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[Abnormality of chromosome number 1 in 3 cases of acute transformation of chronic myeloid leukemia].

The authors report three cases of Ph1-positive chronic myelogenous leukemia (CML) with chromosome no 1 abnormalities. Such abnormalities have seldom been reported: three cases out of 42 in blast crisis and none of the 70 patients in the chronic phase in our series. In case no 1 a translocation: (t(1q;14q) was noted. In case no 2 the rearrangement was more complex: partial duplication of the long arm of chromosome no 1 and presence of a 21q+ corresponding to chromosome no 21 on which a part of the long arm of chromosome no 1 was transferred. In case no 3 a double translocation was noted between chromosomes no 1 and no 11, involving either the p or q arm. A review of the literature shows that abnormalities of chromosome no 1 are more frequent during the blast crisis that in the chronic phase of CML. Chromosome no 1 abnormalities are found in a number of myeloproliferative syndromes but even more frequently in solid tumors. The rearrangement sites are reviewed by the authors. Such rearrangements of chromosome no 1 may indicate an increased potential of malignancy.

Adult↗

Induction of apoptosis in childhood acute leukemia by chemotherapeutic agents: failure to detect evidence of apoptosis in vivo.

This study is designed to investigate whether apoptosis occurs in vivo in pediatric patients with acute leukemia during induction therapy. When patients with common acute lymphoblastic leukemia (cALL) and acute myeloblastic leukemia (AML) were treated with prednisolone (60 mg/m2/day, p.o. or i.v.) and etoposide (150 mg/m2/day, i.v.), respectively, the blast cell counts fell to below 30% and 5%, respectively, in 1 week. However, during this cytoreduction phase, neither morphologically apoptotic cells nor fragmentation of DNA derived from peripheral blast cells were detected at any preparations. On the other hand, cALL but not AML cells spontaneously undergo apoptosis following their culture in vitro. The addition of autologous serum instead of fetal calf serum substantially prevented apoptosis from occurring spontaneously in cALL cells. When cALL and AML cells freshly obtained from patients before therapy were treated in vitro with 10 mumol/l prednisolone and 20 micrograms/ml etoposide, respectively, these cells underwent apoptosis within 6 hours, as determined by a morphological and DNA fragmentation assay. These in vivo and in vitro findings suggest that, although anticancer drugs may induce apoptosis in vivo, these apoptotic cells cannot be detected due to their rapid removal from the circulation.

Adolescent↗

Pathobiology of lymphoid and myeloid blast crisis and management issues.

Despite recent improvements in the treatment of early-stage disease, the blastic phase of chronic myeloid leukemia (CML) remains a therapeutic challenge. For imatinib-naïve patients, imatinib provided encouraging hematologic and cytogenetic benefits; however, the vast majority of CML blast crisis cases today arise in patients already on imatinib-based therapy. Clonal evolution and duplication of the Philadelphia chromosome continue to be associated with blastic phase transformation, but recent studies have identified BCR/ABL kinase domain mutations in 30%-40% of blast crisis patients. This implies that BCR-ABL-targeted therapy might have influenced the molecular road map to blastic transformation. In this review, we will examine the effect of imatinib on primitive CML progenitors and how this might influence the pathophysiology of blast crisis. A rational framework for deciding how best to integrate stem cell transplantation, traditional chemotherapy, imatinib, and other BCR-ABL kinase inhibitors in the care of blast crisis patients will also be discussed.

Algorithms↗

Phase I study of mitoxantrone plus etoposide with multidrug blockade by SDZ PSC-833 in relapsed or refractory acute myelogenous leukemia.

