Inhibition of EZH2 by chidamide exerts antileukemia activity and increases chemosensitivity through Smo/Gli-1 pathway in acute myeloid leukemia.

BACKGROUND: Epigenetic dysregulation plays important roles in leukemogenesis and the progression of acute myeloid leukemia (AML). Histone acetyltransferases (HATs) and histone deacetylases (HDACs) reciprocally regulate the acetylation and deacetylation of nuclear histones. Aberrant activation of HDACs results in uncontrolled proliferation and blockade of differentiation, and HDAC inhibition has been investigated as epigenetic therapeutic strategy against AML. METHODS: Cell growth was assessed with CCK-8 assay, and apoptosis was evaluated by flow cytometry in AML cell lines and CD45 + and CD34 + CD38- cells from patient samples after staining with Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI). EZH2 was silenced with short hairpin RNA (shRNA) or overexpressed by lentiviral transfection. Changes in signaling pathways were detected by western blotting. The effect of chidamide or EZH2-specific shRNA (shEZH2) in combination with adriamycin was studied in vivo in leukemia-bearing nude mouse models. RESULTS: In this study, we investigated the antileukemia effects of HDAC inhibitor chidamide and its combinatorial activity with cytotoxic agent adriamycin in AML cells. We demonstrated that chidamide suppressed the levels of EZH2, H3K27me3 and DNMT3A, exerted potential antileukemia activity and increased the sensitivity to adriamycin through disruption of Smo/Gli-1 pathway and downstream signaling target p-AKT in AML cells and stem/progenitor cells. In addition to decreasing the levels of H3K27me3 and DNMT3A, inhibition of EZH2 either pharmacologically by chidamide or genetically by shEZH2 suppressed the activity of Smo/Gli-1 pathway and increased the antileukemia activity of adriamycin against AML in vitro and in vivo. CONCLUSIONS: Inhibition of EZH2 by chidamide has antileukemia activity and increases the chemosensitivity to adriamycin through Smo/Gli-1 pathway in AML cells (Fig. 5). These findings support the rational combination of HDAC inhibitors and chemotherapy for the treatment of AML.

CD43 is an adverse prognostic factor in newly diagnosed multiple myeloma.

Currently, the expression pattern and prognostic value of CD43 expression in multiple myeloma (MM) remain unknown. 109 newly diagnosed MM patients were recruited and CD43 expression was determined by multiparameter flow cytometry, of which 77 (70.6%) were CD43 positive. Patients with positive CD43 expression were more likely to present with, hemoglobin < 85 g/L (p = 0.008), International Staging System (ISS) stage III (p = 0.044), 13q14 deletion (p = 0.034) and more monoclonal plasma cells (p = 0.003). Patients with CD43 positive had significantly poor treatment response (p = 0.021), progression-free survival (PFS) (p = 0.012), and overall survival (OS) (p = 0.023) than those without CD43. The poorer prognosis of CD43-positive patients was retained in multivariate analysis (p = 0.005 for PFS; p = 0.013 for OS). Our study indicated that CD43 was an independent adverse prognostic factor in multiple myeloma.

Nephrotic syndrome after allogeneic hematopoietic stem cell transplantation: etiology and pathogenesis.

In this study we investigated the etiology and pathogenesis of nephrotic syndrome (NS) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in 257 patients with hematopoietic malignancies who survived more than 2 months post allo-HSCT. Associations of NS with the conditioning regimen, graft versus host disease (GVHD), and other variables were analyzed. Pathologic features of the kidney, regulatory T cells (Tregs), interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α) were studied. NS was identified in 9 patients. The number of Tregs at day+30, 60, 90, and 180 was lower in NS patients than non-NS patients (P=0.001, 0.001, 0.007, 0.003). Serum levels of IFN-γ and TNF-α were higher in NS patients (P=0.032, 0.001, respectively). NS post allo-HSCT was associated with the occurrence of chronic GVHD (P=0.02). NS post-HSCT is an immune disorder that may involve immune complex deposition, Th1 cytokines, and Tregs.

[Immunol reconstitution after autologous purified CD34+ cells transplantation in patients with systemic lupus erythematosus].

