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C Chabannon

Publications and source records attributed to C Chabannon.

At least 55 records · Page 3Linked to original sources

Preferential photoinactivation of leukemia cells by aluminum phthalocyanine.

The efficacy of chloroaluminum phthalocyanine (AlPc) for photodynamic therapy (PDT) has been evaluated in vitro on acute myeloid leukemia (AML) cells, normal peripheral blood leukocytes (PBL) and mobilized peripheral blood stem cells (mPBSC). The selectivity of the treatment has been evaluated by mixing PBL and TF-1, an erythroleukemic cell line. Upon photoradiation, this photosensitizer leads to a significant and preferential photokilling of leukemia cells in comparison to normal cells. The use of stimulated lymphocytes in PBL/TF-1 mixtures instead of resting cells also leads to a preferential killing towards TF-1 although activated PBL are more affected than resting PBL. The analysis of AlPc intracellular emission by flow cytometry shows that the uptake of the dye by leukemia cells is faster. This good efficacy towards AML and the observed lower phototoxicity towards normal cells (PBL, normal progenitors) suggest that this phthalocyanine is a potential bone marrow purging agent.

Aluminum↗

High-dose chemotherapy followed by reinfusion of selected CD34+ peripheral blood cells in patients with poor-prognosis breast cancer: a randomized multicentre study.

Seventy-one patients with poor-prognosis breast cancer were enrolled after informed consent in a multicentre randomized study to evaluate the use of selected peripheral blood CD34+ cells to support haematopoietic recovery following high-dose chemotherapy. Patients who responded to conventional chemotherapy were mobilized with chemotherapy (mainly high-dose cyclophosphamide) and/or recombinant human granulocyte colony-stimulating factor (rhG-CSF). Patients who reached the threshold of 20 CD34+ cells per microl of peripheral blood underwent apheresis and were randomized at that time to receive either unmanipulated mobilized blood cells or selected CD34+ cells. For patients in the study arm, CD34+ cells were selected from aphereses using the Isolex300 device. Fifteen patients failed to mobilize peripheral blood progenitors and nine other patients were excluded for various reasons. Forty-seven eligible patients were randomized into two comparable groups. CD34+ cells were selected from aphereses in the study group. Haematopoietic recovery occurred at similar times in both groups. No side-effect related to the infusion of selected cells was observed. The frequency of epithelial tumour cells in aphereses was low (8 out of 42 evaluated patients), as determined by immunocytochemistry. We conclude that selected CD34+ cells safely support haematopoietic recovery following high-dose chemotherapy in patients with poor-prognosis breast cancer.

Adult↗

Mobilisation of healthy donors with lenograstim and transplantation of HLA-genoidentical blood progenitors in 54 patients with hematological malignancies: a pilot study.

Blood cell transplantation (BCT) is now common practice in the autologous setting. We performed a pilot study of allogeneic BCT, collected after the priming of an HLA-identical sibling with a glycosylated rhu-G-CSF (lenograstim) (10 microg/kg). Fifty-four patients were included (38 +/- 11; M/F = 33/21; CML (n = 17), AML (n = 14), ALL (n = 15); MDS (n = 8)). Transplant procedures were standard (TBI regimen = 47 (87%); MTX-CsA: n = 37; CsA-PDN: n = 17). No serious adverse events were reported in donors. A median of 11 (3.5-29.1) x 10(6)/kg CD34+ cells, 332 (33-820) x 10(6)/kg CD3+ cells were collected. Four patients did not engraft (early death: n = 2; graft failure: n = 2). Fifty-one patients initially recovered 0.5 x 10(9)/l ANC and 25 x 10(9)/l platelets at 15 (10-30) and 13 (9-188) days. 29/51 and 29/38 experienced grade > or =2 acute and chronic GVHD. With a median follow-up of 25 months (18-36), relapse rate is 16% +/- 8, survival and DFS probabilities are similar (50% +/- 13). A better outcome is documented for patients under 45 years and in the early phase of the disease (n = 28), with an identical survival and DFS of 71% +/- 13. In conclusion, lenograstim is a potent rhu-G-CSF for mobilisation of allogeneic hematopoietic progenitors. Two-year follow-up indicates good haematological recovery but some concerns about graft failure and chronic GVHD have arisen deserving prospective evaluation.

Adjuvants, Immunologic↗

Second neoplasms following high-dose chemotherapy and autologous stem cell transplantation for malignant lymphomas: a report of six cases in a cohort of 171 patients from a single institution.

