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Eric Jourdan

Publications and source records attributed to Eric Jourdan.

At least 19 recordsLinked to original sources
PubMed2006

CD200 is a new prognostic factor in multiple myeloma.

Using Affymetrix microarrays, we identified the expression of the CD200 gene in multiple myeloma cells (MMCs) of 112 patients with newly diagnosed multiple myeloma (MM). The CD200 gene was either absent or present (Affymetrix call) in 22% and 78% of MMCs, respectively. The CD200 gene is not expressed in cells of the patients' bone marrow (BM). CD200 is a membrane glycoprotein that imparts an immunoregulatory signal through CD200R, leading to the suppression of T-cell-mediated immune responses. Patients with CD200(absent) MMCs have an increased event-free survival (EFS; 24 months) compared with patients with CD200(present) MMCs (14 months), after high-dose therapy and stem cell transplantation. In a Cox proportional-hazard model, the absence or presence of CD200 expression in MMCs is predictive for EFS for patients independently of ISS stage or beta2M serum levels. Thus, CD200 is an independent prognosis factor for patients with MM that could represent a new therapeutic target in MM.

Antigens, CD↗
PubMed2005

Early allogeneic stem-cell transplantation for young adults with acute myeloblastic leukemia in first complete remission: an intent-to-treat long-term analysis of the BGMT experience.

PURPOSE: We analyzed the impact of allogeneic stem-cell transplantation (alloSCT) as an early consolidation for young patients with acute myeloblastic leukemia in first complete remission (CR1) through four successive protocols. PATIENTS AND METHODS: Of the 472 patients who achieved CR1, 182 (38%) had an HLA-identical sibling (donor group), and alloSCT was performed in 171 patients (94%). Of the 290 patients without donor (no-donor group), 62% received an autologous SCT. RESULTS: In an intent-to-treat analysis based on donor availability, the overall 10-year survival probability was 51% v 43% (P = .11) for the donor and no-donor groups, respectively. A Cox analysis determined that four factors had independent prognostic significance for survival (initial WBC count, French-American-British subtypes, cytogenetic risk, and number of induction courses). This permitted constitution of a simple index that reclassified 21% of the patients compared with usual cytogenetic classification and identified three subpopulations with different outcome and different impact of alloSCT. CONCLUSION: AlloSCT was associated with a survival advantage for an intermediate-risk group. In other groups, numbers are limited for definitive conclusion. However, early performed alloSCT does not seem to be the optimal treatment of high-risk patients or offer any advantage over intensive chemotherapy in low-risk patients.

Acute Disease↗
PubMed2005

Expression of EGF-family receptors and amphiregulin in multiple myeloma. Amphiregulin is a growth factor for myeloma cells.

A hallmark of plasma cells is the expression of syndecan-1, which has major functions in epithelial cells, in particular as the coreceptor of heparin-binding growth factors. We previously found that heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a growth factor for malignant plasma cells. As amphiregulin (AREG) is another heparin-binding factor of the EGF family, we investigated its role in multiple myeloma (MM). Using Affymetrix DNA microarrays, we show here that the AREG gene was expressed by purified primary myeloma cells from 65 patients and that the expression was higher than in normal bone marrow (BM) plasma cells or plasmablastic cells. AREG stimulated IL-6 production and growth of BM stromal cells. Using real-time reverse transcriptase-polymerase chain reaction, we found that MM cells expressed ErbB receptors and that AREG promoted their growth. Furthermore, PD169540 (a pan-ErbB inhibitor) and IRESSA (an ErbB1-specific inhibitor) induced apoptosis of primary myeloma cells from 10/14 and 4/14 patients, respectively, and there was a synergistic effect with dexamethasone. Altogether, our data provide strong evidence that AREG plays an important role in the biology of MM and emphasize the advantages of using ErbB inhibitors, which might target myeloma cells as well as the tumor environment.

Amphiregulin↗
PubMed2005

Essential role for the p110delta isoform in phosphoinositide 3-kinase activation and cell proliferation in acute myeloid leukemia.

