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1.
Stem Cells ; 42(1): 42-54, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-37798139

RESUMO

Bone marrow microenvironmental stimuli profoundly impact hematopoietic stem cell fate and biology. As G protein-coupled receptors, the bitter taste receptors (TAS2Rs) are key in transmitting extracellular stimuli into an intracellular response, within the oral cavity but also in extraoral tissues. Their expression in the bone marrow (BM)-derived cells suggests their involvement in sensing the BM microenvironmental fluctuation. In the present study, we demonstrated that umbilical cord blood (UCB)-derived CD34+ cells express fully functional TAS2Rs along with the signal transduction cascade components and their activation by the prototypical agonist, denatonium benzoate, significantly modulated genes involved in stemness maintenance and regulation of cell trafficking. The activation of these specific pathways was confirmed in functional in vitro experiments. Denatonium exposure exerted an antiproliferative effect on UCB-derived CD34+ cells, mainly affecting the most undifferentiated progenitor frequency. It also reduced their clonogenicity and repopulating potential in vitro. In addition, the TAS2R signaling activation impaired the UCB-derived CD34+ cell trafficking, mainly reducing the migration toward the chemoattractant agent CXCL12 and modulating the expression of the adhesion molecules CD62L, CD49d, and CD29. In conclusion, our results in UCB-derived CD34+ cells expand the observation of TAS2R expression in the setting of BM-resident cells and shed light on the role of TAS2Rs in the extrinsic regulation of hematopoietic stem cell functions.


Assuntos
Células-Tronco Hematopoéticas , Paladar , Células-Tronco Hematopoéticas/metabolismo , Compostos de Amônio Quaternário/farmacologia , Compostos de Amônio Quaternário/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Antígenos CD34/metabolismo
2.
Cell Mol Life Sci ; 79(2): 126, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35132494

RESUMO

B-type lamins are fundamental components of the nuclear lamina, a complex structure that acts as a scaffold for organization and function of the nucleus. Lamin B1 and B2, the most represented isoforms, are encoded by LMNB1 and LMNB2 gene, respectively. All B-type lamins are synthesized as precursors and undergo sequential post-translational modifications to generate the mature protein. B-type lamins are involved in a wide range of nuclear functions, including DNA replication and repair, regulation of chromatin and nuclear stiffness. Moreover, lamins B1 and B2 regulate several cellular processes, such as tissue development, cell cycle, cellular proliferation, senescence, and DNA damage response. During embryogenesis, B-type lamins are essential for organogenesis, in particular for brain development. As expected from the numerous and pivotal functions of B-type lamins, mutations in their genes or fluctuations in their expression levels are critical for the onset of several diseases. Indeed, a growing range of human disorders have been linked to lamin B1 or B2, increasing the complexity of the group of diseases collectively known as laminopathies. This review highlights the recent findings on the biological role of B-type lamins under physiological or pathological conditions, with a particular emphasis on brain disorders and cancer.


Assuntos
Encefalopatias/metabolismo , Lamina Tipo B/fisiologia , Laminopatias/metabolismo , Neoplasias/metabolismo , Animais , Humanos
3.
Cell Mol Life Sci ; 79(4): 195, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35303162

RESUMO

Glioblastoma represents the most lethal brain tumor in adults. Several studies have shown the key role of phospholipase C ß1 (PLCß1) in the regulation of many mechanisms within the central nervous system suggesting PLCß1 as a novel signature gene in the molecular classification of high-grade gliomas. This study aims to determine the pathological impact of PLCß1 in glioblastoma, confirming that PLCß1 gene expression correlates with glioma's grade, and it is lower in 50 glioblastoma samples compared to 20 healthy individuals. PLCß1 silencing in cell lines and primary astrocytes, leads to increased cell migration and invasion, with the increment of mesenchymal transcription factors and markers, as Slug and N-Cadherin and metalloproteinases. Cell proliferation, through increased Ki-67 expression, and the main survival pathways, as ß-catenin, ERK1/2 and Stat3 pathways, are also affected by PLCß1 silencing. These data suggest a potential role of PLCß1 in maintaining a normal or less aggressive glioma phenotype.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Proliferação de Células/genética , Glioblastoma/patologia , Glioma/patologia , Humanos , Fosfolipase C beta/genética , Fosfolipase C beta/metabolismo
4.
Int J Mol Sci ; 24(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37685903

