Successful management of acute myeloid leukemia transformed from chronic myelomonocytic leukemia in the elderly by a combination regimen of decitabine and cytarabine, aclarubicin and granulocyte colony-stimulating factor: A case report.

Despite advances in the treatment of acute myeloid leukemia (AML) in recent years, the outcome of elderly AML patients with antecedent hematological disorders remains unsatisfactory. The present study describes a case of complete remission in an elderly patient with AML transformed from chronic myelomonocytic leukemia (CMML) and the treatment of the case with decitabine in combination with cytarabine, aclarubicin and granulocyte colony-stimulating factor (CAG). A 70-year-old male was admitted with fever, pruritus and weakness that had been apparent for two weeks, and a two-year history of monocytosis (22.5-27.0%). Further examinations revealed a hemoglobin level of 106 g/l, a white blood cell count of 39.52×109/l, a platelet count of 81×109/l, Y chromosome loss and uniparental disomy on chromosomes 4q, 2q and 19p. The patient was diagnosed with AML transformed from CMML, with cytogenetic anomalies. A combination regimen of decitabine and CAG was administered. Subsequent to one cycle, the patient achieved complete remission. The patient was then followed up with three courses of the same regimen and achieved clinical remission, with no evidence of AML relapse. The present study suggests that a combination of low-dose decitabine and CAG may offer a novel and potentially effective treatment regimen for elderly AML patients.

Effect of CIK on multidrug-resistance reversal and increasing the sensitivity of ADR in K562/ADR cells.

Leukemia is a leading cause of cancer-related mortality in children worldwide, and multidrug-resistance (MDR) is a main reason for tumor chemotherapy failure. The present study investigated the effects of ADR following incubation with cytokine-induced killer (CIK) cells on reversing MDR in K562/ADR cells. Mononuclear cells were isolated from the peripheral blood of healthy individuals and cultured in vitro in the presence of a combination of cytokines to generate CIK for K562/ADR cell treatment. A decreased level of P-glycoprotein expression and glutathione (GSH), an increased intracellular Rh-123 content, decreased mRNA and protein expression levels of MDR gene 1, MDR-associated protein 1, GSH S-transferase-π, B-cell lymphoma 2 and Survivin, and the decreased phosphorylation of AKT and the transcriptional activity of nuclear factor-κB and activator protein 1 were detected following ADR treatment in CIK co-cultured K562/ADR cells. Additionally, the level of ADR sensitivity and the apoptosis rate were increased in the CIK co-cultured K562/ADR cells. These results indicate that pre-treatment with CIK could reverse the MDR of K562/ADR cells, and that patients would be most likely to benefit from the combination of chemotherapy and CIK therapy.

[In vitro effect of iron overload on bone marrow cell function by inducing the reactive oxygen species].

OBJECTIVE: To investigate the in vitro effect of iron overload on the generation of reactive oxygen species (ROS) and of bone marrow (BM) cell function. METHODS: BM mononuclear cells (BMMNCs) were cultured with ferric citrate (FAC) at different concentrations and for different time to create iron overload and confirmed by the detection of cellular labile iron pool (LIP). The changes of ROS, apoptosis, hematopoietic colony formation (CFU-E, BFU-E, CFU-GM and CFU-mix) and the percentage of the CD34 + cells percentage were analyzed. The differences of these index were tested after the iron overload treated with deferasirox (DFO) or antioxidants (N-acetyl-L-cysteine, NAC). RESULTS: 1) When BMMNCs were cultured with FAC, the LIP was found to increase in a time and concentration dependent manner. The intracellular LIP reached maximum at 400 micromol/L of FAC for 24 hours. 2) The ROS of total cells, leukocytes and erythrocytes increased to 1.77, 1.75 and 2.12 fold respectively compared with that of normal control when cells were cultured at 400 micromol/L of FAC for 24 hours . DFO and NAC could reduce the ROS efficiently (P<0.05). 3) The apoptotic rates of the FAC treated cells [(24.80 +/- 2.99)%] increased significantly compared with that of normal control [(8.90 +/- 0.96)%]. The capacity of hematopoietic colony formation in FAC treated cells decreased markedly compared with that of normal control (P<0.05). The percentage of CD34+ cells of FAC treated cells [(0.39 +/- 0.07)%] also decreased significantly compared with that of normal control [(0.91 +/- 0.12)%]. And these changes could be recovered by addition of NAC or DFO. CONCLUSION: Iron overload can affect the hematopoiesis by inducing the generation of ROS and this damage could be corrected by removing the excess iron and ROS of the BM cells. These findings might improve the treatment of dyshematopoiesis in patients with iron overload.

[Effects of oxidative stress on hematopoiesis of hematopoietic stem and progenitor cells with iron overload].

