Bcl-2蛋白在成人急性白血病表达的临床意义

目的:检测Bcl-2蛋白在不同阶段成人急性白血病的表达分布,分析Bcl-2蛋白表达是否可以作为预测化疗反应的指标。方法:选择成人急性白血病患者骨髓标本72例,分3组:初治组18例,完全缓解(CR)组38例,复发组16例。正常对照组6例。以流式细胞仪和单克隆抗体检测Bcl-2蛋白表达,进行统计学分析。结果:①Bcl-2蛋白在初治组、CR组和复发组表达率分别为11.11%、18.42%、62.50%。复发组表达率显著高于初治组和CR组(均P<0.01),初治组和CR组表达率差异无统计学意义(P>0.05);②Bcl-2在急性髓细胞白血病和急性淋巴细胞白血病表达率分别是24.07%(13/54)和33.33%(6/18);两组差异无统计学意义(P>0.05);③Bcl-2蛋白表达阳性组与阴性组CR率分别是36.84%和77.36%(P<0.01)。结论:Bcl-2蛋白在成人急性白血病复发组高表达并且与CR率低相关。     

Predominance of functional multidrug resistance (MDR-1) phenotype in CD34+ acute myeloid leukemia cells

The expression of the MDR-1-encoded P-170 glycoprotein (P-170) associated with clinical multidrug resistance (MDR) was investigated in 52 consecutive patients with untreated acute myeloid leukemia (AML). P- 170 expression was analyzed in correlation with CD34 expression and clinical response. Thirty of 52 patients expressed P-170 (58%). Eight of 30 P-170+ as compared with 16 of 22 P-170- patients achieved a complete remission (CR) (27% v 73%, P = .003). In 21 of 30 P-170+ patients, expression of the CD34 antigen was observed in greater than 10% of the blast cells, as compared with 14 of 22 P-170- patients (70% v 64%, P > .05). The CR rate of CD34+ and CD34- patients was 31% and 76%, respectively (P = .006). In AMLs that simultaneously expressed both P-170 and CD34, the CR rate was worse as compared with those negative for P-170 and CD34 (5% v 63%, P = .004). In 12 patients (8 P- 170+, 4 P-170-) CD34 and P-170 expression were further characterized by double fluorescence studies. It was shown that P-170+ cells were largely, but not exclusively, restricted to the CD34+ cell population. For the 8 P-170+ AML samples, the median ratio of P-170+/P-170- in CD34+ cells was 4.845 (range, 0.60 to 25.00) as compared with 0.135 (range, 0.02 to 0.67) in CD34- cells. In these 12 AML samples, the presence of functional resistance as defined by reduced daunorubicin accumulation was evaluated in CD34+ and CD34- AML cells. In 8 of 8 P- 170+ patients, intracellular daunorubicin accumulation in CD34+ AML blast cells was lower than in CD34- cells, and it increased after cyclosporin addition. No difference of intracellular daunorubicin accumulation was observed between CD34+ and CD34- AML cells of 4 P-170- patients. These data indicate that P-170 expression in AML with a heterogeneous CD34+ phenotype seems predominantly present in CD34+ AML blast cells.     

Multidrug resistance of acute leukemia and a strategy to overcome it

A representative cause of multidrug resistance (MDR) is expression of the MDR gene (mdr1) and its product P-glycoprotein (P-gp). The function of P-gp is thought to be the extrusion of anticancer drugs from the cell against a concentration gradient. In acute myelogenous leukemia (AML), P-gp expression in leukemic blast cells at initial presentation has been reported to be 20% to 40%. The remission rate of acute leukemia patients is significantly lower in P-gp+ patients than in P-gp- patients. A significantly shorter survival and relapse-free survival in P-gp+ AML patients compared with P-gp- patients has been reported. Intracellular daunorubicin/Rhodamine123 content in P-gp+ leukemic blast cells is significantly lower than in P-gp- leukemic blast cells. By using a leukemic blast colony assay, lowered sensitivity to the anticancer drug was revealed not only in leukemic blast cells but also in leukemic progenitors. One method to overcome MDR with a possibility of clinical application is to use drugs that interfere with the function of P-gp. The addition of MS-209 in vitro as an MDR-reversing agent significantly enhanced the intracellular daunorubicin/Rhodamine 123 accumulation and the retention of P-gp+ leukemic blast cells to a level similar to that of P-gp- blast cells. Recent clinical trials using MDR-reversing agents have demonstrated some encouraging results in P-gp+ patients but not in P-gp- patients.     