RESUMO

Phospholipase C (PLC) enzymes represent crucial participants in the plasma membrane of mammalian cells, including the cardiac sarcolemmal (SL) membrane of cardiomyocytes. They are responsible for the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) into 1,2-diacylglycerol (DAG) and inositol (1,4,5) trisphosphate (Ins(1,4,5)P3), both essential lipid mediators. These second messengers regulate the intracellular calcium (Ca2+) concentration, which activates signal transduction cascades involved in the regulation of cardiomyocyte activity. Of note, emerging evidence suggests that changes in cardiomyocytes' phospholipid profiles are associated with an increased occurrence of cardiovascular diseases, but the underlying mechanisms are still poorly understood. This review aims to provide a comprehensive overview of the significant impact of PLC on the cardiovascular system, encompassing both physiological and pathological conditions. Specifically, it focuses on the relevance of PLCß isoforms as potential cardiac biomarkers, due to their implications for pathological disorders, such as cardiac hypertrophy, diabetic cardiomyopathy, and myocardial ischemia/reperfusion injury. Gaining a deeper understanding of the mechanisms underlying PLCß activation and regulation is crucial for unraveling the complex signaling networks involved in healthy and diseased myocardium. Ultimately, this knowledge holds significant promise for advancing the development of potential therapeutic strategies that can effectively target and address cardiac disorders by focusing on the PLCß subfamily.


Assuntos
Cardiopatias , Isoenzimas , Animais , Humanos , Fosfolipase C beta , Miócitos Cardíacos , Biomarcadores , Mamíferos
5.
Cell Mol Life Sci ; 78(6): 2781-2795, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33034697

RESUMO

Autosomal-dominant leukodystrophy (ADLD) is a rare fatal neurodegenerative disorder with overexpression of the nuclear lamina component, Lamin B1 due to LMNB1 gene duplication or deletions upstream of the gene. The molecular mechanisms responsible for driving the onset and development of this pathology are not clear yet. Vacuolar demyelination seems to be one of the most significant histopathological observations of ADLD. Considering the role of oligodendrocytes, astrocytes, and leukemia inhibitory factor (LIF)-activated signaling pathways in the myelination processes, this work aims to analyze the specific alterations in different cell populations from patients with LMNB1 duplications and engineered cellular models overexpressing Lamin B1 protein. Our results point out, for the first time, that astrocytes may be pivotal in the evolution of the disease. Indeed, cells from ADLD patients and astrocytes overexpressing LMNB1 show severe ultrastructural nuclear alterations, not present in oligodendrocytes overexpressing LMNB1. Moreover, the accumulation of Lamin B1 in astrocytes induces a reduction in LIF and in LIF-Receptor (LIF-R) levels with a consequential decrease in LIF secretion. Therefore, in both our cellular models, Jak/Stat3 and PI3K/Akt axes, downstream of LIF/LIF-R, are downregulated. Significantly, the administration of exogenous LIF can partially reverse the toxic effects induced by Lamin B1 accumulation with differences between astrocytes and oligodendrocytes, highlighting that LMNB1 overexpression drastically affects astrocytic function reducing their fundamental support to oligodendrocytes in the myelination process. In addition, inflammation has also been investigated, showing an increased activation in ADLD patients' cells.


Assuntos
Astrócitos/metabolismo , Doenças Desmielinizantes/patologia , Lamina Tipo B/metabolismo , Transdução de Sinais , Astrócitos/citologia , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Células Cultivadas , Doenças Desmielinizantes/metabolismo , Regulação para Baixo/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Mediadores da Inflamação/metabolismo , Lamina Tipo B/genética , Fator Inibidor de Leucemia/metabolismo , Fator Inibidor de Leucemia/farmacologia , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Receptores de OSM-LIF/metabolismo , Regulação para Cima/efeitos dos fármacos
6.
FASEB J ; 34(11): 15400-15416, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32959428

