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1.
Cancer Metastasis Rev ; 42(4): 1155-1167, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37353690

RESUMO

Metastatic progression is regulated by metastasis promoter and suppressor genes. NME1, the prototypic and first described metastasis suppressor gene, encodes a nucleoside diphosphate kinase (NDPK) involved in nucleotide metabolism; two related family members, NME2 and NME4, are also reported as metastasis suppressors. These proteins physically interact with members of the GTPase dynamin family, which have key functions in membrane fission and fusion reactions necessary for endocytosis and mitochondrial dynamics. Evidence supports a model in which NDPKs provide GTP to dynamins to maintain a high local GTP concentration for optimal dynamin function. NME1 and NME2 are cytosolic enzymes that provide GTP to dynamins at the plasma membrane, which drive endocytosis, suggesting that these NMEs are necessary to attenuate signaling by receptors on the cell surface. Disruption of NDPK activity in NME-deficient tumors may thus drive metastasis by prolonging signaling. NME4 is a mitochondrial enzyme that interacts with the dynamin OPA1 at the mitochondria inner membrane to drive inner membrane fusion and maintain a fused mitochondrial network. This function is consistent with the current view that mitochondrial fusion inhibits the metastatic potential of tumor cells whereas mitochondrial fission promotes metastasis progression. The roles of NME family members in dynamin-mediated endocytosis and mitochondrial dynamics and the intimate link between these processes and metastasis provide a new framework to understand the metastasis suppressor functions of NME proteins.


Assuntos
Nucleosídeo NM23 Difosfato Quinases , Neoplasias , Humanos , Nucleosídeo NM23 Difosfato Quinases/genética , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Dinaminas/metabolismo , Neoplasias/patologia , Membrana Celular/metabolismo , Guanosina Trifosfato
2.
BMC Biol ; 19(1): 228, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34674701

RESUMO

BACKGROUND: Mitochondrial nucleoside diphosphate kinase (NDPK-D, NME4, NM23-H4) is a multifunctional enzyme mainly localized in the intermembrane space, bound to the inner membrane. RESULTS: We constructed loss-of-function mutants of NDPK-D, lacking either NDP kinase activity or membrane interaction and expressed mutants or wild-type protein in cancer cells. In a complementary approach, we performed depletion of NDPK-D by RNA interference. Both loss-of-function mutations and NDPK-D depletion promoted epithelial-mesenchymal transition and increased migratory and invasive potential. Immunocompromised mice developed more metastases when injected with cells expressing mutant NDPK-D as compared to wild-type. This metastatic reprogramming is a consequence of mitochondrial alterations, including fragmentation and loss of mitochondria, a metabolic switch from respiration to glycolysis, increased ROS generation, and further metabolic changes in mitochondria, all of which can trigger pro-metastatic protein expression and signaling cascades. In human cancer, NME4 expression is negatively associated with markers of epithelial-mesenchymal transition and tumor aggressiveness and a good prognosis factor for beneficial clinical outcome. CONCLUSIONS: These data demonstrate NME4 as a novel metastasis suppressor gene, the first localizing to mitochondria, pointing to a role of mitochondria in metastatic dissemination.


Assuntos
Neoplasias , Núcleosídeo-Difosfato Quinase , Animais , Membranas Intracelulares , Camundongos , Mitocôndrias , Nucleosídeo NM23 Difosfato Quinases/genética , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Nucleosídeo Difosfato Quinase D/metabolismo , Núcleosídeo-Difosfato Quinase/genética , Núcleosídeo-Difosfato Quinase/metabolismo
3.
Int J Mol Sci ; 22(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918324

