asta-z-7557 and Leukemia--Myeloid--Acute

Glufosfamide (beta-D-glucosyl-ifosfamide mustard) is a new agent for cancer chemotherapy. Its pharmacology is similar to commonly used oxazaphosphorines, but it does not require activation by hepatic cytochrome P-450 and preclinically demonstrates lower nephrotoxicity and myelosuppression than ifosfamide. The aim of the study was a comparison of the drug resistance profiles of glufosfamide and other oxazaphosphorines in childhood acute leukemias. Leukemic cells, taken from children with ALL on diagnosis (n = 41), ALL on relapse (n = 12) and AML on diagnosis (n = 13) were analyzed by means of the MTT assay. The following drugs were tested: glufosfamide (GLU), 4-HOO-ifosfamide (IFO), 4-HOO-cyclophosphamide (CYC) and mafosfamide cyclohexylamine salt (MAF). In the group of initial ALL samples median cytotoxicity values for GLU, IFO, CYC and MAF were 15.5, 33.8, 15.7 and 7.8 microM, respectively. In comparison with initial ALL samples, the relative resistance for GLU and IFO in relapsed ALL samples was 1.9 (p = 0.049) and 1.3 (ns), and in initial AML samples 31 (p < 0.001) and 5 (p = 0.001), respectively. All oxazaphosphorines presented highly significant cross-resistance. Glufosfamide presented high activity against lymphoblasts both on diagnosis and on relapse.

Topics: Adolescent; Child; Child, Preschool; Cyclophosphamide; Female; Glucose; Humans; Ifosfamide; In Vitro Techniques; Infant; Leukemia, Myeloid, Acute; Male; Phosphoramide Mustards; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Tumor Cells, Cultured

Clonal chromosome aberrations observed in patients who have relapsed after autologous bone marrow transplantation (ABMT) are usually related to the cytogenetic abnormalities observed at diagnosis. In order to assess this relationship, we evaluated 30 acute non-lymphocytic leukemia (ANLL) patients who underwent ABMT at out institution and had evaluable serial cytogenetic studies before and after ABMT. Seventeen patients (57%) showed no chromosome aberrations after ABMT in any of the studies performed, while 13 patients (43%) carried abnormalities. In eight out of 30 patients (27%0 the abnormal karyotype after ABMT was associated with hematologic relapse. The cytogenetic abnormalities were: (1) the same as at diagnosis without additional abnormalities in five patients; (2) the same as at diagnosis but with additional abnormalities in three patients. In one patient a different karyotype from that of diagnosis was detected and a myelodysplastic syndrome was clinically evaluable. Furthermore, occasional and single cell chromosome abnormalities were observed in four patients (13%), none of whom relapsed. The new and additional clonal cytogenetic abnormalities observed after ABMT were found in eight patients (27%), suggesting that this event may not be so frequent, that is presumably associated regimen. The re-appearance of the chromosome aberrations after ABMT and the relationship with the risk of relapse are discussed.

Topics: Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Purging; Bone Marrow Transplantation; Busulfan; Chromosome Aberrations; Chromosomes, Human; Clone Cells; Cyclophosphamide; DNA Damage; Female; Humans; Karyotyping; Leukemia, Myeloid, Acute; Male; Myelodysplastic Syndromes; Neoplasm, Residual; Neoplastic Stem Cells; Recurrence; Retrospective Studies; Risk Factors; Transplantation Conditioning; Transplantation, Autologous

The authors report their experience with the ASTA Z 7557, a derivative of cyclophosphamide, for the in vitro treatment of leukemic bone marrows. They determined the sensitivity of human leukemic progenitors (CFU-L, n = 9) and normal progenitors studied in semi-solid media cultures (CFU-GM, n = 37; BFU-e, n = 11) and in long term marrow culture (pré-CFU-GM n = 41). Data establish: The inhibition of the in vitro proliferation of CFU-L by ASTA Z 7557. The similar sensitivity of CFU-L and normal CFU-GM. The respect, at doses toxic on CFU-L and CFU-GM, of more primitive stem cells, capable of self-renewing and the existence of correlation between the intensiveness of treatment and the regeneration capacity of CFU-GM; therefore, they defined a maximum tolerable dose which spares 5 +/- 5% CFU-GM (DL 95) after treatment. The existence of a wide range susceptibility from patient to patient which requires the determination of the DL 95 for each individual patient.