OBJECTIVE: To investigate the variation of immune index in patients with systemic lupus erythematosus (SLE) treated with autologous purified CD34+ cells transplantation and to clarify the relationship with pathogenesis and prognosis. METHODS: Flow cytometry (FCM) and enzyme linked immunosorbent assay (ELISA) were used to test lymphocyte subsets, C3, C4, CH50, autoantibodies and immunoglobulin for 18 cases of SLE before and after transplantation. RESULTS: The results showed that the ratio of all the T cell subsets reduced obviously in early post graft and recovered gradually in 1 to 3 months after transplantation except CD45RO(+)CD4(+) cells. The levels of serum C3, C4, CH50 increased significantly after transplantation. No case relapsed within one year after transplantation, but 2 patients relapsed one year after transplantation. The levels of the indexes in the patients with relapse were significantly lower than those in the patients with persistent remission, including C(4) in the entire course, CH(50) in the 3rd and 12th month after transplantation and CD(45)RA(+)CD(8)+ cells in the 6th month after transplantation. However, the ratio of CD45RO(+)CD(4)+ cells in the first month after transplantation in the patients with relapse was higher than that in the patients with persistent remission. CONCLUSION: Autologous purified CD(34)+ cells transplantation is effective for treating SLE. Survey of immune indexes before and after transplantation is important to investigate the pathogenesis of SLE. Moreover, these immune indexes can be used to predict therapeutic efficacy of SLE.

[Recombinant adeno-associated virus 2-mediated green fluorescent protein expression in bone marrow mesenchymal stem cells derived from acute myelogenous leukemia patients].

OBJECTIVE: To explore the possibility of using autologous bone marrow mesenchymal stem cells (BMSC) as a vehicle to deliver recombinant adeno-associated virus 2-mediated enhanced green fluorescent protein (rAAV-2-eGFP) in vitro, therefore to find an alternative solution for gene therapy of hematological malignancy. METHODS: BMSCs isolated from the bone marrow of patients with acute myelogenous leukemia (AML) at the onset of disease were infected by rAAV-2-eGFP at different multiplicity of infection (MOI=10(2), 10(3), 10(4), 10(5), 10(6), and 10(7), respectively). Phase-contrast fluorescent microscope and flow cytometry were employed to evaluate the expression of enhanced green fluorescent protein (eGFP). RESULTS: Ten to fourteen days after the transfection, eGFP expression began to be detected and the transfection efficiency ranged between 0.3% to 2%, which failed to be increased with the increase of MOI. The transduced eGFP could maintain a long-term stable expression in vitro in the 61 days of observation, and from 12 to 33 days after transfection, eGFP percentage underwent a decrease from the initial 1.16% to 0.5%-0.6% and maintained this expression level till 61 days after transfection. CONCLUSION: rAAV can be used with BMSCs for in vitro gene therapy, but the poor transfection efficiency of these cells remains a significant obstacle for its further application.

[Establishment and Applications of Double-Fluorescent Protein Allo-Transplantation Mice Model].

OBJECTIVE: To establish allo-transplantation model by using mRFP⁺ to eGFP⁺ transgenic mice and to observe the distribution of donor cells and donor-recipient cellular interaction in the bone marrow after semi-solid decalcification (SSD). METHODS: After myeloablative irradiation, C57BL/6 female eGFP⁺ transgenic mice were infused with (5 × 106) bone marrow cells from FVB male donor mice through tail vein. The control group was infused with PBS. Then the general conditions, engraftment level, hematopoietic recovery, incidence of GVHD and survival of recipients were evaluated after transplantation. In the recovery process, SSD was used to treat the femora before observing the cells distribution, morphology and interaction by confocal microscopy directly or after making frozen section. RESULTS: WBC of recipient eGFP⁺ mice was recovered on (20 ± 3.07) d, (93.94 ± 1.59)% in peripheral cells were RFP⁺ cells (n = 10), GVHD happened in 4 of 10 mice within 1 month. During SSD, the hard components were replaced gradually and RFP⁺ cells could be seen mainly in the bone trabecula and surrounded by eGFP⁺ cells under confocal microscope, their interactions could be further observed clearly in bone marrow microenvironment in three-dimensional reconstruction. CONCLUSION: The double fluorescent allo-transplantation mouse model successfully established, by means of our novel protocol named SSD, the donor and recipient cell location and their interaction can be visually observed, which provides the basis for clinical studies on the distribution and homing of donor cells, and some related explorations after transplantation.

