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1.
PLoS One ; 15(2): e0228894, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32078667

RESUMO

Lymphangioleiomyomatosis (LAM) is a devastating lung disease caused by inactivating gene mutations in either TSC1 or TSC2 that result in hyperactivation of the mechanistic target of rapamycin complex 1 (mTORC1). As LAM occurs predominantly in women during their reproductive age and is exacerbated by pregnancy, the female hormonal environment, and in particular estrogen, is implicated in LAM pathogenesis and progression. However, detailed underlying molecular mechanisms are not well understood. In this study, utilizing human pulmonary LAM specimens and cell culture models of TSC2-deficient LAM patient-derived and rat uterine leiomyoma-derived cells, we tested the hypothesis that estrogen promotes the growth of mTORC1-hyperactive cells through pyruvate kinase M2 (PKM2). Estrogen increased the phosphorylation of PKM2 at Ser37 and induced the nuclear translocation of phospho-PKM2. The estrogen receptor antagonist Faslodex reversed these effects. Restoration of TSC2 inhibited the phosphorylation of PKM2 in an mTORC1 inhibitor-insensitive manner. Finally, accumulation of phosphorylated PKM2 was evident in pulmonary nodule from LAM patients. Together, our data suggest that female predominance of LAM might be at least in part attributed to estrogen stimulation of PKM2-mediated cellular metabolic alterations. Targeting metabolic regulators of PKM2 might have therapeutic benefits for women with LAM and other female-specific neoplasms.


Assuntos
Estrogênios/metabolismo , Piruvato Quinase/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/genética , Animais , Linhagem Celular Tumoral , Estrogênios/fisiologia , Feminino , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Linfangioleiomiomatose/genética , Linfangioleiomiomatose/fisiopatologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Fosforilação , Piruvato Quinase/fisiologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 1 do Complexo Esclerose Tuberosa/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Proteínas Supressoras de Tumor/genética
2.
PLoS One ; 15(1): e0228204, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978189

RESUMO

OBJECTIVE: To clarify the complex mechanism underlying epileptogeneis, a novel animal model was generated. METHODS: In our previous research, we have generated a melanocyte-lineage mTOR hyperactivation mouse model (Mitf-M-Cre Tsc2 KO mice; cKO mice) to investigate mTOR pathway in melanogenesis regulation, markedly reduced skin pigmentation was observed. Very unexpectedly, spontaneous recurrent epilepsy was also developed in this mouse model. RESULTS: Compared with control littermates, no change was found in either brain size or brain mass in cKO mice. Hematoxylin staining revealed no obvious aberrant histologic features in the whole brains of cKO mice. Histoimmunofluorescence staining and electron microscopy examination revealed markedly increased mTOR signaling and hyperproliferation of mitochondria in cKO mice, especially in the hippocampus. Furthermore, rapamycin treatment reversed these abnormalities. CONCLUSIONS: This study suggests that our melanocyte-lineage mTOR hyperactivation mouse is a novel animal model of epilepsy, which may promote the progress of both epilepsy and neurophysiology research.


Assuntos
Epilepsia/patologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Encéfalo/patologia , Encéfalo/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Eletroencefalografia , Epilepsia/tratamento farmacológico , Epilepsia/metabolismo , Hipocampo/citologia , Hipocampo/metabolismo , Hipocampo/patologia , Melanócitos/citologia , Melanócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR/antagonistas & inibidores , Proteína 2 do Complexo Esclerose Tuberosa/deficiência , Proteína 2 do Complexo Esclerose Tuberosa/genética
3.
Cancer Sci ; 111(3): 840-848, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31925975

RESUMO

Ionizing radiation can damage DNA and, therefore, is a risk factor for cancer. Eker rats, which carry a heterozygous germline mutation in the tumor-suppressor gene tuberous sclerosis complex 2 (Tsc2), are susceptible to radiation-induced renal carcinogenesis. However, the molecular mechanisms involved in Tsc2 inactivation are unclear. We subjected Fischer 344 × Eker (Long Evans Tsc2+/- ) F1 hybrid rats to gamma-irradiation (2 Gy) at gestational day 19 (GD19) or postnatal day 5 (PND5) and investigated the patterns of genomic alterations in the Tsc2 allele of renal tumors that developed at 1 year after irradiation (N = 24 tumors for GD19, N = 10 for PND5), in comparison with spontaneously developed tumors (N = 8 tumors). Gamma-irradiation significantly increased the multiplicity of renal tumors. The frequency of LOH at the chromosome 10q12 region, including the Tsc2 locus, was 38%, 29% and 60% in renal carcinomas developed from the nonirradiated, GD19 and PND5 groups, respectively. Array comparative genomic hybridization analysis revealed that the LOH patterns on chromosome 10 in renal carcinomas were classified into chromosomal missegregation, mitotic recombination and chromosomal deletion types. LOH of the interstitial chromosomal deletion type was observed only in radiation-associated carcinomas. Sequence analysis for the wild-type Tsc2 allele in the LOH-negative carcinomas identified deletions (nonirradiated: 26%; GD19: 21%) and base-substitution mutations (GD19: 4%). Reduced expression of Tsc2 was also observed in the majority of the LOH-negative carcinomas. Our results suggest that interstitial chromosomal deletion is a characteristic mutagenic event caused by ionizing radiation, and it may contribute to the assessment of radiation-induced cancer risk.