The phosphoinositide 3-kinase (PI3K)/Akt signaling pathway has been shown to be frequently activated in blast cells from patients with acute myeloid leukemia (AML) and to contribute to survival and proliferation of these cells. Of the 8 distinct mammalian isoforms of PI3K, it is the class I PI3Ks (p110alpha, p110beta, p110gamma, and p110delta) that are responsible for Akt activation. It is not known which PI3K isoform is critical in AML. Here we show that the p110delta isoform of PI3K is consistently expressed at a high level in blast cells from AML, in contrast to the other class I isoforms, the expression of which was very variable among patients. IC87114, a p110delta-selective inhibitor, suppressed both constitutive and Flt-3-stimulated Akt activation in blasts to the same extent as Ly294002, an inhibitor of all PI3K isoforms. Moreover, IC87114 inhibited AML cell proliferation without affecting the proliferation of normal hematopoietic progenitor cells. These observations identify p110delta as a potential therapeutic target in AML.

Acute Disease↗
PubMed2005

The level of TACI gene expression in myeloma cells is associated with a signature of microenvironment dependence versus a plasmablastic signature.

B-cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) have been shown to promote multiple myeloma (MM) cell growth. We show that the main site of production for BAFF and APRIL is the bone marrow (BM) environment, and that production is mainly by monocytes and neutrophils. In addition, osteoclasts produce very high levels of APRIL, unlike BM stromal cells. Myeloma cells (MMCs) express TACI (transmembrane activator and calcium modulator and cyclophilin ligand interactor), the receptor of BAFF/APRIL, at varying levels. TACI expression is a good indicator of a BAFF-binding receptor. Expression data of purified MMCs from 65 newly diagnosed patients have been generated using Affymetrix microarrays and were analyzed by supervised clustering of groups with higher (TACI(hi)) versus lower (TACI(lo)) TACI expression levels. Patients in the TACI(lo) group had clinical parameters associated with bad prognosis. A set of 659 genes was differentially expressed between TACI(hi) and TACI(lo) MMCs. This set makes it possible to efficiently classify TACI(hi) and TACI(lo) MMCs in an independent cohort of 40 patients. TACI(hi) MMCs displayed a mature plasma cell gene signature, indicating dependence on the BM environment. In contrast, the TACI(lo) group had a gene signature of plasmablasts, suggesting an attenuated dependence on the BM environment. Taken together, our findings suggest using gene expression profiling to identify the group of patients who might benefit most from treatment with BAFF/APRIL inhibitors.

B-Cell Activating Factor↗
PubMed2005

One versus two high-dose cytarabine-based consolidation before autologous stem cell transplantation for young acute myeloblastic leukaemia patients in first complete remission.

We report on a randomized trial aimed to determine the impact of a second consolidative high-dose cytarabine-based chemotherapy (HiDAC) in patients with acute myeloid leukaemia prior to an autologous stem cell transplantation (ASCT). Patients aged 18-60 years, in complete remission (CR) received a first consolidation with daunorubicin and cytarabine at reduced dose. Patients not allocated to allogeneic transplantation received one course of HiDAC and then were randomized to receive an ASCT immediately (HiDAC 1 group) or after one more course of HiDAC (HiDAC 2 group). Out of the 437 initial patients, 351 achieved CR (80%), of those 277 (79%) were eligible for first HiDAC, and 128 (36%) were randomized (HiDAC 1:65, HiDAC 2:63). Overall survival, leukaemia-free survival and cumulative incidence of relapse and non-relapse deaths were 41% and 53% (P = 0.14), 39% and 48% (P = 0.12), 57% and 47% (P = 0.11), 8% and 8% (P = 0.95) for HiDAC 1 and HiDAC 2 groups, respectively. Further studies are warranted with a larger number of patients to test the place of a second course of HiDAC in this setting.

Adolescent↗
PubMed2004

Zinc-metallothionein genoprotective effect is independent of the glutathione depletion in HaCaT keratinocytes after solar light irradiation.

