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1.
Nat Commun ; 15(1): 1879, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424041

RESUMO

Cancer cells integrate multiple biosynthetic demands to drive unrestricted proliferation. How these cellular processes crosstalk to fuel cancer cell growth is still not fully understood. Here, we uncover the mechanisms by which the transcription factor Carbohydrate responsive element binding protein (ChREBP) functions as an oncogene during hepatocellular carcinoma (HCC) development. Mechanistically, ChREBP triggers the expression of the PI3K regulatory subunit p85α, to sustain the activity of the pro-oncogenic PI3K/AKT signaling pathway in HCC. In parallel, increased ChREBP activity reroutes glucose and glutamine metabolic fluxes into fatty acid and nucleic acid synthesis to support PI3K/AKT-mediated HCC growth. Thus, HCC cells have a ChREBP-driven circuitry that ensures balanced coordination between PI3K/AKT signaling and appropriate cell anabolism to support HCC development. Finally, pharmacological inhibition of ChREBP by SBI-993 significantly suppresses in vivo HCC tumor growth. Overall, we show that targeting ChREBP with specific inhibitors provides an attractive therapeutic window for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Hepáticas/metabolismo , Transdução de Sinais , Carcinogênese , Proliferação de Células , Linhagem Celular Tumoral
2.
Cancer Chemother Pharmacol ; 91(5): 413-425, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37010549

RESUMO

PURPOSE: The objective was to develop a pharmacokinetic-pharmacodynamic (PK-PD) model linking everolimus and sorafenib exposure with biomarker dynamics and progression-free survival (PFS) based on data from EVESOR trial in patients with solid tumors treated with everolimus and sorafenib combination therapy and to simulate alternative dosing schedules for sorafenib. PATIENTS AND METHODS: Everolimus (5-10 mg once daily, qd) and sorafenib (200-400 mg twice daily, bid) were administered according to four different dosing schedules in 43 solid tumor patients. Rich PK and PD sampling for serum angiogenesis biomarkers was performed. Baseline activation of RAS/RAF/ERK (MAPK) pathway was assessed by quantification of mRNA specific gene panel in tumor biopsies. The PK-PD modeling was performed using NONMEM® software. RESULTS: An indirect response PK-PD model linking sorafenib plasma exposure with soluble vascular endothelial growth factor receptor 2 (sVEGFR2) dynamics was developed. Progression-free survival (PFS) was described by a parametric time-to-event model. Higher decreases in sVEGFR2 at day 21 and higher baseline activation of MAPK pathway were associated with longer PFS (p = 0.002 and p = 0.007, respectively). The simulated schedule sorafenib 200 mg bid 5 days-on/2 days-off + continuous everolimus 5 mg qd was associated with median PFS of 4.3 months (95% CI 1.6-14.4), whereas the median PFS in the EVESOR trial was 3.6 months (95% CI 2.7-4.2, n = 43). CONCLUSION: Sorafenib 200 mg bid 5 days-on/2 days-off + everolimus 5 mg qd continuous was selected for an additional arm of EVESOR trial to evaluate whether this simulated schedule is associated with higher clinical benefit. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01932177.


Assuntos
Everolimo , Neoplasias , Humanos , Sorafenibe/uso terapêutico , Intervalo Livre de Progressão , Fator A de Crescimento do Endotélio Vascular , Niacinamida , Compostos de Fenilureia , Resultado do Tratamento , Neoplasias/tratamento farmacológico , Biomarcadores
3.
Hepatology ; 77(4): 1319-1334, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36029129

