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Biomedical subjects

R Bouabdallah

Publications and source records attributed to R Bouabdallah.

At least 55 records · Page 3Linked to original sources
PubMed1999

Positive selection of CD34+ peripheral blood progenitor cells in patients with low-grade lymphoid malignancies and bone marrow involvement.

PURPOSE: 16 patients with low-grade lymphoid malignancies and bone marrow involvement were transplanted with selected CD34 positive Peripheral Blood Progenitor Cell (PBSC) prepared from autologous aphereses. PATIENT AND METHODS: All but one patients were mobilized with a combination of chemotherapy (including high-dose cyclophosphamide and VP16 or adriamycin, aracytin with cysplatyl) and recombinant human Granulocyte Colony-Stimulating Factor (rhG-CSF). RESULTS: A median of 3 (range, 1 to 9) aphereses yielded 15.35 x 10(6) CD34+ cells/kg (range, 4.45 to 70.88). A median of 5.01 x 10(6) adsorbed CD34+ cells/kg (range 2.01 to 24.13) was obtained after selection (median purity: 86%; range, 59-99%). The CD34 PBSC were infused one day after either one of two conditioning regimens: 11 patients received the association of cyclophosphamide (120 mg/kg) and TBI (8Gy), and 5 patients received the BEAM regimen. No recombinant hematopoietic growth factor was used after cell reinfusion. Median days to 0.5 x 10(9)/l neutrophils and 50 x 10(9)/l platelets were 13 (range, 9 to 18) and 16 (range, 11 to 35), respectively. The median number of red blood cell (RBC) unit transfusions was 4 (range, 0 to 10). The median number of platelet transfusions was 3.5 (range, 0 to 8). No individual received backup PBSC, nor required platelet transfusion beyond 3 months post-transplant. CONCLUSION: This study confirms the feasability of using blood CD34 cells to support hematopoietic recovery after myelo-suppressive or myelo-ablative regimens, in patients with low-grade NHL.

Adult↗
PubMed1999

Fludarabine alone compared to CHVP plus interferon in elderly patients with follicular lymphoma and adverse prognostic parameters: a GELA study. Groupe d'Etudes des Lymphomes de l'Adulte.

BACKGROUND: Fludarabine was associated with a good response and was well tolerated in patients with follicular lymphoma in phase II trials and this treatment may be associated with less adverse events than treatment with CHVP plus interferon in elderly patients. PATIENTS AND METHODS: One hundred thirty-one patients older than 59 years with a follicular lymphoma and poor prognosis were randomized between the association of CHVP (12 cycles in 18 months) plus interferon (5 MU TIW for 18 months) or fludarabine alone (25 mg/m2/d x 5 days for 6 cycles, then 20 mg/m2/day for 6 further cycles for 18 months). Poor prognosis was defined by the presence of a large tumor mass, poor performance status, the presence of B symptoms, above normal LDH level, or > or = 3 mg/l beta-microglobulin level. RESULTS: Patients treated with CHVP plus interferon had a higher response to treatment, a longer time to progression and a longer survival than those treated with fludarabine alone (P < 0.05 for all analyses). With a median follow-up of 29 months, the 2-year failure-free survival was 63% for the CHVP-plus-interferon arm compared to 49% for the fludarabine arm and the two-year survival was 77% and 62%, respectively. This benefit was confirmed in a multivariate analysis including initial prognostic parameters. Fludarabine alone was associated with less neutropenia than CHVP plus interferon. Interferon was decreased or stopped in 39% of the patients because of severe fatigue. CONCLUSIONS: CHVP plus interferon over 18 months was associated with a better outcome, even though the combination of interferon plus chemotherapy was less well tolerated than fludarabine.

Aged↗
PubMed1999

Intensive sequential chemotherapy (ISC 95) with growth factors and blood stem cell support in high-intermediate and high-risk (IPI 2 and IPI 3) aggressive non-Hodgkin's lymphoma: an oligocentric report on 42 patients.