PURPOSE: Expression of the multidrug resistance gene (MDR1) p170 protein is frequent in leukemic blasts from patients with relapsed acute myelogenous leukemia (AML). A phase I study using the nonimmunosuppressive MDR1 blocker SDZ PSC-833 (PSC) in combination with mitoxantrone (MITO) and etoposide (VP) was performed. PATIENTS AND METHODS: Starting doses (LVL0) of MITO (3.25 mg/m2/d on days 1 and 3 to 6) and VP (210 mg/m2/d on days 1 and 3 to 5) were 40% of the maximal-tolerated dose (MTD) from a prior study. A 1.5-mg/kg loading dose of PSC was followed by a 120-hour continuous infusion of 10 mg/kg/d on days 2 to 6. Blood samples for PSC, MITO, and VP pharmacokinetics (PK) were taken on days 1 and 3, and samples for MDR1 expression were taken on day 0. RESULTS: Severe mucositis developed in all patients at LVL0; therefore, MITO and VP doses were reduced to 2.5 and 170 mg/m2 (LVL-1) for the next seven patients, and this dose proved to be MTD. All LVL0 and three LVL-1 patients had transient elevations in the serum bilirubin level to > or = 4 mg/dL. Serum creatinine level increased to greater than 2 mg/dL in one case. There were no other grade 3 or 4 nonhematologic toxicities observed. The peripheral blood was cleared of leukemia in three LVL0 and four LVL-1 patients. The marrow was cleared of leukemic cells in one LVL0 and five LVL-1 patients, and a significant reduction in marrow leukemic infiltrate was observed in eight of 10. No patient achieved complete remission (CR), and all died of progressive disease (n = 8) or infection (n = 2). MDR1 expression was detected by fluorescent-activated cell sorter (FACS) analysis in five of seven cases. An elevated MDR1 mRNA level was detected by quantitative polymerase chain reaction (Q-PCR) in six of eight cases studied. Clearing of leukemia cells from the marrow occurred in four of six MDR1-positive and one of three MDR1-negative patients. Despite the fact that LVL0 doses had to be reduced due to toxicity, coadministration of PSC did not produce a consistent effect on MITO PK; however, it did repeatedly lead to increased levels of VP in the serum. CONCLUSION: We conclude that PSC-MITO-VP is a tolerable regimen with antileukemic activity. Addition of PSC necessitated a 66% reduction in MITO and VP doses from a prior study without PSC.

Antineoplastic Combined Chemotherapy Protocols↗

Effect of thrombopoietin on proliferation of blasts from patients with myelodysplastic syndromes.

Thrombopoietin (TPO), a major cytokine involved in megakaryocytopoiesis/thrombopoiesis, may be effective for treatment of the thrombocytopenia associated with myelodysplastic syndromes (MDS). However, it has been unclear whether TPO stimulates proliferation of MDS blasts, as observed in de novo acute myeloid leukemia. This study examined this concern. When marrow cells from 37 MDS cases were cultured with or without recombinant human PEGylated TPO, TPO increased the blast number (stimulation index > or =1.5) in 9 of 16 high-risk MDS cases (refractory anemia with excess blasts [RAEB] and RAEB in transformation) and 4 of 10 cases with MDS transformed to acute leukemia (MDS-AL), but none of 11 cases with low-risk MDS (RA and RA with ringed sideroblasts). When the cell cycle of cultured cells was determined by three-color flow cytometry, TPO activated the cell cycle of MDS cells (causing a decrease in G(0)-phase cells) in most of the cases whose blast number increased in response to TPO. Reverse transcriptase-polymerase chain reaction analysis detected TPO receptor messenger RNA in purified blasts from all six cases examined, irrespective of the response of their blasts to TPO in culture. Analysis of the patients' characteristics identified a high-serum lactate dehydrogenase (LDH) value as being associated with blast proliferation in high-risk MDS cases (p = 0.0036). We conclude that TPO stimulates in vitro proliferation of blasts from a fraction of MDS patients. High-risk MDS patients, especially those who have a high-serum LDH value, and MDS-AL patients should be monitored with particular care in clinical trials of TPO for MDS.

Adult↗

Potentiation of the stimulatory capacity of pokeweed mitogen via its binding to autologous erythrocytes.

The effect of human erythrocytes (E) on blastogenesis and immunoglobulin (Ig) production induced by pokeweed mitogen (PWM) in cultures of human peripheral blood mononuclear cells (PBMC) was investigated. The stimulation of PBMC with PWM was markedly enhanced in the presence of E, and PWM bound to E, followed by thorough washing (E-PWM), was even more effective in inducing blast cell formation and Ig production. Blast cell responses after stimulation with E-PWM were on average two times higher than those seen after stimulation with comparable dilutions of fluid-phase PWM. The PWM that remained in solution after incubation with E (Sup E-PWM) had little mitogenic capacity and inhibited the blast cell response induced by fluid-phase PWM. Transwell culture experiments demonstrated that the enhancement of the blast cell response of PBMC by E-PWM could be induced by PWM that was released from E-PWM, whereas the enhancement of Ig production was found to be dependent on the presence of PWM on E. Both for blast cell formation and Ig production, it was found that the enhanced stimulation with E-PWM depended on the presence of monocytes.