RESUMO

BACKGROUND AND AIMS: Receptor-interacting protein kinase 3 (RIPK3) mediates NAFLD progression, but its metabolic function is unclear. Here, we aimed to investigate the role of RIPK3 in modulating mitochondria function, coupled with lipid droplet (LD) architecture in NAFLD. APPROACH AND RESULTS: Functional studies evaluating mitochondria and LD biology were performed in wild-type (WT) and Ripk3-/- mice fed a choline-deficient, amino acid-defined (CDAA) diet for 32 and 66 weeks and in CRISPR-Cas9 Ripk3 -null fat-loaded immortalized hepatocytes. The association between hepatic perilipin (PLIN) 1 and 5, RIPK3, and disease severity was also addressed in a cohort of patients with NAFLD and in PLIN1 -associated familial partial lipodystrophy. Ripk3 deficiency rescued impairment in mitochondrial biogenesis, bioenergetics, and function in CDAA diet-fed mice and fat-loaded hepatocytes. Ripk3 deficiency was accompanied by a strong upregulation of antioxidant systems, leading to diminished oxidative stress upon fat loading both in vivo and in vitro. Strikingly, Ripk3-/- hepatocytes displayed smaller size LD in higher numbers than WT cells after incubation with free fatty acids. Ripk3 deficiency upregulated adipocyte and hepatic levels of LD-associated proteins PLIN1 and PLIN5. PLIN1 upregulation controlled LD structure and diminished mitochondrial stress upon free fatty acid overload in Ripk3-/- hepatocytes and was associated with diminished human NAFLD severity. Conversely, a pathogenic PLIN1 frameshift variant was associated with NAFLD and fibrosis, as well as with increased hepatic RIPK3 levels in familial partial lipodystrophy. CONCLUSIONS: Ripk3 deficiency restores mitochondria bioenergetics and impacts LD dynamics. RIPK3 inhibition is promising in ameliorating NAFLD.


Assuntos
Lipodistrofia Parcial Familiar , Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , Gotículas Lipídicas , Lipodistrofia Parcial Familiar/metabolismo , Lipodistrofia Parcial Familiar/patologia , Fígado/patologia , Hepatócitos/metabolismo , Metabolismo Energético , Mitocôndrias/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
4.
Front Immunol ; 13: 960226, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275699

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy derived from early T cell progenitors. Since relapsed T-ALL is associated with a poor prognosis improving initial treatment of patients is essential to avoid resistant selection of T-ALL. During initiation, development, metastasis and even in response to chemotherapy, tumor cells face strong metabolic challenges. In this study, we identify mitochondrial UnCoupling Protein 2 (UCP2) as a tricarboxylic acid (TCA) cycle metabolite transporter controlling glutamine metabolism associated with T-ALL cell proliferation. In T-ALL cell lines, we show that UCP2 expression is controlled by glutamine metabolism and is essential for their proliferation. Our data show that T-ALL cell lines differ in their substrate dependency and their energetic metabolism (glycolysis and oxidative). Thus, while UCP2 silencing decreases cell proliferation in all leukemia cells, it also alters mitochondrial respiration of T-ALL cells relying on glutamine-dependent oxidative metabolism by rewiring their cellular metabolism to glycolysis. In this context, the function of UCP2 in the metabolite export of malate enables appropriate TCA cycle to provide building blocks such as lipids for cell growth and mitochondrial respiration. Therefore, interfering with UCP2 function can be considered as an interesting strategy to decrease metabolic efficiency and proliferation rate of leukemia cells.


Assuntos
Glutamina , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Humanos , Proteína Desacopladora 2/genética , Proteína Desacopladora 2/metabolismo , Glutamina/metabolismo , Malatos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proliferação de Células , Ácidos Tricarboxílicos , Lipídeos
5.
BMC Med ; 20(1): 95, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35341481

RESUMO

BACKGROUND: Thymidine phosphorylase (TP), encoded by the TYMP gene, is a cytosolic enzyme essential for the nucleotide salvage pathway. TP catalyzes the phosphorylation of the deoxyribonucleosides, thymidine and 2'-deoxyuridine, to thymine and uracil. Biallelic TYMP variants are responsible for Mitochondrial NeuroGastroIntestinal Encephalomyopathy (MNGIE), an autosomal recessive disorder characterized in most patients by gastrointestinal and neurological symptoms, ultimately leading to death. Studies on the impact of TYMP variants in cellular systems with relevance to the organs affected in MNGIE are still scarce and the role of TP in adipose tissue remains unexplored. METHODS: Deep phenotyping was performed in three patients from two families carrying homozygous TYMP variants and presenting with lipoatrophic diabetes. The impact of the loss of TP expression was evaluated using a CRISPR-Cas9-mediated TP knockout (KO) strategy in human adipose stem cells (ASC), which can be differentiated into adipocytes in vitro. Protein expression profiles and cellular characteristics were investigated in this KO model. RESULTS: All patients had TYMP loss-of-function variants and first presented with generalized loss of adipose tissue and insulin-resistant diabetes. CRISPR-Cas9-mediated TP KO in ASC abolished adipocyte differentiation and decreased insulin response, consistent with the patients' phenotype. This KO also induced major oxidative stress, altered mitochondrial functions, and promoted cellular senescence. This translational study identifies a new role of TP by demonstrating its key regulatory functions in adipose tissue. CONCLUSIONS: The implication of TP variants in atypical forms of monogenic diabetes shows that genetic diagnosis of lipodystrophic syndromes should include TYMP analysis. The fact that TP is crucial for adipocyte differentiation and function through the control of mitochondrial homeostasis highlights the importance of mitochondria in adipose tissue biology.