Assuntos
Neoplasias Renais/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Esclerose Tuberosa/genética , Alelos , Animais , Deleção Cromossômica , Cromossomos Humanos Par 10/genética , Hibridização Genômica Comparativa/métodos , Raios gama/efeitos adversos , Heterozigoto , Humanos , Masculino , Mutação/genética , Ratos , Ratos Endogâmicos F344 , Ratos Long-Evans , Risco , Proteínas Supressoras de Tumor/genética
4.
Int J Cancer ; 146(5): 1435-1444, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31335987

RESUMO

The mammalian target of rapamycin (mTOR) pathway inhibitors are key drugs for the treatment of many tumor types, however, there are no predictive biomarkers in clinical use. Here, we performed a molecular and immunohistochemical characterization of key mTOR pathway components in a series of 105 renal cell carcinoma patients treated with rapalogs, aimed at identifying markers of treatment response. Mutational analysis in MTOR, TSC1 and TSC2 was performed through targeted next-generation sequencing (NGS), and immunohistochemistry (IHC) was performed for PTEN, pAKT, pS6K1, pS6 and p21. Among patients with NGS data, 11 of 87 (13%) had mTOR pathway mutations (8 in MTOR, 1 in TSC1 and 2 in TSC2). When comparing the molecular data to the response of the patients, we found that partial response was more frequent in cases with mTOR pathway mutations than in those without mutations (odds ratio [OR] = 0.08, 95% confidence interval [CI] = 0.008-0.79, p = 0.030 univariate; p = 0.038 multivariable). Regarding IHC, negative PTEN staining was detected in 58% of the tumors, and it was more frequent in rapalog responder patients (OR = 0.24, 95% CI = 0.065-0.86, p = 0.029 univariate; p = 0.029 multivariable). Mutations and PTEN IHC were not mutually exclusive events and its combination improved response prediction (OR = 0.16, 95% CI = 0.04-0.62, p = 0.008 univariate; p = 0.013 multivariable). The staining of other proteins did not show and association with response and no association with PFS was observed in unselected patients. In conclusion, our findings suggest that mTOR pathway mutations, negative PTEN IHC and their combination are potential markers of rapalog response.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Renais/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/mortalidade , Análise Mutacional de DNA , Everolimo/farmacologia , Everolimo/uso terapêutico , Feminino , Seguimentos , Humanos , Rim/patologia , Neoplasias Renais/genética , Neoplasias Renais/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , PTEN Fosfo-Hidrolase/metabolismo , Prognóstico , Intervalo Livre de Progressão , Estudos Prospectivos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sirolimo/análogos & derivados , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética
5.
Biol Res ; 52(1): 58, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783925

RESUMO

BACKGROUND: Our previous study showed that knockdown of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) attenuated myocardial apoptosis in mouse acute myocardial infarction (AMI). This study aims to explore whether MALAT1 enhanced cardiomyocyte apoptosis via autophagy regulation and the underlying mechanisms of MALAT1 regulating autophagy. METHODS: Cardiomyocytes were isolated from neonatal mice and then stimulated with hypoxia/reoxygenation (H/R) injury to mimic AMI. The autophagy level was assessed using GFP-LC3 immunofluorescence and western blot analysis of autophagy-related proteins. RNA pull-down and RNA immunoprecipitation (RIP) was performed to analyze the binding of MALAT1 and EZH2. Chromatin immunoprecipitation (ChIP) assay was performed to analyze the binding of TSC2 promoter and EZH2. The cell apoptosis was evaluated using TUNEL staining and western blot analysis of apoptosis-related proteins. RESULTS: H/R injury increased MALAT1 expression in cardiomyocytes. Furthermore, MALAT1 overexpression inhibited, whereas MALAT1 knockdown enhanced the autophagy of cardiomyocytes. Moreover, MALAT1 overexpression recruited EZH2 to TSC2 promoter regions to elevate H3K27me3 and epigenetically inhibited TSC2 transcription. Importantly, TSC2 overexpression suppressed mTOR signaling and then activated the autophagy. Further results showed that MALAT1 inhibited proliferation and enhanced apoptosis of cardiomyocytes through inhibiting TSC2 and autophagy. CONCLUSION: These findings demonstrate that the increased MALAT1 expression induced by H/R injury enhances cardiomyocyte apoptosis through autophagy inhibition by regulating TSC2-mTOR signaling.