UV radiations are the major environmental factors that induce DNA damage of skin cells either by direct absorption (UVB), or after inducing an oxidative stress (UVA and UVB). Cells maintain a reducing intracellular environment to avoid genomic damage. MTs have been expected not only to control metal homeostasis but also counteract the glutathione (GSH) depletion induced by oxidative stress because of their high thiol content. Induction and redistribution of MTs in cultured human keratinocytes (HaCaT) in response to SSL, is an important cellular defense mechanism against DNA damage. Reduced glutathione (GSH) is another way of cellular protection against UV-induced oxidative stress. This study which extend our previous finding focused on the relation between intracellular GSH and Zn genoprotective effects after solar irradiation. HaCaT cells, depleted or not in GSH by a chemical treatment were used to compare MTs induction by Northern blot, expression by Western blot and localization using immunocytochemistry. Zn genoprotection experiments after SSL irradiation was carried out by the comet assay. We demonstrated that in absence of GSH, Zn-MTs could protect DNA after SSL irradiation and that GSH depletion has no effect on MTs induction and localization. Nuclear Zn-MTs could be responsible for this observed genoprotection in GSH depleted cells. So the GSH/Zn and the MT/Zn systems could be two independent but interacting mechanisms of cellular protection against SSL injury.

Cell Line↗
PubMed2004

Immobilized DNA aptamers as target-specific chiral stationary phases for resolution of nucleoside and amino acid derivative enantiomers.

Recently, we described the use of a DNA aptamer as a new target-specific chiral stationary phase (CSP) for the separation of oligopeptide enantiomers (Michaud, M.; Jourdan, E.; Villet, A.; Ravel, A.; Grosset, C.; Peyrin, E. J. Am. Chem. Soc. 2003, 125, 8672). However, from a practical point of view, it was fundamental to extend the applicability of such target-specific aptamer CSP to the resolution of small (bioactive) molecule enantiomers. In this paper, immobilized DNA aptamers specifically selected against D-adenosine and L-tyrosinamide were used to resolve the enantiomers by HPLC, using microbore columns. At 20 degrees C, the adenosine enantioseparation was similar to that classically reported with imprinted CSPs (approximately 3.5) while a very high enantioselectivity was observed for the tyrosinamide enantiomers (the nontarget enantiomer was essentially nonretained on the CSP). The influence of temperature on solute binding and chiral discrimination was analyzed. The binding enthalpic contributions were determined from linear van't Hoff plots. Very large DeltaH values were obtained for the target enantiomers (-71.4 +/- 0.7 kJ/mol for D-adenosine and -139.4 +/- 2.0 kJ/mol for L-tyrosinamide). Such values were consistent with the formation of a tight complex between these analytes and the aptamer CSPs. This work demonstrates that target-specific aptamer CSPs constitute a powerful tool for the resolution of small (bioactive) molecule enantiomers.

Adenosine↗
PubMed2004

Imatinib and plasmacytoid dendritic cell function in patients with chronic myeloid leukemia.

Plasmacytoid dendritic cells (PDCs) are crucial effectors in innate immunity. In this study, we show that imatinib, a potent inhibitor of BCR/ABL tyrosine kinase activity, in the presence of Flt3-Ligand, could induce CD34+ progenitors from chronic myeloid leukemia (CML) to give rise in vitro to typical BDCA-2+ type I interferon-producing PDCs. The effect of imatinib on PDC generation was related to up-regulation of Flt3 on leukemic CD34+ progenitors. Moreover, patients with chronic myeloid leukemia (CML) who were in complete cytogenetic or molecular response after imatinib treatment restored their blood PDCs both quantitatively and functionally comparable to healthy donors, in contrast to patients not responding to imatinib, further confirming that disease response to imatinib is accompanied by restoration of PDC function in vivo. These findings provide evidence that response to imatinib is capable to restore some DC-related immune functions in CML that might be beneficial for long-term disease control.

Antineoplastic Agents↗
PubMed2003

Comparison of murine leukemia virus, human immunodeficiency virus, and adeno-associated virus vectors for gene transfer in multiple myeloma: lentiviral vectors demonstrate a striking capacity to transduce low-proliferating primary tumor cells.