Assuntos
Diabetes Mellitus Lipoatrófica , Insulinas , Adipócitos/metabolismo , Humanos , Insulinas/genética , Mutação , Timidina Fosforilase/genética , Timidina Fosforilase/metabolismo
6.
Cancers (Basel) ; 14(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35158928

RESUMO

Background In previous studies, patient-reported outcomes (PROs) have been shown to improve survival in cancer patients. The aim of the present study was to assess symptoms potentially related to adverse events experienced by cancer outpatients treated by oral anticancer agents (OAAs) using PROs. Methods Between September 2018 and May 2019, outpatients starting OAAs were included in a 12-week follow-up to assess 15 symptoms listed in the National Cancer Institute PRO Common Terminology Criteria for Adverse Events, using a 5-point scale of severity or frequency. Patients were requested to alert a referral nurse or pharmacist when they self-assessed high-level (level 3 or 4) symptoms. Results 407 questionnaires were completed by 63 patients in which 2333 symptoms were reported. Almost three-quarters (74.6%) reported at least one high-level symptom. The symptoms that were most commonly experienced were fatigue (>9 in 10 patients; 13.2% of symptoms declared), various psychological disorders (>9 in 10 patients; 28.6% of symptoms declared) and general pain (>8 in 10 patients; 9.4% of symptoms declared). Conclusion PROs are appropriate to detect potential adverse events in cancer outpatients treated by OAAs. This study is the first step for integrating the patient's perspective in a digital e-health device in routine oncology care.

7.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1866(12): 159030, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34419589

RESUMO

In the liver, contact sites between the endoplasmic reticulum (ER) and mitochondria (named MAMs) may be crucial hubs for the regulation of lipid metabolism, thus contributing to the exacerbation or prevention of fatty liver. We hypothesized that tether proteins located at MAMs could play a key role in preventing triglyceride accumulation in hepatocytes and nonalcoholic fatty liver disease (NAFLD) occurrence. To test this, we explored the role of two key partners in building MAM integrity and functionality, the glucose-regulated protein 75 (Grp75) and mitofusin 2 (Mfn2), which liver contents are altered in obesity and NAFLD. Grp75 or Mfn2 expression was either silenced using siRNA or overexpressed with adenoviruses in Huh7 cells. Silencing of Grp75 and Mfn2 resulted in decreased ER-mitochondria interactions, mitochondrial network fusion state and mitochondrial oxidative capacity, while overexpression of the two proteins induced mirror impacts on these parameters. Furthermore, Grp75 or Mfn2 silencing decreased cellular cholesterol content and enhanced triglyceride secretion in ApoB100 lipoproteins, while their overexpression led to reverse effects. Cellular phosphatidylcholine/phosphatidylethanolamine ratio was decreased only upon overexpression of the proteins, potentially contributing to altered ApoB100 assembly and secretion. Despite the opposite differences, both silencing and overexpression of Grp75 or Mfn2 induced triglyceride storage, although a fatty acid challenge was required to express the alteration upon protein silencing. Among the mechanisms potentially involved in this phenotype, ER stress was closely associated with altered triglyceride metabolism after Grp75 or Mfn2 overexpression, while blunted mitochondrial FA oxidation capacity may be the main defect causing triglyceride accumulation upon Grp75 or Mfn2 silencing. Further studies are required to decipher the link between modulation of Grp75 or Mfn2 expression, change in MAM integrity and alteration of cholesterol content of the cell. In conclusion, Grp75 or Mfn2 silencing and overexpression in Huh7 cells contribute to altering MAM integrity and cholesterol storage in opposite directions, but all promote triglyceride accumulation through distinct cellular pathways. This study also highlights that besides Mfn2, Grp75 could play a central role in hepatic lipid and cholesterol metabolism in obesity and NAFLD.


