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1.
Cell Mol Biol Lett ; 29(1): 101, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978018

RESUMO

BACKGROUND: Prostate cancer (PCa) ranks as the second most prevalent cancer in men, with advanced stages posing significant treatment challenges. Given its solid tumor nature, PCa is highly susceptible to hypoxia, a condition associated with resistance to radiation and chemotherapy, metastasis, and unfavorable patient outcomes. Hypoxia-inducible factors (HIFs) play a pivotal role in cancer cell adaptation to hypoxic environments, contributing to treatment resistance. Consequently, inhibitors targeting HIFs hold promise for cancer therapy. METHODS: In this study, we aimed to characterize novel HIF-1α inhibitors including Sodwanones A (1), B (2), C (3), G (4) and Yardenone 2 (5) isolated from marine sponges belonging to the Axinella genus. Our investigation evaluated the impact of these compounds on various aspects of HIF-1α regulation, including stabilization, nuclear localization, expression of HIF-1 target genes (while sparing HIF-2 target genes), cellular metabolism, as well as cell proliferation and viability in prostate cells under hypoxic conditions. RESULTS: Our findings revealed that among the compounds tested, Yardenone 2 exhibited notable effects in hypoxia: it destabilized HIF-1α at the protein level, decreased its nuclear localization, selectively altered the expression of HIF-1 target genes, and restrained cell proliferation in aggressive PC3 prostate cancer cells as well as in an MSK-PCa3 patient-derived organoid line. Moreover, it affected the morphology of these organoid. Yardenone 2 was also compared to Docetaxel, a specific microtubule inhibitor and a drug used in the treatment of prostate cancer. The comparison between the two compounds revealed notable differences, such as a lack of specificity to hypoxic cells of Docetaxel. CONCLUSION: These results mark the first demonstration that Yardenone 2 functions as a cytostatic-like inhibitor impacting microtubules, specifically targeting hypoxic cancer cells. This discovery suggests a promising avenue for novel therapeutic interventions in prostate cancer.


Assuntos
Proliferação de Células , Subunidade alfa do Fator 1 Induzível por Hipóxia , Neoplasias da Próstata , Humanos , Masculino , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Animais , Poríferos/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Antineoplásicos/farmacologia , Hipóxia Celular/efeitos dos fármacos
2.
EMBO J ; 43(11): 2087-2090, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38698216
3.
J Physiol ; 599(8): 2299-2321, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33608879

RESUMO

KEY POINTS: Patients with end-stage renal failure need arteriovenous fistulas (AVF) to undergo dialysis. However, AVFs present a high rate of failure as a result of excessive venous thickness. Excessive venous thickness may be a consequence of surgical dissection and change in oxygen concentration within the venous wall. We show that venous cells adapt their metabolism and growth depending on oxygen concentration, and drugs targeting the hypoxic response pathway modulate this response in vitro. We used the same drugs on a mouse model of AVF and show that direct or indirect inhibition of the hypoxia-inducible factors (HIFs) help decrease excessive venous thickness. Hypoxia and HIFs can be targets of therapeutic drugs to prevent excessive venous thickness in patients undergoing AVF surgical creation. ABSTRACT: Because the oxygen concentration changes in the venous wall, surrounding tissue and the blood during surgical creation of arteriovenous fistula (AVF), we hypothesized that hypoxia could contribute to AVF failure as a result of neointimal hyperplasia. We postulated that modulation of the hypoxia-inducible factors (HIF) with pharmacological compounds could promote AVF maturation. Fibroblasts [normal human fibroblasts (NHF)], smooth muscle cells [human umbilical vein smooth muscle cells (HUVSMC)] and endothelial cells [human umbilical vein endothelial cells (HUVEC)], representing the three layers of the venous wall, were tested in vitro for proliferation, cell death, metabolism, reactive oxygen species production and migration after silencing of HIF1/2-α or after treatment with deferioxamine (DFO), everolimus (Eve), metformin (Met), N-acetyl-l-cysteine (NAC) and topoisomerase I (TOPO), which modulate HIF-α stability or activity. Compounds that were considered to most probably modify intimal hyperplasia were applied locally to the vessels in a mouse model of aortocaval fistula. We showed, in vitro, that NHF and HUVSMC can adapt their metabolism and thus their growth depending on oxygen concentration, whereas HUVEC appears to be less flexible. siHIF1/2α, DFO, Eve, Met, NAC and TOPO can modulate metabolism and proliferation depending on the cell type and the oxygen concentration. In vivo, siHIF1/2α, Eve and TOPO decreased neointimal hyperplasia by 32%-50%, 7 days after treatment. Within the vascular wall, hypoxia and HIF-1/2 mediate early failure of AVF. Local delivery of drugs targeting HIF-1/2 could inhibit neointimal hyperplasia in a mouse model of AVF. Such compounds may be delivered during the surgical procedure for AVF creation to prevent early AVF failure.