OBJECTIVE: To establish a model of hematopoietic stem and progenitor cells with iron overload derived from umbilical cord blood (UCB) cells and explore the effects of reactive oxygen species (ROS) on the hematopoiesis of hematopoietic stem and progenitor cells with iron overload. METHODS: The model was established by adding different concentrations (50, 100, 200, 400 µmol/L)of ferric citrate (FAC) into mononuclear cells from UCB and culturing for different times (6, 12, 24 h). The UCB cells were divided into 4 groups: control group, group FAC, group FAC+N-acetyl-L-cysteine (NAC) and group FAC+ L-Glutathione (GSH). Then the changes of ROS, labile iron pool (LIP), apoptosis, the capacity of hematopoietic colony forming (CFU-E, BFU-E, CFU-GM, CFU-mix) and the percentage and the numbers of CD34(+), CD33(+), GlyA(+) cells were detected. And the changes of these indices were tested after the treatment of iron overload UCB with antioxidants (NAC and GSH). RESULTS: UCB cells were cultured with the addition of FAC at different concentrations for different times. The level of total ROS increased in time and concentration-dependent manners. The intracellular level of ROS peaked when cultured at 200 µmol/L of FAC for 24 hours. Cells were treated with antioxidants NAC or GSH after cultured with 200 µmol/L FAC for 24 hours. Then the ROS levels of total cells, myeloid cells and erythroid cells decreased markedly versus normal controls. The LIP of total cells, myeloid cells and erythroid cells increased markedly when cells were cultured at 200 µmol/L of FAC for 24 hours versus normal controls (P < 0.05). NAC and GSH had no effect on the level of LIP. The apoptotic rates of FAC-treated cells [(20.90 ± 3.45)%] increased significantly versus normal controls [(9.20 ± 1.29)%] (P < 0.05). The capacity of hematopoietic colony forming in FAC treated cells decreased markedly versus normal controls. The percentage and numbers of CD34(+), CD33(+), GlyA(+) cells of FAC-treated cells also decreased significantly versus normal controls (P < 0.05). And these changes could be recovered by the addition of NAC or GSH. CONCLUSION: Oxidative stress plays an important role in the injuries of hematopoiesis of hematopoietic stem and progenitor cells with iron overload by inducing the generation of ROS. These findings may help us find a specific target and improve the therapeutic efficacy of ineffective hematopoiesis in patients with iron overload.

[Effects of interleukin 21 on anti-leukemia activity of cytotoxic T lymphocytes induced by dendritic cells].

This study was aimed to explore the effects of interleukin 21 (IL-21) on the anti-leukemia activity of cytotoxic T lymphocytes (CTL) induced by dendritic cells (DCs) in vitro. The peripheral mononuclear cells from leukemia patients in complete remission were cultured with the specific cytokines to induce the production of DCs. The DCs loaded with RNA from autologous leukemic cells as antigen, and co-cultured with autologous T lymphocytes to get leukemia specific CTL. The cytotoxic activity of CTL against autologous leukemic cells was measured by LDH release method. The concentration of IFN-gamma and TNF-alpha in the culture supernatant was measured by enzyme immunoassay. The effects of IL-21 on the mature DCs were also studied by the measurement of the phenotype of DC and the allogenic mixed lymphocytic reactions induced by DCs. Experiments were divided into 2 groups: test group in which IL-21 (200 ng/ml) was added in coculture of DC/CTL and control group in which no IL-21 (200 ng/ml) was added. The results showed that when cultured with IL-21, the quantity of CTL increased from (56.73 +/- 10.21)% (control group) to (73.43 +/- 18.01)% (p < 0.01); The concentration of IFN-gamma and TNF-alpha in the culture supernatant increased from (154.91 +/- 67.20) ng/L (control group) to (310.62 +/- 141.15) ng/L (p < 0.01) and from (8.77 +/- 5.09) microg/L (control group) to (15.25 +/- 6.56) microg/L (p < 0.01) respectively. At the effector: target ratio of 20:1, the cytotoxic activity against autologous leukemic cells by CTL increased from (50.22 +/- 5.07)% (control group) to (75.38 +/- 9.47)% (p < 0.01). IL-21 had neither effect on the phenotype (CD1a, CD83, CD86, CD80 and HLA-DR) of mature DCs nor the allogeneic mixed lymphocytic reactions induced by DCs. It is concluded that IL-21 can strengthen the proliferation of CTL, and improve the production of IFN-gamma and TNF-alpha, thus enhance the anti-leukemia activity of CTL. Nevertheless, there is no effect of IL-21 on the function of mature DCs. These data indicate that IL-21 has a potential clinical value in the enhancement of anti-leukemia immunotherapy.

[Wilms' tumor-1 gene expression in myelodysplastic syndrome and its changes in the process of myelodysplastic syndrome transforming into acute leukemia].

OBJECTIVE: To observe expression of Wilms' tumor-1 (WT1) gene in the different subtypes of myelodysplastic syndrome (MDS), and to explore the regularity of expression of WT1 gene in the process of MDS transforming into acute leukemia (AL). METHODS: The method of reverse transcriptase-polymerase chain reaction (RT-PCR) was used, the levels of WT1 gene's presentation in different types of montagers of MDS were analyzed, and the relationship between the level and the clinical characteristic was analyzed. At the same time, the expression of WT1 gene in AL patients, post-MDS-AL patients and normal controls were examined. RESULTS: The positive rate of WT1 gene expression in 49 patients with MDS was 22.4 percent (11/49), refractory anemia (RA) was 0(0/13), RA with excess of blast (RAEB) was 25.0 percent (6/24); RAEB in transformation (RAEB-t) was 41.7 percent (5/12). The positive rates of WT1 expression were gradually increased in three types of MDS (P<0.05 and P<0.01). The positive rates of WT1 expression were higher in AL and post-MDS-AL patients (48.5 percent, 32/66 and 50.0 percent, 4/8) than that in MDS patients (P<0.01). There was no expression of WT1 gene in normal control. CONCLUSION: There is a relatively high expression rate of WT1 gene in RAEB, RAEB-t of MDS, but relatively low expression rate in RA. The method of RT-PCR, is high sensitiveness and specificity, can trustful be used in the progression of monitoring MDS' progression and its transformation into AL.