RESUMO

Epithelial-mesenchymal transition (EMT) is important for the initial steps of metastasis. Although it is well accepted that the nucleoside diphosphate kinase NME1 is a metastasis suppressor, its effect on EMT remains poorly documented, as does that of its closely related isoform, NME2. Here, by using gene silencing, inactivation and overexpression strategies in a variety of cellular models of cancer, we show that NME1 is a powerful inhibitor of EMT. Genetic manipulation of NME2, by contrast, had no effect on the EMT phenotype of cancer cells, indicating a specific function of NME1 in EMT regulation. Loss of NME1 in epithelial cancer cells resulted in a hybrid phenotype intermediate between epithelial and mesenchymal cells, which is known to be associated with cells with a highly metastatic character. Conversely, overexpression of NME1 in mesenchymal cancer cells resulted in a more epithelial phenotype. We found that NME1 expression was negatively associated with EMT markers in many human cancers and was reduced in human breast tumor cell lines with the aggressive 'triple-negative' phenotype when compared to human breast tumor cell lines positive for estrogen receptor. We show that NME1, but not NME2, is an inhibitor of essential concerted intracellular signaling pathways involved in inducing EMT, including the AKT and MAPK (ERK, p38, and JNK) pathways. Additionally, NME1 depletion considerably altered the distribution of E-cadherin, a gatekeeper of the epithelial phenotype, shifting it from the plasma membrane to the cytosol and resulting in less E-cadherin on the cell surface than in control cells. Functional aggregation and dispersion assays demonstrated that inactivation of NME1 decreases E-cadherin-mediated cell-cell adhesion. We conclude that NME1, but not NME2, acts specifically to inhibit EMT and prevent the earliest stages of metastasis.


Assuntos
Transição Epitelial-Mesenquimal , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Animais , Caderinas/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Feminino , Edição de Genes , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos Nus , Neoplasias de Mama Triplo Negativas/metabolismo
4.
FASEB J ; 33(10): 11606-11614, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31242766

RESUMO

Phagocytosis of various targets, such as apoptotic cells or opsonized pathogens, by macrophages is coordinated by a complex signaling network initiated by distinct phagocytic receptors. Despite the different initial signaling pathways, each pathway ends up regulating the actin cytoskeletal network, phagosome formation and closure, and phagosome maturation leading to degradation of the engulfed particle. Herein, we describe a new phagocytic function for the nucleoside diphosphate kinase 1 (NDK-1), the nematode counterpart of the first identified metastasis inhibitor NM23-H1 (nonmetastatic clone number 23) nonmetastatic clone number 23 or nonmetastatic isoform 1 (NME1). We reveal by coimmunoprecipitation, Duolink proximity ligation assay, and mass spectrometry that NDK-1/NME1 works in a complex with DYN-1/Dynamin (Caenorhabditis elegans/human homolog proteins), which is essential for engulfment and phagosome maturation. Time-lapse microscopy shows that NDK-1 is expressed on phagosomal surfaces during cell corpse clearance in the same time window as DYN-1. Silencing of NM23-M1 in mouse bone marrow-derived macrophages resulted in decreased phagocytosis of apoptotic thymocytes. In human macrophages, NM23-H1 and Dynamin are corecruited at sites of phagosome formation in F-actin-rich cups. In addition, NM23-H1 was required for efficient phagocytosis. Together, our data demonstrate that NDK-1/NME1 is an evolutionarily conserved element of successful phagocytosis.-Farkas, Z., Petric, M., Liu, X., Herit, F., Rajnavölgyi, É., Szondy, Z., Budai, Z., Orbán, T. I., Sándor, S., Mehta, A., Bajtay, Z., Kovács, T., Jung, S. Y., Afaq Shakir, M., Qin, J., Zhou, Z., Niedergang, F., Boissan, M., Takács-Vellai, K. The nucleoside diphosphate kinase NDK-1/NME1 promotes phagocytosis in concert with DYN-1/dynamin.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Dinaminas/metabolismo , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Fagocitose/fisiologia , Actinas/metabolismo , Animais , Apoptose/fisiologia , Caenorhabditis elegans/metabolismo , Células Cultivadas , Humanos , Leucócitos Mononucleares/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fagossomos/metabolismo , Transdução de Sinais/fisiologia
5.
Cancer Metastasis Rev ; 42(4): 1069, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37936025
6.
BMC Infect Dis ; 19(1): 252, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30871501