Assuntos
Apolipoproteína B-100/genética , Colesterol/metabolismo , GTP Fosfo-Hidrolases/genética , Proteínas de Choque Térmico HSP70/genética , Proteínas Mitocondriais/genética , Hepatopatia Gordurosa não Alcoólica/genética , Linhagem Celular , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , GTP Fosfo-Hidrolases/antagonistas & inibidores , Mutação com Ganho de Função/genética , Regulação da Expressão Gênica/genética , Inativação Gênica , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Mutação com Perda de Função/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/antagonistas & inibidores , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Triglicerídeos/metabolismo
8.
Biomark Res ; 9(1): 21, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33757558

RESUMO

BACKGROUND: The phase I trial of the humanized anti-CD26 monoclonal antibody YS110 for CD26-expressing tumors was conducted recently. The present study identifies a potential prognostic biomarker for CD26-targeted therapy based on the phase I data. METHODS: Box and Whisker plot analysis, Scatter plot analysis, Peason product moment correlation/Spearman's rank-difference correlation, Bar graph analysis, and Receiver Operating Characteristics (ROC) were used to examine the correlation between sCD26 titer variation with YS110 administration and tumor volume change, RECIST criteria evaluation and progression free survival (PFS). Mechanism for serum sCD26 titer variation was confirmed by in vitro experimentation. RESULTS: Serum sCD26/DPP4 titer was reduced following YS110 administration and gradually recovered until the next infusion. Serum sCD26/DPP4 titer before the next infusion was sustained at lower levels in Stable Disease (SD) cases compared to Progressive Disease cases. ROC analysis defined the cut-off level of serum sCD26/DPP4 titer variation at day 29 pre/post for the clinical outcome of SD as tumor response or PFS. In vitro experimentation confirmed that YS110 addition reduced sCD26 production from CD26-expressing tumor and non-tumor cells. CONCLUSIONS: Our study indicates that serum sCD26/DPP4 titer variation in the early phase of YS110 treatment is a predictive biomarker for evaluating therapeutic efficacy.

9.
Patient Prefer Adherence ; 14: 2263-2277, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33244223

RESUMO

INTRODUCTION: A patient education program has been developed in the field of cancer for supporting cancer patients undergoing oral anticancer therapies. Its implementation was tested in 3 different settings. The objectives of this study were to 1) identify barriers and facilitators for implementing the patient education program, 2) identify practices encouraging or hindering implementation and 3) produce recommendations for its dissemination. METHODS: Twenty semi-structured interviews were conducted with caregivers from all three establishments. RESULTS: The main factors associated with successful implementation were as follows: prescribers' representations on patient education, considered of low value; on oral anticancer therapies, considered too dangerous to be handled by the patient him/herself, the indefinite legitimacy of certain professions in charge of patient education programs; patients' engagement in their care pathway and provision of caregivers. CONCLUSION: Recommendations include developing patient education culture within the environment of the medical doctors' curriculum, to consider contextual, pre-existing cooperative units for implementing patient education, to systematically send patients to patient education programs without practicing triage. Successful implementation of patient education critically depends on the prescribing physicians' perceived value of patient education. Patient education should become mandatory, integrated as part of the cancer care pathway. Physicians lack the necessary time and/or means to assess patients' capacity for engagement, without adequate strategies for their support. Therefore, physicians should systematically refer all patients to patient education, where nurses can tailor their coaching of cancer patients. TRIAL REGISTRATION: The study protocol was approved by the IRB SUD EST I (N° EudraCT: 2016-A00113-48). All participants were given written and verbal information about the study and gave informed consent to participate.

10.
FASEB J ; 34(1): 222-236, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914644

RESUMO

Hyperosmotic conditions are associated to several pathological states. In this article, we evaluate the consequence of hyperosmotic medium on cellular energy metabolism. We demonstrate that exposure of cells to hyperosmotic conditions immediately reduces the mitochondrial oxidative phosphorylation rate. This causes an increase in glycolysis, which represses further respiration. This is known as the Warburg or Crabtree effect. In addition to aerobic glycolysis, we observed two other cellular responses that would help to preserve cellular ATP level and viability: A reduction in the cellular ATP turnover rate and a partial mitochondrial uncoupling which is expected to enhance ATP production by Krebs cycle. The latter is likely to constitute another metabolic adaptation to compensate for deficient oxidative phosphorylation that, importantly, is not dependent on glucose.


