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1.
Chemosphere ; 346: 140535, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37923018

RESUMO

The worldwide and intensive use of phytosanitary compounds results in environmental and food contamination by chemical residues. Human exposure to multiple pesticide residues is a major health issue. Considering that the liver is not only the main organ for metabolizing pesticides but also a major target of toxicities induced by xenobiotics, we studied the effects of a mixture of 7 pesticides (chlorpyrifos-ethyl, dimethoate, diazinon, iprodione, imazalil, maneb, mancozeb) often detected in food samples. Effects of the mixture was investigated using metabolically competent HepaRG cells and human hepatocytes in primary culture. We report the strong cytotoxicity of the pesticide mixture towards hepatocytes-like HepaRG cells and human hepatocytes upon acute and chronic exposures at low concentrations extrapolated from the Acceptable Daily Intake (ADI) of each compound. Unexpectedly, we demonstrated that the manganese (Mn)-containing dithiocarbamates (DTCs) maneb and mancozeb were solely responsible for the cytotoxicity induced by the mixture. The mechanism of cell death involved the induction of oxidative stress, which led to cell death by intrinsic apoptosis involving caspases 3 and 9. Importantly, this cytotoxic effect was found only in cells metabolizing these pesticides. Herein, we unveil a novel mechanism of toxicity of the Mn-containing DTCs maneb and mancozeb through their metabolization in hepatocytes generating the main metabolite ethylene thiourea (ETU) and the release of Mn leading to intracellular Mn overload and depletion in zinc (Zn). Alteration of the Mn and Zn homeostasis provokes the oxidative stress and the induction of apoptosis, which can be prevented by Zn supplementation. Our data demonstrate the hepatotoxicity of Mn-containing fungicides at very low doses and unveil their adverse effect in disrupting Mn and Zn homeostasis and triggering oxidative stress in human hepatocytes.


Assuntos
Fungicidas Industriais , Maneb , Praguicidas , Zineb , Humanos , Maneb/toxicidade , Manganês/toxicidade , Manganês/metabolismo , Praguicidas/toxicidade , Zineb/toxicidade , Fungicidas Industriais/toxicidade , Fungicidas Industriais/análise , Apoptose , Estresse Oxidativo , Zinco/metabolismo , Hepatócitos/metabolismo , Etilenos , Homeostase
2.
Biomolecules ; 13(12)2023 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-38136561

RESUMO

Amyotrophic lateral sclerosis (ALS) is the most common neurodegenerative motor neuron disease and remains misunderstood with a difficult diagnosis and prognosis. The implication of the immune system is recognized in ALS pathophysiology, hence the interest in leucocyte count as lymphocytes and neutrophils. The neutrophil-to-lymphocyte ratio (NLR) has recently been used as a prognosis factor to assess the progression of ALS. Thus, the aim of this study was to analyze the evolution of the NLR during disease evolution in a French cohort of ALS patients and its relation with survival. In this monocentric retrospective study, clinical parameters and NLR were collected in ALS patients followed at the University Hospital of Tours (France). ALS patients were subdivided into three groups regarding their NLR value at inclusion: group 1 (NLR < 2); group 2 (NLR: 2-3); group 3 (NLR > 3). A comparison of qualitative and quantitative clinical and biological variables between NLR groups was performed. Then, Cox regressions were carried out to determine the association of NLR with survival. We observed a significant correlation of NLR with ALSFRS-r score (p < 0.0001) and with vital forced capacity (p = 0.0004) at inclusion. We observed that increased NLR at diagnosis is associated with decreased ALS patients' survival.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/diagnóstico , Neutrófilos , Estudos Retrospectivos , Prognóstico , Progressão da Doença , Linfócitos
3.
Hemasphere ; 7(11): e960, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37908859