RESUMO

BACKGROUND: During fulminant meningococcal septicaemia, meningococci are often observed in the cerebrospinal fluid (CSF) although the patients have frequently no meningeal symptoms. Meningococcal meningitis, by contrast, usually features clinical meningeal signs and biochemical markers of inflammation with elevated white blood cell count (pleiocytosis) in the CSF. Cases of typical symptomatic meningitis without these biochemical features are uncommon in adults. CASE PRESENTATION: A 21-year-old male presented with meningococcal purpura fulminans and disseminated intravascular coagulation (DIC) associated with multiple organ dysfunction syndrome requiring hospitalization in the Intensive Care Unit. Despite typical meningeal clinical signs, lumbar puncture showed no pleiocytosis, normal glycorachia and normal proteinorachia, whereas the lactate concentration in the CSF was high (5.8 mmol/L). CSF culture showed a high inoculum of serogroup C meningococci. On day 2, after initial improvement, a recurrence of hypotension led to the diagnosis of acute meningococcal myocarditis, which evolved favourably within a week. During the hospitalization, distal ischemic and necrotic lesions were observed, predominantly on the fingertips, which were treated with local and systemic vasodilators. CONCLUSIONS: We report a rare case of adult meningococcal disease characterized by an intermediate form of meningitis between purulent meningitis and meningeal inoculation from fulminant meningococcal septicaemia, without classical signs of biological inflammation. It highlights the diagnostic value of CSF lactate, which may warrant administration of a meningeal dosing regimen of beta-lactam antibiotics. This case also demonstrates the potential severity of meningococcal myocarditis; we discuss its pathophysiology, which is distinct from other sepsis-related cardiomyopathies. Finally, the observed effects of vasodilators on the meningococcal skin ischemia in this case encourages future studies to assess their efficacy in DIC-associated necrosis.


Assuntos
Meningite Meningocócica/diagnóstico , Miocardite/diagnóstico , Neisseria meningitidis Sorogrupo C/isolamento & purificação , Púrpura Fulminante/diagnóstico , Adulto , Humanos , Masculino , Meningite Meningocócica/microbiologia , Miocardite/microbiologia , Neisseria meningitidis Sorogrupo C/genética , Neisseria meningitidis Sorogrupo C/fisiologia , Púrpura Fulminante/microbiologia , Adulto Jovem
7.
Lab Invest ; 98(2): 164-174, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29451272

RESUMO

Nucleoside diphosphate kinases (NDPK) are nucleotide metabolism enzymes encoded by NME genes (also called NM23). Given the fact that not all NME-encoded proteins are catalytically active NDPKs and that NM23 generally refers to clinical studies on metastasis, we use here NME/NDPK to denote the proteins. Since their discovery in the 1950's, NMEs/NDPKs have been shown to be involved in multiple physiological and pathological cellular processes, but the molecular mechanisms have not been fully determined. Recent progress in elucidating these underlying mechanisms has been presented by experts in the field at the 10th International Congress on the NDPK/NME/AWD protein family in October 2016 in Dubrovnik, Croatia, and is summarized in review articles or original research in this and an upcoming issue of Laboratory Investigation. Within this editorial, we discuss three major cellular processes that involve members of the multi-functional NME/NDPK family: (i) cancer and metastasis dissemination, (ii) membrane remodeling and nucleotide channeling, and iii) protein histidine phosphorylation.


Assuntos
Família Multigênica , Núcleosídeo-Difosfato Quinase/genética , Animais , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Metástase Neoplásica/genética , Neoplasias/enzimologia , Neoplasias/genética , Neoplasias/patologia , Núcleosídeo-Difosfato Quinase/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
8.
Lab Invest ; 98(5): 582-588, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29491425

RESUMO

Mitochondrial nucleoside diphosphate kinase (NDPK-D; synonyms: NME4, NM23-H4) represents the major mitochondrial NDP kinase. The homohexameric complex emerged as a protein with multiple functions in bioenergetics and phospholipid signaling. It occurs at different but precise mitochondrial locations and can affect among other mitochondrial shapes and dynamics, as well as the specific elimination of defective mitochondria or cells via mitophagy or apoptosis. With these various functions in cell homeostasis, NDPK-D/NME4 adds to the group of so-called moonlighting (or gene sharing) proteins.


Assuntos
Homeostase , Nucleosídeo Difosfato Quinase D/fisiologia , Animais , Apoptose , Humanos , Mitofagia , Neoplasias/patologia , Nucleosídeo Difosfato Quinase D/análise , Nucleosídeo Difosfato Quinase D/química , Nucleosídeo Difosfato Quinase D/genética , Fosfolipídeos/química
9.
Lab Invest ; 98(6): 696-707, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29491426