Genetic modification of primary tumor cells by gene transfer is of major interest to study the role of specific genes in the biology of a given malignancy and to modify tumor cells for therapeutic use. Multiple myeloma (MM) is a low-proliferating cancer, with often less than 1% of the cells in the S phase of the cell cycle. As primary myeloma cells are notoriously difficult to transduce, we conducted a comparison of various viral vectors, known to integrate the transgene of interest into the target genome, for their ability to stably promote the expression of an enhanced green fluorescent protein (EGFP) transgene. We compared three murine leukemia virus-based vectors, differing only in their viral envelope, a human immunodeficiency virus (HIV)-based vector pseudotyped with the vesicular stomatitis virus glycoprotein (VSV-G), and an adeno-associated virus type 2 vector. Transduction characteristics of these vectors were evaluated in human myeloma cell lines and in primary myeloma cells. Unequivocally, we observed that the VSV-G/HIV vector was the most efficient vector for transducing the cell lines and the only one able to transduce primary myeloma cells reproducibly. The mean percentage of transduced primary myeloma cells was 43.6% (range, 16.3-77.6%), with one round of infection at a low multiplicity of infection, including MM cell samples with less than 1% of cells in the S phase. A quantitative polymerase chain reaction assay demonstrated that this more efficient EGFP expression was associated with a higher GFP copy number in the targeted cell. We propose that lentiviral vectors should be used for transduction of nonproliferating primary tumor cells such as myeloma cells.

Adenoviridae↗
PubMed2003

BAFF and APRIL protect myeloma cells from apoptosis induced by interleukin 6 deprivation and dexamethasone.

Identification of growth factors in neoplasias may be a target for future therapies by blocking either growth factor receptor interaction or the induced pathway. Using gene expression profiling, we identified overexpression of 2 receptors for a proliferation-inducing ligand (APRIL) and B-cell activating factor (BAFF) in malignant plasma cells compared with normal plasma cells. APRIL and BAFF are involved in a variety of tumor and autoimmune diseases, including B-cell malignancies. We confirmed the expression of BAFF and APRIL receptors (B-cell maturation antigen [BCMA], transmembrane activator and calcium modulator and cyclophilin ligand interactor [TACI], and BAFF-R) in a majority of 13 myeloma cell lines and in the purified primary myeloma cells of 11 patients. APRIL and BAFF were potent survival factors for exogenous cytokine-dependent myeloma cell lines and were autocrine growth factors for the RPMI8226 and L363 autonomously growing cell lines. These factors activated nuclear factor (NF)-kappaB, phosphatidylinositol-3 (PI-3) kinase/AKT, and mitogen-activated protein kinase (MAPK) kinase pathways and induced a strong up-regulation of the Mcl-1 and Bcl-2 antiapoptotic proteins in myeloma cells. BAFF or APRIL was also involved in the survival of primary myeloma cells cultured with their bone-marrow environment, and protected them from dexamethasone (DEX)-induced apoptosis. Finally, the serum levels of BAFF and APRIL were increased about 5-fold in patients with multiple myeloma (MM) as compared with healthy donors. Altogether, these data suggest that APRIL/BAFF inhibitors may be of clinical value in MM.

Apoptosis↗
PubMed2003

Efficacy and safety of rasburicase (recombinant urate oxidase) for the prevention and treatment of hyperuricemia during induction chemotherapy of aggressive non-Hodgkin's lymphoma: results of the GRAAL1 (Groupe d'Etude des Lymphomes de l'Adulte Trial on Rasburicase Activity in Adult Lymphoma) study.

PURPOSE: Hyperuricemia and tumor lysis syndrome are well-known complications during induction treatment of aggressive non-Hodgkin's lymphomas (NHLs). Usual prophylaxis and treatment of hyperuricemia consist of hydration, alkalinization, and administration of allopurinol. This study was designed to evaluate the efficacy and the safety of rasburicase (recombinant urate oxidase) in adult patients with aggressive NHL during their first cycle of chemotherapy. PATIENTS AND METHODS: A total of 100 patients from Groupe d'Etude des Lymphomes de l'Adulte centers, with diffuse large B-cell lymphoma (n = 79); anaplastic large-cell lymphoma (n = 6); peripheral T-cell lymphoma (n = 8); transformation of indolent lymphoma (n = 5); Burkitt's lymphoma (n = 1); and lymphoblastic lymphoma (n = 1) were enrolled from May 2001 to June 2002. Before chemotherapy, 66% of patients had elevated lactate dehydrogenase (LDH), including 28% with LDH above 1,000 U/mL. Eleven percent of patients were hyperuricemic (uric acid [UA] > 450 mmol/L or > 7.56 mg/dL). Rasburicase 0.20 mg/kg/d intravenously for 3 to 7 days was started the day before or at day 1 of chemotherapy. UA levels were measured 4 hours after rasburicase injection, then daily during treatment. RESULTS: All patients responded to rasburicase, as defined by normalization of UA levels maintained during chemotherapy. The control of UA was obtained within 4 hours after the first injection of the drug. Creatinine levels and other metabolites were also controlled with the administration of rasburicase. No patient exhibited increased creatinine levels or required dialysis during chemotherapy. CONCLUSION: Rasburicase is the treatment of choice to control UA and prevent tumor lysis syndrome in adult patients with aggressive NHL.