High dose chemotherapy with autologous stem cell transplantation (ASCT) is increasingly used in the treatment of patients with lymphoma. As previously shown with conventional treatments, second neoplasms are emerging as a long term complication of the procedure. In this study, we investigate the incidence of second neoplasm in a cohort of 171 patients treated with BEAM or BEAC regimens for Hodgkin's disease (n = 62) and non-Hodgkin's lymphomas (n = 109) followed up for a median of 52 months post ASCT. Six patients developed six second malignancies 12 to 105 months after ASCT: fibrolamellar carcinoma of the liver, malignant fibrous histiocytoma, pancreatic carcinoma, squamous cell carcinoma of the lung, invasive carcinoma of the vulva and acute myelogenous leukemia. The cumulative actuarial risk for developing second malignancy is 16.7% (95% confidence interval: 5.9-39.3%) 13 years after transplant. The age-adjusted incidence of cancer in the study group is 4.1 times higher than that of primary cancer in the general population. These data confirm that ASCT recipients are at increased risk of later malignancies. This complication adds significant morbidity and mortality to the transplant process and therefore, needs to be taken into account in long term evaluation of new strategies which involve early intensification in the treatment of lymphomas.

Adolescent↗

A neutralizing anti-TGF-beta1 antibody promotes proliferation of CD34+Thy-1+ peripheral blood progenitors and increases the number of transduced progenitors.

The subset of blood cells that expresses both CD34 and Thy1 (CD90) cell surface molecules is enriched in hematopoietic stem cell activity and can be obtained from the peripheral blood of cancer patients after mobilization by chemotherapy and granulocyte colony-stimulating factor (G-CSF). Because transforming growth factor-beta1 (TGF-beta1) is a potent inhibitor of hematopoietic progenitor proliferation and differentiation, in this study we analyzed the impact of neutralizing TGF-beta1 activity during culture and retroviral transduction of CD34+Thy1+ cells. When purified CD34+Thy1+ cells were cultured in the presence of a neutralizing antibody against TGF-beta1, the percentage of cycling cells, proliferation, and absolute number of clonogenic progenitors were increased in comparison to the cultures performed without the addition of antibody. Antibody-mediated neutralization of TGF-beta1 during retroviral transduction performed by coculture of CD34+Thy1+ cells with a MFG-S-nlsLacZ retroviral vector-producing cell line did not affect the percentage of transduced progenitors as assessed by direct X-Gal staining of colonies in clonogenic assays. However, due to the better expansion of CD34+Thy1+ cells in the presence of anti-TGF-beta1, the absolute number of transduced progenitors recovered at the end of the culture was increased.

Antibodies↗

Benefits of granulocyte-colony-stimulating factor after stem cell transfusion in intensive sequential chemotherapy for breast cancer.

The aim of this study was to evaluate the clinical and economic benefit of filgrastim given with intensive sequential chemotherapy. Women with poor-prognosis breast cancer received four cycles of high-dose cyclophosphamide (3 g/m2) and doxorubicin (75 mg/m2), followed by filgrastim 5 microg/kg/dy, stem cell collection after the cycle 1, and stem cell infusion after cycle 3 and cycle 4. The first cohort received filgrastim after the fourth cycle but the second cohort did not.Thirty three patients were included in the first cohort and 13 in the second. The results indicate that the duration of grade IV neutropenia was shorter in the group given filgrastim as was the median time to recover an absolute neutrophil count (ANC) > 1.0 x 10(9)/L. The rate and duration of the rehospitalizations were higher in the group not receiving filgrastim. We found that costs such as drugs and hospitalizations were significantly higher (p = 0.032 and p = 0.049) in the non-filgrastim-treated group. Using ANC > 1.0 x 10(9)/L as an intermediary efficiency criterion it was more cost effective to give filgrastim. It can be concluded from this study that filgrastim can decrease the duration of grade IV neutropenia in patients receiving intensive sequential chemotherapy. This, in turn, reduces the cost of hospitalization. However, in our study, this reduction of neutropenia did not have any impact on further therapy.

Adult↗

Clinical and economic comparison of lenograstim-primed blood cells (BC) and bone marrow (BM) allogeneic transplantation.