RESUMO

Childhood immune thrombocytopenia (ITP) is a rare autoimmune disorder characterized by isolated thrombocytopenia. Prolonged ITP (persistent and chronic) leads to a reduced quality of life for children in many domains. To provide optimal support for children, with ITP, it is important to be able to predict those who will develop prolonged ITP. This study aimed to develop a mathematical model based on platelet recovery that allows the early prediction of prolonged ITP. In this retrospective study, we used platelet counts from the 6 months following the diagnosis of ITP to model the kinetics of change in platelet count using a pharmacokinetic-pharmacodynamic model. In a learning set (n = 103), platelet counts were satisfactorily described by our kinetic model. The Kheal parameter, which describes spontaneous platelet recovery, allowed a distinction between acute and prolonged ITP with an area under the curve (AUC) of 0.74. In a validation set (n = 58), spontaneous platelet recovery was robustly predicted using platelet counts from 15 (AUC = 0.76) or 30 (AUC = 0.82) days after ITP diagnosis. In our model, platelet recovery quantified using the kheal parameter allowed prediction of the clinical course of ITP. Future prospective studies are needed to improve the predictivity of this model, in particular, by combining it with the predictive scores previously reported in the literature.

4.
EJHaem ; 4(3): 844-847, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37601847

RESUMO

Chronic myelomonocytic leukemia (CMML) is a myelodysplastic/myeloproliferative neoplasm characterized by the infiltration of blood and bone marrow by immature monocytes, in which extra-hematopoietic localization is uncommon. We report the case of a 69-year-old-man with highly likely ectopic brain CMML involvement by MRI. Without the possibility of cerebral biopsy and with a negative infectious disease assessment, high-dose cytarabine-based chemotherapy was successfully administered. The favorable evolution in this case highlights the potential benefit of such treatment, even without a cerebral biopsy to confirm the disease. This case can aid clinical decision-making in the future.

5.
Stem Cells Transl Med ; 12(10): 676-688, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37616262

RESUMO

In a steady state, hematopoietic stem cells (HSC) exhibit very low levels of reactive oxygen species (ROS). Upon stress, HSC get activated and enter into proliferation and differentiation process to ensure blood cell regeneration. Once activated, their levels of ROS increase, as messengers to mediate their proliferation and differentiation programs. However, at the end of the stress episode, ROS levels need to return to normal to avoid HSC exhaustion. It was shown that antioxidants can prevent loss of HSC self-renewal potential in several contexts such as aging or after exposure to low doses of irradiation suggesting that antioxidants can be used to maintain HSC functional properties upon culture-induced stress. Indeed, in humans, HSC are increasingly used for cell and gene therapy approaches, requiring them to be cultured for several days. As expected, we show that a short culture period leads to drastic defects in HSC functional properties. Moreover, a switch of HSC transcriptional program from stemness to differentiation was evidenced in cultured HSC. Interestingly, cultured-HSC treated with 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (4-hydroxy-TEMPO or Tempol) exhibited a higher clonogenic potential in secondary colony forming unit cell (CFU-C) assay and higher reconstitution potential in xenograft model, compared to untreated cultured-HSC. By transcriptomic analyses combined with serial CFU-C assays, we show that Tempol, which mimics superoxide dismutase, protects HSC from culture-induced stress partly through VEGFα signaling. Thus, we demonstrate that adding Tempol leads to the protection of HSC functional properties during ex vivo culture.


Assuntos
Antioxidantes , Células-Tronco Hematopoéticas , Humanos , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio , Óxidos N-Cíclicos/farmacologia , Células Cultivadas , Proliferação de Células
6.
Clin Immunol ; 255: 109730, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37562724

RESUMO

Aging is associated with bone marrow (BM) inflammaging and, in some individuals, with the onset of clonal hematopoiesis (CH) of indeterminate potential. In this study conducted on 94 strictly healthy volunteers (18 to 80 yo), we measured BM and peripheral blood (PB) plasma levels of 49 hematopoietic and inflammatory cytokines. With aging, 7 cytokines increased in BM (FLT3L, CXCL9, HGF, FGF-2, CCL27, IL-16, IL-18) and 8 decreased (G-CSF, TNF, IL-2, IL-15, IL-17A, CCL7, IL-4, IL-10). In PB, 10 cytokines increased with age (CXCL9, FLT3L, CCL27, CXCL10, HGF, CCL11, IL-16, IL-6, IL-1 beta, CCL2). CH was associated with higher BM levels of MIF and IL-1 beta, lower BM levels of IL-9 and IL-5 and higher PB levels of IL-15, VEGF-A, IL-2, CXCL8, CXCL1 and G-CSF. These reference values provide a useful tool to investigate anomalies related to inflammaging and potentially leading to the onset of age-related myeloid malignancies or inflammatory conditions.


