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Laurent Degos

Publications and source records attributed to Laurent Degos.

17 recordsLinked to original sources
PubMed2006

Is cytarabine useful in the treatment of acute promyelocytic leukemia? Results of a randomized trial from the European Acute Promyelocytic Leukemia Group.

PURPOSE: Several phase II studies have suggested that cytarabine (AraC) was not required in the treatment of newly diagnosed acute promyelocytic leukemia (APL) patients receiving all-trans-retinoic acid (ATRA), an anthracycline, and maintenance therapy, and we aimed at confirming this finding in a randomized trial. PATIENTS AND METHODS: Newly diagnosed APL patients younger than age 60 years with a WBC count of less than 10,000/microL were randomly assigned to receive either ATRA combined with and followed by three daunorubicin (DNR) plus AraC courses and a 2-year maintenance regimen (AraC group) or the same treatment but without AraC (no AraC group). Patients older than age 60 years and patients with initial WBC count of more than 10,000/microL were not randomly assigned but received risk-adapted treatment, with higher dose of AraC and CNS prophylaxis in patients with WBC counts more than 10,000/microL. RESULTS: Overall, 328 (96.5%) of 340 patients achieved complete remission (CR). In the AraC and the no AraC groups, the CR rates were 99% and 94% (P = .12), the 2-year cumulative incidence of relapse (CIR) rates were 4.7% and 15.9% (P = .011), the event-free survival (EFS) rates were 93.3% and 77.2% (P = .0021), and survival rates were 97.9% and 89.6% (P = .0066), respectively. In patients younger than age 60 years with WBC counts more than 10,000/microL, the CR, 2-year CIR, EFS, and survival rates were 97.3%, 2.9%, 89%, and 91.9%, respectively. CONCLUSION: These results support a role for AraC in addition to ATRA and anthracyclines in the treatment of newly diagnosed APL, at least using DNR at the cumulative dose we used and with the consolidation and maintenance regimens we used.

Adult↗
PubMed2005

Molecular target-based treatment of human cancer: summary of the 10th international conference on differentiation therapy.

The 10th International Conference on Differentiation Therapy was held between April 29 and May 3, 2004, in Shanghai, China. In the tradition of previous conferences from this series, which have been held biannually since the first meeting organized 20 years ago by Samuel Waxman and Giovanni Rossi in Sardinia, the organizers of the 10th International Conference on Differentiation Therapy aimed to gather basic and clinical cancer investigators in a setting of plenary sessions, workshops, and poster presentations to maximize the effective exchange of information and foster the establishment of collaborative interactions. Approximately 300 scientists attended the meeting with a mission to discuss targeted approaches to cancer treatment, which stem from our understanding of basic biological processes and the mechanisms of their deregulation during tumorigenesis.

Apoptosis↗
PubMed2005

Valproic acid and all-trans retinoic acid for the treatment of elderly patients with acute myeloid leukemia.

Valproic acid (VPA) has been demonstrated to be able to inhibit histone deacetylase activity and to synergize with all-trans retinoic acid (ATRA) in inducing the differentiation of acute myeloid leukemia (AML) cells. A pilot study of the VPA/ATRA combination was performed in 11 elderly patients with de novo AML (median age, 82 years). Complete marrow response was observed in 3 patients, including 1 complete remission. Two additional patients had hematologic improvement.

Aged↗
PubMed2004

Randomized comparison of double induction and timed-sequential induction to a "3 + 7" induction in adults with AML: long-term analysis of the Acute Leukemia French Association (ALFA) 9000 study.

Between 1990 and 1996, we conducted a randomized trial in adults with newly diagnosed acute myeloid leukemia (AML) in order to compare relapse-free interval (RFI) after double induction (arm B), timed-sequential induction (arm C), or control "3 + 7" induction (arm A). Patients achieving complete remission (CR) after induction +/- salvage received the same consolidation chemotherapy, which included a dosage stratification according to patient's age (younger or older than 50 years). This long-term analysis was performed in 592 patients (arm A/B/C, 197/198/197 patients). Overall CR rate was 76% without differences between the 3 arms, even if a salvage course was less frequently needed in arm B. Treatment-related mortality, either during the induction or the postremission phase, was not significantly higher in arms B and C than in arm A. Among the 449 CR patients, 250 relapsed (arm A/B/C, 90/87/73 patients) without significant differences in RFI in arms B and C versus arm A (P = .39 and .15, by the Gray test). However, when analyzing the 345 patients younger than 50, RFI was significantly improved in younger patients receiving timed-sequential induction (P = .038 by the Gray test), while not in those receiving double induction. Event-free survival and overall survival were similar in the 3 randomization arms.