Assuntos
Apoptose/fisiologia , Autofagia/fisiologia , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/genética , Serina-Treonina Quinases TOR/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Animais , Apoptose/genética , Autofagia/genética , Western Blotting , Imunoprecipitação da Cromatina , Imunofluorescência , Camundongos , RNA Longo não Codificante/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo
6.
PLoS One ; 14(12): e0226400, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31856217

RESUMO

The aim of our study was to elucidate the landscapes of genetic alterations of TSC1 and TSC2 as well as other possible non-TSC1/2 in Lymphangioleiomyomatosis (LAM) patients. Sixty-one Chinese LAM patients' clinical information was collected. Tumor biopsies and matched leukocytes from these patients were retrospectively analyzed by next generation sequencing (NGS), chromosomal microarray analysis (CMA), and multiplex ligation-dependent probe amplification (MLPA). Eighty-six TSC1/2 variants were identified in 46 of the 61 LAM patients (75.4%) in which TSC2 and TSC1 variants were 88.37% and 11.63% respectively. The 86 variants are composed of (i) 52 single nucleotide variants (SNVs) (including 30 novel variants), (ii) 23 indels (including 21deletions, and 2 insertions), (iii) a germline duplication of exon 31-42 of TSC2, (iv) a 2.68 Mb somatic duplication containing TSC2, and (v) 9 regions with copy-neutral loss of heterogeneity (CN-LOHs) present only in the LAM patients with single TSC1/2 mutations. Sixty-one non-TSC1/2 variants in 31 genes were identified in 37 LAM patients. Combined applications of different techniques are necessary to achieve maximal detection rate of TSC1/2 variants in LAM patients. Thirty novel TSC1/2 variants expands the spectrum of TSC1/2 in LAM patients. Identification of 61 non-TSC1/2 variants suggests that alternative genes might have contributed to the initiation and progression of LAM.


Assuntos
Linfangioleiomiomatose/genética , Mutação , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Adulto , China , Variações do Número de Cópias de DNA , Feminino , Humanos , Linfangioleiomiomatose/diagnóstico por imagem , Linfangioleiomiomatose/patologia , Polimorfismo de Nucleotídeo Único
7.
BMC Med Genet ; 20(1): 164, 2019 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655562

RESUMO

BACKGROUND: Mutations in TSC1 or TSC2 gene cause tuberous sclerosis complex (TSC), an autosomal dominant disorder characterized by the formation of non-malignant hamartomas in multiple vital organs. TSC1 and TSC2 gene products form TSC heterodimer that senses specific cell growth conditions to control mTORC1 signalling. METHODS: In the present study 98 TSC patients were tested for variants in TSC1 and TSC2 genes and 14 novel missense variations were identified. The pathogenecity of these novel variations was determined by applying different bioinformatics tools involving computer aided protein modeling. RESULTS: Protein modelling could be done only for ten variants which were within the functional part of the protein. Homology modeling is the most reliable method for structure prediction of a protein. Since no sequence homology structure was available for the tuberin protein, three dimensional structure was modeled by a combination of homology modeling and the predictive fold recognition and threading method using Phyre2 threading server. The best template structures for model building of the TSC1 interacting domain, tuberin domain and GAP domain are the crystal structures of clathrin adaptor core protein, Rap1GAP catalytic domain and Ser/Thr kinase Tor protein respectively. CONCLUSIONS: In this study, an attempt has been made to assess the impact of each novel missense variant based on their TSC1-TSC2 hydrophobic interactions and its effect on protein function.


Assuntos
Mutação de Sentido Incorreto , Proteína 2 do Complexo Esclerose Tuberosa/genética , Esclerose Tuberosa/genética , Adolescente , Criança , Pré-Escolar , Simulação por Computador , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lactente , Recém-Nascido , Esclerose Tuberosa/patologia , Proteína 1 do Complexo Esclerose Tuberosa/genética
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(10): 1019-1021, 2019 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-31598950

RESUMO

OBJECTIVE: To identify pathogenic mutation of TSC1 and TSC2 genes in a patient with long-time misdiagnosis of epilepsy. METHODS: Peripheral blood samples and clinical data of the patient and her 2 parents were collected. Potential mutation of TSC1 and TSC2 genes were detected by direct sequencing. RESULTS: The patient had frequent episodes of epilepsy in addition with Shagreen patches for 10 years. A frame-shifting mutation c.2509_2512delAACA was detected in exon 20 of the TSC1 gene. This same mutation was not found in her unaffected parents. CONCLUSION: The recurrent frame-shifting mutation c.2509_2512delAACA (p.Asn837ValfsX11) of the TSC1 gene probably underlies the disease in this patient.