Assuntos
Medula Óssea , Citocinas , Humanos , Interleucina-1beta , Interleucina-15 , Hematopoiese Clonal , Interleucina-16 , Interleucina-2 , Fator Estimulador de Colônias de Granulócitos , Células da Medula Óssea , Hematopoese
7.
Biomedicines ; 10(6)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35740329

RESUMO

Diverse biomarkers and pathological alterations have been found in muscle of patients with Amyotrophic lateral sclerosis (ALS), but the relation between such alterations and dysfunction in energetic metabolism remains to be investigated. We established the metabolome of muscle and serum of ALS patients and correlated these findings with the clinical status and pathological alterations observed in the muscle. We obtained data from 20 controls and 17 ALS patients (disease duration: 9.4 ± 6.8 months). Multivariate metabolomics analysis identified a distinct serum metabolome for ALS compared to controls (p-CV-ANOVA < 0.035) and revealed an excellent discriminant profile for muscle metabolome (p-CV-ANOVA < 0.0012). Citramalate was discriminant for both muscle and serum. High lauroylcarnitine levels in muscle were associated with low Forced Vital Capacity. Transcriptomics analysis of key antioxidant enzymes showed an upregulation of SOD3 (p = 0.0017) and GLRX2(1) (p = 0.0022) in ALS muscle. Analysis of mitochondrial enzymatic activity in muscle revealed higher complex II/CS (p = 0.04) and lower LDH (p = 0.03) activity in ALS than in controls. Our study showed, for the first time, a global dysfunction in the muscle of early-stage ALS patients. Furthermore, we identified novel metabolites to be employed as biomarkers for diagnosis and prognosis of ALS patients.

8.
Sci Rep ; 12(1): 9748, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35697729

RESUMO

The treatment of acute myeloid leukemia (AML) with unfavorable cytogenetics treatment remains a challenge. We previously established that ex vivo exposure of AML blasts to eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), or fish oil emulsion (FO) induces Nrf2 pathway activation, metabolic switch, and cell death. The FILO group launched a pilot clinical study to evaluate the feasibility, safety, and efficacy of the adjunction of a commercial FO emulsion to 3 + 7 in untreated AML with unfavorable cytogenetics. The primary objective was complete response (CR). Thirty patients were included. FO administration raised the plasma levels of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids (p < 0.001). The pharmacokinetics of cytarabine and daunorubicin were unaffected. A historical comparison to the LAM2001 trial (Lioure et al. Blood 2012) found a higher frequency of grade 3 serious adverse events, with no drug-related unexpected toxicity. The CR rate was 77%, and the partial response (PR) 10%, not significantly superior to that of the previous study (CR 72%, PR 1%). RT-qPCR analysis of Nrf2 target genes and antioxidant enzymes did not show a significant in vivo response. Overall, FO emulsion adjunction to 3 + 7 is feasible. An improvement in CR was not shown in this cohort of high-risk patients. The present data does not support the use of FO in adjunction with 3 + 7 in high-risk AML patients.ClinicalTrials.gov identifier: NCT01999413.


Assuntos
Citarabina , Leucemia Mieloide Aguda , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Ácidos Docosa-Hexaenoicos/uso terapêutico , Ácido Eicosapentaenoico , Emulsões/uso terapêutico , Estudos de Viabilidade , Óleos de Peixe/uso terapêutico , Humanos , Quimioterapia de Indução , Leucemia Mieloide Aguda/genética , Fator 2 Relacionado a NF-E2/genética
9.
Cancers (Basel) ; 14(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35626090