The study presented is a clinical and economic comparison of bone marrow (BM) and blood cells (BC) allogeneic transplantation. We performed a case-control study to compare 17 patients receiving allogeneic BC transplant in a pilot study to an historical group of 17 patients allografted with BM. We evaluated the clinical outcomes and the direct medical costs of transplantation from conditioning regimen until day 100 by detailed observation of patients' medical records. Patients in the BC group received a median of 8 x 10(6)/kg CD34+ cells (1.58-29.1) and 266 x 10(6)/kg CD3+ cells (128-469). All patients had neutrophil engraftment with a median of 14 days in the BC group vs 19 days in the BM group (P < 0.05). The Kaplan-Meier estimation of the median number of days to a platelet count of > 25 x 10(9)/l, independent of platelet transfusion, was significantly shorter in the BC group (15 (9-74)) compared with the BM group (25 (15-45)). Acute graft-versus-host disease (AGVHD) of grade > or = 2 was not significantly different between the two groups. Patients treated with BC presented a US$16,134 decrease in the cost of the first 100 days (29%, P = 0.006). Our comparison suggested that platelet reconstitution and total costs were in favor of the BC group.

Adjuvants, Immunologic↗

Successful reconstitution of human hematopoiesis in the SCID-hu mouse by genetically modified, highly enriched progenitors isolated from fetal liver.

Highly purified CD34++CD38-Lin- hematopoietic progenitors isolated from human fetal liver were infected with the murine retroviral vector, MFG nls-LacZ, which encodes a modified version of the Escherichia coli beta-galactosidase gene. Progenitors that were cocultured with the packaging cell line could reconstitute human bone marrow or thymus implanted in SCID-hu mice. Expression of the beta-galactosidase gene was observed in primitive and committed clonogenic progenitors, mature myeloid, B-lineage cells, and T-lineage cells for up to 4 months after injection into SCID-hu mice. Furthermore, hematopoietic reconstitution by genetically modified progenitor cells could be achieved by the injection of the cells generated from as few as 500 CD34++CD38-Lin- cells, suggesting efficient retroviral gene transfer into fetal liver progenitors.

Animals↗

Early establishment of chimerism in the B and T lymphoid lineages after transplantation of allogeneic mobilized blood cells in leukemic patients.

BACKGROUND: The use of allogeneic recombinant human granulocyte colony-stimulating factor (rhG-CSF)-mobilized blood cells was recently evaluated in patients with malignancies. METHODS: Ten patients with leukemia were transplanted with allogeneic blood cells from HLA-identical sex-mismatched siblings; blood cells were mobilized with recombinant rhG-CSF. Up to 6 months after transplantation, blood and bone marrow samples were obtained from the recipient and analyzed for the presence of donor cells, using fluorescence in situ hybridization with specific probes hybridizing to sex chromosomes. RESULTS: Analysis of blood and bone marrow smears demonstrated a complete chimera, as early as day 15 after transplantation. Furthermore, marrow and blood CD4+, CD8+, CD19+, and CD34+ cells were sorted using direct immunofluorescence and flow cytometry: fluorescence in situ hybridization analysis on sorted cells demonstrated that most progenitors and most cells in the T- and B-cell lineages were of donor origin as early as day 15 after transplantation. CONCLUSIONS: Together with recently reported results, this study demonstrates that allogeneic rhG-CSF-mobilized blood cells contain primitive hematopoietic progenitors that can repopulate all lymphoid and myeloid lineages. Establishment of chimerism seems to be quick and stable, including the T- and B-cell lineages. Although establishment of chimerism in mitogen-responsive T cells is readily assayable with conventional cytogenetics, our study provides additional insight on the reconstitution of the B lineage and T-cell subsets after allogeneic transplantation in patients with leukemia.

Adult↗

Immune reconstitution after blood cell transplantation.

Immune clinical events and pattern of recovery of total lymphocytes, T cells and CD4+/CD8+ T cell subsets, B cells and NK cells, were analysed after allogeneic blood cell transplantation (BCT) for 12 months following transplant (n = 33). Results were compared with immune recovery after allogeneic bone marrow transplantation (BMT) (n = 15) and autologous blood cell transplantation (n = 19). Rates of acute GVHD were comparable in the two allotransplantation groups. Fourteen out of 17 evaluable alloBCT group patients have presented an extensive cGVHD. Total T cell, CD4+T cells and CD56+NK cell reconstitution were improved in alloBCT group vs alloBMT group. CD4+/CD8+ ratio evolution were improved in alloBCT group vs alloBMT and autoBCT groups. These results confirm that rapid immune recovery is associated with allogeneic blood stem cell transplantation.

Adult↗

Early and fatal immune haemolysis after so-called 'minor' ABO-incompatible peripheral blood stem cell allotransplantation.