Assuntos
Fístula Arteriovenosa , Derivação Arteriovenosa Cirúrgica , Células Endoteliais , Humanos , Hiperplasia , Hipóxia
4.
J Cell Mol Med ; 24(5): 2931-2941, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32032472

RESUMO

Arteriovenous fistulas (AVFs) are the preferred vascular access for haemodialysis of patients suffering from end-stage renal disease, a worldwide public health problem. However, they are prone to a high rate of failure due to neointimal hyperplasia and stenosis. This study aimed to determine if osteopontin (OPN) was induced in hypoxia and if OPN could be responsible for driving AVF failure. Identification of new factors that participate in remodelling of AVFs is a challenge. Three cell lines representing the cells of the three layers of the walls of arteries and veins, fibroblasts, smooth muscle cells and endothelial cells, were tested in mono- and co-culture in vitro for OPN expression and secretion in normoxia compared to hypoxia after silencing the hypoxia-inducible factors (HIF-1α, HIF-2α and HIF-1/2α) with siRNA or after treatment with an inhibitor of NF-kB. None of the cells in mono-culture showed OPN induction in hypoxia, whereas cells in co-culture secreted OPN in hypoxia. The changes in oxygenation that occur during AVF maturation up-regulate secretion of OPN through cell-cell interactions between the different cell layers that form AVF, and in turn, these promote endothelial cell proliferation and could participate in neointimal hyperplasia.


Assuntos
Fibroblastos/citologia , Células Endoteliais da Veia Umbilical Humana/citologia , Miócitos de Músculo Liso/citologia , Osteopontina/metabolismo , Hipóxia Celular/genética , Técnicas de Cocultura , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Miócitos de Músculo Liso/metabolismo , Osteopontina/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
5.
J Cell Physiol ; 235(2): 1184-1196, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31294462

RESUMO

Brown and brown-like adipocytes (BBAs) control thermogenesis and are detected in adult humans. They express UCP1, which transforms energy into heat. They appear as promising cells to fight obesity. Deciphering the molecular mechanisms leading to the browning of human white adipocytes or the whitening of BBAs represents a goal to properly and safely control the pathways involved in these processes. Here, we analyzed how drugs endowed with therapeutic potential affect the differentiation of human adipose progenitor-cells into BBAs and/or their phenotype. We showed that HIV-protease inhibitors (PI) reduced UCP1 expression in BBAs modifying their metabolic profile and the mitochondria functionality. Lopinavir (LPV) was more potent than darunavir (DRV), a last PI generation. PPARγ and PGC-1α were decreased in a PI or cell-specific manner, thus altering UCP1's constitutive expression. In addition, LPV altered p38 MAPK phosphorylation, blunting then the ß-adrenergic responses. In contrast, low doses of resveratrol stimulated the activatable expression of UCP1 in a p38 MAPK-dependent manner and counteracted the LPV induced loss of UCP1. This effect was independent of the resveratrol-induced sirtuin-1 expression. Altogether our results uncover how drugs impact crucial components of the networks regulating the expression of the thermogenic signature. They provide important information to control the relevant pathways involved in energy expenditure.