The relationship between clinical feature, complex immunophenotype, chromosome karyotype, and outcome of patients with acute myeloid leukemia in China.

Mixed phenotype acute leukemia (MPAL) is a complex entity expressing both lymphoid and myeloid immunophenotyping. In the present study, 47 MPAL, 60 lymphoid antigen-positive acute myeloid leukemia (Ly(+)AML), and 90 acute myeloid leukemia with common myeloid immunophenotype (Ly(-)AML) patients were investigated. We found that, in MPAL patients, there were high proportions of blast cells in bone marrow and incidence of hepatosplenomegaly, lymphadenopathy, and Philadelphia chromosome. The overall survival (OS) and relapse-free survival (RFS) in MPAL patients were significantly shorter than those in Ly(+)AML and Ly(-)AML. With regard to the patients with normal karyotype only, the OS and RFS of MPAL were significantly lower than those of the Ly(+)AML and Ly(-)AML; but there were no significant differences in OS and RFS among the patients with complex karyotype. The OS rates of 3 groups with complex karyotype were lower than those of patients with normal karyotype. In Cox multivariate analysis, complex karyotype was an independent pejorative factor for both OS and RFS. Therefore, MPAL is confirmed to be a poor-risk disease while Ly(+)AML does not impact prognosis. Complex karyotype is an unfavorable prognosis factor in AML patients with different immunophenotype. Mixed immunophenotype and complex karyotype increase the adverse risk when they coexist.

[Effect of autocrine vascular endothelial growth factor on the biological activity of acute myeloid leukemia cell line HL-60].

OBJECTIVE: To explore the effect of autocrine vascular endothelial growth factor (VEGF) on the abnormal proliferation of HL-60 cells. METHODS: HL-60 cells were transfected via lipofictamine with the VEGF(165) cDNA sense vector (HL-60/ VEGF(165)) and with the PcDNA3.1(-)-vector (HL-60/neo) as the control. Reverse transcription-polymerase chain reaction (RT-PCR) was used for detecting VEGF mRNA in the transfected cells. VEGF concentrations in the cell culture supernatant were determined by enzyme-linked immunosorbent assay (ELISA), and cell proliferation was determined by MTT assay and colony-forming assay in vitro. Flow cytometric Annexin-V-FITC/ PI dual-labeling technique was employed to observe the effect of VEGF(165) cDNA transfection on the apoptosis of HL-60 cells. RESULTS: The levels of VEGF mRNA expression by HL-60/VEGF(165) cells were higher than HL-60/neo, with the mean VEGF quantity in the supernatant of HL-60/VEGF(165) cell culture being 399.07+/-12.45 ng/L, which was 2-fold higher than that in the supernatant of HL-60/neo cells (184.45+/-10.53 ng/L) (P<0.01). The growth rate of HL-60/VEGF(165) cells was significantly accelerated as compared with that of the control cells, and the colony formation capacity of the former cells also increased significantly (P<0.05), with the average colony number of 157.00+/-17.00/500 cells vs 110.00+/-12.90/500 cells of HL-60/neo cells. Less apoptotic cells were identified among HL-60/VEGF(165) cells than in HL-60/neo cells in the same culture condition. CONCLUSION: Autocrine VEGF plays an important role in the proliferation and apoptosis of acute myeloid leukemia cells.

[Changes of peripheral blood CD45RA+ cells after hematopoietic stem cell transplantation: evaluation with four-color flow cytometry].

OBJECTIVE: To investigate the alteration of peripheral blood naive T cells in adult patients after hematopoietic stem cell transplantation (HSCT). METHODS: Peripheral blood samples were collected from 49 patients requiring stem cell transplantation before and 15, 30, 90, and 180 d after transplantation, respectively. Dynamic changes of CD4(+)CD45RA(+)/CD8(+)CD45RA(+) cell counting were measured using flow cytometry. RESULTS: Flow cytometry results of 90 samples showed that CD8(+)CD45RA(+) cells recovered to normal level 30 d after transplantation, whereas CD4(+)CD45RA(+) cells remained low and kept a slow pace of gradual increase over the 6 months following the transplantation. More rapid recovery of the transport and regeneration function of the thymus cells was achieved in patients receiving hematopoietic stem cell autotransplant than in those with allotransplant. CONCLUSION: Measurement of the changes of CD4(+)CD45RA(+)/CD8(+)CD45RA(+) cell ratio using flow cytometry may provide insights into the molecular picture of the thymus regeneration function in association with immune reconstruction process in patients after stem cell transplantation. The number of newly generated T cells transported from the thymus can be a putative marker of immune reconstruction after transplantation.