RESUMO

Acute myeloid leukemia (AML) is characterized by the accumulation of undifferentiated blast cells in the bone marrow and blood. In most cases of AML, relapse frequently occurs due to resistance to chemotherapy. Compelling research results indicate that drug resistance in cancer cells is highly dependent on the intracellular levels of reactive oxygen species (ROS). Modulating ROS levels is therefore a valuable strategy to overcome the chemotherapy resistance of leukemic cells. In this study, we evaluated the efficiency of diphenyleneiodonium (DPI)-a well-known inhibitor of ROS production-in targeting AML cells. Results showed that although inhibiting cytoplasmic ROS production, DPI also triggered an increase in the mitochondrial ROS levels, caused by the disruption of the mitochondrial respiratory chain. We also demonstrated that DPI blocks mitochondrial oxidative phosphorylation (OxPhos) in a dose-dependent manner, and that AML cells with high OxPhos status are highly sensitive to treatment with DPI, which synergizes with the chemotherapeutic agent cytarabine (Ara-C). Thus, our results suggest that targeting mitochondrial function with DPI might be exploited to target AML cells with high OxPhos status.

10.
Cell Mol Life Sci ; 79(6): 284, 2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35526196

RESUMO

BACKGROUND AND AIMS: Recent evidences highlight a role of the mitochondria calcium homeostasis in the development of colorectal cancer (CRC). To overcome treatment resistance, we aimed to evaluate the role of the mitochondrial sodium-calcium-lithium exchanger (NCLX) and its targeting in CRC. We also identified curcumin as a new inhibitor of NCLX. METHODS: We examined whether curcumin and pharmacological compounds induced the inhibition of NCLX-mediated mitochondrial calcium (mtCa2+) extrusion, the role of redox metabolism in this process. We evaluated their anti-tumorigenic activity in vitro and in a xenograft mouse model. We analyzed NCLX expression and associations with survival in The Cancer Genome Atlas (TCGA) dataset and in tissue microarrays from 381 patients with microsatellite instability (MSI)-driven CRC. RESULTS: In vitro, curcumin exerted strong anti-tumoral activity through its action on NCLX with mtCa2+ and reactive oxygen species overload associated with a mitochondrial membrane depolarization, leading to reduced ATP production and apoptosis. NCLX inhibition with pharmacological and molecular approaches reproduced the effects of curcumin. NCLX inhibitors decreased CRC tumor growth in vivo. Both transcriptomic analysis of TCGA dataset and immunohistochemical analysis of tissue microarrays demonstrated that higher NCLX expression was associated with MSI status, and for the first time, NCLX expression was significantly associated with recurrence-free survival. CONCLUSIONS: Our findings highlight a novel anti-tumoral mechanism of curcumin through its action on NCLX and mitochondria calcium overload that could benefit for therapeutic schedule of patients with MSI CRC.


Assuntos
Neoplasias Colorretais , Curcumina , Instabilidade de Microssatélites , Trocador de Sódio e Cálcio , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Curcumina/farmacologia , Humanos , Camundongos , Repetições de Microssatélites , Proteínas Mitocondriais/metabolismo , Trocador de Sódio e Cálcio/antagonistas & inibidores
11.
EMBO J ; 41(12): e108306, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35506364

RESUMO

Influenza virus infection causes considerable morbidity and mortality, but current therapies have limited efficacy. We hypothesized that investigating the metabolic signaling during infection may help to design innovative antiviral approaches. Using bronchoalveolar lavages of infected mice, we here demonstrate that influenza virus induces a major reprogramming of lung metabolism. We focused on mitochondria-derived succinate that accumulated both in the respiratory fluids of virus-challenged mice and of patients with influenza pneumonia. Notably, succinate displays a potent antiviral activity in vitro as it inhibits the multiplication of influenza A/H1N1 and A/H3N2 strains and strongly decreases virus-triggered metabolic perturbations and inflammatory responses. Moreover, mice receiving succinate intranasally showed reduced viral loads in lungs and increased survival compared to control animals. The antiviral mechanism involves a succinate-dependent posttranslational modification, that is, succinylation, of the viral nucleoprotein at the highly conserved K87 residue. Succinylation of viral nucleoprotein altered its electrostatic interactions with viral RNA and further impaired the trafficking of viral ribonucleoprotein complexes. The finding that succinate efficiently disrupts the influenza replication cycle opens up new avenues for improved treatment of influenza pneumonia.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Infecções por Orthomyxoviridae , Pneumonia , Animais , Antivirais/farmacologia , Humanos , Vírus da Influenza A Subtipo H3N2/metabolismo , Camundongos , Proteínas do Nucleocapsídeo , Nucleoproteínas/metabolismo , Ácido Succínico/metabolismo , Ácido Succínico/farmacologia , Ácido Succínico/uso terapêutico , Replicação Viral
13.
J Investig Med ; 70(4): 934-938, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35292508