Erythrocytes↗

Mutations of the ras protooncogenes in chronic myelogenous leukemia: a high frequency of ras mutations in bcr/abl rearrangement-negative chronic myelogenous leukemia.

Seventy cases of chronic myelogenous leukemia (CML) were analyzed for the presence of ras mutations using polymerase chain reaction (PCR), oligonucleotide hybridization, and direct PCR sequencing. All cases had preceding cytogenetic and bcr rearrangement studies. Aberrant ras genes were detected in none of 39 patients with Philadelphia (Ph) chromosome or bcr/abl rearrangement positive chronic-phase CML and in only 1 of 18 patients in blast crisis, suggesting that ras mutations have little or no role in initiation or progression of common CML. Seven of 13, or 54% of patients with bcr/abl rearrangement negative chronic phase CML (atypical CML) harbored mutations in ras, however. This high incidence of ras mutations, together with the absence of bcr/abl rearrangement, provides evidence that atypical CML is an entity that is molecularly distinct from common CML. Moreover, the clinical characteristics and the high frequency of ras mutations suggest that atypical CML may constitute a subset of the myelodysplastic syndrome and may be best classified as a variant of chronic myelomonocytic leukemia (CMML).

Base Sequence↗

ABL mutations in late chronic phase chronic myeloid leukemia patients with up-front cytogenetic resistance to imatinib are associated with a greater likelihood of progression to blast crisis and shorter survival: a study by the GIMEMA Working Party on Chronic Myeloid Leukemia.

PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered.

Adult↗

Central nervous system involvement at presentation in the chronic phase of chronic myelogenous leukemia in childhood.

With the advent of more effective chemotherapy an increasing incidence of central nervous system involvement in acute lymphocyte (ALL) and myelocytic leukemias (AML) and chronic myelocytic leukemia (CML) in blast crisis has become evident. Meningeal involvement in the chronic phase of CML is rare. We report two children whose initial presentation of Ph1 CML was in the central nervous system as documented by cytocentrifugation. Aggressive combination chemotherapy and cranial irradiation has resulted in prolonged survival without blastic transformation or further meningeal disease. An approach to children with CML is suggested.

Adolescent↗

P53 gene mutations in chronic myelogenous leukemia medullary and extramedullary blast crisis.

Molecular alterations of the P53 gene were investigated in 27 unselected patients with chronic myelogenous leukemia (CML) blast crisis. A rearrangement of the P53 gene was evident by Southern blotting in 3 cases, one of which also showed the same alteration in the chronic phase. Single strand conformation polymorphism and sequencing analysis showed point mutations in 4 blast crisis cases. Of interest, P53 point mutations were evident in all the 3 cases of extramedullary blast crisis examined and the same point mutation was found in the myeloblastoma tissues and in the subsequent peripheral blast cells. These data indicate that: a) P53 gene mutations occur in a significant but not a large number of CML acute phase cases; b) P53 gene point mutations seem to correlate strongly with the infrequent extramedullary presentation of the blast crisis; c) the presence of the same P53 gene point mutation in extramedullary and bone marrow blast cells confirms the common clonal origin of the two cellular populations.

Blast Crisis↗

A phase II study of prednimustine in acute non-lymphocytic leukemia, smouldering leukemia, and refractory anemia with excess blasts.

Prednimustine, an ester of chlorambucil and prednisolone, was evaluated for efficacy and toxicity in a selected group of leukemia patients with a poor prognosis. Disease subsets consisted of patients with acute non-lymphocytic leukemia (ANLL) over age 60; ANLL refractory to standard therapy; smouldering leukemia; and refractory anemia with excess blasts (RAEB). In agreement with previous studies, toxicity from Prednimustine was relatively mild, consisting primarily of infrequent myelosuppression, gastrointestinal side-effects, and mild hyperglycemia. This study did not, however, confirm previously reported remission rates in ANLL: in 41 evaluable patients only two complete remissions were achieved. Both occurred in the subset of patients with smouldering leukemia. We conclude that Prednimustine has limited activity in this patient population.

Acute Disease↗

Differential expression of cell activation markers after stimulation of resting human B lymphocytes.