Adolescent↗
PubMed2004

Phase II trial of arsenic trioxide and alpha interferon in patients with relapsed/refractory adult T-cell leukemia/lymphoma.

Human T-cell lymphotropic virus type 1 associated adult T-cell leukemia/lymphoma carries a very poor prognosis due to its intrinsic resistance to chemotherapy. Although zidovudine (AZT) and alpha-interferon (IFN) yield some responses and improve ATL prognosis, alternative therapies are needed. Arsenic trioxide (As) dramatically synergizes with IFN to induce growth arrest and apoptosis of ATL leukemia cells in vitro. These results prompted us to initiate a phase II trial of As/IFN combination in seven patients with relapsed/refractory ATL (four acute and three lymphoma). Four patients exhibited a clear initial response (one complete remission and three partial remissions). Yet, the treatment was discontinued after a median of 22 days because of toxicity (three patients) or subsequent progression (four patients). Six patients eventually died from progressive disease (five patients) or infection (one patient), but the remaining patient is still alive and disease free at 32 months. Pharmacokinetic studies showed that maximum arsenic blood levels (median 0.46 microM) were slowly achieved (8-15 days). In conclusion, arsenic/IFN treatment is feasible and exhibits an anti-leukemia effect in very poor prognosis ATL patients despite a significant toxicity. Future studies should assess the best timing for arsenic therapy: frontline with IFN/AZT or as maintenance after induction.

Adult↗
PubMed2003

Relationship between elevated levels of the alpha 1 acid glycoprotein in chronic myelogenous leukemia in blast crisis and pharmacological resistance to imatinib (Gleevec) in vitro and in vivo.

The Abl tyrosine kinase inhibitor imatinb is becoming a standard for the treatment of chronic myelogenous leukemia (CML). However, Bcr-Abl gene mutations have been reported mainly in relapsing or resistant patients. In primary resistant patients, only few mutations have been documented so far, suggesting alternative mechanisms. We aimed to investigate if alpha 1 acid glycoprotein (AGP), an acute phase drug binding protein, could be a biological marker for pharmacological resistance to imatinib in nine patients in acute phase CML. All patients (3/3) with high AGP dosages (2.31+/-0.17 mg/mL; normal values, 0.5-1.3mg/mL) were primary resistant to imatinib whereas an early clinical response was observed for the six patients with normal AGP levels (1.13+/-0.2mg/mL). No mutation in the adenosine triphosphate domain of Abl were detected before the initiation of imatinib therapy. By using in vitro tests combining various imatinib concentrations (1-10 microM) with purified human AGP (1 and 3 mg/mL), we demonstrate that imatinib-induced apoptosis of K562 or fresh leukemic CML cells is abrogated or reduced. The same effect was observed using sera from donors with high AGP levels (1.9-3.28 mg/mL). In patients with CML in blastic phase, AGP levels could reflect pharmacological resistance to imatinib, suggesting that increased dosage of imatinib or the use of a competitor to drug binding should be recommended to optimize the therapeutic effect of the drug.

Antineoplastic Agents↗
PubMed2003

PML-RARA-targeted DNA vaccine induces protective immunity in a mouse model of leukemia.

Despite improved molecular characterization of malignancies and development of targeted therapies, acute leukemia is not curable and few patients survive more than 10 years after diagnosis. Recently, combinations of different therapeutic strategies (based on mechanisms of apoptosis, differentiation and cytotoxicity) have significantly increased survival. To further improve outcome, we studied the potential efficacy of boosting the patient's immune response using specific immunotherapy. In an animal model of acute promyelocytic leukemia, we developed a DNA-based vaccine by fusing the human promyelocytic leukemia-retinoic acid receptor-alpha (PML-RARA) oncogene to tetanus fragment C (FrC) sequences. We show for the first time that a DNA vaccine specifically targeted to an oncoprotein can have a pronounced effect on survival, both alone and when combined with all-trans retinoic acid (ATRA). The survival advantage is concomitant with time-dependent antibody production and an increase in interferon-gamma (IFN-gamma). We also show that ATRA therapy on its own triggers an immune response in this model. When DNA vaccination and conventional ATRA therapy are combined, they induce protective immune responses against leukemia progression in mice and may provide a new approach to improve clinical outcome in human leukemia.