RESUMO

MDS are characterized by anemia and transfusion requirements. Transfused patients frequently show iron overload that negatively affects hematopoiesis. Iron chelation therapy can be effective in these MDS cases, but the molecular consequences of this treatment need to be further investigated. That is why we studied the molecular features of iron effect and Deferasirox therapy on PI-PLCbeta1 inositide signaling, using hematopoietic cells and MDS samples. At baseline, MDS patients showing a positive response after iron chelation therapy displayed higher levels of PI-PLCbeta1/Cyclin D3/PKCalpha expression. During treatment, these responder patients, as well as hematopoietic cells treated with FeCl3 and Deferasirox, showed a specific reduction of PI-PLCbeta1/Cyclin D3/PKCalpha expression, indicating that this signaling pathway is targeted by Deferasirox. The treatment was also able to specifically decrease the production of ROS. This effect correlated with a reduction of IL-1A and IL-2, as well as Akt/mTOR phosphorylation. In contrast, cells exposed only to FeCl3 and cells from MDS patients refractory to Deferasirox showed a specific increase of ROS and PI-PLCbeta1/Cyclin D3/PKCalpha expression. All in all, our data show that PI-PLCbeta1 signaling is a target for iron-induced oxidative stress and suggest that baseline PI-PLCbeta1 quantification could predict iron chelation therapy response in MDS.


Assuntos
Ciclina D3/metabolismo , Sobrecarga de Ferro/complicações , Ferro/efeitos adversos , Síndromes Mielodisplásicas/terapia , Estresse Oxidativo/efeitos dos fármacos , Fosfolipase C beta/metabolismo , Proteína Quinase C-alfa/metabolismo , Idoso , Transfusão de Sangue/estatística & dados numéricos , Ciclina D3/genética , Deferasirox/farmacologia , Feminino , Regulação da Expressão Gênica , Humanos , Quelantes de Ferro/farmacologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/patologia , Fosfolipase C beta/genética , Fosforilação , Proteína Quinase C-alfa/genética , Transdução de Sinais
7.
Int J Mol Sci ; 22(2)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467674

RESUMO

Erythropoiesis regulation is essential in normal physiology and pathology, particularly in myelodysplastic syndromes (MDS) and ß-thalassemia. Several signaling transduction processes, including those regulated by inositides, are implicated in erythropoiesis, and the latest MDS or ß-thalassemia preclinical and clinical studies are now based on their regulation. Among others, the main pathways involved are those regulated by transforming growth factor (TGF)-ß, which negatively regulates erythrocyte differentiation and maturation, and erythropoietin (EPO), which acts on the early-stage erythropoiesis. Also small mother against decapentaplegic (SMAD) signaling molecules play a role in pathology, and activin receptor ligand traps are being investigated for future clinical applications. Even inositide-dependent signaling, which is important in the regulation of cell proliferation and differentiation, is specifically associated with erythropoiesis, with phospholipase C (PLC) and phosphatidylinositol 3-kinase (PI3K) as key players that are becoming increasingly important as new promising therapeutic targets. Additionally, Roxadustat, a new erythropoiesis stimulating agent targeting hypoxia inducible factor (HIF), is under clinical development. Here, we review the role and function of the above-mentioned signaling pathways, and we describe the state of the art and new perspectives of erythropoiesis regulation in MDS and ß-thalassemia.


Assuntos
Eritropoese , Síndromes Mielodisplásicas/metabolismo , Transdução de Sinais , Talassemia beta/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Ensaios Clínicos como Assunto , Eritropoetina/metabolismo , Glicina/análogos & derivados , Glicina/farmacologia , Hematínicos/uso terapêutico , Humanos , Fator 1 Induzível por Hipóxia/metabolismo , Isoquinolinas/farmacologia , Ligantes , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fosfolipases Tipo C/metabolismo
8.
Handb Exp Pharmacol ; 259: 291-308, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31889219

RESUMO

Nuclear inositides have a specific subcellular distribution that is linked to specific functions; thus their regulation is fundamental both in health and disease. Emerging evidence shows that alterations in multiple inositide signalling pathways are involved in pathophysiology, not only in cancer but also in other diseases. Here, we give an overview of the main features of inositides in the cell, and we discuss their potential as new molecular therapeutic targets.