RESUMO

Breast cancer is a major health problem worldwide. In ~15% of breast cancers, the epidermal growth factor receptor HER2, a transmembrane protein, is overexpressed. This HER2 overexpression is associated with an aggressive form of the disease and a poor clinical prognosis. The extracellular domain (ECD) of HER2 is released into the blood by a proteolytic mechanism known as "ECD shedding". This proteolytic shedding leaves a constitutively active truncated receptor in the membrane that is 10-100-fold more oncogenic than the full-length receptor and promotes the growth and survival of cancer cells. Shedding of the HER2 ECD is increased during metastasis: whereas 15% of primary breast cancer patients have elevated levels of serum HER2 ECD (sHER2 ECD), the levels reach 45% in patients with metastatic disease. Thus, sHER2 ECD has been proposed as a promising biomarker for cancer recurrence and for monitoring the disease status of patients overexpressing HER2. Nevertheless, in 2016, the American Society of Clinical Oncology advises clinicians not to use soluble HER2 levels to guide their choice of adjuvant therapy for patients with HER2-positive breast cancer, because the evidence was considered not strong enough. Currently, biomarkers such as carcinoembryonic antigen and cancer antigen 15-3 are widely used to monitor metastatic breast cancer disease even if the level of evidence of clinical impact of this monitoring is poor. In this article, we review the evidence that sHER2 ECD might be used in some situations as a biomarker for breast cancer. Although this serum biomarker will not replace the direct measurement of tumor HER2 status for diagnosis of early-stage tumors; it might be especially useful in metastatic disease for prognosis, as an indicator of cancer progression and of therapy response, particularly to anti-HER2 therapies. Owing to these data, sHER2 ECD should be considered as a promising biomarker to detect cancer recurrence and metastasis.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Receptor ErbB-2/sangue , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Metástase Neoplásica , Recidiva Local de Neoplasia , Prognóstico , Domínios Proteicos , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/química
10.
Lab Invest ; 98(2): 228-232, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29035377

RESUMO

Mitophagy is an emerging paradigm for mitochondrial quality control and cell homeostasis. Dysregulation of mitophagy can lead to human pathologies such as neurodegenerative disorders and contributes to the aging process. Complex protein signaling cascades have been described that regulate mitophagy. We have identified a novel lipid signaling pathway that involves the phospholipid cardiolipin (CL). CL is synthesized and normally confined at the inner mitochondrial membrane. However, upon a mitophagic trigger, ie, collapse of the inner membrane potential, CL is rapidly externalized to the mitochondrial surface with the assistance of the hexameric nucleoside diphosphate kinase D (NME4, NDPK-D, or NM23-H4). In addition to its NDP kinase activity, NME4/NDPK-D shows intermembrane phospholipid transfer activity in vitro and in cellular systems, which relies on NME4/NDPK-D interaction with CL, CL-dependent crosslinking of inner and outer mitochondrial membranes by symmetrical, hexameric NME4/NDPK-D, and a putative NME4/NDPK-D-based CL-transfer pathway. CL exposed at the mitochondrial surface then serves as an 'eat me' signal for the mitophagic machinery; it is recognized by the LC3 receptor of autophagosomes, targeting the dysfunctional mitochondrion to lysosomal degradation. Similar NME4-supported CL externalization is likely also involved in apoptosis and inflammatory reactions.


Assuntos
Cardiolipinas/metabolismo , Mitofagia , Nucleosídeo Difosfato Quinase D/metabolismo , Transdução de Sinais , Animais , Apoptose , Humanos , Membranas Mitocondriais/metabolismo , Modelos Biológicos , Ligação Proteica
11.
FASEB J ; 31(4): 1531-1546, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28077425

