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1.
Cell Death Discov ; 10(1): 149, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514650

RESUMO

Breast Cancer (BC) is one of the most common tumours, and is known for its ability to develop resistance to chemotherapeutic treatments. Autophagy has been linked to chemotherapeutic response in several types of cancer, highlighting its contribution to this process. However, the role of mitophagy, a selective form of autophagy responsible for damaged mitochondria degradation, in the response to therapies in BC is still unclear. In order to address this point, we analysed the role of mitophagy in the treatment of the most common anticancer drug, doxorubicin (DXR), in different models of BC, such as a luminal A subtype-BC cell line MCF7 cells, cultured in 2-Dimension (2D) or in 3-Dimension (3D), and the triple negative BC (TNBC) cell line MDA-MB-231. Through a microarray analysis, we identified a relationship between mitophagy gene expressions related to the canonical PINK1/Parkin-mediated pathway and DXR treatment in BC cells. Afterwards, we demonstrated that the PINK1/Parkin-dependent mitophagy is indeed induced following DXR treatment and that exogenous expression of a small non-coding RNA, the miRNA-218-5p, known to target mRNA of Parkin, was sufficient to inhibit the DXR-mediated mitophagy in MCF7 and in MDA-MB-231 cells, thereby increasing their sensitivity to DXR. Considering the current challenges involved in BC refractory to treatment, our work could provide a promising approach to prevent tumour resistance and recurrence, potentially leading to the development of an innovative approach to combine mitophagy inhibition and chemotherapy.

2.
Neurology ; 101(19): e1933-e1938, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37652704

RESUMO

OBJECTIVES: Different pathophysiologic mechanisms, especially involving astrocytes, could contribute to tuberous sclerosis complex (TSC). We assessed neurodegeneration and astrocytopathy plasma biomarkers in adult patients with TSC to define TSC biomarker profile and investigate clinical-radiologic correlations. METHODS: Patients with TSC aged 15 years or older followed at Policlinico "Umberto I" of Rome were consecutively enrolled (July 2021-June 2022). The plasma levels of the following biomarkers were compared between patients and age/sex-matched healthy controls (HCs): tTau, pTau181, Abeta40, Abeta42, neurofilament light chain, and glial fibrillary acid protein (GFAP). RESULTS: Thirty-one patients (20 females/11 males; median age 30 years, interquartile range 24-47) and 38 HCs were enrolled. Only GFAP was significantly higher in the whole TSC population than in HCs (132.71 [86.14-231.06] vs 44.80 [32.87-66.76] pg/mL, p < 0.001), regardless of genotype. GFAP correlated with the disease clinical (ρ = 0.498, p = 0.005) and radiologic severity (ρ = 0.417, p = 0.001). It was significantly higher in patients with epileptic spasms (254.50 [137.54-432.96] vs 86.92 [47.09-112.76] pg/mL, p < 0.0001), moderate-severe intellectual disability (200.80 [78.40-427.6] vs 105.08 [46.80-152.58] pg/mL, p = 0.040), and autism spectrum disorder (306.26 [159.07-584.47] vs 109.34 [72.56-152.08] pg/mL, p = 0.021). DISCUSSION: Our exploratory study documented a significant increase of GFAP plasma concentration in adult patients with TSC, correlated with their neurologic severity, supporting the central role of astrocytopathy in TSC pathophysiology.


Assuntos
Transtorno do Espectro Autista , Esclerose Tuberosa , Masculino , Feminino , Humanos , Adulto , Transtorno do Espectro Autista/genética , Esclerose Tuberosa/genética , Biomarcadores , Astrócitos , Genótipo , Proteína Glial Fibrilar Ácida/genética
3.
Antioxidants (Basel) ; 11(11)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36358458

RESUMO

Plant-derived polyphenols exhibit beneficial effects on physiological and pathological processes, including cancer and neurodegenerative disorders, mainly because of their antioxidant activity. Apples are highly enriched in these compounds, mainly in their peel. The Tuscia Red (TR) apple variety exhibits the peculiar characteristic of depositing high quantities of polyphenols in the pulp, the edible part of the fruit. Since polyphenols, as any natural product, cannot be considered a panacea per se, in this paper, we propose to assess the biological effects of TR flesh extracts, in comparison with two commercial varieties, in a model system, the insect Drosophila melanogaster, largely recognized as a reliable system to test the in vivo effects of natural and synthetic compounds. We performed a comparative, qualitative and quantitative analysis of the polyphenol compositions of the three cultivars and found that TR flesh shows the highest content of polyphenols, and markedly, anthocyanins. Then, we focused on their effects on a panel of physiological, morphometrical, cellular and behavioral phenotypes in wild-type D. melanogaster. We found that all the apple polyphenol extracts showed dose-dependent effects on most of the phenotypes we considered. Remarkably, all the varieties induced a strong relenting of the cell division rate.