Assuntos
Adipócitos/efeitos dos fármacos , Darunavir/farmacologia , Resveratrol/farmacologia , Proteína Desacopladora 1/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Adipócitos/metabolismo , Antioxidantes/farmacologia , Linhagem Celular , Colforsina , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores da Protease de HIV/farmacologia , Humanos , Compostos Orgânicos/farmacologia , Fosforilação , Proteína Desacopladora 1/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética
6.
Cell Mol Biol Lett ; 24: 18, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30949212

RESUMO

BACKGROUND: Polysaccharides from various sources have been used in traditional medicine for centuries. The beneficial pharmacological effects of plant-derived polysaccharides include anti-tumor activity. METHODS: Here, we evaluated the anti-cancer effect of the MSAGM:VO complex under hypoxic conditions (1% oxygen). MSAGM:VO is a complex of the hydrolysate of galactomannan (MSAGM) from Schizolobium amazonicum with oxovanadium (IV/V). The hepatocellular carcinoma (HCC) cell line HepG2 was selected as HCC are one of the most hypoxic solid tumors. RESULTS: Our results showed that the strong apoptotic activity of MSAGM:VO observed in HepG2 cells under normoxic conditions was completely lost under hypoxic conditions. We found a dynamic balance between the pro- and anti-apoptotic members of the Bcl-2 protein family. The expressions of anti-apoptotic Mcl-1 and Bcl-XL increased in hypoxia, whereas the expression of pro-apoptotic Bax decreased. MSAGM:VO strongly induced autophagy, which was previously characterized as a pro-survival mechanism in hypoxia. These results demonstrate total elimination of the anti-cancer activity of MSAGM:VO with activation of autophagy under conditions of hypoxia. CONCLUSION: Although this study is a proof-of-concept of the impact of hypoxia on the potential of polysaccharides, further study is encouraged. The anti-tumor activity of polysaccharides could be achieved in normoxia or through raising the activity of the immune system. In addition, combination strategies for therapy with anti-autophagic drugs could be proposed.


Assuntos
Citoproteção/efeitos dos fármacos , Mananas/farmacologia , Vanadatos/farmacologia , Morte Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Galactose/análogos & derivados , Células Hep G2 , Humanos
7.
Int J Mol Sci ; 20(6)2019 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-30884815

RESUMO

The primary cilium is a solitary, nonmotile and transitory appendage that is present in virtually all mammalian cells. Our knowledge of its ultrastructure and function is the result of more than fifty years of research that has dramatically changed our perspectives on the primary cilium. The mutual regulation between ciliogenesis and the cell cycle is now well-recognized, as well as the function of the primary cilium as a cellular "antenna" for perceiving external stimuli, such as light, odorants, and fluids. By displaying receptors and signaling molecules, the primary cilium is also a key coordinator of signaling pathways that converts extracellular cues into cellular responses. Given its critical tasks, any defects in primary cilium formation or function lead to a wide spectrum of diseases collectively called "ciliopathies". An emerging role of primary cilium is in the regulation of cancer development. In this review, we seek to describe the current knowledge about the influence of the primary cilium in cancer progression, with a focus on some of the events that cancers need to face to sustain survival and growth in hypoxic microenvironment: the cancer hallmarks.