We previously reported feasibility and efficacy of a monocentric pilot study of intensive sequential chemotherapy (ISC) in poor-risk aggressive non-Hodgkin's lymphoma (NHL) in patients < 60 years. To validate these results on a large cohort of patients, we designed a new and oligocentric study. After a COP (cyclophosphamide (Cy), vincristine (Vcr), prednisone (Pred) debulking, patients received four courses of high-dose CHOP (Cy, doxorubicin (Doxo), Ver, Pred), with the addition of etoposide and cisplatin during the two last courses. G-CSF was delivered after each cycle, and peripheral blood stem cells (PBSC) were used to support the two last cycles. Total duration of chemotherapy was 13 weeks, with a planned dose-intensity (DI) of 1420 mg/m2/week and 23 mg/m2/week for Cy and Doxo, respectively. Radiotherapy (involved fields) was then delivered for patients with node size > or = 5 cm at diagnosis. Forty-two patients were enrolled in this study; 36 completed the treatment and received 75% or more of the planned DI for both Cy and Doxo. Median duration of grade 4 neutropenia was 14 days (range, 2 to 28) for the regimen as a whole, and median duration of rehospitalization for febrile neutropenia was 18 days (range, 4 to 41). Overall response rate was 83%, with 29 patients (69%) in complete response (CR). Six patients failed to respond and one died of toxicity. With a median follow-up of 22.5 months (range, 10 to 42), the 3-year event-free survival (EFS) is 55% (95% CI, 39-71), while disease-free survival (DFS) is 79% (95% CI, 63-95). Ambulatory ISC is accessible and feasible in an oligocentric study. PBSC allow repeated delivery of high-dose chemotherapy cycles, and result in encouraging CR, EFS, and DFS rates for poor-risk aggressive NHL's patients.

Adult↗
PubMed1999

A phase II trial of induction and consolidation therapy of acute myeloid leukemia with weekly oral idarubicin alone in poor risk elderly patients.

We have conducted a phase II outpatient trial testing weekly oral administration of idarubicin (ZAVEDOS-ZVD) alone to determine the rate of objective response and toxicity in poor risk acute myeloid leukemia (AML) patients over 60 years of age. The treatment consisted of three phases: induction, with 20 mg/m2 of ZVD on days 1, 8, 15 and 22; consolidation with 20 mg/m2 of ZVD for 4 weeks; and maintenance with six cycles lasting 3 months and consisting of oral 6 mercapto-purine 2 mg/kg/day, 4 days a week for 2 months; subcutaneous cytarabine 1 mg/kg, once a week for 2 months; and oral ZVD 20 mg/m2 on day 1 and day 8 of the third month. In case of failure after induction course, patients received salvage treatment with 4 weekly oral doses of 40 mg/m2 ZVD. Fifty-one patients with a median age of 76 years were enrolled and could receive induction course. Of these 51 patients, 37 could receive subsequent courses, which consisted either of consolidation, or salvage. Only 11 patients underwent maintenance treatment. Sixty-three percent of patients had to be hospitalized during induction, for a median duration of 14.5 days, and 87% required hospitalization during salvage for a median duration of 17.5 days. Only five patients (38%) required hospitalization during consolidation. There were three toxic deaths (6%), two from hemorrhage and one from pulmonary embolism. The overall response rate was 29%, with 12 patients in complete response (25%) and two in partial response (4%). The median overall survival rate is 4 months for the whole population, and the median DFS is 9.6 months among the 14 responding patients. The results of this trial show that this new weekly schedule of oral ZVD chemotherapy is feasible and effective in poor risk elderly patients with AML. This regimen may be helpful for patients unable to tolerate intensive intravenous regimens, and is a real alternative to palliative treatments.

Acute Disease↗
PubMed1999

Quantitative analysis detects ubiquitous expression of apoptotic regulators in B cell non-Hodgkin's lymphomas.

To determine whether the expression levels of Bcl-2 family apoptotic regulators are correlated with the histopathological heterogeneity of B cell non-Hodgkin's lymphomas (NHL), we quantified their expression in malignant B cell populations isolated from 33 biopsy samples, including small lymphocytic lymphoma (SLL, n = 9), mantle cell lymphoma (MCL, n = 8), follicular lymphoma (FL, n = 8), and diffuse large cell lymphoma (DLCL, n = 8). Normal B cells purified from reactive lymph nodes and tonsil (n = 3) were used as controls. Cell lysates were analyzed by Western blotting, and signals quantified by densitometry. Expression of Bcl-2 and its homologues, Bcl-xL, Bcl-xS, Bax, Bad, Bak and Bag-1, was detected in all NHL cases, with wide variations between histological subtypes and within each subtype. Statistically significant differences were: (1) a higher level of Bad expression in DLCL compared to FL and MCL; (2) a lower level of Bak expression in FL compared to DLCL, SLL and MCL; and (3) a higher Bag-1 expression level in FL compared to SLL. When compared to NHL cells, normal B cells showed a higher level of Bax expression, and a lower level of Bcl-xL expression. Thus, quantitative analysis shows ubiquitous expression of Bcl-2 family proteins in normal and neoplastic B cells; the variations in expression levels may contribute to both the B-NHL clinicopathological diversity and the different apoptotic sensitivities of normal B cells vs B-NHL cells.