Assuntos
Epilepsia/diagnóstico , Epilepsia/genética , Esclerose Tuberosa/diagnóstico , Esclerose Tuberosa/genética , Erros de Diagnóstico , Feminino , Mutação da Fase de Leitura , Humanos , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética
9.
Ren Fail ; 41(1): 842-849, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31488014

RESUMO

Purpose: Autosomal dominant polycystic kidney disease (ADPKD) is characterized by progressive development of kidney cysts and enlargement and dysfunction of the kidneys. The Consortium of Radiologic Imaging Studies of the Polycystic Kidney Disease (CRISP) cohort revealed that 89.1% had either a PKD1 or PKD2 mutation. Of the CRISP patients with a genetic cause detected, mutations in PKD1 accounted for 85%, while mutations in the PKD2 accounted for the remaining 15%. Here, we report exome sequencing of 16 Saudi patients diagnosed with ADPKD and 16 ethnically matched controls. Methods: Exome sequencing was performed using combinatorial probe-anchor synthesis and improved DNA Nanoballs technology on BGISEQ-500 sequencers (BGI, China) using the BGI Exome V4 (59 Mb) Kit. Identified variants were validated with Sanger sequencing. Results: With the exception of GC-rich exon 1, we obtained excellent coverage of PKD1 (mean read depth = 88) including both duplicated and non-duplicated regions. Of nine patients with typical ADPKD presentations (bilateral symmetrical kidney involvement, positive family history, concordant imaging, and kidney function), four had protein truncating PKD1 mutations, one had a PKD1 missense mutation, and one had a PKD2 mutation. These variants have not been previously observed in the Saudi population. In seven clinically diagnosed ADPKD cases but with atypical features, no PKD1 or PKD2 mutations were identified, but rare predicted pathogenic heterozygous variants were found in cystogenic candidate genes including PKHD1, PKD1L3, EGF, CFTR, and TSC2. Conclusions: Mutations in PKD1 and PKD2 are the most common cause of ADPKD in Saudi patients with typical ADPKD. Abbreviations: ADPKD: Autosomal dominant polycystic kidney disease; CFTR: Cystic fibrosis transmembrane conductance regulator; EGF: Epidermal growth factor; MCIC: Mayo Clinic Imaging Classification; PKD: Polycystic kidney disease; TSC2: Tuberous sclerosis complex 2.


Assuntos
Rim Policístico Autossômico Dominante/genética , Adulto , Idoso , Árabes/genética , Canais de Cálcio/genética , Estudos de Casos e Controles , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Análise Mutacional de DNA , Fator de Crescimento Epidérmico/genética , Éxons/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Rim Policístico Autossômico Dominante/diagnóstico por imagem , Receptores de Superfície Celular/genética , Arábia Saudita , Canais de Cátion TRPP/genética , Tomografia Computadorizada por Raios X , Proteína 2 do Complexo Esclerose Tuberosa/genética , Sequenciamento Completo do Exoma
10.
Indian J Cancer ; 56(3): 274-275, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31389395

RESUMO

We report a case of a 67-year-old man with pazopanib-resistant metastatic renal cell carcinoma (mRCC) who showed an exceptional response to everolimus. Furthermore, this patient had TSC1 and TSC2 mutations. Only a subset of patients with mRCC respond to mTOR inhibitors and emerging evidences indicate that TSC1 and TSC2 mutations could be markers of response to mTOR inhibition. The current case study supports these accruing evidences.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Renais/secundário , Everolimo/uso terapêutico , Neoplasias Renais/patologia , Mutação , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Idoso , Antineoplásicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Masculino , Prognóstico
11.
Dermatol Clin ; 37(4): 583-606, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31466597

RESUMO

Phakomatoses present with characteristic findings on the skin, central or peripheral nervous system, and tumors. Neurofibromatosis type 1 is the most common syndrome and is characterized by Café-au-lait macules, intertriginous freckling, Lisch nodules, and tumors including neurofibromas, malignant peripheral nerve sheath tumors, and gliomas. Tuberous Sclerosis Complex is characterized by benign hamartomas presenting with hypomelanotic macules, shagreen patches, angiofibromas, confetti lesions and tumors including cortical tubers, subependymal nodules, subependymal giant cell astrocytomas and tumors of the kidney, lung, and heart. Managing these disorders requires disease specific supportive care, tumor monitoring, surveillance for selected cancers, and treatment of comorbid conditions.