MDR1 gene-related clonal selection and P-glycoprotein function and expression in relapsed or refractory acute myeloid leukemia

The expression of P-glycoprotein (P-gp), encoded by the MDR1 gene, is an independent adverse prognostic factor for response and survival in de novo acute myeloid leukemia (AML). Little is known about MDR1 expression during the development of disease. The present study investigated whether MDR1 gene- related clonal selection occurs in the development from diagnosis to relapsed AML, using a genetic polymorphism of the MDR1 gene at position 2677. Expression and function of P-gp were studied using monoclonal antibodies MRK16 and UIC2 and the Rhodamine 123 retention assay with or without PSC 833. No difference was found in the levels of P-gp function and expression between diagnosis and relapse in purified paired blast samples from 30 patients with AML. Thirteen patients were homozygous for the genetic polymorphism of MDR1 (n = 7 for guanine, n = 6 for thymidine), whereas 17 patients were heterozygous (GT). In the heterozygous patients, no selective loss of one allele was observed at relapse. Homozygosity for the MDR1 gene (GG or TT) was associated with shorter relapse-free intervals (P =.002) and poor survival rates (P =.02), compared with heterozygous patients. No difference was found in P-gp expression or function in patients with AML with either of the allelic variants of the MDR1 gene. It was concluded that P-gp function or expression is not upregulated at relapse/refractory disease and expression of one of the allelic variants is not associated with altered P-gp expression or function in AML, consistent with the fact that MDR1 gene-related clonal selection does not occur when AML evolves to recurrent disease. (Blood. 2001;97:3605-3611)     

Clinical significance of P-glycoprotein expression and function for response to induction chemotherapy, relapse rate and overall survival in acute leukemia

BACKGROUND AND OBJECTIVES: A multidrug-resistance (MDR) phenotype mediated by P-glycoprotein (P-gp) contributes to chemotherapy failure in acute leukemia. However, the exact prognostic significance of this resistance mechanism is still unclear, mostly due to methodologic problems in P-gp detection. We therefore investigated, whether P-gp expression levels or functional P-gp activity better predict response to induction chemotherapy, relapse rate and overall survival in acute leukemia. DESIGN AND METHODS: We examined cell samples of 121 adults with de novo acute myeloid leukemia (AML) and 102 children with newly diagnosed acute lymphoblastic leukemia (ALL) for P-gp expression and functional P-gp activity by flow cytometry. P-gp function was determined by the rhodamine 123 (rh123)-efflux test (AML n=121, ALL n=102) and P-gp expression levels using the P-gp specific monoclonal antibodies (moabs) MRK-16 (AML n=51, ALL n=31), 4.E3 (AML n=35, ALL n=32), or UIC-2 (AML n=68, ALL n=50). We correlated our findings with the immunophenotype, FAB morphology, cytogenetics and clinical data of the examined patients. RESULTS: P-gp expression levels as detected by MRK-16 and 4.E3 were very low and did not differ between AML and ALL as estimated using relative fluorescence intensity (RFI) values and D-values by Kolmogorow-Smirnov (KS) statistics. For moab UIC-2, P-gp expression levels were higher in AML than in ALL. Within AML, moab UIC-2 mainly reacted with myelomonocytic-differentiated leukemic cells of the FAB M4/5 subtypes. No correlation between P-gp expression levels as detected by MRK-16, 4.E3 or UIC-2 and the response to induction chemotherapy or relapse rate, both in AML and ALL, was observed. However, a prognostic impact of P-gp expression levels on overall survival in AML was seen for moab MRK-16. Moreover, within AML, P-gp function was higher in immature blast cells as defined by immunophenotype and FAB morphology and correlated with response to induction chemotherapy, relapse rate, overall survival as well as cytogenetic risk groups. In ALL, the overall functional P-gp activity was lower than in AML and did not correlate with immunophenotypical subgroups, response to induction chemotherapy, relapse rate or overall survival. INTERPRETATION AND CONCLUSIONS: Our data demonstrate a prognostic impact of P-gp in AML but not ALL and indicate that the functional rh123-efflux assay should be preferred for flow-cytometric P-gp evaluation in acute leukemia compared with P-gp expression analysis by monoclonal antibodies.     