Apoptosis↗
PubMed1999

FADD expression and caspase activation in B-cell lymphomas resistant to Fas-mediated apoptosis.

We have previously shown that malignant B cells from non-Hodgkin's lymphomas (NHL) are resistant to Fas-mediated apoptosis. To determine the mechanisms underlying this resistance, we analysed by Western blotting the expression of several apoptotic regulators, caspase 3, caspase 8, FADD and poly(ADP-ribose) polymerase (PARP) in fresh lymphoma cells, isolated from 16 B-NHL biopsy samples of different histological subtypes, and displaying variable levels of Fas expression. The profiles of expression of these apoptotic regulators were monitored in cell lysates at different times following Fas with or without CD40 stimulation. Expression of FADD and of the uncleaved forms of PARP, caspase 3 and caspase 8 were detected in all untreated NHL samples. Low levels of PARP cleavage were noted in three untreated samples. Fas stimulation alone induced neither significant apoptosis nor significant changes in the expression profiles of FADD, caspases 3 and 8 and PARP in the 16 samples, except for variations in FADD and caspase 8 expression levels in a minority of samples. Fas/CD40 co-stimulation induced apoptosis and cleavage of caspase 3, caspase 8 and PARP in the five NHLs tested; expression of FADD was not modified. Our results showed (1) that induction of apoptosis in B-NHLs by Fas/CD40 co-stimulation used the same caspase executioner machinery as the normal Fas pathway, and (2) that NHL cells which resisted Fas-mediated apoptosis displayed no defect in either expression or functionality of caspases 3 and 8, nor in FADD expression. The dysfunction underlying NHL resistance to apoptosis must therefore lie upstream of caspase 8, or could alternatively be influenced by anti-apoptotic regulators of the Bcl-2 family.

Adaptor Proteins, Signal Transducing↗
PubMed1998

Analysis of BAX expression in human tissues using the anti-BAX, 4F11 monoclonal antibody on paraffin sections.

BAX, a heterodimer partner of BCL-2, is an apoptosis inducer. We aimed to characterize the distribution of the BAX protein in normal adult human tissues using immunohistochemistry (IHC). The monoclonal antibody anti-BAX 4F11 was used on paraffin sections: immunodetection of BCL-2 was performed simultaneously on serial sections. The specificity of BAX IHC staining was verified by Western blot analysis. IHC positivity was correlated with the detection of a specific 21 kDa band on Western blots. BAX immunostaining was mainly cytosolic and occasionally on the nuclear membrane. Amounts of BAX protein were high in liver, renal tubules, endocrine islets of the pancreas, gastric glands, cardiac muscle, epididymis, lymph node germinal centers, and neurons; intermediate in the colon, stomach, bronchus. Fallopian tube, salivary gland, breast, thymus, spleen, and testis; low or undetectable in the other tissues. BAX IHC positivity correlated with apoptotic features in neurons and germinal center lymphocytes. There was no strict correlation between the IHC profiles of BAX and BCL-2 expression, although a reciprocal pattern of staining was observed in lymph node and colon. This report shows the usefulness the monoclonal antibody anti-BAX 4F11 on paraffin sections and demonstrates that the human BAX tissular distribution is close to, but not similar, to the profile observed in the mouse. The widespread BAX expression suggests that BAX alone is insufficient to trigger cell death in human tissues. BAX may either modulate the role of other regulators of apoptosis or carry out functions unrelated to apoptosis.

Animals↗
PubMed1998

Role of induction chemotherapy and bone marrow transplantation in adult lymphoblastic lymphoma: a report on 62 patients from a single center.