Assuntos
Núcleo Celular , Fosfatidilinositóis/fisiologia , Transdução de Sinais , Humanos
9.
Int J Mol Sci ; 21(15)2020 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-32722576

RESUMO

An increasing number of reports suggests a significant involvement of the phosphoinositide (PI) cycle in cancer development and progression. Diacylglycerol kinases (DGKs) are very active in the PI cycle. They are a family of ten members that convert diacylglycerol (DAG) into phosphatidic acid (PA), two-second messengers with versatile cellular functions. Notably, some DGK isoforms, such as DGKα, have been reported to possess promising therapeutic potential in cancer therapy. However, further studies are needed in order to better comprehend their involvement in cancer. In this review, we highlight that DGKs are an essential component of the PI cycle that localize within several subcellular compartments, including the nucleus and plasma membrane, together with their PI substrates and that they are involved in mediating major cancer cell mechanisms such as growth and metastasis. DGKs control cancer cell survival, proliferation, and angiogenesis by regulating Akt/mTOR and MAPK/ERK pathways. In addition, some DGKs control cancer cell migration by regulating the activities of the Rho GTPases Rac1 and RhoA.


Assuntos
Movimento Celular , Diacilglicerol Quinase/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas de Neoplasias/metabolismo , Neoplasias/enzimologia , Animais , Diglicerídeos/metabolismo , Humanos , Neoplasias/patologia
10.
Int J Mol Sci ; 21(7)2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32276377

RESUMO

Phosphoinositides (PI) form just a minor portion of the total phospholipid content in cells but are significantly involved in cancer development and progression. In several cancer types, phosphatidylinositol 3,4,5-trisphosphate [PtdIns(3,4,5)P3] and phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] play significant roles in regulating survival, proliferation, invasion, and growth of cancer cells. Phosphoinositide-specific phospholipase C (PLC) catalyze the generation of the essential second messengers diacylglycerol (DAG) and inositol 1,4,5 trisphosphate (InsP3) by hydrolyzing PtdIns(4,5)P2. DAG and InsP3 regulate Protein Kinase C (PKC) activation and the release of calcium ions (Ca2+) into the cytosol, respectively. This event leads to the control of several important biological processes implicated in cancer. PLCs have been extensively studied in cancer but their regulatory roles in the oncogenic process are not fully understood. This review aims to provide up-to-date knowledge on the involvement of PLCs in cancer. We focus specifically on PLCß, PLCγ, PLCδ, and PLCε isoforms due to the numerous evidence of their involvement in various cancer types.


Assuntos
Neoplasias/enzimologia , Fosfatidilinositóis/metabolismo , Fosfoinositídeo Fosfolipase C/metabolismo , Transdução de Sinais , Animais , Diglicerídeos/metabolismo , Humanos , Neoplasias/metabolismo , Neoplasias/fisiopatologia , Proteína Quinase C/metabolismo
11.
FASEB J ; 32(2): 681-692, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28970249

RESUMO

PI-PLCß1 is involved in cell proliferation, differentiation, and myelodysplastic syndrome (MDS) pathogenesis. Moreover, the increased activity of PI-PLCß1 reduces the expression of PKC-α, which, in turn, delays the cell proliferation and is linked to erythropoiesis. Lenalidomide is currently used in low-risk patients with MDS and del(5q), where it can suppress the del(5q) clone and restore normal erythropoiesis. In this study, we analyzed the effect of lenalidomide on 16 patients with low-risk del(5q) MDS, as well as del(5q) and non-del(5q) hematopoietic cell lines, mainly focusing on erythropoiesis, cell cycle, and PI-PLCß1/PKC-α signaling. Overall, 11 patients were evaluated clinically, and 10 (90%) had favorable responses; the remaining case had a stable disease. At a molecular level, both responder patients and del(5q) cells showed a specific induction of erythropoiesis, with a reduced γ/ß-globin ratio, an increase in glycophorin A, and a nuclear translocation of PKC-α. Moreover, lenalidomide could induce a selective G0/G1 arrest of the cell cycle in del(5q) cells, slowing down the rate proliferation in those cells. Altogether, our results could not only better explain the role of PI-PLCß1/PKC-α signaling in erythropoiesis but also lead to a better comprehension of the lenalidomide effect on del(5q) MDS and pave the way to innovative, targeted therapies.-Poli, A., Ratti, S., Finelli, C., Mongiorgi, S., Clissa, C., Lonetti, A., Cappellini, A., Catozzi, A., Barraco, M., Suh, P.-G., Manzoli, L., McCubrey, J. A., Cocco, L., Follo, M. Y. Nuclear translocation of PKC-α is associated with cell cycle arrest and erythroid differentiation in myelodysplastic syndromes (MDSs).