Predictable prognostic factor of CD56 expression in patients with acute myeloid leukemia with t(8:21) after high dose cytarabine or allogeneic hematopoietic stem cell transplantation

CD56 expression in acute myeloid leukemia (AML) has been associated with extramedullary leukemia and multidrug resistance, but its clinical and prognostic significance has not been clearly identified. This study examined CD56 expression in 37 adult de novo AML patients with t(8:21). CD56 was expressed in 25 cases (67.6%). Complete remission (CR) rates were similar in both groups (91.7% vs. 88.7%; P = 0.73), but the relapse rates differed considerably (60% vs. 25%; P = 0.02). The median duration of disease-free survival (DFS) was significantly shorter in the CD56+ (median, 12.2 +/- 6.4 months) than in the CD56- group (median, not reached) (P = 0.02). In addition, the median duration of survival differed significantly in the CD56+ group (median, 14.9 +/- 4.4 months) compared with the CD56- group (median, not reached) (P = 0.01). Of the fifteen transplanted patients who achieved CR, allogeneic HST was performed from their siblings. The median duration of DFS in the CD56+ patients was significantly shorter than the CD56- patients (median, 24.4 +/- 4.5 months vs. median, not reached; P = 0.02). We concluded that CD56 expression correlates to a reduced DFS and survival for AML patients with t(8:21), including those patients who underwent transplantation.     

Biologic characteristics of acute leukemia after myelodysplastic syndrome

Ten patients with acute leukemia after primary myelodysplastic syndrome (MDS-AL) were examined to clarify the biologic nature of the leukemic cells in comparison with that of de novo acute myelocytic leukemia (AML). The morphologic and cytochemical features of the leukemic cells from all these patients corresponded well to those of de novo AML, and they were diagnosed with MDS-AML. Phenotypically, the frequent expression of the lymphocyte activation antigens, CD25 and CD30, was characteristic in MDS-AML. The in vitro response of MDS-AML cells to various growth factors was similar to that of de novo AML cells. Transforming growth factor beta 1 (TGF beta 1) suppressed growth factor- dependent colony formation by normal bone marrow cells, MDS bone marrow cells, and de novo AML cells, but did not inhibit colony formation by MDS-AML cells. The number of TGF beta 1 high-affinity binding sites of MDS-AML samples (< 5 to 47 sites/cell) was markedly lower than that in de novo AML samples (120 to 221 sites/cell). Our results indicate that the reduced TGF beta 1 may represent disregulation of the proliferation system in MDS-AML cells. This is thought to occur during the MDS phase, and may be related to the poorer response shown to conventional chemotherapy of AML.     

急性髓性白血病178例患者的细胞遗传学特征

目的 探讨急性髓性白血病(AML)患者的细胞遗传学特征.方法 采用骨髓短期培养和G显带技术对178例AML患者进行染色体核型分析.结果 178例患者中,171例有足够可供分析的中期分裂象.171例患者异常克隆检出率74.9%.其中27例患者为骨髓增生异常综合征(MDS)继发AML,其异常克隆榆出率为92.6%,在其余144例原发AML中异常克隆检出率为71.5%,MDS继发AML异常克隆检出率明显高于原发AML患者.171例患者中预后良好核型占24.0%,预后中等核型占46.8%,预后不良核型占29.2%.在预后良好核型中以t(15;17)为多;在预后中等核型中以正常核型为主;在预后不良核型中以复杂异常核型为主,复杂核型的异常克隆中常含有-5/5q-、-7/7q-等具有不良预后的异常克隆.老年组75例患者中,预后良好、预后中等及预后不良核型分别为16.0%、48.0%及36.O%,年轻组96例患者中分别为30.2%、45.8%及24.0%.老年患者预后良好核型比例低于年轻患者.MDS继发AML患者预后不良核型比例及单体核型比例均高于原发AML患者(P值均<0.001).结论 t(15;17)、正常核型、复杂核型分别是AML最常见的预后良好核型、预后巾等核型及预后不良核型.MDS继发的AML及老年AML患者染色体核型预后不良.