OBJECTIVE: To describe the outcome of an unselected large series of patients with lymphoblastic lymphoma (LBL) treated in a single institution. PATIENTS AND METHODS: Sixty-two patients were treated between 1980 and 1992. Induction chemotherapy (CT) to achieve complete response (CR) was: French Multicenter Acute Lymphoblastic Leukemia (ALL) protocols (38), non-Hodgkin's Lymphoma (NHL) protocols (20). Thirty patients underwent transplant after achieving CR (allogeneic 12; autologous 18). RESULTS: Forty-six patients (74%) achieved CR and 16 (26%) failed to respond. The patients who received an ALL induction had an 89% CR rate, while the CR rate was 52% in patients who received a NHL-like regimen. With a median follow-up of 93 months (range 36-187), the actuarial overall survival (OS) rate for all patients is 49% at five years and 41% at 10 years, and the actuarial event-free survival (EFS) rate is 45% and 37%. OS and EFS in the grafted population are, respectively, 60% and 56% at five years. Our results also show a trend toward a longer OS in allografted group. CONCLUSIONS: ALL induction therapy is more effective than the NHL-like regimen for augmenting the CR rate. Autologous or allogeneic transplantation should be considered as consolidation therapy in high-risk group patients.

Adolescent↗
PubMed1998

Sensitivity to Fas-mediated apoptosis is null or weak in B-cell non-Hodgkin's lymphomas and is moderately increased by CD40 ligation.

The Fas receptor (APO-1/CD95) is capable of inducing apoptosis of lymphoid cells and is expressed in some non-Hodgkin's lymphomas (NHLs). Fas expression is up-regulated at the surface of normal B cells upon triggering of the CD40 receptor. In this report, we investigated the sensitivity of NHLs to Fas-mediated apoptosis induced by anti-Fas monoclonal antibodies (MAbs) and its possible modulation by CD40 ligation in 18 NHL biopsy samples of various histological subtypes. Flow cytometric analysis showed that the fraction of Fas-expressing lymphoma cells was highly variable from sample to sample (from 1% to 93%, mean value 46%). The frequency of apoptotic cells was not significantly increased upon treatment with an anti-Fas MAb compared with control MAb in the 18 NHL cases analysed. The sensitivity of lymphoma cells to Fas-mediated apoptosis was correlated neither with the histological subtypes nor with the level of Fas expression. Activation of neoplastic B cells by CD40 ligation resulted in significant increases in Fas expression and Fas-induced apoptosis among the five B-NHL cases tested. The overall increase in apoptotic rates was moderate and remained lower in tumour samples than in control CD40-activated normal tonsil B cells. Altogether, our results indicate that the sensitivity to Fas-induced apoptosis is null or weak in NHL cells, irrespective of their histological subtype, and that it can be increased to a moderate and variable degree by CD40 ligation on neoplastic B cells. This may be an impediment to the development of Fas-based therapies for NHLs.

Apoptosis↗
PubMed1998

Early intensive therapy with autologous stem cell transplantation in advanced Hodgkin's disease: retrospective analysis of 158 cases from the French registry.

This retrospective study was undertaken to evaluate cure rates, toxicity and late effects of early intensive therapy followed by autologous stem cell transplantation (ASCT) in patients with advanced Hodgkin's disease (HD). One hundred and fifty-eight cases of ASCT registered in the French database (SFGM) were retrospectively analyzed. Disease status at the time of ASCT was first partial response (PR) in 85, first complete remission (CR1) in 45 or primary refractory in 28 cases. The median time interval between diagnosis and ASCT was 7 months (range 4-13). At the time of analysis in December 1995, 121/158 patients (76.6%) were alive, including 111 (70.2%) in continuous CR with a median follow-up for surviving patients of 46 months (range 8-123). Peri-ASCT toxic death rate was 3%, and the actuarial risk of new malignancies was 4.9% at 5 years. The cumulative probability of 5-year overall survival (OS) was 75.2% for the entire group of patients, 80.6% for the chemosensitive ones, and 33.9% for the primary refractory (chemosensitive vs refractory, P < 0.0001). The cumulative probability of 5-year event-free survival (EFS) was 66.1% for the entire group of patients, 73.7% for the chemosensitive ones, and 26.1% for the primary refractory (chemosensitive vs refractory, P < 0.0001). The only significant prognostic factor for both OS and EFS was disease status at the time of ASCT. Early ASCT in advanced HD is feasible, with a low risk of toxicity and without a higher rate of late effects compared with conventional treatment. Results achieved in chemosensitive patients at the time of transplantation lay the basis of future prospective randomized trials comparing ACST as front-line treatment to conventional treatment in high-risk cases.

Adolescent↗
PubMed1998

High-dose methotrexate for the treatment of primary cerebral lymphomas: analysis of survival and late neurologic toxicity in a retrospective series.