Assuntos
Autofagia/genética , Biomarcadores Tumorais/genética , Cílios/ultraestrutura , Neoplasias/ultraestrutura , Ciclo Celular , Cílios/genética , Humanos , Neoplasias/genética , Neoplasias/patologia , Ligação Proteica/genética , Transdução de Sinais/genética , Microambiente Tumoral/genética
8.
Int J Mol Sci ; 20(21)2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671790

RESUMO

For patients with end-stage renal disease requiring hemodialysis, their vascular access is both their lifeline and their Achilles heel. Despite being recommended as primary vascular access, the arteriovenous fistula (AVF) shows sub-optimal results, with about 50% of patients needing a revision during the year following creation. After the AVF is created, the venous wall must adapt to new environment. While hemodynamic changes are responsible for the adaptation of the extracellular matrix and activation of the endothelium, surgical dissection and mobilization of the vein disrupt the vasa vasorum, causing wall ischemia and oxidative stress. As a consequence, migration and proliferation of vascular cells participate in venous wall thickening by a mechanism of neointimal hyperplasia (NH). When aggressive, NH causes stenosis and AVF dysfunction. In this review we show how hypoxia, metabolism, and flow parameters are intricate mechanisms responsible for the development of NH and stenosis during AVF maturation.


Assuntos
Fístula Arteriovenosa/metabolismo , Hiperplasia/metabolismo , Hipóxia/metabolismo , Neointima/metabolismo , Proliferação de Células , Constrição Patológica , Hemodinâmica , Humanos , Isquemia , Nefropatias , Diálise Renal , Insuficiência Renal Crônica , Doenças Vasculares , Veias/patologia
9.
FASEB J ; 30(2): 909-22, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26527067

RESUMO

Brown adipose tissue (BAT) is essential for adaptive thermogenesis and dissipation of caloric excess through the activity of uncoupling protein (UCP)-1. BAT in humans is of great interest for the treatment of obesity and related diseases. In this study, the expression of Twik-related acid-sensitive K(+) channel (TASK)-1 [a pH-sensitive potassium channel encoded by the potassium channel, 2-pore domain, subfamily K, member 3 (Kcnk3) gene] correlated highly with Ucp1 expression in obese and cold-exposed mice. In addition, Task1-null mice, compared with their controls, became overweight, mainly because of an increase in white adipose tissue mass and BAT whitening. Task1(-/-)-mouse-derived brown adipocytes, compared with wild-type mouse-derived brown adipocytes, displayed an impaired ß3-adrenergic receptor response that was characterized by a decrease in oxygen consumption, Ucp1 expression, and lipolysis. This phenotype was thought to be caused by an exacerbation of mineralocorticoid receptor (MR) signaling, given that it was mimicked by corticoids and reversed by an MR inhibitor. We concluded that the K(+) channel TASK1 controls the thermogenic activity in brown adipocytes through modulation of ß-adrenergic receptor signaling.


Assuntos
Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Receptores Adrenérgicos beta 3/metabolismo , Receptores de Mineralocorticoides/metabolismo , Transdução de Sinais/fisiologia , Adipócitos Marrons/citologia , Tecido Adiposo Marrom/citologia , Animais , Feminino , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Consumo de Oxigênio/fisiologia , Canais de Potássio de Domínios Poros em Tandem/genética , Receptores de Mineralocorticoides/genética , Termogênese/fisiologia
10.
J Enzyme Inhib Med Chem ; 30(5): 689-721, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25347767