Abstract：

Objective To explore the cytogenetic characteristics of acute myeloid leukemia(AML) patients.Methods The karyotype analysis was performed in 178 AML using the short-term culture of bone marrow cell and G-banding technique.Results Among the 178 patients,171 had enough metaphases for analysis and 128(74.9%)had clonal karyotypic abnormalities.Twenty-seven patients were secondary to myelodysplastic syndrome (MDS-AML),with 25 (92.6%) patients carrying clonal karyotypic abnormalities.Among the remaining 144 patients of de novo AML,103(71.5%)had clonal karyotypic abnormalities.The rate of abnormal clonal karyotype was higher in MDS-AML than that of de novo AML (P=0.021).Among the 171 patients,41(24.0%)were in favorable risk group,80(46.8%)in intermediate risk group and 50(29.2%)in adverse risk group.t(15;17)was the most common chromosomal aberration.The maiority intermediate risk chromosomal aberration was;normal karyotype.The most common cytogenetic abnormality among adverse group was a complex karyotype.Adverse cytogenetic aberrations,such as -5/5q-,-7/7q-,frequently occurred in conjunction with one another as part of a complex karyotype.Totally 75 patients were 60 years or older,among them,16.0%were in favorable risk group,48.0%in intermediate risk group and 36.0%in adverse risk group.Among 96 younger patients,30.2%were in favorable risk group.45.8%in intermediate risk group and 24.0%in adverse risk group.The rate of favorable risk chromosomal aberration was lower in elder patients than in younger(P=0.03 1).The rate of adverse risk chromosomal aberration and the rate of monosomal karyotype were higher in MDSAML than in de novo AML patients(P<0.001).Conclusions The most common favorable,intermediate and adverse chromosomal aberrations were t(15;17),normal karyotype and complex karyotype respectively.The karyotype was poor in MDS-AML and elder AML patients.     

Overexpression of the major vault transporter protein lung-resistance protein predicts treatment outcome in acute myeloid leukemia

The monoclonal antibody LRP56 recognizes a 110-kD major vault protein (lung-resistance protein [LRP]) overexpressed in several P-glycoprotein- negative (Pgp-), multidrug resistant tumor cell lines. To determine the frequency of LRP overexpression, its prognostic significance, and its relation to Pgp, we analyzed bone marrow specimens from 87 consecutive patients with acute leukemia. Diagnoses included de novo acute myeloid leukemia (AML; 21 patients), leukemia arising from an antecedent hematologic disorder or prior cytotoxic therapy (secondary AML; 27 patients), AML in relapse (29 patients), and blast phase of chronic myeloid leukemia (CML-BP; 10 patients). A granular cytoplasmic staining pattern was detected by immunocytochemistry in 32 (37%) cases, including 7 (33%) de novo AML, 13 (48%) secondary AML, 11 (38%) relapsed AML, and 1 of 10 CML-BP. Among 66 evaluable patients with AML, LRP overexpression was associated with an inferior response to induction chemotherapy (P = .0017). Remissions were achieved in 35% of LRP+ patients as compared with 68% of LRP- patients. Although Pgp adversely affected response in univariate analysis (P = .0414), only LRP had independent prognostic significance when compared in a logistic regression model (P = .0046). Differences in remission duration (P = .075) and overall survival (P = .058) approached significance only for LRP. Sequential specimens from remitting patients receiving treatment with the Pgp modulator cyclosporin-A showed emergence of the LRP phenotype despite a decrease or loss of Pgp at the time of treatment failure (P =.0304). Significant associations were observed between LRP and age greater than 55 years (P = .017), Pgp (P = .040), and prior treatment with mitoxantrone (P = .020) but not with CD34. These findings indicate that overexpression of the novel transporter protein LRP is an important predictor of treatment outcome in AML.     