Assuntos
Neurofibromatose 1/patologia , Pele/patologia , Esclerose Tuberosa/patologia , Genes da Neurofibromatose 1 , Humanos , Síndromes Neurocutâneas/diagnóstico , Síndromes Neurocutâneas/genética , Síndromes Neurocutâneas/patologia , Síndromes Neurocutâneas/terapia , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/genética , Neurofibromatose 1/terapia , Esclerose Tuberosa/diagnóstico , Esclerose Tuberosa/genética , Esclerose Tuberosa/terapia , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética
12.
Urology ; 133: 96-102, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454656

RESUMO

OBJECTIVE: To elucidate the effect of the biallelic somatic TSC2 mutations, identified in one adolescent patient, in renal cell carcinoma (RCC). METHODS: Mutation analyses, immunohistochemistry and real-time polymerase chain reaction (PCR) were conducted. RESULTS: Two novel somatic mutations of TSC2 in unilateral and solitary RCC samples from a 14-year-old female were identified. The pathological features suggest the tumor as a clear-cell renal cell carcinoma. In addition, immunohistochemistry revealed elevated levels of phosphorylated S6K1. Results from in vitro cellular experiments suggest that the mutant TSC2 proteins were quickly degraded and they failed to repress the phosphorylation of S6K1 and STAT3, which leads to constitutive activation of mTORC1 pathway and ultimately cause the development of RCC. CONCLUSION: Detecting TSC2 mutation in patients with early RCC onset would be beneficial and mTOR inhibitor could be a therapeutic option for TSC2 mutation-induced RCC.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Mutação , Proteína 2 do Complexo Esclerose Tuberosa/genética , Adolescente , Alelos , Feminino , Humanos
13.
Dev Med Child Neurol ; 61(10): 1221-1228, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31313298

RESUMO

AIM: To improve the genetic, clinical, and neuroradiological characterization of cerebellar involvement in tuberous sclerosis complex (TSC) and determine whether cerebellar lesions could be a reliable biomarker of neurological impairment. METHOD: This retrospective cohort study, held at two tertiary paediatric university centres, was conducted on patients with a confirmed diagnosis of TSC who underwent brain magnetic resonance imaging between October 2009 and May 2016. The study population consisted of 112 patients with TSC (median age 10y; range 5mo-38y; 61 females, 51 males). RESULTS: The results from multivariable statistical analysis indicated that cerebellar involvement (34 out of 112 patients, none carrying a TSC1 mutation) was the most powerful predictor of supratentorial cortical tuber load; however, cerebellar involvement was not the best predictor of clinical phenotype when supratentorial tuber load and TSC2 mutations were taken into consideration. The association between cerebellar lesions and a more severe clinical and neuroradiological phenotype was statistically significant and may be due to its strong association with TSC2 mutations and higher cortical tuber load. INTERPRETATION: Cerebellar involvement is not the best predictor of neurobehavioural outcome, including TSC-related autism, after adjusting for TSC2 and the number of cortical tubers. Its role in the TSC clinical phenotype needs to be investigated further. WHAT THIS PAPER ADDS: Cerebellar involvement is a powerful predictor of supratentorial cortical involvement and a potential biomarker of disease severity. Cerebellar lesions significantly correlate with a more severe clinical and neuroradiological phenotype. Cerebellar involvement is not the best predictor of neurobehavioural outcome.


Assuntos
Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Esclerose Tuberosa/diagnóstico , Esclerose Tuberosa/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Mutação , Fenótipo , Estudos Retrospectivos , Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética
14.
BMJ Case Rep ; 12(5)2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31154346

RESUMO

A 14-year-old boy with familial Li-Fraumeni syndrome presented with diplopia. Brain MRI revealed a right temporoparietal rim-enhancing mass. Following surgical resection and diagnosis of a gigantocellular-type glioblastoma multiforme (GBM), his family wished to avoid cytotoxic chemotherapy given the amplified risk of secondary malignancy. As such, we performed whole exome and transcriptome sequencing, which revealed germline TP53 and somatic TSC2 mutations. On completion of adjuvant radiotherapy, he was started on maintenance therapy with everolimus per recommendations from our multi-institutional brain tumour precision medicine tumour board. He has achieved a complete remission with resolution of visual symptoms and remains on everolimus therapy with concurrent electromagnetic field therapy, now 33 months from diagnosis. Our data highlight the benefit of precision medicine in children with GBM and offer insight into a targetable pathway that may be involved in similar cases.