Adult↗
PubMed2003

An inhibitor of the EGF receptor family blocks myeloma cell growth factor activity of HB-EGF and potentiates dexamethasone or anti-IL-6 antibody-induced apoptosis.

We previously found that some myeloma cell lines express the heparin-binding epidermal growth factor-like growth factor (HB-EGF) gene. As the proteoglycan syndecan-1 is an HB-EGF coreceptor as well as a hallmark of plasma cell differentiation and a marker of myeloma cells, we studied the role of HB-EGF on myeloma cell growth. The HB-EGF gene was expressed by bone marrow mononuclear cells in 8 of 8 patients with myeloma, particularly by monocytes and stromal cells, but not by purified primary myeloma cells. Six of 9 myeloma cell lines and 9 of 9 purified primary myeloma cells expressed ErbB1 or ErbB4 genes coding for HB-EGF receptor. In the presence of a low interleukin-6 (IL-6) concentration, HB-EGF stimulated the proliferation of the 6 ErbB1+ or ErbB4+ cell lines, through the phosphatidylinositol 3-kinase/AKT (PI-3K/AKT) pathway. A pan-ErbB inhibitor blocked the myeloma cell growth factor activity and the signaling induced by HB-EGF. This inhibitor induced apoptosis of patients'myeloma cells cultured with their tumor environment. It also increased patients' myeloma cell apoptosis induced by an anti-IL-6 antibody or dexamethasone. The ErbB inhibitor had no effect on the interaction between multiple myeloma cells and stromal cells. It was not toxic for nonmyeloma cells present in patients' bone marrow cultures or for the growth of hematopoietic progenitors. Altogether, these data identify ErbB receptors as putative therapeutic targets in multiple myeloma.

Antineoplastic Agents, Hormonal↗
PubMed2003

Role of the vancomycin-ristocetin heterodimerization on the enantioselectivity of D,L-tryptophan and D,L-dansyl tryptophan.

In this paper, a chromatographic system using immobilized ristocetin as chiral stationary phase and vancomycin as chiral mobile phase additive (CMPA) was described in order to investigate the role of the glycopeptide heterodimerization on the retention and enantioselectivity of D,L-tryptophan and D,L-dansyl tryptophan. A simplified interaction model was derived considering the formation of heterodimers between immobilized ristocetin and vancomycin. This theoretical approach was convenient to describe adequately the retention behavior. When the CMPA concentration increased, the solute retention factor increased for all the solute enantiomers studied indicating that the vancomycin adsorbed on the immobilized ristocetin played a preponderant role in the retention. The D,L-tryptophan enantioselectivity on the dynamically modified stationary phase was improved by a factor of 1.3, probably due to a glycopeptide conformational change upon heterodimerization. On the other hand, a decrease in the chiral discrimination of D,L-dansyl tryptophan was observed. Such a behavior seems to result from the antagonist enantioselective properties of the two glycopeptides for the dansyl amino acids.

Chromatography, High Pressure Liquid↗
PubMed2003

A DNA aptamer as a new target-specific chiral selector for HPLC.