RESUMO

NME1 (nonmetastatic expressed 1) gene, which encodes nucleoside diphosphate kinase (NDPK) A [also known as nonmetastatic clone 23 (NM23)-H1 in humans and NM23-M1 in mice], is a suppressor of metastasis, but several lines of evidence-mostly from plants-also implicate it in the regulation of the oxidative stress response. Here, our aim was to investigate the physiologic relevance of NDPK A with respect to the oxidative stress response in mammals and to study its molecular basis. NME1-knockout mice died sooner, suffered greater hepatocyte injury, and had lower superoxide dismutase activity than did wild-type (WT) mice in response to paraquat-induced acute oxidative stress. Deletion of NME1 reduced total NDPK activity and exacerbated activation of the stress-related MAPK, JNK, in the liver in response to paraquat. In a mouse transformed hepatocyte cell line and in primary cultures of normal human keratinocytes, MAPK activation in response to H2O2 and UVB, respectively, was dampened by expression of NM23-M1/NM23-H1, dependent on its NDPK catalytic activity. Furthermore, excess or depletion of NM23-M1/NM23-H1 NDPK activity did not affect the intracellular bulk concentration of nucleoside di- and triphosphates. NME1-deficient mouse embryo fibroblasts grew poorly in culture, were more sensitive to stress than WT fibroblasts, and did not immortalize, which suggested that they senesce earlier than do WT fibroblasts. Collectively, these results indicate that the NDPK activity of NM23-M1/NM23-H1 protects cells from acute oxidative stress by inhibiting activation of JNK in mammal models.-Peuchant, E., Bats, M.-L., Moranvillier, I., Lepoivre, M., Guitton, J., Wendum, D., Lacombe, M.-L., Moreau-Gaudry, F., Boissan, M., Dabernat, S. Metastasis suppressor NM23 limits oxidative stress in mammals by preventing activation of stress-activated protein kinases/JNKs through its nucleoside diphosphate kinase activity.


Assuntos
Sistema de Sinalização das MAP Quinases , Nucleosídeo NM23 Difosfato Quinases/genética , Estresse Oxidativo , Animais , Linhagem Celular , Células Cultivadas , Fibroblastos/metabolismo , Deleção de Genes , Hepatócitos/metabolismo , Humanos , Queratinócitos/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Paraquat/toxicidade
12.
J Biol Chem ; 288(1): 111-21, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23150663

RESUMO

The nucleoside diphosphate kinase Nm23-H4/NDPK-D forms symmetrical hexameric complexes in the mitochondrial intermembrane space with phosphotransfer activity using mitochondrial ATP to regenerate nucleoside triphosphates. We demonstrate the complex formation between Nm23-H4 and mitochondrial GTPase OPA1 in rat liver, suggesting its involvement in local and direct GTP delivery. Similar to OPA1, Nm23-H4 is further known to strongly bind in vitro to anionic phospholipids, mainly cardiolipin, and in vivo to the inner mitochondrial membrane. We show here that such protein-lipid complexes inhibit nucleoside diphosphate kinase activity but are necessary for another function of Nm23-H4, selective intermembrane lipid transfer. Mitochondrial lipid distribution was analyzed by liquid chromatography-mass spectrometry using HeLa cells expressing either wild-type Nm23-H4 or a membrane binding-deficient mutant at a site predicted based on molecular modeling to be crucial for cardiolipin binding and transfer mechanism. We found that wild type, but not the mutant enzyme, selectively increased the content of cardiolipin in the outer mitochondrial membrane, but the distribution of other more abundant phospholipids (e.g. phosphatidylcholine) remained unchanged. HeLa cells expressing the wild-type enzyme showed increased accumulation of Bax in mitochondria and were sensitized to rotenone-induced apoptosis as revealed by stimulated release of cytochrome c into the cytosol, elevated caspase 3/7 activity, and increased annexin V binding. Based on these data and molecular modeling, we propose that Nm23-H4 acts as a lipid-dependent mitochondrial switch with dual function in phosphotransfer serving local GTP supply and cardiolipin transfer for apoptotic signaling and putative other functions.


Assuntos
Cardiolipinas/fisiologia , Membranas Intracelulares/metabolismo , Lipídeos/química , Nucleosídeo Difosfato Quinase D/química , Nucleosídeo Difosfato Quinase D/fisiologia , Animais , Apoptose , Cardiolipinas/química , GTP Fosfo-Hidrolases/química , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Modelos Moleculares , Fosfolipídeos/química , Ligação Proteica , Conformação Proteica , Ratos , Ratos Wistar
13.
Hepatology ; 58(4): 1401-12, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23696511

