An unusual case of CD4+ CD7+ CD56+ acute leukemia with overlapping features of type 2 dendritic cell (DC2) and myeloid/NK cell precursor acute leukemia

Type 2 dendritic cell (DC2) acute leukemia has been recently described. We report here an unusual case of a 17-yr-old adolescent with overlapping features of DC2 and myeloid/NK cell precursor acute leukemia as defined by Suzuki et al. The patient presented with lymphadenopathy and hepatosplenomegaly without extranodal manifestations in skin or elsewhere. The morphologic, cytochemical and immunophenotypic features were compatible with those described in DC2 acute leukemia, with co-expression of CD4, CD56 and CD123 antigens. The novel markers BDCA-4 and BDCA-2 considered specific for DC2s were co-expressed. However, bright CD7 positivity along with a dim expression of CD33 (57%) and CD117 (27%) were also noted. Additionally, there was bright expression of NG2 monoclonal antibody 7.1, a frequent finding in myeloid/NK cell precursor acute leukemia. The interpretation of the immunophenotypic profile leads to the hypothesis on the existence of borderline cases between DC2 and myeloid/NK cell precursor acute leukemia. Still, other hypotheses can not be overlooked, such as the possibility for a kind of variant monoblastic leukemia or of another rare entity of acute unclassified leukemia.     

Zalypsis has in vitro activity in acute myeloid blasts and leukemic progenitor cells through the induction of a DNA damage response

Background

Although the majority of patients with acute myeloid leukemia initially respond to conventional chemotherapy, relapse is still the leading cause of death, probably because of the presence of leukemic stem cells that are insensitive to current therapies. We investigated the antileukemic activity and mechanism of action of zalypsis, a novel alkaloid of marine origin.

Design and Methods

The activity of zalypsis was studied in four acute myeloid leukemia cell lines and in freshly isolated blasts taken from patients with acute myeloid leukemia before they started therapy. Zalypsis-induced apoptosis of both malignant and normal cells was measured using flow cytometry techniques. Gene expression profiling and western blot studies were performed to assess the mechanism of action of the alkaloid.

Results

Zalypsis showed a very potent antileukemic activity in all the cell lines tested and potentiated the effect of conventional antileukemic drugs such as cytarabine, fludarabine and daunorubicin. Interestingly, zalypsis showed remarkable ex vivo potency, including activity against the most immature blast cells (CD34⁺ CD38⁻ Lin⁻) which include leukemic stem cells. Zalypsis-induced apoptosis was the result of an important deregulation of genes involved in the recognition of double-strand DNA breaks, such as Fanconi anemia genes and BRCA1, but also genes implicated in the repair of double-strand DNA breaks, such as RAD51 and RAD54. These gene findings were confirmed by an increase in several proteins involved in the pathway (pCHK1, pCHK2 and pH2AX).

Conclusions

The potent and selective antileukemic effect of zalypsis on DNA damage response mechanisms observed in acute myeloid leukemia cell lines and in patients’ samples provides the rationale for the investigation of this compound in clinical trials.     

An antecedent diagnosis of refractory anemia with excess blasts has no influence on mobilization of peripheral blood stem cells and hematopoietic recovery after autologous stem cell transplantation in acute myeloid leukemia

Several studies have reported data on factors influencing mobilization of peripheral blood stem cells (PBSC) in non-myeloid malignancies. On the contrary, data from patients with acute myeloid leukemia (AML) are very limited, in particular, as the impact of an antecedent diagnosis of refractory anemia with excess blasts (RAEB) on mobilization of PBSCs as well as hematopoietic recovery after autologous stem cell transplantation (ASCT) is concerned. We retrospectively analyzed a cohort of 150 consecutive AML patients in first complete remission in order to make a comparison between patients with de novo AML and secondary AML (s-AML) in terms of CD34 positive (CD34+) cells mobilization and number of leukapheresis needed to collect at least one single stem cell graft. Data concerning hematopoietic recovery after ASCT were also compared. The successful mobilization rate (>2 x 10(6) CD34+ cells/kg) was comparable between de novo AML patients (87%) and those with s-AML (76%), P:0.21. No statistically significant difference was found in terms of either median number of CD34+ cells collected (P:0.44) or CD34+ cells peak in peripheral blood (P:0.28). Both groups of patients needed a median of two apheresis (P:0.45) and no difference was found on the median number of CD34+ cells collected per single apheresis (P:0.59). Finally, neutrophil and platelet recovery after ASCT were comparable between the two groups. An antecedent diagnosis of RAEB has no impact on mobilization and collection of PBSCs in AML as well as on hematopoietic recovery after ASCT.     