[Detection of platelet activation by flow cytometry in patients with pre-eclampsia].

OBJECTIVE: To explore the clinical significance of expression alterations of static and activated platelet glycoprotein CD41a, CD62p, and CD63 in patients with pre-eclampsia. METHODS: We used non-washing immunolabeling technique for fluorescence labeling of the static and activated platelet with CD41a, CD62p, and CD63 monoclonal antibodies of the blood samples from 16 patients with pre-eclampsia, 15 women with normal pregnancies and 20 healthy subjects. The expression of the monoclonal antibody was detected by flow cytometry. RESULTS: The average static and activated platelet glycoprotein CD41a, CD62p, and CD63 expression levels in patients with pre-eclampsia were apparently higher than those of the normal pregnant women (P<0.01), while the comparison between the latter and the control group did not reveal any significant differences (P>0.05). CONCLUSION: High levels of platelet glycoprotein CD62p and CD63 expressions are present in patients with preeclampsia, suggesting the presence of platelet activation in these patients.

Changes in peripheral blood Th1/Th2 cell balance in patients with condyloma acuminatum.

OBJECTIVE: To explore the association of peripheral blood T helper type 1 (Th1) and type 2 (Th2) imbalance with the occurrence of condyloma acuminatum (CA). METHODS: Interferon-gamma(IFN-gamma) and interleukin-4 (IL-4) secreted by CD4(+) T-cells were detected by flow cytometry in 40 patients with CA and 20 healthy volunteers, and significance of Th1/Th2 cell ratio in the etiology of the CA was analyzed. RESULTS: Peripheral blood Th1 cells that secreted IFN-gamma were significantly decreased in number in patients with CA (P <0.05), while Th2 cells producing IL-4 increased (P <0.05). The Th1/Th2 cell ratio was significantly reduced in CA patients as compared with the health control subjects (P <0.01). CONCLUSION: Increases of Th2 cells and decrease of Th1 cells in the peripheral blood of CA patients result in relative Th2 predominance and breach the Th1/Th2 balance, which may play an important role in the etiology and recurrence of CA.

[Hematopoietic reconstitution in early period after autologous and allogeneic peripheral blood stem cell transplantation].

OBJECTIVE: To investigate the ratio and amount of CD34+ cells and their subsets in mobilized peripheral blood (MPB) and leukapheresis products in patients receiving autologous peripheral blood stem cell transplantation (auto-PBSCT) and in allo-PBSCT donors, and clarify the role of CD34+ cells in post-transplantation hematopoietic reconstitution. METHOD: Sixteen patients receiving auto-PBSCT and 24 allo-PBSCT donors were studied for CD34+ and CD34+CD38- cell ratios in the 115 MPB and their leukapheresis product samples by way of flow cytometry, and the time of hematopoietic recovery was observed in the two groups. RESULTS: The CD34+ cell ratio in the MPB samples and leukapheresis products was significantly lower in the donors than in auto-PBSCT patients (P<0.05), but CD34+CD38- cell ratio showed no obvious difference between the two groups. The amount of mononuclear cells (MNCs) received by allo-PBSCT patients was much more than that received by auto-PBSCT patients (P<0.01). Similar average times for post-transplant neutrophils recovery to over 0.5x10(9)/L and platelets to over 2 x 10(10)/L (P>0.05) were observed between the groups, and in both of them, the recovery was related to the amount of MNCs, CD34+ and CD34+/CD38- cell infusion. CONCLUSION: Irrespective of auto-PBSCT or allo-PBSCT, the number of CD34+ and CD34+CD38-cells infused after the transplantation is the key factor to influence the course of hemopoietic reconstitution.

[Analysis of alkaline phosphatase staining results in 238 cases of malignant lymphoma].