Topics: Bone Marrow; Cells, Cultured; Cyclophosphamide; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid, Acute; Time Factors; Tumor Stem Cell Assay

The in vitro treatment of leukemic bone marrows, collected during complete remission, aims at eliminating residual blast cells prior to freezing and preservation, while sparing normal hematopoietic stem cells. We report our experience on the activity of ASTA Z 7557 on human leukemic (CFU-L) and normal hematopoietic stem cells. The sensitivity of human leukemic and normal progenitor cells (CFU-c), detected in semi-solid media cultures, is similar. However, pre-CFUc progenitors detected in long term marrow cultures are much less sensitive to ASTA Z 7557. Therefore autologous bone marrow transplantation can successfully be done with pretreated marrows containing 5 +/- 5% residual CFUc. The wide range of stem cells sensitivity to ASTA Z 7557 justify the predetermination of the optimal dose of drug for incubation prior to marrow collection for each individual patient. Our preliminary clinical experience is exposed.

Topics: Bone Marrow Transplantation; Cells, Cultured; Cyclophosphamide; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid, Acute; Neoplastic Stem Cells

The contamination of autologous marrow with clonogenic tumor cells has been the main argument against ABMT in acute leukemia. In a preclinical study we evaluated an active cyclophosphamide derivative named "ASTA Z 7557". We observed that the toxic effect of this drug on CFU-GM growth was dependent on nucleated cell concentration as well as on red blood cell contamination. The potency of the drug was in close relationship with the incubation temperature. The growth of leukemic CFU was inhibited with an ASTA Z dose higher than 30 micrograms/ml. In our system, beyond 40 micrograms/ml more than 95% of committed stem cells are destroyed. Fifteen patients had autotransplant because of AML for 10 patients and because of ALL for 5 patients (4 patients were grafted in relapse and 11 patients in remission). We demonstrated that the marrow take was possible although the inoculum is CFU-GM depleted. Five of the 10 AML patients are alive and remain disease-free at 45+, 65+, 190+, 345+ and 570+ days from ABMT without any maintenance treatment. Four of the 5 ALL patients are alive, three of them in complete remission (40+, 110+, 250+ days). The number of patients reported in this clinical study was relatively small and more cases should be evaluated to be conclusive. Nevertheless the feasibility of chemopurified ABMT was demonstrated.

Topics: Adult; Bone Marrow Transplantation; Cell Division; Cell Separation; Child; Child, Preschool; Colony-Forming Units Assay; Cyclophosphamide; Drug Evaluation; Female; Hematopoietic Stem Cells; Humans; Leukemia, Lymphoid; Leukemia, Myeloid, Acute; Male; Neoplastic Stem Cells; Stem Cells; Transplantation, Autologous

ASTA-Z-7557, an in vitro active metabolite of cyclophosphamide, has recently been introduced to purge autologous bone marrow grafts of patients with AML. The rationale of this approach assumes a relatively higher sensitivity of leukemic cells to the drug as compared to that of normal marrow precursors. We have investigated in direct comparison the sensitivity to ASTA-Z-7557 of normal bone marrow progenitors (GM-CFC and BFU-E) and clonogenic leukemic cells (L-CFC). Normal bone marrow cells and purified leukemic blast cells were exposed to varying concentrations of the drug. Dose-response relationships did not indicate a selective cytotoxic susceptibility of L-CFC to ASTA-Z-7557. The recovery of bone marrow precursors following exposure to ASTA-Z-7557 depended on the cell concentration during exposure and was higher for 2 X 10(7) cells/ml than for 1 X 10(6)/ml. To mimic minimal residual leukemia cell mixtures of 95% irradiated normal bone marrow cells with 5% leukemic blast cells were exposed to ASTA-Z-7557. In this mixture killing of L-CFC was largely decreased. These data suggest that in vitro incubation of autologous bone marrow grafts of patients with minimal residual leukemia with ASTA-Z-7557 might not offer a therapeutic advantage.

Topics: Cell Survival; Cells, Cultured; Cyclophosphamide; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid, Acute

Topics: Cells, Cultured; Cyclophosphamide; Dose-Response Relationship, Drug; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid, Acute