High levels of CD34+CD38low/-CD123+ blasts are predictive of an adverse outcome in acute myeloid leukemia: a Groupe Ouest-Est des Leucemies Aigues et Maladies du Sang (GOELAMS) study

Background

Acute myeloid leukemias arise from a rare population of leukemic cells, known as leukemic stem cells, which initiate the disease and contribute to frequent relapses. Although the phenotype of these cells remains unclear in most patients, these cells are enriched within the CD34⁺CD38^low/− compartment expressing the interleukin-3 alpha chain receptor, CD123. The aim of this study was to determine the prognostic value of the percentage of blasts with the CD34⁺CD38^low/−CD123⁺ phenotype.

Design and Methods

The percentage of CD34⁺CD38^low/−CD123⁺ cells in the blast population was determined at diagnosis using flow cytometry. One hundred and eleven patients under 65 years of age with de novo acute myeloid leukemia and treated with intensive chemotherapy were retrospectively included in the study. Correlations with complete response, disease-free survival and overall survival were evaluated with univariate and multivariate analyses.

Results

A proportion of CD34⁺CD38^low/−CD123⁺ cells greater than 15% at diagnosis and an unfavorable karyotype were significantly correlated with a lack of complete response. By logistic regression analysis, a percentage of CD34⁺CD38^low/−CD123⁺ higher than 15% retained significance with an odds ratio of 0.33 (0.1–0.97; P=0.044). A greater than 1% population of CD34⁺CD38^low/−CD123⁺ cells negatively affected disease-free survival (0.9 versus 4.7 years; P<0.0001) and overall survival (1.25 years versus median not reached; P<0.0001). A greater than 1% population of CD34⁺CD38^low/−CD123⁺ cells retained prognostic significance for both parameters after multivariate analysis.

Conclusions

The percentage of CD34⁺CD38^low/−CD123⁺ leukemic cells at diagnosis was significantly correlated with response to treatment and survival. This prognostic marker might be easily adopted in clinical practice to rapidly identify patients at risk of treatment failure.     

CD7+CD56+双阳性急性髓系白血病临床生物学特征

目的：探讨CD7^＋CD56^＋急性髓系白血病（AML）的临床生物学意义。方法：对25例初治CD7^＋CD56^＋AML患者进行细胞学形态、免疫表型、多药耐药P糖蛋白（PgP）检测，临床观察、并常规采用HAE方案诱导治疗，判定疗效，并随机选择66例CD7^-CD56^-AML患者进行对照。结果：CD7^＋CD56^＋AML阳性率4．08％（25／612）。CD7^＋CD56^＋AML在FAB分型中以M0、M1、M5、M7多见。与CD7^-CD56^-AML组比较CD7^＋CD56^＋AML具有高血红蛋白含量（89．29：75．62g／L，P〈0．05），高表达PgP（78．26％：34．85％，P〈0．01）和CD34表达（72．00％：45．45％，P〈0．05）等特征；此外，CD7^＋CD56^＋AML患者中枢神经系统浸润现象明显（36．00％：3．27％，P〈0．01），CD7CD56共表达与年龄、性别、白细胞计数、血小板计数、及外周血幼稚细胞数无关，也不影响完全缓解率和无病生存时间（均P〉0．05）。结论：CD7^＋CD56^＋AML具有独特的临床生物学特征，较少贫血，高表达PgP和CD34，常伴有中枢神经系统浸润。     

Granulocyte colony-stimulating factor (G-CSF) mediated mobilization of leukemic cells in Philadelphia chromosome positive acute lymphoblastic leukemia expressing myeloid antigens (my+Ph+ALL)