In this paper, a DNA aptamer, known to bind stereospecifically the D-enantiomer of an oligopeptide, i.e., arginine-vasopressin, was immobilized on a chromatographic support. The influence of various parameters (such as column temperature, eluent pH, and salt concentration) on the L- and D-peptide retention was investigated in order to provide information about the binding mechanism and then to define the utilization conditions of the aptamer column. The results suggest that dehydration at the binding interface, charge-charge interactions, and adaptive conformational transitions contribute to the specific D-peptide-aptamer complex formation. A very significant enantioselectivity was obtained in the optimal binding conditions, the D-peptide being strongly retained by the column while the L-peptide eluted in the void volume. A rapid baseline separation of peptide enantiomers was also achieved by modulating the elution conditions. Furthermore, it was established that the aptamer column was stable during an extended period of time. This work indicates that DNA aptamers, specifically selected against an enantiomer, could soon become very attractive as new target-specific chiral selectors for HPLC.

Arginine Vasopressin↗
PubMed2003

Study of tryptophan enantiomer binding to a teicoplanin-based stationary phase using the perturbation technique. Investigation of the role of sodium perchlorate in solute retention and enantioselectivity.

The retention of D,L-tryptophan enantiomers on an immobilized teicoplanin column was investigated in relation to the mobile phase sodium perchlorate concentration using the perturbation method to determine the solute distribution isotherms. From the experimental data, it appeared that the bi-Langmuir model was able to describe D- and L-enantiomer retention on the immobilized selector over the salt concentration range. An increase in the apparent enantioselectivity with an increase in sodium perchlorate concentration was observed. The chiral recognition enhancement was governed by (i) an increase in the difference of the adsorption constants for binding to the high-affinity site (aglycone pocket) between the two enantiomers and (ii) enhancement of the number of aglycone chiral regions interacting with D-tryptophan. It is suggested that an ion-pair formation mechanism between perchlorate and solute and/or selector is responsible for this behavior. In addition, this work shows that additional secondary sites on the teicoplanin surface are involved in the apparent enantioselectivity at low sodium perchlorate concentrations.

Perchlorates↗
PubMed2003

Survival and proliferation factors of normal and malignant plasma cells.

Since the first identification of interleukin (IL)-6 as a myeloma cell growth factor by Dr. Kawano's and Dr. Klein's groups 14 years ago, numerous studies have emphasized its major roles in the emergence of malignant plasma cells in vivo and in the generation of normal plasma cells. Four transcription factors control B-cell differentiation into plasma cells. The B-cell transcription factor pax-5 is mainly responsible for a B-cell phenotype, and bcl-6 represses the plasma cell transcription factor blimp-1 and plasma cell differentiation. bcl-6 expression is triggered by CD40 and IL-4 activation. A lack of CD40 and IL-4 activation yields a down-regulation of bcl-6 expression, and IL-6 stimulation yields an up-regulation of blimp-1, mainly through STAT3 activation. Blimp-1 further down-regulates bcl-6 and pax-5 expression and makes plasma cell differentiation possible. IL-6 as well as IL-10 up-regulate XBP-1. XBP-1 is another transcription factor that is involved in plasma cell differentiation and whose gene expression is shut down by pax-5. The plasma cell transcription factors blimp-1 and XBP-1 are up-regulated, and the B-cell transcription factors bcl-6 and pax-5 are down-regulated, in malignant cells compared to B-cells. Apart from the recent identification of these 4 transcription factors, the factors involved in normal plasma cell generation are mostly unknown. Regarding malignant plasma cells, 3 categories of growth factors have been identified: (1) the IL-6 family cytokines, IL-10, and interferon alpha that activate the Janus kinase-signal transducer and activator of transcription (JAK/STAT) and mitogen-activated protein (MAP) kinase pathways; (2) growth factors activating the phosphatidylinositol (PI)-3 kinase/AKT and MAP kinase pathways, unlike the JAK/STAT pathway (insulin-like growth factor 1, hepatocyte growth factor, and members of the epidermal growth factor family able to bind syndecan-1 proteoglycan); and (3) B-cell-activating factor (BAFF) or proliferation-inducing ligand (APRIL) that activate the nuclear factor KB and PI-3 kinase/AKT pathways. BAFF and APRIL bind to BAFF receptor and TACI and are major B-cell survival factors. Recent data indicate that these various growth factors may cooperate to provide optimum signaling because they are localized together and with cytoplasmic transduction elements in caveolinlinked membrane caveolae. The identification of these myeloma cell growth factors and of the associated transduction pathways should provide novel therapeutic targets in multiple myeloma.

B-Cell Activating Factor↗