RESUMO

The hypoxic areas of solid cancers represent a negative prognostic factor irrespective of which treatment modality is chosen for the patient. Still, after almost 80 years of focus on the problems created by hypoxia in solid tumours, we still largely lack methods to deal efficiently with these treatment-resistant cells. The consequences of this lack may be serious for many patients: Not only is there a negative correlation between the hypoxic fraction in tumours and the outcome of radiotherapy as well as many types of chemotherapy, a correlation has been shown between the hypoxic fraction in tumours and cancer metastasis. Thus, on a fundamental basis the great variety of problems related to hypoxia in cancer treatment has to do with the broad range of functions oxygen (and lack of oxygen) have in cells and tissues. Therefore, activation-deactivation of oxygen-regulated cascades related to metabolism or external signalling are important areas for the identification of mechanisms as potential targets for hypoxia-specific treatment. Also the chemistry related to reactive oxygen radicals (ROS) and the biological handling of ROS are part of the problem complex. The problem is further complicated by the great variety in oxygen concentrations found in tissues. For tumour hypoxia to be used as a marker for individualisation of treatment there is a need for non-invasive methods to measure oxygen routinely in patient tumours. A large-scale collaborative EU-financed project 2009-2014 denoted METOXIA has studied all the mentioned aspects of hypoxia with the aim of selecting potential targets for new hypoxia-specific therapy and develop the first stage of tests for this therapy. A new non-invasive PET-imaging method based on the 2-nitroimidazole [(18)F]-HX4 was found to be promising in a clinical trial on NSCLC patients. New preclinical models for testing of the metastatic potential of cells were developed, both in vitro (2D as well as 3D models) and in mice (orthotopic grafting). Low density quantitative real-time polymerase chain reaction (qPCR)-based assays were developed measuring multiple hypoxia-responsive markers in parallel to identify tumour hypoxia-related patterns of gene expression. As possible targets for new therapy two main regulatory cascades were prioritised: The hypoxia-inducible-factor (HIF)-regulated cascades operating at moderate to weak hypoxia (<1% O(2)), and the unfolded protein response (UPR) activated by endoplasmatic reticulum (ER) stress and operating at more severe hypoxia (<0.2%). The prioritised targets were the HIF-regulated proteins carbonic anhydrase IX (CAIX), the lactate transporter MCT4 and the PERK/eIF2α/ATF4-arm of the UPR. The METOXIA project has developed patented compounds targeting CAIX with a preclinical documented effect. Since hypoxia-specific treatments alone are not curative they will have to be combined with traditional anti-cancer therapy to eradicate the aerobic cancer cell population as well.


Assuntos
Descoberta de Drogas , Neoplasias/tratamento farmacológico , Animais , Hipóxia Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/patologia , Neoplasias/patologia , Relação Estrutura-Atividade
11.
Mol Oncol ; 18(7): 1719-1738, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38214418

RESUMO

Metformin and IACS-010759 are two distinct antimetabolic agents. Metformin, an established antidiabetic drug, mildly inhibits mitochondrial complex I, while IACS-010759 is a new potent mitochondrial complex I inhibitor. Mitochondria is pivotal in the energy metabolism of cells by providing adenosine triphosphate through oxidative phosphorylation (OXPHOS). Hence, mitochondrial metabolism and OXPHOS become a vulnerability when targeted in cancer cells. Both drugs have promising antitumoral effects in diverse cancers, supported by preclinical in vitro and in vivo studies. We present evidence of their direct impact on cancer cells and their immunomodulatory effects. In clinical studies, while observational epidemiologic studies on metformin were encouraging, actual trial results were not as expected. However, IACS-01075 exhibited major adverse effects, thereby causing a metabolic shift to glycolysis and elevated lactic acid concentrations. Therefore, the future outlook for these two drugs depends on preventive clinical trials for metformin and investigations into the plausible toxic effects on normal cells for IACS-01075.


Assuntos
Complexo I de Transporte de Elétrons , Metformina , Neoplasias , Metformina/uso terapêutico , Metformina/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/imunologia , Complexo I de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Fosforilação Oxidativa/efeitos dos fármacos
12.
J Cell Physiol ; 228(9): 1854-62, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23459996

RESUMO

The efficacy of targeting pH disruption to induce cell death in the acidic and hypoxic tumor microenvironment continues to be assessed. Here we analyzed the impact of varying levels of hypoxia in acidic conditions on fibroblast and tumor cell survival. Across all cell lines tested, hypoxia (1% O(2)) provided protection against acidosis induced cell death compared to normoxia. Meanwhile severe hypoxia (0.1% O(2)) removed this protection and in some cases exacerbated acidosis-induced cell death. Differential survival between cell types during external acidosis correlated with their respective intracellular pH regulating capabilities. Cellular ATP measurements were conducted to determine their contribution to cell survival under these combined stresses. In general, hypoxia (1% O(2)) maintained elevated ATP levels in acidic conditions while severe hypoxia did not. To further explore this interaction we combined acidosis with ATP depletion using 2-deoxyglucose and observed an enhanced rate of cell mortality. Striking results were also observed with hypoxia providing protection against cell death in spite of a severe metabolic stress induced by a combination of acidosis and oligomycin. Finally, we demonstrated that both HIF1α and HIF2α expression were drastically reduced in hypoxic and acidic conditions indicating a sensitivity of this protein to cellular pH conditions. This knockdown of HIF expression by acidosis has implications for the development of therapies targeting the disruption of cellular pH regulation. Our results reinforce the proof of concept that acidosis and metabolic disruption affecting ATP levels could be exploited as a tumor cell killing strategy.