Assuntos
Diferenciação Celular , Núcleo Celular/enzimologia , Células Eritroides/enzimologia , Eritropoese , Pontos de Checagem da Fase G1 do Ciclo Celular , Síndromes Mielodisplásicas/enzimologia , Proteína Quinase C-alfa/metabolismo , Transdução de Sinais , Transporte Ativo do Núcleo Celular , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular , Núcleo Celular/genética , Núcleo Celular/patologia , Células Eritroides/patologia , Feminino , Humanos , Masculino , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Proteína Quinase C-alfa/genética , Fase de Repouso do Ciclo Celular
12.
J Cell Biochem ; 118(8): 1969-1978, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28106288

RESUMO

The existence of an independent nuclear inositide pathway distinct from the cytoplasmic one has been demonstrated in different physiological systems and in diseases. In this prospect we analyze the role of PI-PLCß1 nuclear isoform in relation to the cell cycle regulation, the cell differentiation, and different physiopathological pathways focusing on the importance of the nuclear localization from both molecular and clinical point of view. PI-PLCß1 is essential for G1/S transition through DAG and Cyclin D3 and plays also a central role in G2/M progression through Cyclin B1 and PKCα. In the differentiation process of C2C12 cells PI-PLCß1 increases in both myogenic differentiation and osteogenic differentiation. PI-PLCß1 and Cyclin D3 reduction has been observed in Myotonic Dystrophy (DM) suggesting a pivotal role of these enzymes in DM physiopathology. PI-PLCß1 is also involved in adipogenesis through a double phase mechanism. Moreover, PI-PLCß1 plays a key role in the normal hematopoietic differentiation where it seems to decrease in erythroid differentiation and increase in myeloid differentiation. In Myelodysplastic Syndromes (MDS) PI-PLCß1 has a genetic and epigenetic relevance and it is related to MDS patients' risk of Acute Myeloid Leukemia (AML) evolution. In MDS patients PI-PLCß1 seems to be also a therapeutic predictive outcome marker. In the central nervous system, PI-PLCß1 seems to be involved in different pathways in both brain cortex development and synaptic plasticity related to different diseases. Another PI-PLC isozyme that could be related to nuclear activities is PI-PLCζ that is involved in infertility processes. J. Cell. Biochem. 118: 1969-1978, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Núcleo Celular/metabolismo , Fosfatos de Inositol/metabolismo , Síndromes Mielodisplásicas/genética , Células Mieloides/metabolismo , Fosfolipase C beta/genética , Adipócitos/metabolismo , Adipócitos/patologia , Animais , Encefalopatias/genética , Encefalopatias/metabolismo , Encefalopatias/patologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/genética , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação da Expressão Gênica , Humanos , Infertilidade/genética , Infertilidade/metabolismo , Infertilidade/patologia , Células Musculares/metabolismo , Células Musculares/patologia , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Células Mieloides/patologia , Distrofia Miotônica/genética , Distrofia Miotônica/metabolismo , Distrofia Miotônica/patologia , Osteoblastos/metabolismo , Osteoblastos/patologia , Fosfolipase C beta/metabolismo , Transdução de Sinais
13.
J Cell Physiol ; 231(8): 1645-55, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26626942

RESUMO

Phosphatidylinositol (PI) metabolism represents the core of a network of signaling pathways which modulate many cellular functions including cell proliferation, cell differentiation, apoptosis, and membrane trafficking. An array of kinases, phosphatases, and lipases acts on PI creating an important number of second messengers involved in different cellular processes. Although, commonly, PI signaling was described to take place at the plasma membrane, many evidences indicated the existence of a PI cycle residing in the nuclear compartment of eukaryotic cells. The discovery of this mechanism shed new light on many nuclear functions, such as gene transcription, DNA modifications, and RNA expression. As these two PI cycles take place independently of one another, understanding how nuclear lipid signaling functions and modulates nuclear output is fundamental in the study of many cellular processes. J. Cell. Physiol. 231: 1645-1655, 2016. © 2015 Wiley Periodicals, Inc.