Assuntos
Neuroblastoma/metabolismo , Consumo de Oxigênio/fisiologia , Animais , Células CHO , Linhagem Celular Tumoral , Sobrevivência Celular , Cricetinae , Cricetulus , Metabolismo Energético , Células HEK293 , Humanos , Masculino , Mitocôndrias/metabolismo , Ratos , Ratos Wistar
11.
Cell Rep ; 28(9): 2306-2316.e5, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31461648

RESUMO

Colorectal cancer (CRC) is associated with metabolic and redox perturbation. The mitochondrial transporter uncoupling protein 2 (UCP2) controls cell proliferation in vitro through the modulation of cellular metabolism, but the underlying mechanism in tumors in vivo remains unexplored. Using murine intestinal cancer models and CRC patient samples, we find higher UCP2 protein levels in tumors compared to their non-tumoral counterparts. We reveal the tumor-suppressive role of UCP2 as its deletion enhances colon and small intestinal tumorigenesis in AOM/DSS-treated and ApcMin/+ mice, respectively, and correlates with poor survival in the latter model. Mechanistically, UCP2 loss increases levels of oxidized glutathione and proteins in tumors. UCP2 deficiency alters glycolytic pathways while promoting phospholipid synthesis, thereby limiting the availability of NADPH for buffering oxidative stress. We show that UCP2 loss renders colon cells more prone to malignant transformation through metabolic reprogramming and perturbation of redox homeostasis and could favor worse outcomes in CRC.


Assuntos
Carcinogênese/genética , Neoplasias Colorretais/metabolismo , Lipogênese , NADP/metabolismo , Estresse Oxidativo , Proteína Desacopladora 2/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinogênese/metabolismo , Colo/metabolismo , Colo/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Glicólise , Humanos , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Proteína Desacopladora 2/genética
12.
Cancer Chemother Pharmacol ; 82(2): 319-327, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29948022

RESUMO

PURPOSE: The aim of the OCTO clinical study was to measure patients' adherence to capecitabine-based treatment. METHODS: A cohort of ambulatory patients treated with capecitabine monotherapy for either locally advanced or metastatic, breast or colorectal cancer was monitored for 6 cycles. Adherence was assessed in all patients by self-completed questionnaires on disease, pill-count and pharmacological dosage of FBAL (metabolite of capecitabine); and in half of the cohort by electronic medication event monitoring systems (MEMS™) recording the opening times of the device. RESULTS: Forty patients were enrolled between November 2008 and September 2011 and treated by capecitabine for an average of 4.75 cycles (range 1-6). Hand-foot syndrome (HFS) was the most frequently reported toxicity (35% patients), and to a lesser extent fatigue and/or asthenia (21%), nausea and/or vomiting (13%) and diarrhea (11%). In the MEMS™ cohort, 20 patients were included. Patients' adherence was excellent with very few missing occasions (23/2272 records). Close analysis of MEMS™ data revealed unexpected medication patterns, such as patients taking extra days of medication beyond planned cycle, patients taking extra doses per day and patients missing a day of dosing and "compensating" by taking extra the following day (N = 7, 18%). A trend was found between over-adherence and high-grade toxicity (grades 3 and/or 4): OR 4.74 [0.65-45.2], p = 0.13 and higher AUC (p = 0.16). There was a trend towards increased AUC of FBAL in over-adherent patients (p = 0.16). CONCLUSION: Adherence to oral anticancer chemotherapy was found excellent in this population suggesting over-adherence to capecitabine and potential safety implications for outpatients' drugs.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Capecitabina/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Adesão à Medicação , Adulto , Idoso , Idoso de 80 Anos ou mais , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Neoplasias da Mama/psicologia , Capecitabina/efeitos adversos , Estudos de Coortes , Neoplasias Colorretais/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários
13.
Diabetologia ; 61(8): 1780-1793, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29754287