The therapeutic benefit of G-CSF in the treatment of acute lymphoblastic leukemia has been well established. G-CSF has been used to shorten neutropenia induced by conventional dose cytotoxic chemotherapy and allogeneic bone marrow transplantation. Recently autologous peripheral blood progenitor cell transplantation has been explored to treat high-risk ALL. Several in vitro studies suggest that subpopulations of lymphoblasts express G-CSF receptors. Furthermore, enhanced growth of Ph⁺ ALL cells expressing myeloid antigens stimulated by G-CSF has been demonstrated in vitro. However, the clinical relevance of these findings has been questioned. We report a patient with my⁺Ph⁺ALL in whom the administration of G-CSF after high-dose Cytarabin and Mitoxantrone led to a significant mobilization of leukemic cells and contamination of the stem cell harvest during cytologic marrow remission. Am. J. Hematol. 58:330–333, 1998. © 1998 Wiley-Liss, Inc.     

Activation of autologous leukemia-specific T cells in acute myeloid leukemia: monocyte-derived dendritic cells cocultured with leukemic blasts compared with leukemia-derived dendritic cells

In acute myeloid leukemia (AML) blasts can be differentiated into dendritic cell (DC) like cells (AML-DC). These cells have a mature DC-like phenotype, are strong stimulators in mixed leukocyte reactions and can be used to generate leukemia-specific cytotoxic T cells. However, recent reports about naturally existing leukemic DC with immunoregulatory dysfunctions in peripheral blood of AML patients caused concerns about the use of AML-DC for therapeutic purposes. Systematic intra-individual comparisons between AML-DC and non-leukemic DC derived from monocytes (MoDC) in AML patients are missing. Thus, we investigated the ability to generate MoDC from peripheral blood of 17 AML patients in first remission and their functional integrity to stimulate leukemia-specific T cells by simple coculture with leukemic blasts. Phenotypic analysis of AML-DC and MoDC from the same individual patients revealed that MoDC exhibit a more homogenous mature DC phenotype. Additionally, functional analysis demonstrated the ability of remission MoDC to activate autologous leukemia-specific T cells in 11 of 12 patients, whereas AML-DC led to a specific T cell activation in four of eight patients. The presented findings might have impact on the design of further therapeutic studies using autologous antigen-presenting cells.     

Co-expression of CD30 ligand and interleukin 4 (IL-4) receptors by acute myeloid leukaemia blasts is associated with the expansion of IL-4-producing CD30+ normal T cells

CD30 ligand (CD30L), but not its cognate receptor CD30, is frequently expressed on acute myeloid leukaemia (AML) blasts. In the present study, we found that leukaemic blasts presenting surface CD30L displayed a characteristic cytokine-receptor pattern that makes them ideal targets for those cytokines usually produced by Th2-type cell subsets. In particular, even though a broad distribution of Th2 cytokine receptors by AML blasts was shown, we demonstrated the almost exclusive expression of interleukin 4 (IL-4) receptor (R), in the absence of its cognate cytokine, by CD30L+ AML. Furthermore, a number of Th2-associated markers, including CD30, IL-4 and GATA-3, were expressed by residual T cells derived from CD30L+ AML but not from CD30L- AML, in which the presence of the Th1-associated marker LAG-3 was documented in some cases. The production of IL-4 in the absence of interferon gamma (IFN-gamma) was also detected in CD3+/CD30+ T cells from CD30L+ AML. These results, along with the shift toward IL-4-producing specific T-cell clones observed in CD30L+ AML samples by enzyme-linked Immunospot (ELISpot) assay, were consistent with the hypothesis of a Th2 polarization taking place in T cells from CD30L+ AML. The notion that IL-4 was able to enhance in vitro proliferation of CD30L+/IL-4R+ purified leukaemic blasts suggests that the selective interaction of IL-4-producing CD30+ T cells with CD30L+ leukaemic progenitors may have a role in the progression of this particular AML subset.     