4.
Mol Metab ; 59: 101454, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35150905

RESUMO

OBJECTIVE: Metabolic syndrome, obesity, and steatosis are characterized by a range of dysregulations including defects in ubiquitin ligase tagging proteins for degradation. The identification of novel hepatic genes associated with fatty liver disease and metabolic dysregulation may be relevant to unravelling new mechanisms involved in liver disease progression METHODS: Through integrative analysis of liver transcriptomic and metabolomic obtained from obese subjects with steatosis, we identified itchy E ubiquitin protein ligase (ITCH) as a gene downregulated in human hepatic tissue in relation to steatosis grade. Wild-type or ITCH knockout mouse models of non-alcoholic fatty liver disease (NAFLD) and obesity-related hepatocellular carcinoma were analyzed to dissect the causal role of ITCH in steatosis RESULTS: We show that ITCH regulation of branched-chain amino acids (BCAAs) degradation enzymes is impaired in obese women with grade 3 compared with grade 0 steatosis, and that ITCH acts as a gatekeeper whose loss results in elevation of circulating BCAAs associated with hepatic steatosis. When ITCH expression was specifically restored in the liver of ITCH knockout mice, ACADSB mRNA and protein are restored, and BCAA levels are normalized both in liver and plasma CONCLUSIONS: Our data support a novel functional role for ITCH in the hepatic regulation of BCAA metabolism and suggest that targeting ITCH in a liver-specific manner might help delay the progression of metabolic hepatic diseases and insulin resistance.


Assuntos
Aminoácidos de Cadeia Ramificada , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Obesidade , Ubiquitina-Proteína Ligases , Aminoácidos de Cadeia Ramificada/metabolismo , Animais , Regulação para Baixo , Feminino , Humanos , Camundongos , Camundongos Knockout , Obesidade/complicações , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
5.
Biomedicines ; 9(10)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34680461

RESUMO

Nuclear lamina components have long been regarded as scaffolding proteins, forming a dense fibrillar structure necessary for the maintenance of the nucleus shape in all the animal kingdom. More recently, mutations, aberrant localisation and deregulation of these proteins have been linked to several diseases, including cancer. Using publicly available data we found that the increased expression levels of the nuclear protein Lamin A/C correlate with a reduced overall survival in The Cancer Genome Atlas Research Network (TCGA) patients affected by glioblastoma multiforme (GBM). We show that the expression of the LMNA gene is linked to the enrichment of cancer-related pathways, particularly pathways related to cell adhesion and cell migration. Mimicking the modulation of LMNA in a GBM preclinical cancer model, we confirmed both in vitro and in vivo that the increased expression of LMNA is associated with an increased aggressiveness and tumorigenicity. In addition, delving into the possible mechanism behind LMNA-induced GBM aggressiveness and tumorigenicity, we found that the mTORC2 component, Rictor, plays a central role in mediating these effects.

6.
IEEE/ACM Trans Comput Biol Bioinform ; 17(5): 1582-1594, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30990435

RESUMO

Protein-protein interaction (PPI) network models interconnections between protein-encoding genes. A group of proteins that perform similar functions are often connected to each other in the PPI network. The corresponding genes form pathways or functional modules. Mutation in protein-encoding genes affect behavior of pathways. This results in initiation, progression, and severity of diseases that propagates through pathways. In this work, we integrate mutation, survival information of patients, and PPI network to identify connected subnetworks associated with survival. We define the computational problem using a fitness function called log-rank statistic to score subnetworks. Log-rank statistic compares the survival between two populations. We propose a novel method, Survival Associated Mutated Subnetwork (SAMS) that adopts genetic algorithm strategy to find the connected subnetwork within the PPI network whose mutation yields highest log-rank statistic. We test on real cancer and synthetic datasets. SAMS generate solutions in negligible time while the state-of-art method in literature takes exponential time. Log-rank statistic of SAMS selected mutated subnetworks are comparable to the method. Our result genesets show significant overlap with well-known cancer driver genes derived from curated datasets and studies in literature, display high text-mining score in terms of number of citations combined with disease-specific keywords in PubMed, and identify pathways having high biological relevance.