RESUMO

Iron metabolism is tightly linked to infectious and inflammatory signals through hepcidin synthesis. To date, iron homeostasis during SARS-CoV-2 infection has not yet been described. The aim of this study is to characterize the hepcidin and erythroid regulators (growth differentiation factor 15 (GDF-15) and erythroferrone (ERFE)) by measuring concentrations in plasma in context of COVID-19 disease.We performed a single-center observational study of patients with COVID-19 to evaluate concentrations of main regulatory proteins involved in iron homeostasis, namely: hepcidin, ERFE and GDF-15. SARS-CoV-2 infection (COVID-19+) was defined by a positive RT-PCR. Sixteen patients with COVID-19+ were gender-matched and age-matched to 16 patients with a sepsis unrelated to SARS-CoV-2 (COVID-19-) and were compared with non-parametric statistic test.Clinical and hematological parameters, plasma iron, transferrin, transferrin saturation, ferritin, soluble transferrin receptor and C reactive protein were not statistically different between both groups. Median plasma hepcidin concentrations were higher in the COVID-19+ group (44.1 (IQR 16.55-70.48) vs 14.2 (IQR 5.95-18.98) nmol/L, p=0.003), while median ERFE and GDF-15 concentrations were lower in the COVID-19+ group (0.16 (IQR 0.01-0.73) vs 0.89 (IQR 0.19-3.82) ng/mL, p=0.035; 2003 (IQR 1355-2447) vs 4713 (IQR 2082-7774) pg/mL, p=0015), respectively) compared with the COVID-19- group.This is the first study reporting lower ERFE and GDF-15 median concentrations in patients with COVID-19+ compared with patients with COVID-19-, associated with an increased median concentration of hepcidin in the COVID-19+ group compared with COVID19- group.


Assuntos
COVID-19 , Hepcidinas , COVID-19/metabolismo , Fator 15 de Diferenciação de Crescimento , Hepcidinas/metabolismo , Humanos , Ferro/metabolismo , SARS-CoV-2 , Transferrina/metabolismo
14.
Cancer Gene Ther ; 29(8-9): 1263-1275, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35194200

RESUMO

DNA methylation, a major biological process regulating the transcription, contributes to the pathophysiology of hematologic malignancies, and hypomethylating agents are commonly used to treat myelodysplastic syndromes (MDS) and acute myeloid leukemias (AML). In these diseases, bone marrow mesenchymal stromal cells (MSCs) play a key supportive role through the production of various signals and interactions. The DNA methylation status of MSCs, likely to reflect their functionality, might be relevant to understand their contribution to the pathophysiology of these diseases. Consequently, the aim of our study was to analyze the modifications of DNA methylation profiles of MSCs induced by MDS or AML. MSCs from MDS/AML patients were characterized via 5-methylcytosine quantification, gene expression profiles of key regulators of DNA methylation, identification of differentially methylated regions (DMRs) by methylome array, and quantification of DMR-coupled genes expression. MDS and AML-MSCs displayed global hypomethylation and under-expression of DNMT1 and UHRF1. Methylome analysis revealed aberrant methylation profiles in all MDS and in a subgroup of AML-MSCs. This aberrant methylation was preferentially found in the sequence of homeobox genes, especially from the HOX family (HOXA1, HOXA4, HOXA5, HOXA9, HOXA10, HOXA11, HOXB5, HOXC4, and HOXC6), and impacted on their expression. These results highlight modifications of DNA methylation in MDS/AML-MSCs, both at global and focal levels dysregulating the expression of HOX genes well known for their involvement in leukemogenesis. Such DNA methylation in MSCs could be the consequence of the malignant disease or could participate in its development through defective functionality or exosomal transfer of HOX transcription factors from MSCs to hematopoietic cells.