Assuntos
Trifosfato de Adenosina/metabolismo , Hipóxia Celular/fisiologia , Neoplasias/metabolismo , Microambiente Tumoral , Acidose , Trifosfato de Adenosina/fisiologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Cricetinae , Cricetulus , Citoplasma/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias/patologia
13.
Bull Cancer ; 110(4): 412-423, 2023 Apr.
Artigo em Francês | MEDLINE | ID: mdl-36822958

RESUMO

Medulloblastoma (MB) is a malignant brain tumor that mainly affects children. It is rarely found in adults. Among the four groups of MB defined today according to molecular characteristics, group 3 is the least favorable with an overall survival rate of 50 %. Current treatments, based on surgery, radiotherapy, and chemotherapy, are not sufficiently adapted to the different characteristics of the four MB groups. However, the use of new cellular and animal models has opened new doors to interesting therapeutic avenues. In this review, we detail recent advances in MB research, with a focus on the genes and pathways that drive tumorigenesis, with particular emphasis on the animal models that have been developed to study tumor biology, as well as advances in new targeted therapies.


Assuntos
Neoplasias Encefálicas , Neoplasias Cerebelares , Meduloblastoma , Animais , Meduloblastoma/genética , Meduloblastoma/terapia , Meduloblastoma/metabolismo , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/terapia , Neoplasias Cerebelares/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Modelos Animais , Taxa de Sobrevida
14.
Bull Cancer ; 110(3): 331-335, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36775700

RESUMO

This article highlights the presentations from the 2021 scientific meeting of the Club Hematopoiesis and Oncogenesis. This annual meeting focuses on hematopoiesis and oncogenic mechanisms. Various topics were presented: expansion of hematopoietic stem cells with in vivo and ex vivo strategies, the role of the hematopoietic stem cell niches in aging and leukemic resistance, the crossroad between hematology and immunology, the importance of the metabolism in normal hematopoiesis and hematopoietic defects, solid tumors and oncogenesis, the noncoding genome, inflammation in monocyte differentiation and leukemia, and importantly, the recent advances in myeloid malignancies, lymphoid leukemia and lymphoma.


Assuntos
Leucemia , Linfoma , Humanos , Hematopoese/genética , Células-Tronco Hematopoéticas , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia
15.
EMBO Mol Med ; 15(12): e17719, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37966164

RESUMO

Metastatic uveal melanomas are highly resistant to all existing treatments. To address this critical issue, we performed a kinome-wide CRISPR-Cas9 knockout screen, which revealed the LKB1-SIK2 module in restraining uveal melanoma tumorigenesis. Functionally, LKB1 loss enhances proliferation and survival through SIK2 inhibition and upregulation of the sodium/calcium (Na+ /Ca2+ ) exchanger SLC8A1. This signaling cascade promotes increased levels of intracellular calcium and mitochondrial reactive oxygen species, two hallmarks of cancer. We further demonstrate that combination of an SLC8A1 inhibitor and a mitochondria-targeted antioxidant promotes enhanced cell death efficacy in LKB1- and SIK2-negative uveal melanoma cells compared to control cells. Our study also identified an LKB1-loss gene signature for the survival prognostic of patients with uveal melanoma that may be also predictive of response to the therapy combination. Our data thus identify not only metabolic vulnerabilities but also new prognostic markers, thereby providing a therapeutic strategy for particular subtypes of metastatic uveal melanoma.