Assuntos
Algoritmos , Mutação/genética , Neoplasias/genética , Neoplasias/mortalidade , Mapas de Interação de Proteínas/genética , Biologia Computacional/métodos , Variações do Número de Cópias de DNA/genética , Humanos
7.
Cancer Genet ; 238: 50-61, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31425926

RESUMO

Telomere shortening has been supposed to be implicated in both aging and various human diseases especially carcinogenesis process. This phenomenon can lead to a chromosomal instability, contributing to a cell immortalization and tumor induction. In our study, we analyzed the role of telomere shortening in cancer progression, in Tunisian patients with digestive cancer. We measured the absolute telomere length in tumoral vs healthy adjacent tissues of each patient by using a q-RT PCR method and we investigated the relationship between telomere length and various sociodemographic and clinical parameters such as age, sex, tumor stage. In this pathological situation, we observed that, starting from 60 years of age, the telomere length increases in healthy mucosa and that in both healthy and cancer tissues, patients under 60 years have shorter telomeres, suggesting the telomere lengthening becomes more active with age. Finally, a positive correlation between normal and cancer tissues in both non-metastatic and metastatic stages, indicates telomere length in cancer tissue depends essentially on tumor stages. Our data allow us to suggest that telomere length depends on sex and age in healthy tissue while shortening and lengthening fluctuates considerably according to the tumor stage.


Assuntos
Neoplasias/patologia , Telômero , Biomarcadores Tumorais/metabolismo , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Neoplasias/metabolismo , Prognóstico
8.
Acta Diabetol ; 56(12): 1265-1274, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31292722

RESUMO

AIM: Obesity and low-grade inflammation are associated with an increased risk of hepatocellular carcinoma (HCC), a leading cause of cancer-related death worldwide. The tissue inhibitor of metalloproteinase (TIMP) 3, an endogenous inhibitor of protease activity that represents a key mediator of inflammation, is reduced in inflammatory metabolic disorders and cancer. In contrast, Timp3-deficient mice (Timp3-/-) are highly resistant to developing HCC in response to a diethylnitrosamine (DEN); therefore, we aimed to elucidate the biological role of genetic loss of Timp3 in obesity-related hepatocarcinogenesis. METHODS: Fourteen-day-old male wild-type (wt) and Timp3-/- mice were injected with 25 mg/kg DEN or an equal volume of saline. After 4 weeks, mice were randomized into two dietary groups and fed either normal or high-fat diet and allowed to grow until 32 weeks of age. Liver histological features were analyzed, and differentially expressed genes in the liver were quantified. RESULTS: In Timp3-/- mice fed with the obesogenic diet, despite the increase in liver steatosis and inflammation, both the number of tumors and the total tumor size are significantly reduced 30 weeks post-DEN injection, compared to control mice. Moreover, Timp3 deletion in hepatocarcinogenesis during obesity is associated with a reduction in FoxM1 transcriptional activity through H19/miR-675/p53 pathway. CONCLUSIONS: This study suggests that Timp3 ablation leads to cell cycle perturbation, at least in part by repressing FoxM1 transcriptional activity through H19/miR-675/p53 pathway.


Assuntos
Carcinoma Hepatocelular/patologia , Dieta Hiperlipídica/efeitos adversos , Neoplasias Hepáticas/patologia , Obesidade/etiologia , Inibidor Tecidual de Metaloproteinase-3/genética , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/genética , Dietilnitrosamina , Progressão da Doença , Fígado Gorduroso/etiologia , Fígado Gorduroso/genética , Fígado Gorduroso/patologia , Proteína Forkhead Box M1/metabolismo , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Obesidade/patologia , Transdução de Sinais/genética
9.
Stem Cells ; 37(9): 1223-1237, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31132299