PURPOSE: The impact of treatment options on survival and late neurologic toxicity was investigated in a series of patients with primary cerebral lymphoma (PCL) and no known cause of immunosuppression. PATIENTS AND METHODS: Prognostic factors for survival and treatment-induced late neurotoxicity were investigated in a retrospective series of 226 patients with PCL. RESULTS: With a median follow-up of 76 months, the median overall survival was 16 months and 5-year survival was 19%. In a univariate analysis, age greater than 60 years, performance status, CSF protein level greater than 0.6 g/L, involvement of corpus callosum or subcortical grey structures, detectable lymphoma cells in CSF, increased serum lactate dehydrogenase (LDH), but not histological subtype, were significantly correlated with a poor survival. Treatment with chemotherapy versus radiotherapy alone (P = .05), high-dose methotrexate (HDMTX; P = .0007), and cytarabine (P = .04) correlated with a better survival in univariate analysis. Using the Cox model, age, performance status, and CSF protein were independently correlated with survival. After adjustment of these factors, treatment with an HDMTX-containing regimen remained the only treatment-related factor independently correlated with survival (P = .01). The projected incidence of treatment-induced late neurotoxicity was 26% at 6 years in this series, with a median survival from the diagnosis of late neurotoxicity of 12 months. Treatment with radiotherapy followed by chemotherapy was the only parameter correlated with late neurotoxicity in multivariate analysis (relative risk, 11.5; P = .0007). CONCLUSION: Patients with PCL treated with regimens that included HDMTX followed by radiotherapy have an improved survival, but not a higher risk of late neurotoxicity as compared with other treatment modalities in this series.

Adolescent↗
PubMed1998

Doxorubicin-containing regimen with or without interferon alfa-2b for advanced follicular lymphomas: final analysis of survival and toxicity in the Groupe d'Etude des Lymphomes Folliculaires 86 Trial.

PURPOSE: To compare progression-free survival (PFS), overall survival (OS), and toxicity of a doxorubicin-containing regimen administered alone or in combination with interferon alfa-2b (IFNalpha) in patients with low-grade follicular lymphoma (FL) and poor prognostic factors. PATIENTS AND METHODS: Two hundred sixty-eight patients with advanced-stage FL received cyclophosphamide, doxorubicin, teniposide, and prednisone (CHVP) monthly for 6 months, then every 2 months for 12 months. After randomization, 242 patients were evaluated for efficacy: 119 received CHVP alone, and 123 also received IFNalpha at a dose of 5 million units three times weekly for 18 months. RESULTS: After a 6-year median follow-up, the patients treated with CHVP + IFNalpha showed significantly longer median PFS than those who received CHVP alone (2.9 years v 1.5 years, respectively; P = .0002) and significantly longer median OS (not reached v 5.6 years, respectively; P = .008). Although some side effects, which included neutropenia, asthenia, fever, elevated serum transaminase levels, flu-like symptoms, and thrombocytopenia, were more frequently observed in patients who received the combination regimen, these reactions were moderate. IFNalpha was withdrawn because of toxicity in 10% of the patients, and a dosage reduction or temporary suspension was required in 28%. CONCLUSION: With long-term follow-up of 6 years, these results confirm that the addition of IFNalpha to a doxorubicin-containing regimen for patients with advanced-stage and clinically aggressive FL not only increased PFS, as in most other similar trials, but also prolonged OS. Toxicity was moderate. The beneficial effects of this combined chemotherapy and IFNalpha regimen on OS probably reflect the selection of FL patients with poor prognostic factors.

Antineoplastic Agents↗
PubMed1998

Anti-GM-CSF monoclonal antibody therapy for refractory acute leukemia.

Several phase I trials and pilot studies using Monoclonal Antibody (MoAb) have been performed in B-cell neoplasms, but this approach has not until now been extensively tested in myeloid leukemias. Recently, we evaluated the use of anti-Granulocyte-Macrophage Colony-Stimulating Factor MoAb (Anti-GM-CSF MoAb) in acute myeloid leukemia (AML). Eight patients fulfilled inclusion criteria and received a single course of Anti-GM-CSF MoAb infusion during 5 to 15 days. Anti-GM-CSF MoAb was well tolerated and was detectable in pharmacokinetics studies. Using Human Anti-Rat Antibodies (HARA), we also observed an immunological response to the MoAb. Despite sufficient levels detected in the serum and biological activity of Anti-GM-CSF MoAb in vivo, no anti-leukemic effect was noted, except for one patient who had a decrease of 50% in the marrow blast cell mass. These observations indicate that leukemic proliferation in vivo involves a complex network spanning many mechanisms, and inhibition of leukemia is not effective if only one of these key targets is attacked. The development of these new approaches may be more effective in the future.

Adult↗