A 38-year-old man, blood group A+, was allotransplanted for multiple myeloma from his fully matched sister, blood group O+. Anti-A antibodies IgG and IgM titres of the donor were low. Allogeneic peripheral blood stem cells were harvested by leukapheresis after subcutaneous administration of G-CSF. Rapid engraftment occurred since 5.6 x 10(9)/l leukocytes were achieved on day +9 post-transplant. At this time a severe immune haemolytic syndrome occurred and direct antiglobulin test was positive (IgG and C3d). Elution showed an anti-A specificity. Evolution was rapidly unfavourable related to multiorgan failure. The patient died on day +20 post-transplant.

ABO Blood-Group System↗

High-dose sequential chemotherapy with stem cell support for non-metastatic breast cancer.

The importance of dose-intensity has been suggested in breast cancer. The aim of this study was to evaluate the feasibility of a high-dose intensity doxorubicin-cyclophosphamide regimen with supporting G-CSF and blood stem cells. Twenty-five patients with non-metastatic breast cancer received four cycles of doxorubicin (75 mg/m2) and cyclophosphamide (3000 mg/m2) at 3 week intervals. Apheresis was performed after the first cycle and if necessary after the second cycle. Stem cells were reinfused after the third and fourth cycles. G-CSF was started on day 3 of each cycle (5 microg/kg/day) and was stopped the day before the last apheresis or when absolute neutrophil count was above 0.5 x 10(9)/l. Median received dose-intensity was respectively 25 mg/m2/week (range 22-26) and 1000 mg/m2/week (range 904-1065) for doxorubicin and cyclophosphamide. Grade IV thrombocytopenia occurred in 8% of cycles. Two patients needed platelets and 12 red cell transfusion. Fifteen patients were readmitted for a median duration of 4 days (range 1-7). We have established a safe, outpatient, high-dose intensity doxorubicin-cyclophosphamide regimen with supporting G-CSF and blood stem cells which can be submitted for comparison with the current standards.

Adult↗

Intensive sequential chemotherapy with repeated blood stem-cell support for untreated poor-prognosis non-Hodgkin's lymphoma.

PURPOSE: To demonstrate the feasibility and efficacy of six ambulatory high-dose sequential chemotherapy courses that include three intensified cycles supported by stem-cell infusion in high-risk and high-intermediate-risk untreated non-Hodgkin's lymphoma (NHL) patients. PATIENTS AND METHODS: A pilot nonrandomized study included 20 untreated patients aged less than 60 years with aggressive histologically identified NHL and two or three adverse-prognosis criteria (International Index). Patients received an ambulatory regimen with high-dose chemotherapy supported by granulocyte colony-stimulating factor (G-CSF) and repeated peripheral-blood stem-cell (PBSC) infusion. The median age was 39 years (range, 20 to 59), with 13 men and seven women. Chemotherapy consisted of one cycle every 21 days for a total of six cycles. The first three cycles (A1, A2, and A3) consisted of cyclophosphamide (Cy) 3,000 mg/m2, doxorubicin (Doxo) 75 mg/m2, and vincristine 2 mg (plus corticosteroids). The last three cycles (B4, B5, and B6) consisted of the same drug combination plus etoposide 300 mg/m2 and cisplatin 100 mg/m2. For an expected duration of 18 weeks, the projected dose-intensity was 25 mg/m2/wk for Doxo and 1,000 mg/m2/wk for Cy. G-CSF 300 micrograms was administered from day 6 following each cycle until neutrophil reconstitution. Two aphereses were performed at approximately day 13 after each A cycle, and PBSCs were injected at day 4 of each B cycle. Radiotherapy on tumor masses > or = 5 cm was scheduled after completion of the last cycle. RESULTS: The median duration of grade 4 neutropenia was 1 day (range, 0 to 7) for each A cycle and 4 days (range, 1 to 10) for each B cycle (P = .02). The median duration of grade 4 thrombopenia was 0 days (range, 0 to 8) for each A cycle and 6 days (range, 1 to 21) for each B cycle (P < .001). Hospitalization for febrile neutropenia was required for 18% and 44% of patients during cycles A and B, respectively (P < .01). Only three patients did not complete the protocol: one due to emergency surgery after cycle B4, one who died after cycle B5 from interstitial pneumonia, and one with delayed hematologic reconstitution after cycle B4. Chemotherapy delivery was optimal (median actual relative dose-intensity, 97%; range, 66 to 100). The median total dose administered over 18 weeks was 18,000 mg Cy (range, 12,000 to 18,000), 450 mg Doxo (range, 300 to 450), 900 mg etoposide (range, 300 to 900), and 300 mg cisplatin (range, 100 to 300). Evaluation of response after six courses showed 13 complete remissions ([CRs] 65%), four partial remissions (PRs), two nonresponses (NRs), and one toxic death. With a median follow-up period of 25 months (range, 16 to 43), 15 patients are alive, with 12 in continuous first CR; five patients relapsed (four of four PRs and one of 13 CRs). Two-year survival and failure-free survival (FFS) rates are 73% and 56%, respectively. The disease-free survival (DFS) rate for the CRs is 86%. CONCLUSION: PBSC support contributes to the feasibility of first-line, very-high-dose, ambulatory chemotherapy delivery in poor-risk NHL and is associated with a high rate of remission and FFS.