RESUMO

The role of proNGF, the precursor of nerve growth factor (NGF), in the biology of adult neural stem cells (aNSCs) is still unclear. Here, we analyzed adult hippocampal neurogenesis in AD11 transgenic mice, in which the constitutive expression of anti-NGF antibody leads to an imbalance of proNGF over mature NGF. We found increased proliferation of progenitors but a reduced neurogenesis in the AD11 dentate gyrus (DG)-hippocampus (HP). Also in vitro, AD11 hippocampal neural stem cells (NSCs) proliferated more, but were unable to differentiate into morphologically mature neurons. By treating wild-type hippocampal progenitors with the uncleavable form of proNGF (proNGF-KR), we demonstrated that proNGF acts as mitogen on aNSCs at low concentration. The mitogenic effect of proNGF was specifically addressed to the radial glia-like (RGL) stem cells through the induction of cyclin D1 expression. These cells express high levels of p75NTR , as demonstrated by immunofluorescence analyses performed ex vivo on RGL cells isolated from freshly dissociated HP-DG or selected in vitro from NSCs by leukemia inhibitory factor. Clonogenic assay performed in the absence of mitogens showed that RGLs respond to proNGF-KR by reactivating their proliferation and thus leading to neurospheres formation. The mitogenic effect of proNGF was further exploited in the expansion of mouse-induced neural stem cells (iNSCs). Chronic exposure of iNSCs to proNGF-KR increased their proliferation. Altogether, we demonstrated that proNGF acts as mitogen on hippocampal and iNSCs. Stem Cells 2019;37:1223-1237.


Assuntos
Giro Denteado/citologia , Hipocampo/citologia , Mitógenos/farmacologia , Fator de Crescimento Neural/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Precursores de Proteínas/farmacologia , Animais , Anticorpos/genética , Anticorpos/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fator Inibidor de Leucemia/farmacologia , Camundongos Transgênicos , Fator de Crescimento Neural/imunologia , Fator de Crescimento Neural/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Precursores de Proteínas/imunologia , Precursores de Proteínas/metabolismo
10.
PLoS One ; 13(4): e0194803, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29649237

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease of unknown cause characterized by alveolar epithelial damage, patchy interstitial fibrosis and diffuse microvascular abnormalities. In IPF, alveolar clustering of iron-laden alveolar macrophages-a common sign of microhemorrhage, has been associated with vascular abnormalities and worsening of pulmonary hypertension. As iron-dependent ROS generation has been shown to induce unrestrained macrophage activation in disease models of vascular damage, we explored alveolar macrophage activation phenotype in IPF patients (n = 16) and healthy controls (CTR, n = 7) by RNA sequencing of bronchoalveolar lavage (BAL) cells. The frequencies of macrophages in BAL cells were 86+4% and 83.4+8% in IPF and CTR groups, respectively (p-value = 0.41). In IPF patients, BAL cells showed increased iron-dependent ROS generation (p-value<0.05 vs CTR). Gene expression analysis showed overrepresentation of Gene Ontology processes/functions and KEGG pathways enriched in upregulated M1-type inflammatory (p-value<0.01), M2-type anti-inflammatory/tissue remodeling (p-value<0.0001), and MTPP-type chronic inflammatory/angiogenic (p-value<0.0001) chemokine and cytokine genes. The ex vivo finding was confirmed by the induction of iron-dependent ROS generation and chemokine/cytokine overexpression of Ccl4, Cxcl10 (M1), Il1rn (M2), Cxcl2, and Cxcl7 (MTPP) in MH-S murine immortalized alveolar macrophages exposed to ferric ammonium citrate in culture (p-value<0.05 vs CTR). The data show alveolar macrophage expression of a pro-inflammatory, tissue remodeling and angiogenic complex activation pattern, suggesting that iron accumulation may play a role in macrophage activation.


Assuntos
Líquido da Lavagem Broncoalveolar/citologia , Fibrose Pulmonar Idiopática/metabolismo , Inflamação/metabolismo , Ferro/metabolismo , Macrófagos/metabolismo , Neovascularização Patológica , Adulto , Idoso , Quimiocinas/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Análise de Sequência de RNA
11.
Stem Cell Reports ; 10(3): 1016-1029, 2018 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-29456186

RESUMO

The capability of generating neural precursor cells with distinct types of regional identity in vitro has recently opened new opportunities for cell replacement in animal models of neurodegenerative diseases. By manipulating Wnt and BMP signaling, we steered the differentiation of mouse embryonic stem cells (ESCs) toward isocortical or hippocampal molecular identity. These two types of cells showed different degrees of axonal outgrowth and targeted different regions when co-transplanted in healthy or lesioned isocortex or in hippocampus. In hippocampus, only precursor cells with hippocampal molecular identity were able to extend projections, contacting CA3. Conversely, isocortical-like cells were capable of extending long-range axonal projections only when transplanted in motor cortex, sending fibers toward both intra- and extra-cortical targets. Ischemic damage induced by photothrombosis greatly enhanced the capability of isocortical-like cells to extend far-reaching projections. Our results indicate that neural precursors generated by ESCs carry intrinsic signals specifying axonal extension in different environments.