P-glycoprotein (P-170) expression in acute leukemias

Multidrug resistance (MDR) is still a major obstacle to chemotherapy success in acute myeloid leukemia (AML) and to a less extent acute lymphoblastic leukemia (ALL). Recent studies have shown that the expression of certain gene products mediate the development of resistance to chemotherapeutic agents. The most well characterized of these genes is the multidrug resistance gene MDR-1. This study was planned to study the expression of P-glycoprotein/170 in patients with acute leukemia and the effect of Cyclosporin A (CSA) as a modulator of P-glycoprotein functional activity. The study was carried out on 20 patients with acute leukemia (14 AML cases and 6 ALL cases). In addition, 6 normal individuals served as a reference group. Flow cytometric analysis of P-gp/170 surface expression was performed using UIC-2 MoAb together with the functional assay using Rhodamine 123 (Rh 123) and Cyclosporin A as a modulator.P-gp/170 was expressed on the leukemic cells of 37.5% of relapsed patients (40.0% of AML and 33.3% of ALL cases), whereas 27.2% of de novo patients expressed P-gp/170 (33.3% of AML cases and 0% of ALL cases). The functional activity of MDR-1 gp was 71.4% in AML and 33.3% in ALL patients compared with16.6% in normal lymphocytes. From this study, it is clear that P-gp/170 is expressed to a higher degree in leukemic cells and this is greater in relapsed compared to de novo cases and more in AML than ALL blasts. Functional activity is a more sensitive predictor of chemoresistance than P-gp/170 surface expression.     

Comparison of acute myeloid leukemia occurring de novo or preceded by a myelodysplastic stage: Differences in cellular DNA content

The DNA content of bone marrow cells in patients with acute leukemia preceded by a myelodysplastic stage (MDS-AML) was compared to that in patients with de novo AML. We studied granulocytes, lymphocytes, monocytes, and blasts/promyelocytes from Feul-gen-stained bone marrow smears of 11 patients with de novo AML, ten patients with MDS-AML, and 13 apparently healthy controls. The mean amount of DNA per cell (DNA index; Dl) in each cell population was determined using a digital video-based imageanalyzing system (CAS-100). Analysis of variance (F test) showed a significant difference in the DNA content between de novo AML on one hand and MDS-AML and controls on the other as regards to blasts/promyelocytes (P < 0.01), lymphocytes (P < 0.05), and monocytes (P < 0.01), respectively. In three of 11 (27%) patients with de novo AML, a lower than normal limit Dl was found both in immature and mature bone marrow cells. Patients with MDS-AML had those of Dl values similar to normal controls. In consequence, a significantly reduced mean Dl was found in patients with de novo AML in blasts/promyelocytes (P < 0.01), and monocytes (P < 0.05) compared to both normal controls and MDS-AML. Together with data published separately, suggesting differences in granulocyte morphology, clonality, and HLA-DR expression, these data suggest biological differences between the two diseases. © 1993 Wiley-Liss, Inc.     

The value of the MDR1 reversal agent PSC-833 in addition to daunorubicin and cytarabine in the treatment of elderly patients with previously untreated acute myeloid leukemia (AML), in relation to MDR1 status at diagnosis

To determine whether MDR1 reversal by the addition of the P-glycoprotein (P-gp) inhibitor PSC-833 to standard induction chemotherapy would improve event-free survival (EFS), 419 untreated patients with acute myeloid leukemia (AML) aged 60 years and older were randomized to receive 2 induction cycles of daunorubicin and cytarabine with or without PSC-833. Patients in complete remission were then given 1 consolidation cycle without PSC-833. Neither complete response (CR) rate (54% versus 48%; P = .22), 5-year EFS (7% versus 8%; P = .53), disease-free survival (DFS; 13% versus 17%; P = .06) nor overall survival (OS; 10% in both arms; P = .52) were significantly improved in the PSC-833 arm. An integrated P-gp score (IPS) was determined based on P-gp function and P-gp expression in AML cells obtained prior to treatment. A higher IPS was associated with a significantly lower CR rate and worse EFS and OS. There was no significant interaction between IPS and treatment arm with respect to CR rate and survival, indicating also a lack of benefit of PSC-833 in P-gp-positive patients. The role of strategies aimed at inhibitory P-gp and other drug-resistance mechanisms continues to be defined in the treatment of patients with AML.     