Adult↗

[Intensive chemotherapy with autologous stem cell transplantation in ovarian cancers: analysis of 67 patients treated at the Paoli-Calmettes Institute and a review of the literature].

Despite important initial chemosensitivity, advanced ovarian cancer has a bad prognosis with a median survival of 20 to 30 months. These results might be better with intensive chemotherapy. We analysed 67 patients treated by intensive chemotherapy with autologous stem cell transplantation for advanced ovarian cancer at Institute Paoli-Calmettes between 1980 and 1994. Population was divided in two groups: salvage group (n = 30) for initial chemotherapy-refractory patients and consolidation group (n = 37) for sensitive patients. Several successive conditioning regimens were used, all based on alkylating agents. Principal toxicities were severe aplasia and mucositis. Four patients died from toxicity related to infection during strong immunosuppression. In salvage group, 9 out of 21 evaluable patients responded (43%), but duration of responses was short (median range of 5 months) and 2-year overall survival rate was 8% after transplantation. In consolidation group, 19 patients are alive and 15 are without disease progression with a median follow-up of 42 months (17, 161) after diagnosis. Five-year disease-free survival rate is 28% (median range of 35 months) and 5-year overall survival rate is 48% (median range of 41 months). Intensification does not seem to be long term beneficial for initial chemotherapy refractory patients, despite objective responses rate better than classical treatment. On the other hand, results seem better than conventional treatments in case of chemosensitive disease and should be confirmed prospectively in larger cohort of patients. Moreover, other research directions are open like intensification supported by hematopoietic growth-factors and peripheral stem cells, definition of best conditioning regimen, use of taxanes, and intensification in first line chemotherapy after initial surgery.

Adult↗

Bone marrow and blood cells as alternative sources of hematopoietic progenitors after failure of a first collection. A single institution retrospective study.

From October 1992 through October 1994, we retrospectively identified 12 patients who underwent two collections of hematopoietic progenitors because the first one was considered inadequate. Five patients had bone marrow harvest first and underwent apheresis later. Seven patients underwent apheresis first and had bone marrow harvest later. Most patients had advanced cancer and had been heavily pretreated at time of harvesting. The second harvest yielded an appropriate number of progenitors for a proportion of patients. Nine of 12 patients received both cryopreserved marrow and blood cells. Hematopoietic recovery in these patients was somewhat longer than in patients currently receiving blood cells as a support for high dose chemotherapy at our institution; however, except for 2 patient, neutrophil and platelet recovery was observed within a reasonable delay. We conclude that patients who have poor blood cell collection may benefit from bone marrow harvesting, and vice versa.

Adolescent↗

Phenotypic, molecular, and functional characterization of human peripheral blood CD34+/THY1+ cells.

A subset of mobilized CD34+ cells present in patient aphereses expresses Thy1 (CDw90). This population contains most long-term culture initiating cells, as assayed with a murine stromal cell line. It also contains a significant proportion of colony-forming unit granulocyte macrophage, but very few burst-forming unit erythroid. The limited differentiation towards the erythroid lineage is further confirmed by the absence of GATA-1 mRNA in the CD34+/Thy1+ subset, and by the low level of c-kit expression. The CD34+/Thy1+ subset appears phenotypically and functionally heterogeneous, a finding consistent with its high representation, compared to phenotypes such as CD34+/CD38-. Therefore, while at least some of CD34+/Thy1+ cells may be infectable by retroviral vectors, as shown by the presence of a transcript for the receptor for murine amphotropic retroviruses, the use of this selection strategy to specifically target human stem cells appears questionable.

Antigens, CD34↗