The interaction of antigen with surface Ig receptors initiates a complex process by which resting B lymphocytes are activated. In this study, small resting B lymphocytes were isolated by countercurrent elutriation of tonsillar B lymphocytes and stimulated with a range of concentrations of anti-mu and B cell growth factor (BCGF). The subsequent expression of two glycoproteins known to be absent from resting B lymphocytes but present on activated cells were analyzed with the monoclonal antibodies 4F2 and 5E9. The antigen recognized by the 4F2 monoclonal was expressed early in the G1 phase of the cell cycle and correlated with blast transformation; this was demonstrated by stimulating resting B cells with a low concentration of anti-mu sufficient for cellular activation but not proliferation. The 5E9-defined antigen was not present unless the B cells were stimulated with a higher concentration of anti-mu or a BCGF was added to the low concentration of anti-mu. The addition of hydroxyurea to culture blocked the entrance of stimulated B cells into S phase but did not interfere with the expression of either 4F2 or 5E9. Thus, whereas the monoclonal antibody 4F2 recognized cells in early G1, 5E9 recognized cells in late G1. By double immunofluorescence staining with propidium iodide and either 4F2 or 5E9, all cells in S, G2, and M phases were demonstrated to be both 4F2- and 5E9-positive. The monoclonal antibodies 4F2 and 5E9 can be used to distinguish an activated from a resting human B lymphocyte and to delineate sequential steps in the activation process.

Adolescent↗

Clinicopathological evolution and multilineage involvement in erythroleukemia: report of a case.

Results of sequential chromosome and cytologic studies in a patient with erythroleukemia (EL) by FAB criteria are described here. Major karyotype aberrations (MAKA) as well as normal karyotypes were detected at presentation, when the patient showed erythroid hyperplasia with moderate leftward shift of erythropoiesis and trilineage myelodysplasia, a picture suggestive of multilineage involvement. Following conventional induction therapy, the patient entered a myelodysplastic phase (MDS) with the features of refractory anemia with excess of blasts and subsequently relapsed with classical EL with maturation arrest of erythroblasts. Chromosome studies revealed a 46, XY karyotype in the MDS phase and only MAKA at leukemia relapse. These findings provide further evidence of a multistep cytogenetic and clinicopathological evolution of EL. Concomitant cytogenetic and morphologic studies in this patient seem to suggest the presence of chromosomally abnormal erythroblasts and confirm the existence of a association between MAKA and maturation arrest of erythroblasts.

Adult↗

Inherited pericentric inversion of chromosome 16 in chronic phase of chronic myeloid leukaemia.

The simultaneous occurrence of two specific acquired chromosomal abnormalities in chronic or acute leukaemias is rare. Inherited chromosomal abnormalities are also rare events in the general population. In chronic myeloid leukaemia (CML), characterised by the t(9;22)(q34;q11), the inv(16)(p13q22) has been described associated with the acceleration of disease or onset of blast crisis. We report on a patient with chronic phase of CML and both acquired t(9;22)(q34;q11) and inherited inv(16)(p13q22), who obtained a complete remission of the disease after bone marrow transplant. Therefore, it is worth to comment that an additional chromosomal abnormality in disease does not obligatory mean transformation of the disease to a more aggressive form, since chromosomal abnormalities are also seen in normal individuals.

Adult↗

High-dose cytosine arabinoside: treatment and cellular pharmacology of chronic myelogenous leukemia blast crisis.

Twenty-one patients with chronic myelogenous leukemia (CML) in blastic transformation underwent 22 remission induction attempts with high-dose cytosine arabinoside (ara-C), administered as a two-hour infusion of 3 g/m2 for six to 12 doses. Ara-C doses were administered every 12 hours in 15 patients and every six to ten hours in six patients. Median patient age was 35 years (range, 20 to 62). The median duration of benign phase was 25 months (range, 0 to 167). Morphology of blast crisis blast cells was myeloid in 15 patients and lymphoid in six. Five patients achieved complete remission (CR), three had partial remission (PR), and one had hematologic improvement, for an overall response rate of 41%. Median remission duration was 2.5 months (range, 0.5 to 6 months). Survival duration was 6 months for responding patients and 1.5 months for those with resistant disease. The response rate was similar for patients with myeloid and lymphoid blast crisis (31% v 50%, respectively). The response rate was significantly higher for patients whose benign phase was less than 1 year (75% v 21%, P = .05) and who had prolonged marrow aplasia after ara-C (86% v 27%, P = .05). Myelosuppression was the major dose-limiting toxicity, and cerebellar toxicity occurred in two patients. Intracellular ara-C 5'-triphosphate (ara-CTP) levels were similar in blood and bone marrow leukemic cells and were slightly greater in the cells of responding patients compared to those with resistant disease. We conclude that high-dose ara-C is an effective regimen for CML blast crisis, resulting in a substantial response rate but modest remission duration. Its combination with other agents may further improve the prognosis of patients with this resistant disease.