Assuntos
Núcleo Celular/enzimologia , Fosfatidilinositóis/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Sistemas do Segundo Mensageiro , Fosfolipases Tipo C/metabolismo , Animais , Pontos de Checagem do Ciclo Celular , Diferenciação Celular , Núcleo Celular/patologia , Proliferação de Células , Humanos , Hidrólise , Síndromes Mielodisplásicas/enzimologia , Síndromes Mielodisplásicas/patologia , Neoplasias/enzimologia , Neoplasias/patologia , Fosfatidilinositol 4,5-Difosfato/metabolismo , Transcrição Gênica
14.
Biochem Soc Trans ; 42(5): 1471-6, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25233434

RESUMO

Protein kinases C (PKCs) are a family of serine/threonine kinases which act as key regulators in cell cycle progression and differentiation. Studies of the involvement of PKCs in cell proliferation showed that their role is dependent on cell models, cell cycle phases, timing of activation and localization. Indeed, PKCs can positively and negatively act on it, regulating entry, progression and exit from the cell cycle. In particular, the targets of PKCs resulted to be some of the key proteins involved in the cell cycle including cyclins, cyclin-dependent kinases (Cdks), Cip/Kip inhibitors and lamins. Several findings described roles for PKCs in the regulation of G1/S and G2/M checkpoints. As a matter of fact, data from independent laboratories demonstrated PKC-related modulations of cyclins D, leading to effects on the G1/S transition and differentiation of different cell lines. Moreover, interesting data were published on PKC-mediated phosphorylation of lamins. In addition, PKC isoenzymes can accumulate in the nuclei, attracted by different stimuli including diacylglycerol (DAG) fluctuations during cell cycle progression, and target lamins, leading to their disassembly at mitosis. In the present paper, we briefly review how PKCs could regulate cell proliferation and differentiation affecting different molecules related to cell cycle progression.


Assuntos
Ciclo Celular , Modelos Biológicos , Proteína Quinase C/metabolismo , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Animais , Diferenciação Celular , Núcleo Celular/enzimologia , Núcleo Celular/metabolismo , Proliferação de Células , Ciclina D/genética , Ciclina D/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular , Pontos de Checagem da Fase G2 do Ciclo Celular , Regulação da Expressão Gênica , Humanos , Isoenzimas/química , Isoenzimas/metabolismo , Laminas/metabolismo , Fosforilação , Proteína Quinase C/química , Estrutura Terciária de Proteína , Transporte Proteico
15.
Curr Top Microbiol Immunol ; 362: 235-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23086421

RESUMO

Myelodysplastic syndromes (MDS), clonal hematopoietic stem-cell disorders mainly affecting older adult patients, show ineffective hematopoiesis in one or more of the lineages of the bone marrow. A number of MDS progresses to acute myeloid leukemia (AML) with the involvement of genetic and epigenetic mechanisms affecting PI-PLC ß1. The molecular mechanisms underlying the MDS evolution to AML are still unclear, even though it is now clear that the nuclear signaling elicited by PI-PLC ß1, Cyclin D3, and Akt plays an important role in the control of the balance between cell cycle progression and apoptosis in both normal and pathologic conditions. Moreover, a correlation between other PI-PLCs, such as PI-PLC ß3, kinases and phosphatases has been postulated in MDS pathogenesis. Here, we review the findings hinting at the role of nuclear lipid signaling pathways in MDS, which could become promising therapeutic targets.


