforming growth factor beta and with a cancer-associated fibroblasts enriched environment, it seems to be a promising new target for MF research.


Assuntos
Neoplasias Intestinais , Tumores Neuroendócrinos , Humanos , Actinas , Tumores Neuroendócrinos/patologia , Neoplasias Intestinais/patologia , Fibrose , Metástase Linfática/patologia , Células Estromais/patologia , Músculo Liso/patologia
19.
PLoS One ; 18(1): e0280399, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36701413

RESUMO

BACKGROUND: The low five-year survival rate of pancreatic ductal adenocarcinoma (PDAC) and the low diagnostic rate of early-stage PDAC via imaging highlight the need to discover novel biomarkers and improve the current screening procedures for early diagnosis. Familial pancreatic cancer (FPC) describes the cases of PDAC that are present in two or more individuals within a circle of first-degree relatives. Using innovative high-throughput proteomics, we were able to quantify the protein profiles of individuals at risk from FPC families in different potential pre-cancer stages. However, the high-dimensional proteomics data structure challenges the use of traditional statistical analysis tools. Hence, we applied advanced statistical learning methods to enhance the analysis and improve the results' interpretability. METHODS: We applied model-based gradient boosting and adaptive lasso to deal with the small, unbalanced study design via simultaneous variable selection and model fitting. In addition, we used stability selection to identify a stable subset of selected biomarkers and, as a result, obtain even more interpretable results. In each step, we compared the performance of the different analytical pipelines and validated our approaches via simulation scenarios. RESULTS: In the simulation study, model-based gradient boosting showed a more accurate prediction performance in the small, unbalanced, and high-dimensional datasets than adaptive lasso and could identify more relevant variables. Furthermore, using model-based gradient boosting, we discovered a subset of promising serum biomarkers that may potentially improve the current screening procedure of FPC. CONCLUSION: Advanced statistical learning methods helped us overcome the shortcomings of an unbalanced study design in a valuable clinical dataset. The discovered serum biomarkers provide us with a clear direction for further investigations and more precise clinical hypotheses regarding the development of FPC and optimal strategies for its early detection.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Proteômica , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/patologia , Biomarcadores , Biomarcadores Tumorais/genética , Neoplasias Pancreáticas
20.
Fam Cancer ; 22(3): 323-330, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36717525

RESUMO

Familial pancreatic cancer (FPC) is a rare hereditary tumor entity with broad phenotypic heterogeneity, including colorectal carcinoma (CRC) in some families. The underlying factors for this co-occurrence are still not well evaluated. FPC families in the National Case Collection of Familial Pancreatic Cancer with an additional occurrence of CRC were analyzed regarding the phenotype, genotype and recommendation for a clinical screening program. The total cohort of 272 FPC families included 30 (11%) families with at least one CRC case. The proportion of affected family members with PDAC was 16.1% (73/451) compared to 9.3% of family members with CRC (42/451, p < 0.01). Females were affected with PDAC in 49% (36/73) and CRC in 38% (16/42). The median age of PDAC was 63 compared to 66 years in CRC, whereas 8 (26.6%) of families had an early onset of PDAC and 2 (6.7%) of CRC. Seventeen families had 2 or more affected generations with PDAC and 6 families with CRC. Eleven (9.6%) of affected patients had both PDAC and CRC. Potentially causative germline mutations (2 ATM, 1 CDKN2a, 1 MLH1, 1 PALB2) were detected in 5 of 18 (27.7%) analyzed cases. These findings provide a step forward to include the phenotypic and genotypic characteristics of FPC-CRC families for the genetic counseling and management of these families. Nevertheless, results need to be verified in a larger patient cohort beforehand.


Assuntos
Predisposição Genética para Doença , Neoplasias Pancreáticas , Feminino , Humanos , Neoplasias Pancreáticas/diagnóstico , Mutação em Linhagem Germinativa , Genótipo
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