Assuntos
Hipocampo/fisiologia , Córtex Motor/fisiologia , Células-Tronco Embrionárias Murinas/fisiologia , Neocórtex/fisiologia , Neurônios/fisiologia , Animais , Axônios/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Camundongos , Neurogênese/fisiologia , Transplante/métodos
12.
Oncotarget ; 8(13): 21692-21709, 2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28423511

RESUMO

The efficacy of Ataxia-Telangiectasia Mutated (ATM) kinase signalling inhibition in cancer therapy is tempered by the identification of new emerging functions of ATM, which suggests that the role of this protein in cancer progression is complex. We recently demonstrated that this tumor suppressor gene could act as tumor promoting factor in HER2 (Human Epidermal Growth Factor Receptor 2) positive breast cancer. Herein we put in evidence that ATM expression sustains the proportion of cells with a stem-like phenotype, measured as the capability to form mammospheres, independently of HER2 expression levels. Transcriptomic analyses revealed that, in mammospheres, ATM modulates the expression of cell cycle-, DNA repair- and autophagy-related genes. Among these, the silencing of the autophagic gene, autophagy related 4C cysteine peptidase (ATG4C), impairs mammosphere formation similarly to ATM depletion. Conversely, ATG4C ectopic expression in cells silenced for ATM expression, rescues mammospheres growth. Finally, tumor array analyses, performed using public data, identify a significant correlation between ATM and ATG4C expression levels in all human breast cancer subtypes, except for the basal-like one.Overall, we uncover a new connection between ATM kinase and autophagy regulation in breast cancer. We demonstrate that, in breast cancer cells, ATM and ATG4C are essential drivers of mammosphere formation, suggesting that their targeting may improve current approaches to eradicate breast cancer cells with a stem-like phenotype.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Relacionadas à Autofagia/biossíntese , Autofagia , Neoplasias da Mama/patologia , Cisteína Endopeptidases/biossíntese , Células-Tronco Neoplásicas/patologia , Autofagia/fisiologia , Western Blotting , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Células-Tronco Neoplásicas/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase
13.
PLoS One ; 12(3): e0172399, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28253359

RESUMO

The DNA repair protein Cockayne syndrome group B (CSB) has been recently identified as a promising anticancer target. Suppression, by antisense technology, of this protein causes devastating effects on tumor cells viability, through a massive induction of apoptosis, while being non-toxic to non-transformed cells. To gain insights into the mechanisms underlying the pro-apoptotic effects observed after CSB ablation, global gene expression patterns were determined, to identify genes that were significantly differentially regulated as a function of CSB expression. Our findings revealed that response to endoplasmic reticulum stress and response to unfolded proteins were ranked top amongst the cellular processes affected by CSB suppression. The major components of the endoplasmic reticulum stress-mediated apoptosis pathway, including pro-apoptotic factors downstream of the ATF3-CHOP cascade, were dramatically up-regulated. Altogether our findings add new pieces to the understanding of CSB mechanisms of action and to the molecular basis of CS syndrome.


Assuntos
Apoptose/genética , DNA Helicases/deficiência , DNA Helicases/genética , Enzimas Reparadoras do DNA/deficiência , Enzimas Reparadoras do DNA/genética , Estresse do Retículo Endoplasmático/genética , Inativação Gênica , Regulação Neoplásica da Expressão Gênica/genética , Células HeLa , Humanos , Proteínas de Ligação a Poli-ADP-Ribose
14.
Mol Cancer ; 16(1): 55, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28270148