RESUMO

AIMS/HYPOTHESIS: Dietary n-3 polyunsaturated fatty acids, especially docosahexaenoic acid (DHA), are known to influence glucose homeostasis. We recently showed that Elovl2 expression in beta cells, which regulates synthesis of endogenous DHA, was associated with glucose tolerance and played a key role in insulin secretion. The present study aimed to examine the role of the very long chain fatty acid elongase 2 (ELOVL2)/DHA axis on the adverse effects of palmitate with high glucose, a condition defined as glucolipotoxicity, on beta cells. METHODS: We detected ELOVL2 in INS-1 beta cells and mouse and human islets using quantitative PCR and western blotting. Downregulation and adenoviral overexpression of Elovl2 was carried out in beta cells. Ceramide and diacylglycerol levels were determined by radio-enzymatic assay and lipidomics. Apoptosis was quantified using caspase-3 assays and poly (ADP-ribose) polymerase cleavage. Palmitate oxidation and esterification were determined by [U-14C]palmitate labelling. RESULTS: We found that glucolipotoxicity decreased ELOVL2 content in rodent and human beta cells. Downregulation of ELOVL2 drastically potentiated beta cell apoptosis induced by glucolipotoxicity, whereas adenoviral Elovl2 overexpression and supplementation with DHA partially inhibited glucolipotoxicity-induced cell death in rodent and human beta cells. Inhibition of beta cell apoptosis by the ELOVL2/DHA axis was associated with a decrease in ceramide accumulation. However, the ELOVL2/DHA axis was unable to directly alter ceramide synthesis or metabolism. By contrast, DHA increased palmitate oxidation but did not affect its esterification. Pharmacological inhibition of AMP-activated protein kinase and etomoxir, an inhibitor of carnitine palmitoyltransferase 1 (CPT1), the rate-limiting enzyme in fatty acid ß-oxidation, attenuated the protective effect of the ELOVL2/DHA axis during glucolipotoxicity. Downregulation of CPT1 also counteracted the anti-apoptotic action of the ELOVL2/DHA axis. By contrast, a mutated active form of Cpt1 inhibited glucolipotoxicity-induced beta cell apoptosis when ELOVL2 was downregulated. CONCLUSIONS/INTERPRETATION: Our results identify ELOVL2 as a critical pro-survival enzyme for preventing beta cell death and dysfunction induced by glucolipotoxicity, notably by favouring palmitate oxidation in mitochondria through a CPT1-dependent mechanism.


Assuntos
Acetiltransferases/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Animais , Apoptose/fisiologia , Elongases de Ácidos Graxos , Glucose/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Camundongos , Oxirredução , Palmitatos/metabolismo
15.
Breast Cancer Res ; 19(1): 98, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28830573

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) have to date identified 94 genetic variants (single nucleotide polymorphisms (SNPs)) associated with risk of developing breast cancer. A score based on the combined effect of the 94 risk alleles can be calculated to measure the global risk of breast cancer. We aimed to test the hypothesis that the 94-SNP-based risk score is associated with clinico-pathological characteristics, breast cancer subtypes and outcomes in early breast cancer. METHODS: A 94-SNP risk score was calculated in 8703 patients in the PHARE and SIGNAL prospective case cohorts. This score is the total number of inherited risk alleles based on 94 selected SNPs. Clinical data and outcomes were prospectively registered. Genotyping was obtained from a GWAS. RESULTS: The median 94-SNP risk score in 8703 patients with early breast cancer was 77.5 (range: 58.1-97.6). The risk score was not associated with usual prognostic and predictive factors (age; tumor, node, metastasis (TNM) status; Scarff-Bloom-Richardson grade; inflammatory features; estrogen receptor status; progesterone receptor status; human epidermal growth factor receptor 2 (HER2) status) and did not correlate with breast cancer subtypes. The 94-SNP risk score did not predict outcomes represented by overall survival or disease-free survival. CONCLUSIONS: In a prospective case cohort of 8703 patients, a risk score based on 94 SNPs was not associated with breast cancer characteristics, cancer subtypes, or patients' outcomes. If we hypothesize that prognosis and subtypes of breast cancer are determined by constitutional genetic factors, our results suggest that a score based on breast cancer risk-associated SNPs is not associated with prognosis. TRIAL REGISTRATION: PHARE cohort: NCT00381901 , Sept. 26, 2006 - SIGNAL cohort: INCa RECF1098, Jan. 28, 2009.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Estudos de Associação Genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Ensaios Clínicos Fase III como Assunto , Estudos de Coortes , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Carga Tumoral , Adulto Jovem
16.
NPJ Breast Cancer ; 3: 4, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28649644