Assuntos
Neoplasias Encefálicas/diagnóstico , Everolimo/uso terapêutico , Glioblastoma/diagnóstico , Imunossupressores/uso terapêutico , Síndrome de Li-Fraumeni , Adolescente , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Terapia Combinada , Diagnóstico Diferencial , Diplopia/etiologia , Glioblastoma/complicações , Glioblastoma/diagnóstico por imagem , Glioblastoma/terapia , Humanos , Masculino , Lobo Parietal , Medicina de Precisão , Lobo Temporal , Proteína 2 do Complexo Esclerose Tuberosa/genética
15.
Biochim Biophys Acta Gene Regul Mech ; 1862(6): 657-669, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31075539

RESUMO

Variation in Disrupted-in-Schizophrenia 1 (DISC1) increases the risk for neurodegenerative diseases, schizophrenia, and other mental disorders. However, the functions of DISC1 associated with the development of these diseases remain unclear. DISC1 has been reported to inhibit Akt/mTORC1 signaling, a major regulator of translation, and recent studies indicate that DISC1 could exert a direct role in translational regulation. Here, we present evidence of a novel role of DISC1 in the maintenance of protein synthesis during oxidative stress. In order to investigate DISC1 function independently of Akt/mTORC1, we used Tsc2-/- cells, where mTORC1 activation is independent of Akt. DISC1 knockdown enhanced inhibition of protein synthesis in cells treated with sodium arsenite (SA), an oxidative agent used for studying stress granules (SGs) dynamics and translational control. N-acetyl-cysteine inhibited the effect of DISC1, suggesting that DISC1 affects translation in response to oxidative stress. DISC1 decreased SGs number in SA-treated cells, but resided outside SGs and maintained protein synthesis independently of a proper SG nucleation. DISC1-dependent stimulation of translation in SA-treated cells was supported by its interaction with eIF3h, a component of the canonical translation initiation machinery. Consistent with a role in the homeostatic maintenance of translation, DISC1 knockdown or overexpression decreased cell viability after SA exposure. Our data suggest that DISC1 is a relevant component of the cellular response to stress, maintaining certain levels of translation and preserving cell integrity. This novel function of DISC1 might be involved in its association with pathologies affecting tissues frequently exposed to oxidative stress.


Assuntos
Arsenitos/farmacologia , Proteínas do Tecido Nervoso/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Compostos de Sódio/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Grânulos Citoplasmáticos/metabolismo , DNA Helicases/metabolismo , Fator de Iniciação 3 em Eucariotos/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Proteínas do Tecido Nervoso/genética , Proteína Oncogênica v-akt , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Transcriptoma , Proteína 2 do Complexo Esclerose Tuberosa/genética
16.
Medicine (Baltimore) ; 98(19): e15545, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31083211

RESUMO

RATIONALE: Tuberous sclerosis complex (TSC) is a relatively rare, autosomal dominant, and progressive neurocutaneous disorder involving multiple organs. Heterozygous mutations in the TSC1 gene located on chromosome 9 (9q34.13) or the TSC2 gene located on chromosome 16 (16p13.3) have been shown to be responsible for this disorder. The most common clinical manifestations are abnormalities of the skin, brain, kidney, heart, and lungs. Although all seizure types have been observed in TSC patients, the present case is the first in the literature to present with convulsive status epilepticus followed by hypoxic cerebropathy. PATIENT CONCERNS: A 33-month-old girl presented with fever and seizure followed by unconsciousness for 6 hours. Physical examination showed 4 hypopigmented macules with diameters exceeding 5 mm. Initial magnetic resonance imaging of the brain revealed diffuse edema in the bilateral cerebral cortex, cortical tubers, and subependymal nodules. Video electroencephalography showed no epileptiform activity, but diffuse slow waves intermixed with small fast waves were seen for all leads. Computed tomography brain scanning revealed bilateral cortex edema and calcified subependymal nodules. DIAGNOSIS: Combined with her clinical presentation, the patient was diagnosed with TSC after molecular analysis revealed she had inherited the TSC2 c.1832G>A (p.R611Q) mutation from her mother. INTERVENTIONS: The patient received anti-infection therapy, mannitol dehydration, hyperbaric oxygen treatment, and topiramate. OUTCOMES: One month later, the patient was in a decorticate state, presenting with unconsciousness and bilateral arm flexion and leg extension. At 6 weeks, repeated electroencephalography was normal. LESSONS: In addition to the present case report, rare studies have reported cases of TSC presenting as convulsive status epileticus followed by hypoxic cerebropathy, which may be strongly associated with a poor prognosis. Patients with the characteristic skin lesions and epilepsy should be carefully evaluated for the possible diagnosis of TSC.