OBJECTIVE: To examine the significance of alkaline phosphatase (ALP) staining in clinical characterization of malignant lymphoma cases. METHODS: Fresh peripheral blood smear obtained from 238 cases of malignant lymphoma, including 23 cases with bone marrow involvement (BMI) 189 cases without BMI(NBMI), and 26 cases of lymphoma cell leukemia (LCL), were examined by ALP staining, and the results were compared with those of 40 normal control subjects. RESULTS: With the gradual progression of lymphoma, the patients tended to have higher ALP scores, and the percentages of the subjects with a score higher than 250 in the control, NBMI, BMI and LCL were 0, 4.8%, 39.1%, 53.9% respectively, showing significant differences between the four groups. CONCLUSIONS: Increased ALP activity can be indirectly indicative of lymphoma progression, and ALP staining results may provide insight into the clinical staging and prognosis of malignant lymphoma.

[Immunophenotyping of 106 adult patients with acute leukemia by flow cytometry].

OBJECTIVE: To study the immunophenotyping of adult patients with acute leukemia and its association with the prognosis. METHODS: Immunophenotyping was performed in 106 adult patients with acute leukemia by three-color flow cytometry analysis using CD34/SSC gating. RESULTS: The antigens expressed in 71 patients with acute myeloid leukemia (AML) were mainly CD13, CD33, HLA-DR, CD34 and CD117. Lymphoid antigen expression was identified in 23.9% adult AML patients and CD56 antigen expression in 15.5% of the AML patients. In 29 patients with acute lymphoblastic leukemia (ALL), the expressed antigens were mainly HLA-DR, CD10, CD19, CD34 and CD7, and 34.5% of these patients were found to be positive for myeloid antigen expression. Complete remission (CR) rate in AML patients with lymphoid antigen expression after chemotherapy was lower than that in AML patients without lymphoid antigen expression (52.9% vs 77.8%, P<0.05), and no significant impact was noted of myeloid antigen expression in ALL on the CR of the patients (70.0% vs 94.7%, P>0.05). The CR rate in AML with CD56 antigen expression was lower than that in AML without CD56 expression (36.4% vs 78.3%, P<0.025), and the CR rate in CD34+ AML was lower than that in CD34- AML (56.0% vs 80.4%, P<0.05). CONCLUSIONS: Gating of CD45/SSC can eliminate the interference of normal cells to render more reliable immunophenotyping results. The expressions of CD56+, CD34+, lymphoid antigen in adult AML patients, who have lower CR rate, often signify poor prognosis.

Immunophenotypes and immune markers associated with acute promyelocytic leukemia prognosis.

CD2+, CD34+, and CD56+ immunophenotypes are associated with poor prognoses of acute promyelocytic leukemia (APL). The present study aimed to explore the role of APL immunophenotypes and immune markers as prognostic predictors on clinical outcomes. A total of 132 patients with de novo APL were retrospectively analyzed. Immunophenotypes were determined by flow cytometry. Clinical features, complete remission (CR), relapse, and five-year overall survival (OS) rate were assessed and subjected to multivariate analyses. The CD13+CD33+HLA-DR-CD34- immunophenotype was commonly observed in patients with APL. Positive rates for other APL immune markers including cMPO, CD117, CD64, and CD9 were 68.7%, 26%, 78.4%, and 96.6%, respectively. When compared with patients with CD2- APL, patients with CD2+ APL had a significantly higher incidence of early death (50% versus 15.7%; P = 0.016), lower CR rate (50% versus 91.1%; P = 0.042), and lower five-year OS rate (41.7% versus 74.2%; P = 0.018). White blood cell (WBC) count before treatment was found to be the only independent risk factor of early death, CR failure, and five-year mortality rate. Flow cytometric immunophenotype analysis can facilitate prompt APL diagnosis. Multivariate analysis has demonstrated that WBC count before treatment is the only known independent risk factor that predicts prognosis for APL in this study population.

[Anti-apoptotic effect of Astragalus Polysaccharide on myeloid cells].