RESUMO

Human epidermal growth factor receptor 2-positive breast cancer is a subtype of interest regarding its outcome and the impressive impact of human epidermal growth factor receptor 2 targeted therapy. Constitutional variants may be involved in the aetiology of human epidermal growth factor receptor 2-positive breast cancer, and we propose a case-case study to test the hypothesis that single nucleotide polymorphisms may be associated with human epidermal growth factor receptor 2 status. A Genome-Wide Association Study was used in a cohort of 9836 patients from the SIGNAL/PHARE study (NCT00381901-RECF1098). The main goal was to identify variants specifically related to human epidermal growth factor receptor 2-positive breast cancer. A two-staged genotyping strategy was carried out to cover as large a proportion of the genome as possible. All subjects were genotyped using the Illumina HumanCore Exome chip set. Principal Components Analysis and k-means were then used to characterize the ancestry of the participants. A random sample of subjects from the main "European" cluster was genotyped with the Omni5 chip set. These data were then used to impute missing genotypes from the remaining subjects genotyped only using the HumanCore Exome array. From the 9836 patients, a total of 8703 cases including 3230 patients with human epidermal growth factor receptor 2-positive breast cancer were analyzed. Despite having 80% power to detect an odds ratio of 1.23 in this population, no variant achieved genome-wide significance for association with the occurrence of human epidermal growth factor receptor 2-positive breast cancer vs. any other subtype of breast tumour. Our study was unable to identify constitutional polymorphisms that are strongly associated with human epidermal growth factor receptor 2-positive status among breast cancer patients.

17.
Br J Cancer ; 116(9): 1126-1134, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28291776

RESUMO

BACKGROUND: YS110 is a humanised IgG1 monoclonal antibody with high affinity to the CD26 antigen. YS110 demonstrated preclinical anti-tumour effects without significant side effects. METHODS: This FIH study was designed to determine the maximal tolerated dose (MTD) and recommended phase 2 dose (RP2D) to assess the tolerance, pharmacokinetics (PK) and pharmacodynamics profiles of YS110 and preliminary efficacy. YS110 were initially administered intravenously once every 2 weeks (Q2W) for three doses and then, based on PK data, once every week (Q1W) for five doses in patients with CD26-expressing solid tumours. RESULTS: Thirty-three patients (22 mesothelioma) received a median of 3 (range 1-30) YS110 infusions across six dose levels (0.1-6 mg kg-1). MTD was not reached and two dose-limiting toxicities (infusion hypersensitivity reactions) led to the institution of a systemic premedication. Low-grade asthenia (30.3%), hypersensitivity (27.3%), nausea (15.2%), flushing (15.2%), chills (12.1%) and pyrexia (12.1%) were reported as ADRs. Pharmacokinetic parameters (AUC and Cmax) increased in proportion with the dose. sCD26/DPPIV assays indicated CD26 modulation. Prolonged stable diseases were observed in 13 out of 26 evaluable patients. CONCLUSIONS: YS110 is well tolerated up to 6 mg kg-1 Q1W, which has been defined as the RP2D, with encouraging prolonged disease stabilisations observed in a number of patients with advanced/refractory mesothelioma.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Dipeptidil Peptidase 4/sangue , Imunoglobulina G/administração & dosagem , Mesotelioma/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacocinética , Dipeptidil Peptidase 4/efeitos dos fármacos , Dipeptidil Peptidase 4/imunologia , Relação Dose-Resposta a Droga , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/sangue , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imunoglobulina G/imunologia , Masculino , Dose Máxima Tolerável , Mesotelioma/sangue , Mesotelioma/imunologia , Mesotelioma/patologia , Pessoa de Meia-Idade
18.
Bull Cancer ; 104(6): 538-551, 2017 Jun.
Artigo em Francês | MEDLINE | ID: mdl-28237353

RESUMO

INTRODUCTION: In the context of health expenses control, reimbursement of high-cost medicines with a 'minor' or 'nonexistent' improvement in actual health benefit evaluated by the Haute Autorité de santé is revised by the decree of March 24, 2016 related to the procedure and terms of registration of high-cost pharmaceutical drugs. This study aims to set up the economic impact of this measure. METHOD: A six months retrospective study was conducted within a French university hospital from July 1, 2015 to December 31, 2015. For each injectable high-cost anticancer drug prescribed to a patient with cancer, the therapeutic indication, its status in relation to the marketing authorization and the associated improvement in actual health benefit were examined. The total costs of these treatments, the cost per type of indication and, in the case of marketing authorization indications, the cost per improvement in actual health benefit were evaluated considering that all drugs affected by the decree would be struck off. RESULTS: Over six months, 4416 high-cost injectable anticancer drugs were prescribed for a total cost of 4.2 million euros. The costs of drugs with a minor or nonexistent improvement in actual benefit and which comparator is not onerous amount 557,564 euros. DISCUSSION: The reform of modalities of inscription on the list of onerous drugs represents a significant additional cost for health institutions (1.1 million euros for our hospital) and raises the question of the accessibility to these treatments for cancer patients.