Assuntos
Hipóxia Encefálica/diagnóstico , Hipóxia Encefálica/etiologia , Estado Epiléptico/complicações , Estado Epiléptico/diagnóstico , Esclerose Tuberosa/complicações , Esclerose Tuberosa/diagnóstico , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Hipóxia Encefálica/genética , Hipóxia Encefálica/terapia , Mutação , Estado Epiléptico/genética , Estado Epiléptico/terapia , Esclerose Tuberosa/genética , Esclerose Tuberosa/terapia , Proteína 2 do Complexo Esclerose Tuberosa/genética
17.
BMC Cancer ; 19(1): 435, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31077186

RESUMO

BACKGROUND: Several subunits of the SWI/SNF chromatin remodeling complex are implicated in both cancer and neurodevelopmental disorders (NDD). Though there is no clinical evidence for an increased tumor risk in individuals with NDDs due to germline mutations in most of these genes so far, this has been repeatedly proposed and discussed. A young woman with NDD due to a de novo mutation in ARID1B now presented with a large renal (> 19 cm in diameter) and multiple hepatic angiomyolipomas (AMLs) but no other signs of tuberous sclerosis complex. METHODS: We analyzed tumor and healthy tissue samples with exome and panel sequencing. RESULTS: Additionally to the previously known, germline ARID1B variant we identified a post-zygotic truncating TSC2 variant in both renal and hepatic AMLs but not in any of the healthy tissues. We did not detect any further, obvious tumor driver events. The identification of a passenger variant in SIPA1L3 in both AMLs points to a common clonal origin. Metastasis of the renal AML into the liver is unlikely on the basis of discordant histopathological features. Our findings therefore point to very low-grade mosaicism for the TSC2 variant, possibly in a yet unknown mesenchymal precursor cell that expanded clonally during tumor development. A possible contribution of the germline ARID1B variant to the tumorigenesis remains unclear but cannot be excluded given the absence of any other evident tumor drivers in the AMLs. CONCLUSION: This unique case highlights the blurred line between tumor genetics and post-zygotic events that can complicate exact molecular diagnoses in patients with rare manifestations. It also demonstrates the relevance of multiple disorders in a single individual, the challenges of detecting low-grade mosaicisms, and the importance of proper diagnosis for treatment and surveillance.


Assuntos
Angiomiolipoma/genética , Deficiência Intelectual/complicações , Neoplasias Renais/genética , Neoplasias Hepáticas/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Proteínas de Ligação a DNA/genética , Feminino , Mutação em Linhagem Germinativa , Humanos , Deficiência Intelectual/genética , Mosaicismo , Fatores de Transcrição/genética , Sequenciamento Completo do Exoma , Adulto Jovem
18.
Toxicol Lett ; 312: 11-21, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31059759

RESUMO

Methamphetamine (METH) is a widely abused illicit psychoactive drug. Our previous study has shown that CCAAT-enhancer binding protein ß (C/EBPß) is an important regulator in METH-induced neuronal autophagy and apoptosis. However, the detailed molecular mechanisms underlying this process remain poorly understood. Previous studies have demonstrated that DNA damage-inducible transcript 4 (DDIT4), Trib3 (tribbles pseudo kinase 3), alpha-synuclein (α-syn) are involved in METH-induced dopaminergic neurotoxicity. We hypothesized that C/EBPß is involved in METH-induced DDIT4-mediated neuronal autophagy and Trib3-mediated neuronal apoptosis. We tested our hypothesis by examining the effects of silencing C/EBPß, DDIT4, Trib3 or α-syn with small interfering ribonucleic acid (siRNA) on METH-induced autophagy and apoptosis in the human neuroblastoma SH-SY5Y cells. We also measured the levels of phosphorylated tuberous sclerosis complex 2 (TSC2) protein and Parkin protein level in SH-SY5Y cells. Furthermore, we demonstrated the effect of silencing C/EBPß on METH-caused neurotoxicity in the striatum of rats by injecting LV-shC/EBPß lentivirus using a stereotaxic positioning system. The results showed that METH exposure increased C/EBPß, DDIT4 protein expression. Elevated DDIT4 expression raised up p-TSC2/TSC2 protein expression ratio, inhibited mTOR signaling pathway, activating cell autophagy. We also found that METH exposure increased the expression of Trib3, α-syn, decreased the Parkin protein expression. Lowering levels of Parkin raised up α-syn expression, which initiated mitochondrial apoptosis by down-regulating anti-apoptotic Bcl-2, followed by up-regulation of pro-apoptotic Bax, resulting in translocation of cytochrome c (cyto c), an apoptogenic factor, from the mitochondria to cytoplasm and activation of caspase-dependent pathways. These findings were supported by data showing METH-induced autophagy and apoptosis was significantly inhibited by silencing C/EBPß, DDIT4, Trib3 or α-syn, or by Parkin over-expression. Based on the present data, a novel of mechanism on METH-induced cell toxicity is proposed, METH exposure increased C/EBPß protein expression, triggered DDIT4/TSC2/mTOR signaling pathway, and evoked Trib3/Parkin/α-syn-related mitochondrial apoptotic signaling pathway. Collectively, these results suggest that C/EBPß plays an important role in METH-triggered autophagy and apoptosis and it may be a potential target for therapeutics in METH-caused neurotoxicity.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Estimulantes do Sistema Nervoso Central/toxicidade , Metanfetamina/toxicidade , Neurônios/efeitos dos fármacos , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Linhagem Celular Tumoral , Regulação da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Humanos , Masculino , Neuroblastoma , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
19.
Investig Clin Urol ; 60(3): 148-155, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31098421