RESUMO

UNLABELLED: Alterations in apical junctional complexes (AJCs) have been reported in genetic or acquired biliary diseases. The vitamin D nuclear receptor (VDR), predominantly expressed in biliary epithelial cells in the liver, has been shown to regulate AJCs. The aim of our study was thus to investigate the role of VDR in the maintenance of bile duct integrity in mice challenged with biliary-type liver injury. Vdr(-/-) mice subjected to bile duct ligation (BDL) displayed increased liver damage compared to wildtype BDL mice. Adaptation to cholestasis, ascertained by expression of genes involved in bile acid metabolism and tissue repair, was limited in Vdr(-/-) BDL mice. Furthermore, evaluation of Vdr(-/-) BDL mouse liver tissue sections indicated altered E-cadherin staining associated with increased bile duct rupture. Total liver protein analysis revealed that a truncated form of E-cadherin was present in higher amounts in Vdr(-/-) mice subjected to BDL compared to wildtype BDL mice. Truncated E-cadherin was also associated with loss of cell adhesion in biliary epithelial cells silenced for VDR. In these cells, E-cadherin cleavage occurred together with calpain 1 activation and was prevented by the silencing of calpain 1. Furthermore, VDR deficiency led to the activation of the epidermal growth factor receptor (EGFR) pathway, while EGFR activation by EGF induced both calpain 1 activation and E-cadherin cleavage in these cells. Finally, truncation of E-cadherin was blunted when EGFR signaling was inhibited in VDR-silenced cells. CONCLUSION: Biliary-type liver injury is exacerbated in Vdr(-/-) mice by limited adaptive response and increased bile duct rupture. These results indicate that loss of VDR restricts the adaptation to cholestasis and diminishes bile duct integrity in the setting of biliary-type liver injury.


Assuntos
Sistema Biliar/patologia , Colestase/fisiopatologia , Células Epiteliais/patologia , Junções Intercelulares/patologia , Fígado/fisiopatologia , Receptores de Calcitriol/deficiência , Sequência de Aminoácidos , Animais , Ductos Biliares/fisiopatologia , Caderinas/análise , Caderinas/fisiologia , Calpaína/fisiologia , Colestase/patologia , Modelos Animais de Doenças , Receptores ErbB/fisiologia , Ligadura , Fígado/patologia , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Receptores de Calcitriol/fisiologia
14.
Am J Pathol ; 180(1): 131-40, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22056911

RESUMO

Mitotic kinesin-like protein 2 (MKlp2), a microtubule-associated motor, is required during mitosis exit for the final step of cytokinesis. It also contributes to retrograde vesicular trafficking from the Golgi apparatus to the endoplasmic reticulum in interphase. The KIF20A gene encoding MKlp2 is controlled by the E2F-retinoblastoma protein-p16 pathway, and its widely expressed mRNA is found in fetal and proliferating adult tissues. The expression pattern and function of MKlp2 in the adult liver, however, have not been investigated. We report herein that MKlp2 transiently accumulates in vivo during mouse liver regeneration after partial hepatectomy and is strongly overexpressed in preneoplastic and neoplastic mouse liver. In vitro in mitogen-stimulated primary hepatocytes, MKlp2 accumulated in the nucleus during the G2 phase of the cell cycle coincident with the mitotic kinase Aurora B. Human hepatoma cell lines exhibited high levels of MKlp2; however, it was undetectable in normal human hepatocytes. RNAi-mediated MKlp2 knockdown in hepatoma cells induced polyploidization consistent with its essential function in promoting cytokinesis and inhibited cell proliferation without inducing apoptosis. KIF20A mRNA was strongly accumulated in a large series of human hepatocellular carcinomas, with the highest expression observed in tumors with genomic instability. Accumulation of MKlp2 in normal proliferating, preneoplastic, and transformed hepatocytes suggests that MKlp2 contributes to both normal and pathologic hepatocyte proliferation and is linked to tumor aggressiveness in human hepatocellular carcinomas.


Assuntos
Carcinoma Hepatocelular/metabolismo , Transformação Celular Neoplásica/metabolismo , Cinesinas/metabolismo , Neoplasias Hepáticas/metabolismo , Regeneração Hepática/fisiologia , Lesões Pré-Cancerosas/metabolismo , Idoso , Animais , Carcinoma Hepatocelular/patologia , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Feminino , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Antígeno Ki-67/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Mitógenos/farmacologia , Lesões Pré-Cancerosas/patologia , Células Tumorais Cultivadas
15.
Ann Biol Clin (Paris) ; 81(1): 7-23, 2023 03 15.
Artigo em Francês | MEDLINE | ID: mdl-36757372

RESUMO

Prostate-specific antigen (PSA) is the recommended tumor marker for individual screening and follow-up of prostate cancer. This paper reviews main structural and physiological data about prostate specific antigen isoforms: total PSA, free PSA, [-2]proPSA (also named p2PSA). It describes the pre-, per- and post-analytical conditions for these different parameters. It presents the interpretation of results and derived calculated indices (free/total PSA ratio, Prostate Health Index or PHI) for the management of prostate cancer (initial diagnosis and follow-up).