RESUMO

BACKGROUND: Many tumor-related factors have shown the ability to affect metabolic pathways by paving the way for cancer-specific metabolic features. Here, we investigate the regulation of mTORC1 by MDM4, a p53-inhibitor with oncogenic or anti-survival activities depending on cell growth conditions. METHOD: MDM4-mTOR relationship was analysed through experiments of overexpression or silencing of endogenous proteins in cell culture and using purified proteins in vitro. Data were further confirmed in vivo using a transgenic mouse model overexpressing MDM4. Additionally, the Cancer Genome Atlas (TCGA) database (N = 356) was adopted to analyze the correlation between MDM4 and mTOR levels and 3D cultures were used to analyse the p53-independent activity of MDM4. RESULTS: Following nutrient deprivation, MDM4 impairs mTORC1 activity by binding and inhibiting the kinase mTOR, and contributing to maintain the cytosolic inactive pool of mTORC1. This function is independent of p53. Inhibition of mTORC1 by MDM4 results in reduced phosphorylation of the mTOR downstream target p70S6K1 both in vitro and in vivo in a MDM4-transgenic mouse. Consistently, MDM4 reduces cell size and proliferation, two features controlled by p70S6K1, and, importantly, inhibits mTORC1-mediated mammosphere formation. Noteworthy, MDM4 transcript levels are significantly reduced in breast tumors characterized by high mTOR levels. CONCLUSION: Overall, these data identify MDM4 as a nutrient-sensor able to inhibit mTORC1 and highlight its metabolism-related tumor-suppressing function.


Assuntos
Complexos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Ciclo Celular , Proteínas de Ciclo Celular , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Neoplasias/genética , Neoplasias/metabolismo , Proteínas Nucleares/genética , Fosforilação , Ligação Proteica , Proteínas Proto-Oncogênicas/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais
15.
Mol Neurobiol ; 54(5): 3729-3744, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27221609

RESUMO

The mouse neuroblastoma N18TG2 clone is unable to differentiate and is defective for the enzymes of the biosynthesis of neurotransmitters. The forced expression of choline acetyltransferase (ChAT) in these cells results in the synthesis and release of acetylcholine (Ach) and hence in the expression of neurospecific features and markers. To understand how the expression of ChAT triggered neuronal differentiation, we studied the differences in genome-wide transcription profiles between the N18TG2 parental cells and its ChAT-expressing 2/4 derived clone. The engagement of the 2/4 cells in the neuronal developmental program was confirmed by the increase of the expression level of several differentiation-related genes and by the reduction of the amount of transcripts of cell cycle genes. At the same time, we observed a massive reorganization of cytoskeletal proteins in terms of gene expression, with the accumulation of the nucleoskeletal lamina component Lamin A/C in differentiating cells. The increase of the Lmna transcripts induced by ChAT expression in 2/4 cells was mimicked treating the parental N18TG2 cells with the acetylcholine receptor agonist carbachol, thus demonstrating the direct role played by this receptor in neuron nuclei maturation. Conversely, a treatment of 2/4 cells with the muscarinic receptor antagonist atropine resulted in the reduction of the amount of Lmna RNA. Finally, the hypothesis that Lmna gene product might play a crucial role in the ChAT-dependent molecular differentiation cascade was strongly supported by Lmna knockdown in 2/4 cells leading to the downregulation of genes involved in differentiation and cytoskeleton formation and to the upregulation of genes known to regulate self-renewal and stemness.


Assuntos
Diferenciação Celular , Colina O-Acetiltransferase/metabolismo , Lamina Tipo A/metabolismo , Neuroblastoma/enzimologia , Neuroblastoma/patologia , Animais , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Ontologia Genética , Camundongos , Neuroblastoma/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Mapeamento de Interação de Proteínas , Receptores Colinérgicos/metabolismo , Receptores Muscarínicos/metabolismo , Transcrição Gênica/efeitos dos fármacos , Tretinoína/farmacologia , Regulação para Cima/efeitos dos fármacos
16.
Cancer Res ; 75(21): 4560-72, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26359458

RESUMO

Restoration of wild-type p53 tumor suppressor function has emerged as an attractive anticancer strategy. Therapeutics targeting the two p53-negative regulators, MDM2 and MDM4, have been developed, but most agents selectively target the ability of only one of these molecules to interact with p53, leaving the other free to operate. Therefore, we developed a method that targets the activity of MDM2 and MDM4 simultaneously based on recent studies indicating that formation of MDM2/MDM4 heterodimer complexes are required for efficient inactivation of p53 function. Using computational and mutagenesis analyses of the heterodimer binding interface, we identified a peptide that mimics the MDM4 C-terminus, competes with endogenous MDM4 for MDM2 binding, and activates p53 function. This peptide induces p53-dependent apoptosis in vitro and reduces tumor growth in vivo. Interestingly, interfering with the MDM2/MDM4 heterodimer specifically activates a p53-dependent oxidative stress response. Consistently, distinct subcellular pools of MDM2/MDM4 complexes were differentially sensitive to the peptide; nuclear MDM2/MDM4 complexes were particularly highly susceptible to the peptide-displacement activity. Taken together, these data identify the MDM2/MDM4 interaction interface as a valuable molecular target for therapeutic reactivation of p53 oncosuppressive function.