Assuntos
Núcleo Celular/enzimologia , Síndromes Mielodisplásicas/etiologia , Fosfatidilinositóis/metabolismo , Fosfolipase C beta/fisiologia , Epigenômica , Humanos , Transdução de Sinais/fisiologia
16.
Mol Neurobiol ; 60(11): 6362-6372, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37450245

RESUMO

Autosomal dominant leukodystrophy (ADLD) is an ultra-rare, slowly progressive, and fatal neurodegenerative disorder associated with the loss of white matter in the central nervous system (CNS). Several years after its first clinical description, ADLD was found to be caused by coding and non-coding variants in the LMNB1 gene that cause its overexpression in at least the brain of patients. LMNB1 encodes for Lamin B1, a protein of the nuclear lamina. Lamin B1 regulates many cellular processes such as DNA replication, chromatin organization, and senescence. However, its functions have not been fully characterized yet. Nevertheless, Lamin B1 together with the other lamins that constitute the nuclear lamina has firstly the key role of maintaining the nuclear structure. Being the nucleus a dynamic system subject to both biochemical and mechanical regulation, it is conceivable that changes to its structural homeostasis might translate into functional alterations. Under this light, this review aims at describing the pieces of evidence that to date have been obtained regarding the effects of LMNB1 overexpression on cellular morphology and functionality. Moreover, we suggest that further investigation on ADLD morpho-functional consequences is essential to better understand this complex disease and, possibly, other neurological disorders affecting CNS myelination.


Assuntos
Doenças Desmielinizantes , Doenças por Armazenamento dos Lisossomos , Doenças Neurodegenerativas , Humanos , Doenças Raras , Doenças Desmielinizantes/metabolismo , Encéfalo/metabolismo , Modelos Teóricos
17.
Front Cell Neurosci ; 17: 1263310, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37720548

RESUMO

Lamin B1 is an essential protein of the nuclear lamina that plays a crucial role in nuclear function and organization. It has been demonstrated that lamin B1 is essential for organogenesis and particularly brain development. The important role of lamin B1 in physiological brain development and aging has only recently been at the epicenter of attention and is yet to be fully elucidated. Regarding the development of brain, glial cells that have long been considered as supporting cells to neurons have overturned this representation and current findings have displayed their active roles in neurogenesis and cerebral development. Although lamin B1 has increased levels during the differentiation of the brain cells, during aging these levels drop leading to senescent phenotypes and inciting neurodegenerative disorders such as Alzheimer's and Parkinson's disease. On the other hand, overexpression of lamin B1 leads to the adult-onset neurodegenerative disease known as Autosomal Dominant Leukodystrophy. This review aims at highlighting the importance of balancing lamin B1 levels in glial cells and neurons from brain development to aging.

18.
Clin Epigenetics ; 15(1): 27, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36803590

RESUMO

BACKGROUND: miRNAs are small non-coding RNAs that regulate gene expression and are linked to cancer development and progression. miRNA profiles are currently studied as new prognostic factors or therapeutic perspectives. Among hematological cancers, myelodysplastic syndromes at higher risk of evolution into acute myeloid leukemia are treated with hypomethylating agents, like azacitidine, alone or in combination with other drugs, such as lenalidomide. Recent data showed that, during azacitidine and lenalidomide therapy, the concurrent acquisition of specific point mutations affecting inositide signalling pathways is associated with lack or loss of response to therapy. As these molecules are implicated in epigenetic processes, possibly involving miRNA regulation, and in leukemic progression, through the regulation of proliferation, differentiation and apoptosis, here we performed a new miRNA expression analysis of 26 high-risk patients with myelodysplastic syndromes treated with azacitidine and lenalidomide at baseline and during therapy. miRNA array data were processed, and bioinformatic results were correlated with clinical outcome to investigate the translational relevance of selected miRNAs, while the relationship between selected miRNAs and specific molecules was experimentally tested and proven. RESULTS: Patients' overall response rate was 76.9% (20/26 cases): complete remission (5/26, 19.2%), partial remission (1/26, 3.8%), marrow complete remission (2/26, 7.7%), hematologic improvement (6/26, 23.1%), hematologic improvement with marrow complete remission (6/26, 23.1%), whereas 6/26 patients (23.1%) had a stable disease. miRNA paired analysis showed a statistically significant up-regulation of miR-192-5p after 4 cycles of therapy (vs baseline), that was confirmed by real-time PCR analyses, along with an involvement of BCL2, that was proven to be a miR-192-5p target in hematopoietic cells by luciferase assays. Furthermore, Kaplan-Meier analyses showed a significant correlation between high levels of miR-192-5p after 4 cycles of therapy and overall survival or leukemia-free survival, that was stronger in responders, as compared with patients early losing response and non-responders. CONCLUSIONS: This study shows that high levels of miR-192-5p are associated with higher overall survival and leukemia-free survival in myelodysplastic syndromes responding to azacitidine and lenalidomide. Moreover, miR-192-5p specifically targets and inhibits BCL2, possibly regulating proliferation and apoptosis and leading to the identification of new therapeutic targets.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Síndromes Mielodisplásicas , Humanos , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Lenalidomida/farmacologia , Lenalidomida/uso terapêutico , MicroRNAs/genética , Metilação de DNA , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogênicas c-bcl-2
19.
Proc Natl Acad Sci U S A ; 106(39): 16811-6, 2009 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-19805378