Assuntos
Melanoma , Neoplasias Uveais , Humanos , Cálcio , Proliferação de Células , Melanoma/tratamento farmacológico , Espécies Reativas de Oxigênio , Neoplasias Uveais/genética , Neoplasias Uveais/patologia
16.
Haematologica ; 97(1): 9-14, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21933857

RESUMO

BACKGROUND: Congenital secondary erythrocytoses are due to deregulation of hypoxia inducible factor resulting in overproduction of erythropoietin. The most common germline mutation identified in the hypoxia signaling pathway is the Arginine 200-Tryptophan mutant of the von Hippel-Lindau tumor suppressor gene, resulting in Chuvash polycythemia. This mutant displays a weak deficiency in hypoxia inducible factor α regulation and does not promote tumorigenesis. Other von Hippel-Lindau mutants with more deleterious effects are responsible for von Hippel-Lindau disease, which is characterized by the development of multiple tumors. Recently, a few mutations in gene for the prolyl hydroxylase domain 2 protein (PHD2) have been reported in cases of congenital erythrocytosis not associated with tumor formation with the exception of one patient with a recurrent extra-adrenal paraganglioma. DESIGN AND METHODS: Five PHD2 variants, four of which were novel, were identified in patients with erythrocytosis. These PHD2 variants were functionally analyzed and compared with the PHD2 mutant previously identified in a patient with polycythemia and paraganglioma. The capacity of PHD2 to regulate the activity, stability and hydroxylation of hypoxia inducible factor α was assessed using hypoxia-inducible reporter gene, one-hybrid and in vitro hydroxylation assays, respectively. RESULTS: This functional comparative study showed that two categories of PHD2 mutants could be distinguished: one category with a weak deficiency in hypoxia inducible factor α regulation and a second one with a deleterious effect; the mutant implicated in tumor occurrence belongs to the second category. CONCLUSIONS: As observed with germline von Hippel-Lindau mutations, there are functional differences between the PHD2 mutants with regards to hypoxia inducible factor regulation. PHD2 mutation carriers do, therefore, need careful medical follow-up, since some mutations must be considered as potential candidates for tumor predisposition.


Assuntos
Mutação em Linhagem Germinativa , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Mutantes/metabolismo , Policitemia/genética , Policitemia/metabolismo , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Adolescente , Adulto , Sequência de Bases , Células Cultivadas , Feminino , Células HEK293 , Humanos , Hidrólise , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia , Masculino , Pessoa de Meia-Idade , Pró-Colágeno-Prolina Dioxigenase/genética , Adulto Jovem
17.
Nature ; 441(7092): 437-43, 2006 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-16724055

RESUMO

Tumour cells emerge as a result of genetic alteration of signal circuitries promoting cell growth and survival, whereas their expansion relies on nutrient supply. Oxygen limitation is central in controlling neovascularization, glucose metabolism, survival and tumour spread. This pleiotropic action is orchestrated by hypoxia-inducible factor (HIF), which is a master transcriptional factor in nutrient stress signalling. Understanding the role of HIF in intracellular pH (pH(i)) regulation, metabolism, cell invasion, autophagy and cell death is crucial for developing novel anticancer therapies. There are new approaches to enforce necrotic cell death and tumour regression by targeting tumour metabolism and pH(i)-control systems.