Allogeneic blood stem cell and bone marrow transplantation for acute myelogenous leukemia and myelodysplasia: influence of stem cell source on outcome

We have compared the outcomes of 87 patients with acute myelogenous leukemia (AML) and myelodysplasia (MDS) receiving matched sibling transplants with stem cells from peripheral blood (blood cell transplant, BCT) or bone marrow (BMT). In good risk patients (AML in CR1) granulocytes recovered to 0.5 x 10(9)/l a median of 14 days after BCT compared with 19 days after BMT (P < 0.0001). For patients with poor risk disease (AML beyond CR1 and MDS) corresponding figures were 16 vs 26 days (P < 0.0001). Platelet recovery to 20 x 10(9)/l was also faster after BCT (good risk 12 vs 20 days, P < 0.0001; poor risk 17 vs 22 days, P = 0.04). Red cell transfusions were unaffected by cell source, but BCT recipients required less platelet transfusions (good risk 1 vs 5, P = 0.002; poor risk 5 vs 11, P = 0.004). Blood cell transplants resulted in more chronic GVHD (86% vs 48%, P = 0.005) and a significantly higher proportion of recipients with KPS of 80% or less (48% vs 5%, P = 0.004). Disease-free survival at 4 years was 23% for both groups of poor risk patients but outcome in good risk patients was better after BCT (93% vs 62%, P = 0.047) related mainly to less relapse. While disease-free survival may be better after BCT than BMT for AML in CR1, quality of life may be relatively impaired.     

Bone marrow vs extramedullary relapse of acute leukemia after allogeneic hematopoietic cell transplantation: risk factors and clinical course

A total of 118 consecutive adult patients with acute leukemia (78 AML, 36 ALL, and four acute mixed lineage leukemia) underwent allogeneic hematopoietic cell transplantation (HCT) after conditioning with BuCy (n=113) or a nonmyeloablative regimen of busulfan-fludarabine (n=5). After a median follow-up of 35.8 months (range, 6.4-91.0), 34 patients experienced at least one episode of leukemia relapse. Of 34 initial episodes, 14 (41%) occurred in extramedullary sites, with (n=8) or without (n=6) concomitant bone marrow involvement. The median time to relapse in the extramedullary sites was longer than that of relapse in bone marrow only (13.5 vs 6.1 months, P=0.046). Acute leukemia subtype and disease status at HCT showed an independent predictive value for overall relapse, as well as for extramedullary relapse with or without bone marrow involvement (Philadelphia chromosome positive acute leukemia vs low-risk AML, relative risk 22.68 (95% CI, 2.18-235.64); other than first CR vs first CR, relative risk 5.61 (95% CI, 1.80-17.51)), but not for bone marrow relapse. Our study suggests that there may be different pathogenetic mechanisms for bone marrow vs extramedullary relapse of acute leukemia after allogeneic HCT. The mode of relapse needs to be investigated in future reports of acute leukemia treated with allogeneic HCT.     

Dysplastic peripheral blood polymorphs link acute myeloblastic leukaemia in elderly to the myelodysplastic syndromes.

We studied dysplastic features in peripheral blood polymorphs from 80 patients with acute leukaemia. Thirty-seven patients with de novo acute myeloblastic leukaemia (AML) were compared to 26 patients with AML that had developed after a myelodysplastic phase (MDS-AML), and 17 cases of acute lymphoblastic leukaemia (ALL). Cytoplasmic hypogranulation in neutrophils, measured as a score value (G-score; normal range: 255-300), and the percentage of pelgeroid polymorphs (ppp; normal range: 0.5%) were studied retrospectively by reviewing the diagnostic peripheral blood smears. The mean G-score was decreased in MDS-AML (178 +/- 67.9), and in de novo AML (212 +/- 65.1), but not in ALL (275 +/- 24.3). When de novo AML patients were divided by age, the elderly (greater than 60 yr) had significantly (p = 0.0001) lower mean G-score than the younger (less than 45 yr) ones; 156 +/- 64.8 v 243 +/- 41.4. This age-related difference became accentuated when only patients with extreme hypogranulation (G-score less than 150) were studied. Elderly de novo AML patients also had significantly (p = 0.0057) higher mean ppp. By studying the degree of polymorph dysplasia in the peripheral blood, it seems possible to identify a subset of dysplastic elderly AML patients, who might have passed a (preleukaemic) MDS phase unnoticed.     