Assuntos
Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Proteínas Nucleares/metabolismo , Peptídeos/uso terapêutico , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/fisiologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Células HCT116 , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Knockout , Camundongos Nus , Estresse Oxidativo/fisiologia , Ligação Proteica/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Ubiquitinação
17.
BMC Neurosci ; 15: 48, 2014 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-24713110

RESUMO

BACKGROUND: Growing evidence shows that, in vivo, the precursor of Nerve Growth Factor (NGF), proNGF, displays biological activities different from those of its mature NGF counterpart, mediated by distinct, and somewhat complementary, receptor binding properties. NGF and proNGF induce distinct transcriptional signatures in target cells, highlighting their different bioactivities. In vivo, proNGF and mature NGF coexist. It was proposed that the relative proNGF/NGF ratio is important for their biological outcomes, especially in pathological conditions, since proNGF, the principal form of NGF in Central Nervous System (CNS), is increased in Alzheimer's disease brains. These observations raise a relevant question: does proNGF, in the presence of NGF, influence the NGF transcriptional response and viceversa? In order to understand the specific proNGF effect on NGF activity, depending on the relative proNGF/NGF concentration, we investigated whether proNGF affects the pattern of well-known NGF-regulated mRNAs. RESULTS: To test any influence of proNGF on pure NGF expression fingerprinting, the expression level of a set of candidate genes was analysed by qReal-Time PCR in rat adrenal pheochromocytoma cell line PC12, treated with a mixture of NGF and proNGF recombinant proteins, in different stoichiometric ratios. These candidates were selected amongst a set of genes well-known as being rapidly induced by NGF treatment. We found that, when PC12 cells are treated with proNGF/NGF mixtures, a unique pattern of gene expression, which does not overlap with that deriving from treatment with either proNGF or NGF alone, is induced. The specific effect is also dependent on the stoichiometric composition of the mixture. The proNGF/NGF equimolar mixture seems to partially neutralize the specific effects of the proNGF or NGF individual treatments, showing a weaker overall response, compared to the individual contributions of NGF and proNGF alone. CONCLUSIONS: Using gene expression as a functional read-out, our data demonstrate that the relative availability of NGF and proNGF in vivo might modulate the biological outcome of these ligands.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/metabolismo , Fator de Crescimento Neural/metabolismo , Precursores de Proteínas/metabolismo , Animais , Células PC12 , Ratos
18.
J Cell Physiol ; 229(4): 463-70, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24105779

RESUMO

Cervical carcinoma represents the paradigm of virus-induced cancers, where virtually all cervical cancers come from previous "high-risk" HPV infection. The persistent expression of the HPV viral oncoproteins E6 and E7 is responsible for the reprogramming of fundamental cellular functions in the host cell, thus generating a noticeable, yet only partially explored, imbalance in protein molecular networks and cell signaling pathways. Eighty-eight cellular factors, identified as HPV direct or surrogate targets, were chosen and monitored in a retrospective analysis for their mRNA expression in HPV-induced cervical lesions, from dysplasia to cancer. Real-time quantitative PCR (qPCR) was performed by using formalin-fixed, paraffin embedded archival samples. Gene expression analysis identified 40 genes significantly modulated in LSIL, HSIL, and squamous cervical carcinoma. Interestingly, among these, the expression level of a panel of four genes, TOP2A, CTNNB1, PFKM, and GSN, was able to distinguish between normal tissues and cervical carcinomas. Immunohistochemistry was also done to assess protein expression of two genes among those up-regulated during the transition between dysplasia and carcinoma, namely E2F1 and CDC25A, and their correlation with clinical parameters. Besides the possibility of significantly enhancing the use of some of these factors in diagnostic or prognostic procedures, these data clearly outline specific pathways, and thus key biological processes, altered in cervical dysplasia and carcinoma. Deeper insight on how these molecular mechanisms work may help widen the spectrum of novel innovative approaches to these virus-induced cell pathologies.