Inhibition of invariant chain expression in dendritic cells presenting endogenous antigens stimulates CD4+ T-cell responses and tumor immunity

Induction of potent and sustained antiviral or antitumor immunity is dependent on the efficient activation of CD8+ and CD4+ T cells. While dendritic cells constitute a powerful platform for stimulating cellular immunity, presentation of endogenous antigens by dendritic cells transfected with nucleic acid-encoded antigens favors the stimulation of CD8+ T cells over that of CD4+ T cells. A short incubation of mRNA-transfected dendritic cells with antisense oligonucleotides directed against the invariant chain enhances the presentation of mRNA-encoded class II epitopes and activation of CD4+ T-cell responses in vitro and in vivo. Immunization of mice with the antisense oligonucleotide-treated dendritic cells stimulates a more potent and longer lasting CD8+ cytotoxic T-cell (CTL) response and enhances the antitumor efficacy of dendritic cell-based tumor vaccination protocols. Transient inhibition of invariant chain expression represents a simple and general method to enhance the stimulation of CD4+ T-cell responses from endogenous antigens.     

CD1-reactive leukemic cells in bone marrow: presence of Langerhans cell marker on leukemic monocytic cells.

Langerhans cells originate in bone marrow and probably belong to the monocyte-macrophage lineage. CD1 is a specific marker of Langerhans cells. By immunofluorescence and immunoelectron microscopy, CD1a antigen and myeloid markers (CD11, CD13, CD14, CD15, CD33, HLA-DR) were studied in 53 cases of acute myeloid leukemias (AML) and 3 acute lymphoblastic leukemias (ALL). The 11 ANLL without monocytic component were CD1a negative. 2/5 of acute myelomonocytic leukemias (AML4) and 9/37 of acute monocytic leukemias (AML5) were positive. All 3 ALL were negative. No correlation was found between CD1a and myeloid markers. CD1a+ AML did not differ from CD1a- AML with regard to cytogenetics or response to therapy. The CD1a positive cells may originate from an abnormal proliferation of CD1a positive cells which are present in bone marrow and which may differentiate into Langerhans cell precursors.     

Circulating CD34+ cells: an adverse prognostic factor in the myelodysplastic syndromes.

As part of an epidemiological survey of myelodysplastic syndromes (MDS) in southern Tasmania, 62 MDS patients identified over a 2 year period were tested for the presence of CD34, the human progenitor cell antigen (HPCA), in their peripheral blood. The results were correlated with transformation to acute myeloid leukemia (AML) and patient survival, and CD34+ status was compared as a prognostic indicator with Bournemouth score, cytogenetics, and CFU-GM colony growth which were also assessed. Circulating CD34+ cells were found in 23 of the 62 MDS patients; 9 of the 23 patients with circulating CD34+ cells transformed to AML, as compared with none of the 39 CD34 negative patients (P less than 0.0001); and 11 of the 23 patients with circulating CD34+ cells were dead at the end of the 2 year period, as opposed to 6 of the 39 with no CD34+ cells (P less than 0.03). The Bournemouth score was also significantly associated with transformation to AML (P less than 0.0001) and poor survival (P less than 0.04). These were the only significant associations of the possible prognostic factors studied with either transformation or survival. In summary, the presence of circulating CD34+ cells was significantly associated with both progression to AML and poor survival and was found to be a better prognostic indicator than cytogenetics or CFU-GM colony growth.     

An immunophenotypic pre‐treatment predictor for poor response to induction chemotherapy in older acute myeloid leukaemia patients: blood frequency of CD34+ CD38low blasts

Many older patients with acute myeloid leukaemia (AML) that receive standard intensive chemotherapy fail to achieve complete remission (CR). Upfront identification of patients unlikely to benefit from standard induction chemotherapy would be important for exploration of novel therapies. This study evaluated if a flow cytometric assay measuring pre‐treatment CD34⁺ CD38^low blast frequency could predict therapeutic‐resistance in 736 AML patients entered into the UK National Cancer Research Institute AML16 trial. High peripheral blood CD34⁺ CD38^low blast frequency (>7% of leucocytes), present in 18% of assessable patients, conferred significantly reduced CR rates (38% vs. 76%, P < 0·0001) and poor survival, and was independently prognostic for all endpoints of treatment resistance by multivariate analysis.     