Animals↗
PubMed2003

Combined treatment with arsenic trioxide and all-trans-retinoic acid in patients with relapsed acute promyelocytic leukemia.

PURPOSE: Arsenic trioxide (ATO) is capable of inducing a high hematologic response rate in patients with relapsed acute promyelocytic leukemia (APL). Preclinical observations have indicated that all-trans-retinoic acid (ATRA) may strongly enhance the response to ATO. PATIENTS AND METHODS: Between 1998 and 2001, we conducted a randomized study of ATO alone versus ATO plus ATRA in 20 patients with relapsed APL, all previously treated with ATRA-containing chemotherapy. The primary objective was to demonstrate a significant reduction in the time necessary to obtain a complete remission (CR) in the ATO/ATRA group compared with the ATO group. Secondary objectives were safety and molecular response. RESULTS: The CR rate after one ATO with or without ATRA induction cycle was 80%. Clinical and pharmacokinetic observations indicated that the main mechanism of action of ATO in vivo was the induction of APL cell differentiation. Hematologic and molecular response, time necessary to reach CR, and outcome were comparable in both treatment groups. Of 16 CR patients, three patients who reached a molecular remission after one induction cycle had all received chemotherapy for a treatment-induced hyperleukocytosis. Three additional patients who received further additional ATO with or without ATRA cycles converted later to molecular negativity. CONCLUSION: ATRA did not seem to significantly improve the response to ATO in patients relapsing from APL. Other potential combinations, including ATO plus chemotherapy, have to be tested.

Adult↗
PubMed2003

Arsenic trioxide induces apoptosis of cutaneous T cell lymphoma cells: evidence for a partially caspase-independent pathway and potentiation by ascorbic acid (vitamin C).

Arsenic trioxide (As2O3) displays apoptogenic properties against various types of hematopoietic malignancies. We investigated the effects of As2O3 on the viability of the cutaneous T cell lymphoma cell lines HuT-78, SeAx, and Myla, and of peripheral blood mononuclear cells from patients with Sézary syndrome, by using propidium iodide and annexin-V staining, terminal deoxyuridine triphosphate nick end labeling (TUNEL), cell cycle analysis, mitochondrial transmembrane potential (delta psi(m)) alterations, cytochrome c release, and detection of processed caspase-3. We also report in vivo effects of As2O3 in two patients with cutaneous T cell lymphoma. The results show that As2O3 induces apoptosis of cutaneous T cell lymphoma lines and of Sézary cells from patients in a time- and concentration-dependent manner in vitro, as demonstrated by annexin-V staining, mitochondrial depolarization, and DNA fragmentation. Ascorbic acid 100 microM potentiated As2O3-induced Sézary cell death, whereas interferon-alpha had no synergistic effect. As2O3-induced Sézary cell death involves activation of caspase-3, cleavage of poly(ADP-ribose)polymerase, and cytochrome c release, but was only partially inhibited by the pancaspase inhibitor Z-VAD.fluoromethylketone. Finally, As2O3 was administered to two patients with cutaneous T cell lymphoma, allowing us to obtain a partial response in one case, whereas stability was observed in the second patient. These results demonstrate that As2O3 synergizes with ascorbic acid to induce Sézary cell death at clinically achievable concentrations, through a caspase-partially independent pathway, and provide a rationale for further in vivo studies addressing the therapeutic efficacy of As2O3 in cutaneous T cell lymphoma patients.

Aged↗
PubMed2002

In vivo activation of cAMP signaling induces growth arrest and differentiation in acute promyelocytic leukemia.