This study was aimed to assess the effect of Astragalus Polysaccharide (ASPS) on in-vitro hematopoiesis. CFU-GM assays were used to determine the effect of ASPS and thrombopoietin (TPO) on granulocytic-monocyte progenitor cells. The CFU assays were also used to investigate the effect of ASPS on the proliferation of HL-60 cells.HL-60 cells were cultured with serum-free RPMI 1640 medium and treated with or without of different concentrations of ASPS. After 72 h incubation, the number of cells were counted.In addition, the caspase-3 and JC-1 expression was determined by flow cytometry with Annexin V/PI double staining. The results showed that ASPS (100, 200 µg/ml) and TPO (100 ng/ml) significantly promoted CFU-GM formation in vitro. Various concentrations of ASPS and TPO also promoted the colony formation of HL-60 cells, the largest effect of ASPS was observed at a concentration of 100 µg/ml. There were no synergistic effects between TPO and ASPS on cellular proliferation. The results also showed that ASPS significantly protected HL-60 cells from apoptosis in condition of serum-free medium culture, suppressed caspase 3 activation, and reduced the cell apoptosis. It is concluded that ASPS can significantly promote the formation of bone marrow CFU-GM and the proliferation of HL-60 cells, the optimal concentration of ASPS is at 100 µg/ml. In the absence of serum inducing apoptosis, ASPS also significantly reduced the apoptosis of HL-60 cells via suppressing the activation of caspase-3.

Synergistic effect of panobinostat and bortezomib on chemoresistant acute myelogenous leukemia cells via AKT and NF-κB pathways.

In this study, we investigated the synergistic effects of panobinostat and bortezomib on adriamycin-resistant HL60/ADR cells and refractory acute myelogenous leukemia (AML) primary cells. Combination of both agents had synergistic cytotoxicity on these cells, and increased the sensitivity of HL60/ADR cells to adriamycin. Panobinostat plus bortezomib was shown to modulate multiple apoptotic and drug metabolic related molecules, including activation of caspases, down-regulation of XIAP, Bcl-2 and MRP1. These effects were likely to be mediated via inhibition of AKT and NF-κB pathways. These findings provide evidence for clinic protocols using panobinostat and borezomib to overcome drug resistance in refractory AML patients.

Simultaneous analysis of telomere length and cell surface antigen in leukemia by multicolor Flow-FISH.

This study was purposed to explore the feasibility of simultaneous analysis of telomere length and cell surface antigen by multicolor Flow-FISH to assess minimal residual disease (MRD) in leukemia. The telomere length in 34 leukemia patients versus 20 normal controls was compared by using Flow-FISH, and the relationship between telomere length and therapeutic effect and prognosis was analyzed preliminarily. As for those patients with follow-up samples, the changes of telomere length combined with surface antigen in different courses of disease were observed by multicolor Flow-FISH. The results indicated that the telomere length of de novo patients was significantly shorter than that of controls except the patients in chronic myeloid leukemia-chronic phase (CML-CP). The shorter telomere, the lower complete remission (CR) rates were observed in acute leukemia cases and the shorter duration of CP before onset of blast phase (BP) occurred in CML cases. The acute leukemia patients showed longer telomere and fewer cells expressed the related antigen after CR. The telomere length of cases with continued CR remained at normal level during remission, and there was no increased expression of the specific antigen. However, the telomere of relapsed cases shortened again after relapse with elevated specific antigen expression. In the relapsed cases, the telomere of related antigen positive cells shortened ahead of telomere length change of the whole cells and morphologic change of bone marrow cells. It is concluded that analysis of telomere length by flow-FISH manifests the significance for monitoring disease conditions, estimating prognosis and guiding therapy in all kinds of leukemia. The simultaneous analysis of telomere length and cell surface antigen by multicolor flow-FISH may monitor abnormal clone or clonal evolution to predict recurrence more sensitively and specifically, and may provide a promising and widely applicable method for monitoring MRD in leukemia.

[Clinical characteristics and outcomes of 59 patients with acute lymphoblastic leukemia positive for BCR/ABL].