Autologous stem cell transplantation for therapy-related acute myeloid leukemia and myelodysplastic syndrome

We report the results of 65 patients with treatment-related myelodysplastic syndrome (MDS)/acute myelogenous leukemia (AML) who were transplanted from an autograft and reported to the EBMT. The median age was 39 years (range, 3-69), and stem cell source was bone marrow (n = 31), or peripheral blood progenitor cells (n = 30), or the combination of both (n = 4). The primary disease was solid tumors (n = 37), Hodgkin's disease (n = 13), non-Hodgkin's lymphoma (n = 10), acute lymphoblastic leukemia (n = 2) or myeloproliferative syndromes (n = 3). The types of MDS were as follows: RAEB (n = 1; 2%), RAEB-t (n = 3; 5%), or AML (n = 56; 87%). The median time between diagnosis and transplantation was 5 months (range, 3-86). The Kaplan-Meier estimates of the probability of 3-year overall and disease-free survival were 35% (95% CI: 21-49%) and 32% (95% CI: 18-45%), respectively. The median leukocyte engraftment was faster after transplantation with peripheral blood stem cells than with bone marrow: 12 (range, 9-26) vs 29 (range, 11-67) days (P<0.001). The cumulative incidence of relapse was 58% (95% CI: 44-72%) and of treatment-related mortality 12% (95% CI: 6-38%). Lower relapse rate was seen in patients transplanted in first complete remission (CR1 vs non-CR1: 3 years: 48 vs 89%; P = 0.05). Furthermore, age beyond 40 years resulted in a higher treatment-related mortality (47 vs 7%; P = 0.01). In a multivariate analysis, transplantation in CR1 age as well as their interaction influenced overall survival significantly. Autologous transplantation may cure a substantial number of patients with treatment-related MDS/AML, especially if they are in CR1 and of younger age.     

P-Glycoprotein Expression in Acute Myeloid Leukaemia Cells at Diagnosis: Its relationship to Daunorubicin or Idarubicin Induction Therapy and Survival; Malignancy

We investigated the expression of P-glycoprotein (P-gp) in 50 adults with de novo diagnosed acute myeloid leukaemia (AML) and the relationship between presence of P-gp in leukaemic cells and efficacy, as remission induction and survival rate, of two different anthracyclines, daunorubicin (DNR) and idarubicin (IDR). We found that 30 out of 50 patients (60%) were negative (Group 1) and 20 (40%) were positive (Group 2) for P-gp expression evaluated by mean of MRK16 MoAb using a cut-off of 10% positive cells. Thirty-five out of 50 patients (70%) obtained complete remission (CR); depending on P-gp expression, the CR rate was 80% for group 1 and 45% for group 2 (p < 0.005). The median duration of overall survival was 20 months for patients in Group 1 as compared with 10 months for patients of Group 2 (p < 0.005). Regarding the anthracycline used, no significant difference in CR was observed in patients of Group 1 (75% of CR with DNR vs. 90% with IDR); Group 2 obtained 40% of CR with DNR vs. 70% with IDR (p < 0.005). The median duration of overall survival (OS) with the two regimens was comparable in Group 1, while it was significantly longer in patients of Group 2 treated with IDR compared with DNR regimen (p < 0.005). These results confirm the prognostic value of P-gp expression in AML at first appearance and we suggest that idarubicin could be a valid anthracycline drug in the treatment of AML to be evaluated as potential drug of choice in patients with primary or drug-induced multidrug resistance.     

P-glycoprotein expression in adult acute myeloid leukemia: correlation with induction treatment outcome

Drug resistance has become a major cause of the treatment failure in patients with acute leukemia. P-glycoprotein (P-gp), which is associated with multidrug resistance (MDR) phenotype, has been reported to be an important predictor of the treatment outcome. The aim of this study was to analyze the value of P-gp expression in bone marrow cells as a predictor of the response to remission induction chemotherapy, as well as duration of remission in adult patients with newly diagnosed acute myeloid leukemia (AML). We examined the expression of P-gp in 31 patients using the monoclonal antibody UIC2. Direct immunofluorescent labeling was performed and samples were analyzed by flow cytomery. Kolmogorov-Smirnov test (D-value) was used to estimate UIC2 staining. A D > or = 0.3 for labeling of gated leukaemic blasts as compared to that of the isotypic control was defined positive (+) and compared to clinical data. P-gp expression was found in 14/31 (45.6%) patients, 17/31 (54.8%) of the samples were found P-gp negative(-). No correlation was found regarding age, sex and FAB subtype, altough 6/14 (43%) cases with more than 50% of cells having P-gp expression, were CD34+/CD7+. Complete remission rates were significantly lower in UIC2+ patients than in UIC2- cases (70% vs 35%, p < 0.01). Complete remission duration was also shorter in UIC2+ patients (6 vs 12.4 months). Our data indicate, that P-gp expression is a reliable marker of resistance to induction treatment in patients with de novo AML and can help to identify patients who may require alternative regimens designed to overcome therapy resistance.     