Differentiation therapy for acute myeloid leukemia uses transcriptional modulators to reprogram cancer cells. The most relevant clinical example is acute promyelocytic leukemia (APL), which responds dramatically to either retinoic acid (RA) or arsenic trioxide (As(2)O(3)). In many myeloid leukemia cell lines, cyclic adenosine monophosphate (cAMP) triggers growth arrest, cell death, or differentiation, often in synergy with RA. Nevertheless, the toxicity of cAMP derivatives and lack of suitable models has hampered trials designed to assess the in vivo relevance of theses observations. We show that, in an APL cell line, cAMP analogs blocked cell growth and unraveled As(2)O(3)-triggered differentiation. Similarly, in RA-sensitive or RA-resistant mouse models of APL, continuous infusions of 8-chloro-cyclic adenosine monophosphate (8-Cl-cAMP) triggered major growth arrest, greatly enhanced both spontaneous and RA- or As(2)O(3)-induced differentiation and accelerated the restoration of normal hematopoiesis. Theophylline, a well-tolerated phosphodiesterase inhibitor which stabilizes endogenous cAMP, also impaired APL growth and enhanced spontaneous or As(2)O(3)-triggered cell differentiation in vivo. Accordingly, in an APL patient resistant to combined RA-As(2)O(3) therapy, theophylline induced blast clearance and restored normal hematopoiesis. Taken together, these results demonstrate that in vivo activation of cAMP signaling contributes to APL clearance, independently of its RA-sensitivity, thus raising hopes that other myeloid leukemias may benefit from this therapeutic approach.

Animals↗
PubMed2002

Management of disease-related anemia in patients with multiple myeloma or chronic lymphocytic leukemia: epoetin treatment recommendations.

Multiple myeloma (MM) and chronic lymphocytic leukemia (CLL) patients often develop anemia due to the disease process and effects from disease therapy. Blood transfusion, the established treatment, has an immediate effect in improving patients' hemoglobin levels. However, this effect is transient and transfusion is associated with several risks, including infections and mild to life-threatening immunologic reactions. A newer option is recombinant human erythropoietin (epoetin); a biological treatment that leads to increased hemoglobin levels over an extended time without the risks of blood transfusion. Extensive evidence has shown that epoetin is effective in the treatment of cancer-associated anemia. An international expert panel met to develop treatment recommendations for the use of epoetin in MM and CLL patients. Based on the available data, it is recommended that treatment be initiated only after other possible causes of anemia are eliminated. Epoetin should be administered to any patient with hemoglobin < or=10 g/dl. Patients with hemoglobin 10-12 g/dl should receive epoetin if they suffer from significant symptoms of anemia and/or have progressively decreasing hemoglobin values. Dosage should be initiated at 10 000 IU three times/week or 40 000 IU once/week and be titrated to maintain hemoglobin at 12 g/dl. Nonresponsive patients (<1 g/dl increase over four weeks) may have their dose increased to 20 000 IU three times/week or 60 000 IU once/week, respectively. Epoetin treatment should be discontinued if there is no response to the increased dosage, or hemoglobin >14 g/dl. Treatment should resume for patients who exceed 14 g/dl, at a reduced dosage, if their hemoglobin falls below 12 g/dl.

Anemia↗
PubMed2002

Comparable efficacy of epoetin alfa for anemic cancer patients receiving platinum- and nonplatinum-based chemotherapy: a retrospective subanalysis of two large, community-based trials.

BACKGROUND: Data from two large, community-based clinical trials that evaluated the efficacy of epoetin alfa in anemic cancer patients receiving chemotherapy were retrospectively analyzed to determine if clinical outcomes were different depending on whether chemotherapy was platinum- or nonplatinum-based. PATIENTS AND METHODS: Patients received epoetin alfa 150-300 IU/kg (Glaspy: Study 1; n = 2,342) or 10,000-20,000 IU (Demetri: Study 2; n = 2,370) s.c. three times each week for 4 months. Efficacy end points were changes in transfusion requirements, hemoglobin (Hb) levels, and quality of life (QOL). A total of 4,298 out of 4,712 patients (platinum-based, n = 1,601; nonplatinum-based, n = 2,697), who both received chemotherapy and had available data, were eligible for this retrospective analysis. RESULTS: Baseline characteristics across groups were comparable with few exceptions, which were anticipated in view of the characteristics of the two different chemotherapy types. Decreases in transfusion requirements after 2, 3, and 4 months were significant, regardless of chemotherapy type. Mean increases in Hb level from baseline to final evaluation ranged from 1.6 g/dl to 2.0 g/dl across study groups and were significant, regardless of chemotherapy type. QOL, as measured by the Linear Analog Scale Assessment (LASA), improved significantly by 20%-43%, regardless of chemotherapy type, and improvements were associated with increases in Hb. Epoetin alfa was well tolerated in both studies, regardless of chemotherapy type. CONCLUSION: Treatment of anemic cancer patients with epoetin alfa results in significant reduction in transfusion requirements, increase in Hb levels, and improvements in QOL, regardless of whether the chemotherapy is platinum- or nonplatinum-based.

Anemia↗