Assuntos
Biomarcadores Tumorais , Antígeno Prostático Específico , Masculino , Humanos , Precursores de Proteínas , Isoformas de Proteínas , Neoplasias da Próstata/diagnóstico
16.
J Cell Biol ; 222(1)2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36250940

RESUMO

Integrin endocytosis is essential for many fundamental cellular processes. Whether and how the internalization impacts cellular mechanics remains elusive. Whereas previous studies reported the contribution of the integrin activator, talin, in force development, the involvement of inhibitors is less documented. We identified ICAP-1 as an integrin inhibitor involved in mechanotransduction by co-working with NME2 to control clathrin-mediated endocytosis of integrins at the edge of focal adhesions (FA). Loss of ICAP-1 enables ß3-integrin-mediated force generation independently of ß1 integrin. ß3-integrin-mediated forces were associated with a decrease in ß3 integrin dynamics stemming from their reduced diffusion within adhesion sites and slow turnover of FA. The decrease in ß3 integrin dynamics correlated with a defect in integrin endocytosis. ICAP-1 acts as an adaptor for clathrin-dependent endocytosis of integrins. ICAP-1 controls integrin endocytosis by interacting with NME2, a key regulator of dynamin-dependent clathrin-coated pits fission. Control of clathrin-mediated integrin endocytosis by an inhibitor is an unprecedented mechanism to tune forces at FA.


Assuntos
Clatrina , Endocitose , Adesões Focais , Integrina beta1 , Integrina beta3 , Clatrina/metabolismo , Endocitose/fisiologia , Integrina beta1/genética , Mecanotransdução Celular , Talina/genética
17.
J Exp Clin Cancer Res ; 42(1): 318, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38008756

RESUMO

BACKGROUND: TGFß induces several cell phenotypes including senescence, a stable cell cycle arrest accompanied by a secretory program, and epithelial-mesenchymal transition (EMT) in normal epithelial cells. During carcinogenesis cells lose the ability to undergo senescence in response to TGFß but they maintain an EMT, which can contribute to tumor progression. Our aim was to identify mechanisms promoting TGFß-induced senescence escape. METHODS: In vitro experiments were performed with primary human mammary epithelial cells (HMEC) immortalized by hTert. For kinase library screen and modulation of gene expression retroviral transduction was used. To characterize gene expression, RNA microarray with GSEA analysis and RT-qPCR were used. For protein level and localization, Western blot and immunofluorescence were performed. For senescence characterization crystal violet assay, Senescence Associated-ß-Galactosidase activity, EdU staining were conducted. To determine RSK3 partners FLAG-baited immunoprecipitation and mass spectrometry-based proteomic analyses were performed. Proteosome activity and proteasome enrichment assays were performed. To validate the role of RSK3 in human breast cancer, analysis of METABRIC database was performed. Murine intraductal xenografts using MCF10DCIS.com cells were carried out, with histological and immunofluorescence analysis of mouse tissue sections. RESULTS: A screen with active kinases in HMECs upon TGFß treatment identified that the serine threonine kinase RSK3, or RPS6KA2, a kinase mainly known to regulate cancer cell death including in breast cancer, reverted TGFß-induced senescence. Interestingly, RSK3 expression decreased in response to TGFß in a SMAD3-dependent manner, and its constitutive expression rescued SMAD3-induced senescence, indicating that a decrease in RSK3 itself contributes to TGFß-induced senescence. Using transcriptomic analyses and affinity purification coupled to mass spectrometry-based proteomics, we unveiled that RSK3 regulates senescence by inhibiting the NF-κΒ pathway through the decrease in proteasome-mediated IκBα degradation. Strikingly, senescent TGFß-treated HMECs display features of epithelial to mesenchymal transition (EMT) and during RSK3-induced senescence escaped HMECs conserve EMT features. Importantly, RSK3 expression is correlated with EMT and invasion, and inversely correlated with senescence and NF-κΒ in human claudin-low breast tumors and its expression enhances the formation of breast invasive tumors in the mouse mammary gland. CONCLUSIONS: We conclude that RSK3 switches cell fate from senescence to malignancy in response to TGFß signaling.