Assuntos
Hipóxia Celular , Neoplasias/metabolismo , Neoplasias/patologia , Oxigênio/metabolismo , Transdução de Sinais , Animais , Humanos , Neovascularização Patológica , Proteínas Quinases/metabolismo , Serina-Treonina Quinases TOR
18.
J Nephrol ; 35(2): 527-534, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34468976

RESUMO

BACKGROUND AND AIMS: Despite close follow-up of patients with native arteriovenous fistulas (AVFs), up to 10% experience thrombosis each year. The OSMOSIS Study (Osteopontin as a Marker of Stenosis) tested the hypothesis that the systemic osteopontin level, a pro-inflammatory mediator related to vascular remodelling and intimal hyperplasia, increases in AVF stenosis, and may be used in clinical surveillance. METHODS: Our cross-sectional study compared the level of plasmatic osteopontin (pOPN) between patients with a well-functioning AVF (control group) and patients who required revision of their AVF due to stenosis (stenosis group). Blood samples were collected before dialysis (control group) or before intervention (stenosis group) from the AVF arm, and from the opposite arm as a within-subject control. pOPN level was measured by enzyme-linked immunosorbent assay. RESULTS: A total of 76 patients were included in the study. Baseline characteristics were similar between the groups (mean age, 70 years; men, 63%; AVF duration, 39 months), apart from prevalence of type 2 diabetes (T2D) (control group, 33%; stenosis group, 57%; p = 0.04). pOPN levels were similar between the AVF arm and the contralateral arm (551 ± 42 ng/mL vs. 521 ± 41 ng/mL, respectively, p = 0.11, paired t-test). Patients in the stenosis group displayed a higher pOPN level than patients in the control group (650.2 ± 59.8 ng/mL vs. 460.5 ± 61.2, respectively, p = 0.03; two-way ANOVA). T2D was not identified as an associated factor in a multivariate analysis (p = 0.50). CONCLUSIONS: The level of pOPN in hemodialysis patients was associated with the presence of AVF stenosis requiring intervention. Thus, its potential as a diagnostic biomarker should be assessed in a vascular access surveillance program.


Assuntos
Derivação Arteriovenosa Cirúrgica , Diabetes Mellitus Tipo 2 , Idoso , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Estudos de Casos e Controles , Estudos Transversais , Humanos , Masculino , Osmose , Osteopontina , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
19.
Mar Environ Res ; 180: 105709, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35988349

RESUMO

The Pacific oyster Crassostrea gigas is established in the marine intertidal zone, experiencing rapid and highly dynamic environmental changes throughout the tidal cycle. Depending on the bathymetry, oysters face oxygen deprivation, lack of nutrients, and high changes in temperature during alternation of the cycles of emersion/immersion. Here we showed that intertidal oysters at a bathymetry level of 3 and 5 m delayed by ten days the onset of mortality associated with Pacific Oyster Mortality Syndrome (POMS) as compared to subtidal oysters. Intertidal oysters presented a lower growth but similar energetic reserves to subtidal oysters but induced proteomic changes indicative of a boost in metabolism, inflammation, and innate immunity that may have improved their resistance during infection with the Ostreid herpes virus. Our work highlights that intertidal harsh environmental conditions modify host-pathogen interaction and improve oyster health. This study opens new perspectives on oyster farming for mitigation strategies based on tidal height.


Assuntos
Crassostrea , Herpesviridae , Animais , Interações Hospedeiro-Patógeno , Imunidade Inata , Proteômica
20.
FEBS J ; 289(18): 5516-5526, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34817127

RESUMO

The 4th International meeting Metabolism and Cancer initially programed to take place in Bordeaux (France) was held virtually on May 27-29, 2021. The three-day event was followed by around 600 participants daily from 47 countries around the world. The meeting hosted 21 speakers including selected talks and a keynote lecture from the Nobel Prize winner Sir Peter J. Ratcliffe (Oxford, UK). Presentations and discussions were divided in four scientific sessions: (a) Redox and energy metabolism (b) Redox and hypoxia (c) Metabolic profiling and epigenetic control and (d) Signalling, fuelling and metabolism in cancer and a general public session on cancer and nutrition. This report summarises the presentations and outcomes of the 4th annual Metabolism and Cancer symposium. We provide here a summary of the scientific highlights of this exciting meeting.


Assuntos
Metabolismo , Neoplasias , Humanos , Neoplasias/metabolismo , Sociedades Médicas
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