Assuntos
Leucemia Mieloide Aguda , Células-Tronco Mesenquimais , Síndromes Mielodisplásicas , Medula Óssea/patologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Metilação de DNA , Genes Homeobox/genética , Humanos , Leucemia Mieloide Aguda/patologia , Células-Tronco Mesenquimais/metabolismo , Síndromes Mielodisplásicas/genética , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/metabolismo
15.
Pharmacol Res ; 177: 106097, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35085755

RESUMO

Tumor microenvironment plays an important role in melanoma progression. Recent studies reported endothelial cells (EC) are involved in endothelial-to-mesenchymal transition (EndMT). During this phenotypic switch, EC progressively lose their endothelial markers and acquire mesenchymal properties. Depending on their concentration, reactive oxygen species (ROS) can control tumor growth. In EC, ROS are mainly produced by NAPDH oxidases (NOX) such as NOX1 and NOX2. The aim of the present study was to determine the role of these enzymes in EndMT induced by conditioned media (CM) from SK-MEL 28 melanoma cells. The capacity of CM to induce EndMT in HUVEC after 24 h, 48 h or 72 h has been evaluated by following endothelial HUVECs proliferation, migration and their capacity to form capillary on ECMgel®. Furthermore, EndMT was confirmed by western blot and flow cytometry. To determine the role of NOX in EndMT, specific NOX1 and/or NOX2 inhibitors has been tested. TGF-ß2 + /- IL-1ß was used as positive control. ROS production was determined through DCFDA assay. An altered endothelial phenotype was found in CM-treated HUVECs. This phenotypic modification was correlated with a decrease in both capillary formation on ECMgel® and cell proliferation and an increase in cell migration. Exposure to CM for 48 h significantly enhanced intracellular HUVECs ROS production and this increase was prevented by the dual pharmacological inhibition of NOX1 and NOX2. Furthermore, inhibition of NOX1/2 also leads to a partial reversion of CM-induced EndMT. These data confirmed the role of NOX1 and NOX2 in EndMT induced by melanoma cancer cell secretome.


Assuntos
Células Endoteliais , Melanoma , Proliferação de Células , Meios de Cultivo Condicionados/farmacologia , Transição Epitelial-Mesenquimal , Humanos , Espécies Reativas de Oxigênio , Microambiente Tumoral
17.
Front Immunol ; 12: 766275, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858421

RESUMO

Knowledge about the hematopoietic niche has evolved considerably in recent years, in particular through in vitro analyzes, mouse models and the use of xenografts. Its complexity in the human bone marrow, in particular in a context of hematological malignancy, is more difficult to decipher by these strategies and could benefit from the knowledge acquired on the niches of solid tumors. Indeed, some common features can be suspected, since the bone marrow is a frequent site of solid tumor metastases. Recent research on solid tumors has provided very interesting information on the interactions between tumoral cells and their microenvironment, composed notably of mesenchymal, endothelial and immune cells. This review thus focuses on recent discoveries on tumor niches that could help in understanding hematopoietic niches, with special attention to 4 particular points: i) the heterogeneity of carcinoma/cancer-associated fibroblasts (CAFs) and mesenchymal stem/stromal cells (MSCs), ii) niche cytokines and chemokines, iii) the energy/oxidative metabolism and communication, especially mitochondrial transfer, and iv) the vascular niche through angiogenesis and endothelial plasticity. This review highlights actors and/or pathways of the microenvironment broadly involved in cancer processes. This opens avenues for innovative therapeutic opportunities targeting not only cancer stem cells but also their regulatory tumor niche(s), in order to improve current antitumor therapies.