OBJECTIVE: To study the clinical characteristics and outcomes of BCR/ABL-positive acute lymphoblastic leukemia (BCR/ABL360888725-ALL) and screen the prognostic factors for BCR/ABL360888725-ALL. METHODS: From January 2001 to May 2008, 59 patients (median age of 32 years ranging from 3 to 69 years) with the diagnosis of BCR/ABL360888725-ALL by fluorescence in situ hybridization received induction chemotherapy with VDLP-/+Ara-C regimen. The patients who failed to respond to the chemotherapy received subsequent consolidation chemotherapy with imatinib (400-800 mg/day) (17 cases) or allogeneic hematopoietic stem cell transplantation (allo-HSCT) (16 cases). RESULTS: Of the 59 patients, 32 (58.3%) achieved complete remission (CR) after the first induction cycle. In patients with peripheral white blood cell (WBC) count <30=10(9)/L, 30-99.9(9)/L and > or =100(9)/L, the CR rates were 75.0% (18/24), 56.3% (9/15) and 26.3% (5/19) (P=0.006), and the overall survival probability of 2 years ( OSs of 2-yrs) was 24.7%, 22.5% and 21.1%, respectively (P=0.180). According to the FAB classification, 56 cases were divided into L1, L2 and biphenotypic acute leukemia (BAL) subgroups, and their CR rates were 66.7% (6/9), 63.2% (24/38) and 22.2% (2/9) (P=0.029), with OSs of 2-yrs of 22.2%, 27.0% and 22.0%, respectively (P=0.623). In terms of immunophenotype grouping by EGIL, the patients with ALL, myeloid antigen-positive ALL and BAL had CR rates of 61.1% (11/18), 60.6% (20/33) and 12.5% (1/8) (P=0.039), and the OSs of 2-yrs of 22.7%, 21.0% and 18.8%, respectively (P=0.643). In 55 patients with known karyotype, the CR rates were 71.4%(5/7), 70.8% (17/24) and 37.5% (9/24) in normal, sole t(9;22) abnormality, t(9;22) with additional abnormalities groups (P=0.046), with the OSs of 2-yrs of 42.9%, 34.0% and 7.3%, respectively (P=0.000). The patients complicated by septicemia had significantly lower OSs of 2-yrs than those without septicemia (0% vs 38.8%, P=0.005). The OSs of 2-yrs were significantly higher in patients with consolidation chemotherapy with imatinib than those without (48.0% vs 11.2%, P=0.001), and allo-HSCT was associated with significantly higher OSs of 2-yrs than exclusive chemotherapy (54.2% and 8.5%, P=0.000). CONCLUSION: BCR/ABL360888725-ALL with WBC> or =100 x 10(9)/L, presence of BAL diagnosed by FAB or FACM, t(9;22) with additional chromosome abnormalities all adversely affect the treatment results, and additional chromosome abnormalities and septicemia are associated with lower OSs of 2-yrs. Imatinib treatment and allo-HSCT can both improve the OSs of 2-yrs of the patients with BCR/ABL(+)-ALL.

[CD56 and CD11b antigen expressions in patients with acute monocytic leukemia and the clinical implications].

OBJECTIVE: To investigate the expressions of cell surface differentiation antigen CD56 and CD11b antigen in acute monocytic leukemic (AML-M(5)) cells and their clinical significance. METHODS: A total of 113 cases of de nove adult AML-M(5) were examined genetically and immunologically using G-banding technique, interphase fluorescence in situ hybridization (I-FISH) and flow cytometry immunophenotyping, and the results were analyzed in relation to their clinical data. RESULTS: Of the 113 cases, the expression rates of CD56 and CD11b was 28.32% and 73.45%, respectively. The CD56(+) patients had high CD11b expression, and the expression levels of CD11b and CD56 were positively correlated (P<0.05). The incidence of karyotypic abnormalities was 48.57% (55 cases) in these patients, including 25 (22.12%) with 11q23 aberrations. Twenty-five cases were positive for MLL gene abnormalities as found by I-FISH analysis. Compared with the patients positive for both CD56 and CD11b, those negative for both CD56 and CD11b showed increased peripheral blood white blood cell (WBC) count and also increased blast and progenitor cells in the bone marrow (P<0.05); the former patients often had karyotypic abnormalities, commonly involving 11q23 aberrations (P<0.05), whereas the latter patients presented more likely with extramedullary infiltration and refractory leukemia (P<0.01) with lowered complete remission rate and shortened median survival time (P<0.01). CD56-positive patients were more likely to have karyotypic abnormalities and refractory leukemia than CD11b-postive patients (P<0.05), but the peripheral blood WBC counts, bone marrow blast and progenitor cells, extramedullary infiltration, complete remission rate or median survival time showed no significant differences between them (P>0.05). CONCLUSION: AML-M(5) patients with CD56 positivity and high expression of CD11b often have aberrant karyotypes, commonly involving 11q23/MLL gene abnormality. These patients frequently develop extramedullary infiltration and refractory leukemia often with poor prognosis.