RESUMO

Purpose: Multilocular cystic renal neoplasm of low malignant potential (MCRNLMP) and clear cell renal cell carcinoma with cystic change (MCRCC) have different prognoses despite similar histologic characteristics. The aim of this study was to identify differentially mutated genes in resected tumor specimens from patients diagnosed with MCRNLMP and MCRCC using a kidney cancer gene panel. Materials and Methods: Between 2009 and 2016, 13 MCRNLMP and 17 MCRCC cases were selected. Tumor tissues from 5 MCRNLMP and 16 MCRCC cases were subjected to gene sequencing to detect mutations among 88 genes selected from a kidney cancer gene panel after quality control. Fisher's exact test was used to compare gene mutation profiles between the two diseases. Genes were considered to be positive for mutation according to the presence of an in-frame/frameshift deletion or insertion, missense/nonsense mutation, or multi-hit mutation. Results: During a median follow-up period of 66.2 months, there was only one case of MCRCC recurrence among all 30 patients. Target gene sequencing showed that 35 genes tended to be more frequently positive in either disease group, with six genes showing a significantly different frequency of mutation between the groups: GIGYF2 (odds ratio [OR], 5.735), FGFR3 (OR, 6.787), SETD2 (OR, 4.588), BCR (OR, 6.266), KMT2C (OR, 8.167), and TSC2 (OR, 4.474). Conclusions: Six candidate genes showed significantly different mutation patterns between MCRNLMP and MCRCC, providing insight into their pathogenic mechanisms and differential prognoses.


Assuntos
Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/genética , Neoplasias Renais/diagnóstico , Neoplasias Renais/genética , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/patologia , Proteínas de Transporte/genética , Proteínas de Ligação a DNA/genética , Diagnóstico Diferencial , Feminino , Histona-Lisina N-Metiltransferase/genética , Humanos , Doenças Renais Císticas/patologia , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcr/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Estudos Retrospectivos , Proteína 2 do Complexo Esclerose Tuberosa/genética
20.
Brain Nerve ; 71(4): 374-379, 2019 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-30988224

RESUMO

Tuberous sclerosis complex (TSC) is an autosomal dominant inherited disorders that is characterized by the systemic hamartomas, along with epilepsy, cognitive impairment and hypopigmented macules. It is caused by genetic mutations in either TSC1 or TSC2 gene which encodes hamartin and tuberin, respectively. As the hamartin-tuberin-complex downregulates the mechanistic/mammalian target of the rapamycin complex1 (mTORC1), dysfunction in either hamartin or tuberin induces the constitutive activation of mTORC1. In fact, almost all the symptoms in TSC are derived from the activation of mTORC1. Therefore, mTORC1 inhibitors improves all the symptoms, including skin lesions and neural symptoms. Among the many symptoms, skin lesions appear earlier than renal or pulmonary lesions and are more specific than neuronal symptoms. Therefore, skin lesions are useful for the diagnosis of TSC. This chapter focuses on the features of skin lesions and mechanistic their potential role in differential diagnosis and therapy including the therapeutic use of mTORC1 inhibitors.


Assuntos
Pele/patologia , Esclerose Tuberosa/diagnóstico , Esclerose Tuberosa/patologia , Diagnóstico Diferencial , Epilepsia/patologia , Hamartoma/patologia , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Esclerose Tuberosa/tratamento farmacológico , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética
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