Assuntos
Microambiente Tumoral , Animais , Fibroblastos Associados a Câncer , Comunicação Celular , Citocinas , Endotélio Vascular , Humanos , Células-Tronco Mesenquimais , Neoplasias , Neovascularização Patológica
18.
Cancers (Basel) ; 13(22)2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34830855

RESUMO

(1) Background: The impact of occupational exposure to high doses of pesticides on hematologic disorders is widely studied. Yet, lifelong exposure to low doses of pesticides, and more particularly their cocktail effect, although poorly known, could also participate to the development of such hematological diseases as myelodysplastic syndrome (MDS) in elderly patients. (2) Methods: In this study, a cocktail of seven pesticides frequently present in water and food (maneb, mancozeb, iprodione, imazalil, chlorpyrifos ethyl, diazinon and dimethoate), as determined by the European Food Safety Authority, were selected. Their in vitro effects at low-doses on primary BM-MSCs from healthy volunteers were examined. (3) Results: Exposure of normal BM-MSCs to pesticides for 21 days inhibited cell proliferation and promoted DNA damage and senescence. Concomitantly, these cells presented a decrease in aldehyde dehydrogenase 2 (ALDH2: mRNA, protein and enzymatic activity) and an increase in acetaldehyde levels. Pharmacological inhibition of ALDH2 with disulfiram recapitulated the alterations induced by exposure to low doses of pesticides. Moreover, BM-MSCs capacity to support primitive hematopoiesis was significantly altered. Similar biological abnormalities were found in primary BM-MSCs derived from MDS patients. (4) Conclusions: these results suggest that ALDH2 could participate in the pathophysiology of MDS in elderly people long exposed to low doses of pesticides.

19.
J Med Case Rep ; 15(1): 463, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34538261

RESUMO

BACKGROUND: In ineffective erythropoiesis, hepcidin synthesis is suppressed by erythroid regulators, namely erythroferrone and growth differentiation factor-15. For the first time, the hypothesis that iron overload in megaloblastic anemia may be related to ineffective erythropoiesis is explored by describing the kinetics of hepcidin, erythroferrone, and growth differentiation factor-15 levels in a patient diagnosed with megaloblastic anemia associated with iron overload. CASE PRESENTATION: An 81-year-old Caucasian male was admitted for fatigue. He had type-2 diabetes previously treated with metformin, ischemic cardiac insufficiency, and stage-3 chronic kidney disease. Vitiligo was observed on both hands. Biological tests revealed normocytic non-regenerative anemia associated with hemolysis, thrombocytopenia, and elevated sideremia, ferritin, and transferrin saturation levels. Megaloblastic anemia was confirmed with undetectable blood vitamin B12 and typical cytological findings like hyper-segmented neutrophils in blood and megaloblasts in bone marrow. The patient received vitamin B12 supplementation. At 3 months, biological parameters reached normal values. Hepcidin kinetics from diagnosis to 3 months inversely correlated with those of erythroferrone and growth differentiation factor-15. CONCLUSIONS: This case suggests that iron-overload mechanisms of dyserythropoietic anemias may apply to megaloblastic anemias.


Assuntos
Anemia Megaloblástica , Anemia , Sobrecarga de Ferro , Idoso de 80 Anos ou mais , Anemia Megaloblástica/diagnóstico , Anemia Megaloblástica/tratamento farmacológico , Eritropoese , Humanos , Ferro , Sobrecarga de Ferro/tratamento farmacológico , Masculino
20.
J Med Case Rep ; 15(1): 368, 2021 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-34303369

RESUMO

BACKGROUND: Chronic myelomonocytic leukemia is a myelodysplastic/myeloproliferative neoplasm characterized by the infiltration of blood and bone marrow by immature monocytes. Cerebral localization of chronic myelomonocytic leukemia has never been described. CASE PRESENTATION: We report the case of a Caucasian 59 year-old man with multiorgan chronic myelomonocytic leukemia infiltration, associated with uncommon brain involvement. There was no evidence of evolution to acute myeloid leukemia. The evidence of cerebral infiltration by chronic myelomonocytic leukemia was made after autopsy. CONCLUSIONS: The fatal outcome of the patient raises the question of the potential benefit of early specific treatment, such as demethylating agents or intensive chemotherapy. Sharing such images of atypical and rapidly evolving chronic myelomonocytic leukemia and the disease history may help clinical decision-making in the future.


Assuntos
Leucemia Mieloide Aguda , Leucemia Mielomonocítica Crônica , Medula Óssea , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade
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