Assuntos
Carcinoma/metabolismo , Carcinoma/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/virologia , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Infecções por Papillomavirus/metabolismo , RNA Viral/isolamento & purificação , Fator de Transcrição STAT1 , Transcriptoma , Regulação para Cima
19.
EMBO Mol Med ; 5(3): 441-55, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23401241

RESUMO

ADAM17 and its inhibitor TIMP3 are involved in nephropathy, but their role in diabetic kidney disease (DKD) is unclear. Diabetic Timp3(-/-) mice showed increased albuminuria, increased membrane thickness and mesangial expansion. Microarray profiling uncovered a significant reduction of Foxo1 expression in diabetic Timp3(-/-) mice compared to WT, along with FoxO1 target genes involved in autophagy, while STAT1, a repressor of FoxO1 transcription, was increased. Re-expression of Timp3 in Timp3(-/-) mesangial cells rescued the expression of Foxo1 and its targets, and decreased STAT1 expression to control levels; abolishing STAT1 expression led to a rescue of FoxO1, evoking a role of STAT1 in linking Timp3 deficiency to FoxO1. Studies on kidney biopsies from patients with diabetic nephropathy confirmed a significant reduction in TIMP3, FoxO1 and FoxO1 target genes involved in autophagy compared to controls, while STAT1 expression was strongly increased. Our study suggests that loss of TIMP3 is a hallmark of DKD in human and mouse models and designates TIMP3 as a new possible therapeutic target for diabetic nephropathy.


Assuntos
Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/etiologia , Fatores de Transcrição Forkhead/metabolismo , Glomérulos Renais/metabolismo , Fator de Transcrição STAT1/metabolismo , Inibidor Tecidual de Metaloproteinase-3/deficiência , Albuminúria/etiologia , Albuminúria/metabolismo , Animais , Autofagia , Biópsia , Linhagem Celular , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Glomérulos Renais/patologia , Células Mesangiais/metabolismo , Camundongos , Camundongos Knockout , Cultura Primária de Células , Interferência de RNA , Fator de Transcrição STAT1/genética , Transdução de Sinais , Inibidor Tecidual de Metaloproteinase-3/genética , Transfecção
20.
Proc Natl Acad Sci U S A ; 110(5): 1935-40, 2013 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-23319656

RESUMO

Endocannabinoid, particularly 2-arachidonoyl glycerol (2-AG), signaling has recently emerged as a molecular determinant of neuronal migration and synapse formation during cortical development. However, the cell type specificity and molecular regulation of spatially and temporally confined morphogenic 2-AG signals remain unexplored. Here, we demonstrate that genetic and pharmacological manipulation of CB(1) cannabinoid receptors permanently alters cholinergic projection neuron identity and hippocampal innervation. We show that nerve growth factor (NGF), implicated in the morphogenesis and survival of cholinergic projection neurons, dose-dependently and coordinately regulates the molecular machinery for 2-AG signaling via tropomyosine kinase A receptors in vitro. In doing so, NGF limits the sorting of monoacylglycerol lipase (MGL), rate limiting 2-AG bioavailability, to proximal neurites, allowing cell-autonomous 2-AG signaling at CB(1) cannabinoid receptors to persist at atypical locations to induce superfluous neurite extension. We find that NGF controls MGL degradation in vitro and in vivo and identify the E3 ubiquitin ligase activity of breast cancer type 1 susceptibility protein (BRCA1) as a candidate facilitating MGL's elimination from motile neurite segments, including growth cones. BRCA1 inactivation by cisplatin or genetically can rescue and reposition MGL, arresting NGF-induced growth responses. These data indicate that NGF can orchestrate endocannabinoid signaling to promote cholinergic differentiation and implicate BRCA1 in determining neuronal morphology.


Assuntos
Endocanabinoides/metabolismo , Monoacilglicerol Lipases/metabolismo , Fator de Crescimento Neural/farmacologia , Neurônios/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Ácidos Araquidônicos/metabolismo , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Perfilação da Expressão Gênica , Glicerídeos/metabolismo , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Immunoblotting , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , Monoacilglicerol Lipases/genética , Neurônios/metabolismo , Células PC12 , Ratos , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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