Assuntos
Antineoplásicos/economia , Análise Custo-Benefício , Legislação de Medicamentos/economia , Neoplasias/tratamento farmacológico , Administração Cutânea , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/economia , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/economia , Antineoplásicos/administração & dosagem , Custos de Medicamentos , França , Hospitais Universitários/economia , Humanos , Injeções Intravenosas , Melhoria de Qualidade , Estudos Retrospectivos , Fatores de Tempo
19.
Oncotarget ; 7(47): 77358-77364, 2016 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-27764800

RESUMO

Genetic polymorphisms are associated with breast cancer risk. Clinical and epidemiological observations suggest that clinical characteristics of breast cancer, such as estrogen receptor or HER2 status, are also influenced by hereditary factors. To identify genetic variants associated with pathological characteristics of breast cancer patients, a Genome Wide Association Study was performed in a cohort of 9365 women from the French nationwide SIGNAL/PHARE studies (NCT00381901/RECF1098). Strong association between the FGFR2 locus and ER status of breast cancer patients was observed (ER-positive n=6211, ER-negative n=2516; rs3135718 OR=1.34 p=5.46×10-12). This association was limited to patients with HER2-negative tumors (ER-positive n=4267, ER-negative n=1185; rs3135724 OR=1.85 p=1.16×10-11). The FGFR2 locus is known to be associated with breast cancer risk. This study provides sound evidence for an association between variants in the FGFR2 locus and ER status among breast cancer patients, particularly among patients with HER2-negative disease. This refinement of the association between FGFR2 variants and ER-status to HER2-negative disease provides novel insight to potential biological and clinical influence of genetic polymorphisms on breast tumors.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/genética , Estudo de Associação Genômica Ampla , Receptor ErbB-2/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Ensaios Clínicos Fase III como Assunto , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Ensaios Clínicos Controlados Aleatórios como Assunto , Receptores de Estrogênio/genética
20.
Am J Physiol Endocrinol Metab ; 311(3): E649-60, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27507552

RESUMO

Impaired skeletal muscle mitochondrial fatty acid oxidation (mFAO) has been implicated in the etiology of insulin resistance. Carnitine palmitoyltransferase-1 (CPT1) is a key regulatory enzyme of mFAO whose activity is inhibited by malonyl-CoA, a lipogenic intermediate. Whereas increasing CPT1 activity in vitro has been shown to exert a protective effect against lipid-induced insulin resistance in skeletal muscle cells, only a few studies have addressed this issue in vivo. We thus examined whether a direct modulation of muscle CPT1/malonyl-CoA partnership is detrimental or beneficial for insulin sensitivity in the context of diet-induced obesity. By using a Cre-LoxP recombination approach, we generated mice with skeletal muscle-specific and inducible expression of a mutated CPT1 form (CPT1mt) that is active but insensitive to malonyl-CoA inhibition. When fed control chow, homozygous CPT1mt transgenic (dbTg) mice exhibited decreased CPT1 sensitivity to malonyl-CoA inhibition in isolated muscle mitochondria, which was sufficient to substantially increase ex vivo muscle mFAO capacity and whole body fatty acid utilization in vivo. Moreover, dbTg mice were less prone to high-fat/high-sucrose (HFHS) diet-induced insulin resistance and muscle lipotoxicity despite similar body weight gain, adiposity, and muscle malonyl-CoA content. Interestingly, these CPT1mt-protective effects in dbTg-HFHS mice were associated with preserved muscle insulin signaling, increased muscle glycogen content, and upregulation of key genes involved in muscle glucose metabolism. These beneficial effects of muscle CPT1mt expression suggest that a direct modulation of the malonyl-CoA/CPT1 partnership in skeletal muscle could represent a potential strategy to prevent obesity-induced insulin resistance.


Assuntos
Carnitina O-Palmitoiltransferase/biossíntese , Dieta Hiperlipídica/efeitos adversos , Sacarose Alimentar/efeitos adversos , Resistência à Insulina , Malonil Coenzima A/metabolismo , Músculo Esquelético/metabolismo , Animais , Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Carnitina O-Palmitoiltransferase/genética , Metabolismo Energético/efeitos dos fármacos , Glucose/metabolismo , Masculino , Malonil Coenzima A/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/metabolismo , Mutação/genética , Obesidade/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
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