Adult↗

[Analysis of DNA contents in hematological malignant cells using whole blood lysis method].

The experiments have been undertaken whether DNA contents could be measured using whole blood lysis method by FACScan. Cell population in the phases of G1, S and G2 + M were well analyzed, when we used 3 x 10(6) cells lysed with 0.1% Triton X-100 in 1 ml of phosphate buffered saline, staining with 30 micrograms/ml of propidium iodide (PI) within 30 min after staining with PI. We have further developed cell cycle analysis for cells bearing lineage specific antigens recognized with FITC-conjugated monoclonal antibodies using two color analysis. When we fixed cells with 50% ice-cold ethanol after staining cells with FITC-conjugated antibodies, positive population ratio in these cells have been unchanged before and after fixing for CD3, CD4, CD5, CD8. CD10, CD19, CD14, CD33, and HLA-DR, but CD7 positive cells were markedly decreased after fixing. Using this method, CD41 positive leukemia cells have 3.4% in S phase and 6.8% in G2 + M phase, while CD41 negative cells have 1.8% in S phase and 2.0% in G2 + M phase in a patient with AML: M7, resulting leukemia cells were rich in S phase and G2 + M phase. The similar results were obtained in patients with AML:M2 using CD33 antibodies. During the clinical course, the changes of the blast numbers were well-correlated with changes of S-phase proportion in the patient with AML:M2. Among 47 patients with hematological malignancies in our hospital tested here, only 2 cases with 4.3% of total patients showed to have aneuploidy in malignant cells. One is a patient with non-Hodgkin lymphoma, the other is myelodysplastic syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Electrofocusing pattern of fucosyltransferase activity in human leukemic cells.

Fucosyltransferase (FT) activity of normal lymphocytes, normal granulocytes, and various types of human leukemic cells and electrofocusing pattern of FT activity in human leukemic cells and normal lymphocytes were examined using asialofetuin as an acceptor. Levels of FT activity in normal lymphocytes were higher than those of normal granulocytes in which FT activity was almost undetectable. The FT activity was higher in blast cells of acute myeloblastic leukemia and chronic myelogenous leukemia in blast crisis than in blast cells of acute lymphoblastic leukemia and the chronic phase of chronic myelogenous leukemia. The level of FT activity was lower in cells of chronic lymphocytic leukemia than that of normal lymphocytes, but it was higher than that of normal granulocytes. Three main isoelectric forms of FT in leukemic blast cells were identified by isoelectrofocusing, and they each had a characteristic focusing point: around pH 4.5 (peak 1); pH 4.9 (peak 2); and pH 5.2 (peak 3). In blast cells of myeloid leukemia, the activity of peak 3 was markedly higher than those of peaks 1 and 2. In blast cells of lymphoid leukemia, the activity of peak 3 was also the highest, but the activity of peak 2 was higher than that in myeloid blast cells. In normal lymphocytes, the major isoelectric form of FT was focused at around pH 4.9 and peak 3 was undetectable. These results indicated apparent differences not only in FT activity but also in isoelectric forms of FT between myeloid leukemic cells and lymphoid leukemic cells.

Blast Crisis↗

A nuclear antigen associated with cell proliferation and blast transformation.

A nuclear antigen associated with cell proliferation (proliferating cell nuclear antigen-PCNA) and blast transformation is recognized by autoantibodies in the sera of some patients with systemic lupus erythematosus. This autoantibody is a precipitating antibody and also reacts in immunofluorescence, staining the nucleoplasm of proliferating and blast-transformed cells. The autoantibody was used as a reagent to determine the distribution of PCNA in a synchronized continuous B lymphoid cell line (WiL-2) and in mitogen-induced blast-transformed lymphocytes. In WiL-2 cells, PCNA was detected as speckled nucleoplasmic staining in G1, S, and G2 phases of the cell cycle. In addition, during late G1 and early S phases, PCNA was also detected in the nucleolus. During mitogen-induced blast transformation of lymphocytes, PCNA was noticed in the nucleolus before the initiation of DNA synthesis and later became nucleoplasmic with disappearance of nucleolar staining. These studies demonstrate that the relationship of PCNA to proliferation and blast transformation may be associated with events related to DNA synthesis in these cells.

Animals↗