Assuntos
Neoplasias da Mama , Neoplasias Mamárias Animais , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteômica , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
18.
Bull Cancer ; 109(2): 170-184, 2022 Feb.
Artigo em Francês | MEDLINE | ID: mdl-35034786

RESUMO

Technological advances, in particular the development of high-throughput sequencing, have led to the emergence of a new generation of molecular biomarkers for tumors. These new tools have profoundly changed therapeutic management in oncology, with increasingly precise molecular characterization of tumors leading to increasingly personalized therapeutic targeting. Detection of circulating tumor cells and/or circulating tumor DNA in blood samples -so-called 'liquid biopsies'- can now provide a genetic snapshot of the patient's tumor through an alternative and less invasive procedure than biopsy of the tumor tissue itself. This procedure for characterizing and monitoring the disease in real time facilitates the search for possible relapses, the emergence of resistance, or emergence of a new therapeutic target. In the long term, it might also provide a means of early detection of cancer. These new approaches require the treatment of ever-increasing amounts of clinical data, notably, with the goal of calculating composite clinical-biological predictive scores. The use of artificial intelligence will be unavoidable in this domain, but it raises ethical questions and implications for the health-care system that will have to be addressed.


Assuntos
Inteligência Artificial/tendências , Biomarcadores Tumorais/sangue , Biópsia Líquida , Oncologia/tendências , Neoplasias/sangue , Medicina de Precisão/tendências , Inteligência Artificial/ética , DNA Tumoral Circulante/sangue , Gerenciamento de Dados , Detecção Precoce de Câncer/métodos , Sequenciamento de Nucleotídeos em Larga Escala/tendências , Humanos , Imunoterapia , Biópsia Líquida/métodos , Oncologia/métodos , MicroRNAs/sangue , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/diagnóstico , Neoplasias/genética , Neoplasias/terapia , Células Neoplásicas Circulantes
19.
Bull Cancer ; 109(2): 151-169, 2022 Feb.
Artigo em Francês | MEDLINE | ID: mdl-35012767

RESUMO

In oncology, the identification of targets that correlate with a type of cancer has led to a profound change in the notion of "tumor markers". Technological advances, in particular the development of high-throughput sequencing, have led to the emergence of a new generation of molecular biomarkers for tumors. Despite their limited utility for screening and diagnosis, conventional tumor markers remain interesting for evaluation of prognoses, the choice and optimization of treatments, as well as for monitoring the effectiveness of those treatments. In this article, we revisit the conventional serum markers that are enjoying a 'come back' thanks to the development of high-performance scores based on biological, cytological, clinical, or radiological criteria.


Assuntos
Biomarcadores Tumorais/sangue , Oncologia/métodos , Proteínas de Neoplasias/sangue , Neoplasias/sangue , Medicina de Precisão/métodos , França , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/diagnóstico , Neoplasias/diagnóstico , Neoplasias/imunologia , Neoplasias/terapia , Especificidade de Órgãos , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Resultado do Tratamento
20.
Front Cardiovasc Med ; 9: 931054, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935637

RESUMO

Background: Takotsubo syndrome is an acute cardiac condition usually involving abnormal regional left ventricular wall motion and impaired left ventricular contractility. It is due mainly to hyper-stimulation of the sympathetic nerve system, inducing an excess of catecholamines, usually triggered by intense psychological or physiological stress. The relationship between Takotsubo syndrome and the circulating stress hormones cortisol and copeptin (a surrogate marker of arginine vasopressin) has not been well documented. Case summary: Here, we describe the dynamic changes in circulating cortisol and copeptin during an entire episode of Takotsubo syndrome in a post-partum woman after spontaneous vaginal delivery. The patient was diagnosed with inverted Takotsubo syndrome accompanied by HELLP syndrome. We found qualitative and quantitative changes in cortisol: a loss of circadian rhythm and a three-fold elevation in the plasma concentration of the hormone with a peak appearing several hours before circulating cardiac biomarkers began to rise. By contrast, levels of copeptin remained normal during the entire episode. Discussion: Our findings indicate that the levels of cortisol change during Takotsubo syndrome whereas those of copeptin do not. This association between elevated cortisol and Takotsubo syndrome suggests that aberrant levels of this stress hormone may contribute to the observed cardiac pathology. We conclude that biochemical assays of circulating cortisol and cardiac biomarkers may be a useful complement to the diagnosis of Takotsubo syndrome by non-invasive cardiac imaging.

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