RESUMO

Lipid signaling pathways are involved in cell growth, differentiation, and apoptosis, and could have a role in the progression of myelodysplastic syndromes (MDS) into acute myeloid leukemia (AML). Indeed, recent studies showed that phosphoinositide-phospholipase (PI-PL)Cbeta1 mono-allelic deletion correlates with a higher risk of AML evolution. Also, a single patient treated with azacitidine, a DNA methyltransferase inhibitor currently used in MDS, displayed a direct correlation between PI-PLCbeta1 gene expression and drug responsiveness. Consequently, we hypothesized that PI-PLCbeta1 could be a target for demethylating therapy. First, we analyzed the structure of PI-PLCbeta1 gene promoter, then quantified the degree of PI-PLCbeta1 promoter methylation and gene expression in MDS patients at baseline and during azacitidine administration. Indeed, PI-PLCbeta1 mRNA increased in responder patients, along with a reduction of PI-PLCbeta1 promoter methylation. Also, the molecular response correlated to and anticipated the clinical outcome, thus suggesting that PI-PLCbeta1 gene reactivation could predict azacitidine responsiveness. Our results demonstrate not only that PI-PLCbeta1 promoter is hypermethylated in high-risk MDS patients, but also that the amount of PI-PLCbeta1 mRNA could predict the clinical response to azacitidine, therefore indicating a promising new therapeutic approach.


Assuntos
Azacitidina/farmacologia , Inibidores Enzimáticos/farmacologia , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/enzimologia , Fosfoinositídeo Fosfolipase C/metabolismo , Fosfolipase C beta/metabolismo , Idoso , Idoso de 80 Anos ou mais , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Pessoa de Meia-Idade , Fosfoinositídeo Fosfolipase C/genética , Fosfolipase C beta/genética , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo
20.
Biomolecules ; 12(3)2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35327539

RESUMO

Renal failure is a worldwide disease with a continuously increasing prevalence and involving a rising need for long-term treatment, mainly by haemodialysis. Arteriovenous fistula (AVF) is the favourite type of vascular access for haemodialysis; however, the lasting success of this therapy depends on its maturation, which is directly influenced by many concomitant processes such as vein wall thickening or inflammation. Understanding the molecular mechanisms that drive AVF maturation and failure can highlight new or combinatorial drugs for more personalized therapy. In this review we analysed the relevance of critical enzymes such as PI3K, AKT and mTOR in processes such as wall thickening remodelling, immune system activation and inflammation reduction. We focused on these enzymes due to their involvement in the modulation of numerous cellular activities such as proliferation, differentiation and motility, and their impairment is related to many diseases such as cancer, metabolic syndrome and neurodegenerative disorders. In addition, these enzymes are highly druggable targets, with several inhibitors already being used in patient treatment for cancer and with encouraging results for AVF. Finally, we delineate how these enzymes may be targeted to control specific aspects of AVF in an effort to propose a more specialized therapy with fewer side effects.


Assuntos
Fístula Arteriovenosa , Derivação Arteriovenosa Cirúrgica , Falência Renal Crônica , Fístula Arteriovenosa/etiologia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Feminino , Humanos , Inflamação/etiologia , Falência Renal Crônica/terapia , Masculino , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Serina-Treonina Quinases TOR
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