Prognostic importance of immunophenotyping in adults with acute myelocytic leukaemia: the significance of the stem-cell glycoprotein CD34 (My 10)

A series of 23 monoclonal antibodies reactive with normal lymphoid and myeloid cells at various stages of differentiation were used to characterize 96 adult patients with acute myelocytic leukaemia (AML), concentrating on the possible role the expression of these antigens may have in predicting response to intensive chemotherapy. Only the expression of CD34 (P = 0.008) and HLA-DR (P = 0.035) was significant in predicting response to therapy; patients with leukaemic cells expressing CD34 (My10) had a complete remission (CR) rate of 59% compared to 87% for those with blasts not expressing the antigen. In a multivariate analysis predicting for CR, the expression of CD34, the disease category (de novo AML versus secondary AML [SAML] or a history of antecedent haematological disorder [AHD]), and WBC were significant covariates. Adjusting for disease category and WBC, patients with CD34-positive AML were one-third as likely to enter CR as with those with disease not expressing the antigen (P = 0.066). Comparison of clinical characteristics between the 58 patients whose leukaemia expressed CD34 and the 33 which were CD34-negative found that patients with CD34-positive AML had a higher incidence of SAML and AHD, a lower WBC at diagnosis, and a more frequent incidence of chromosomal abnormalities involving chromosomes 5 and/or 7. Twenty-eight of these patients also had immunophenotyping performed at relapse. Patients who presented with CD34-positive AML, and entered remission, and then relapsed all recurred with CD34-positive leukaemia; there was no case of CD34-positive AML at diagnosis relapsing with CD34-negative disease. In addition, there were patients presenting with CD34-negative AML and then relapsing with CD34-positive AML. These results suggest that intensive cytoreductive therapy is ineffective against CD34-positive AML. Patients who present with CD34-positive AML may require different therapeutic approaches to completely eradicate their disease.     

Fludarabine, cytarabine, G-CSF and idarubicin (FLAG-IDA) for the treatment of poor-risk myelodysplastic syndromes and acute myeloid leukaemia

Nineteen patients with high-risk myelodysplastic syndrome (MDS)/acute myeloid leukaemia (AML) received fludarabine, cytarabine, granulocyte-colony stimulating factor (G-CSF), and idarubicin chemotherapy ( de novo MDS/MDS-AML, nine; relapsed/refractory MDS/AML, seven; therapy-related MDS, three). Median age was 44 years and median disease duration 10 months. 16/19 (84%) patients had abnormal cytogenetics with seven (37%) harbouring abnormalities of chromosome 7. 18/19 (94.7%) patients responded to FLAG-idarubicin with 12 (63%) achieving complete remission (CR) (<5% blasts and normal cytogenetics). 7/9 (78%) patients with de novo MDS/MDS-AML achieved CR compared to 5/10 (50%) with alternative diagnoses. Response was associated with age < 50 years, disease duration < 3 months, and cytogenetics other than abnormalities of chromosome 7. Haemopoietic regeneration was rapid in most patients and there were no toxic deaths. Nine patients received a second course of chemotherapy, three have proceeded to allogeneic bone marrow transplant and three to autologous blood stem cell/bone marrow transplantation. Follow-up is short (median 10 months). 12/19 (63%) patients remain alive and 5/12 (42%) have relapsed at a median 5 months following CR achievement. FLAG-idarubicin was well tolerated. High rates of morphological and cytogenetic remission, especially in de novo MDS, offer a window of opportunity for assessment of autologous BMT in this group of diseases where no treatment except alloBMT has led to prolongation of survival.