地西他滨治疗老年急性髓系白血病疗效及安全性分析

目的探讨以地西他滨为基础的化疗方案治疗老年急性髓系白血病(AML)的临床疗效及安全性。方法回顾性地分析2013年1月至2016年2月盐城市第三人民医院血液科收治的29例老年AML患者的临床资料,根据其是否使用地西他滨分为地西他滨组和传统方案组,对比评定疗效。结果地西他滨组和传统方案诱导后的完全缓解率分别为60.0%(6/10)和35.7%(5/14),差异有统计学意义(P0.05);同时两组的总生存期差异有统计学意义(44.9vs13.6个月,P0.05)。80.0%老年AML患者在使用以地西他滨为基础的化疗方案治疗过程出现不同程度的不良反应,仅30.0%的患者发生了Ⅲ~Ⅳ级不良反应,主要为中性粒细胞减少和血小板减少。结论地西他滨为基础的化疗方案有较高的缓解率,且可延长生存期。     

Donor lymphocyte infusions for relapse of chronic myeloid leukemia after allogeneic stem cell transplantation: prognostic significance of the dose of CD3+ and CD4+ lymphocytes

Between December 1993 and November 2001, 30 patients with chronic myeloid leukemia who relapsed after stem cell transplantation were studied. Seventeen patients were not treated before donor lymphocyte infusion (DLI), eight patients received interferon- (IFN-), and five underwent chemotherapy. The method of DLI was the bulk dose regimen. The median time between DLIs was 6 weeks. The median number of infusions was three; the median time from transplant to relapse was 17 months and from relapse to DLI 2 months. Eleven patients (37%) were in molecular/cytogenetic relapse, 14 (47%) in chronic phase, and five (16%) in accelerated or blastic phase. Seventeen patients (57%) developed acute graft-versus-host disease (GVHD). Chronic GVHD was observed in 15 of 24 (62%) patients. Four (13%) patients developed cytopenia after a median of 30 days. Nineteen (63%) patients achieved response, 15 of them developed GVHD. The response rate according to the disease phase was molecular or cytogenetic relapse: 91%, chronic phase: 57%, and accelerated or blastic phase: 20%. The median time to response was 6 months. Patients treated with IFN- or no treatment as well as those who were in molecular/cytogenetic relapse and those who received a CD3⁺ cell dose <1×10⁸/kg and CD4⁺ <8×10⁷/kg had better survival. We conclude that patients who receive lower doses of lymphocytes have better survival. In some patients IFN- seems to be a good choice to potentiate the graft-versus-leukemia (GVL) effect.     

Correlation of MDR1/P-170 expression with daunorubicin uptake and sensitivity of leukemic progenitors in acute myeloid leukemia.

Prior studies have shown that multidrug resistance gene products may be detected in acute myeloid leukemia (AML) cells, and are associated with poor response to therapy. We studied whether P-170 expression was associated with in vitro daunorubicin (DNR) accumulation and sensitivity of leukemic clonogenic cells (CFU-L) to DNR in 16 newly diagnosed AML samples. P-170 expression was assessed by indirect immunofluorescence using the monoclonal antibody MRK16. DNR cellular content was measured by flow cytometry after short incubation with increasing concentrations of DNR, and was not correlated with P-170 expression, although there was a trend for higher values in P-170-negative samples. The sensitivity of CFU-L was studied in a semisolid culture assay by calculating the dose of DNR inhibiting the growth of 90% of CFU-L (D90). The D90 was significantly higher in P-170-positive than in P-170-negative samples (mean = 1.68 +/- 0.42 microgram/ml versus 0.97 +/- 0.35 micrograms/ml respectively, p less than 0.005). Eight of 9 cases achieving complete remission (CR) after intensive chemotherapy were P-170-negative, whereas 7 of 7 nonresponders were P-170-positive (p less than 10(-5)). D90 was significantly lower for patients achieving CR than for those who did not achieve CR (1.12 +/- 0.55 micrograms/ml versus 1.59 +/- 0.37 micrograms/ml, p = 0.04). It is concluded that P-170 expression is correlated with in vitro resistance of clonogenic cells to DNR and may be one mechanism of resistance to chemotherapy.