Value of S100A8 in evaluating the prognosis of children with acute lymphoblastic leukemia / 中国当代儿科杂志

OBJECTIVE@#To study the association between S100A8 expression and prognosis in children with acute lymphoblastic leukemia (ALL).@*METHODS@#The clinical data of 377 children with ALL who were treated with the CCLG-2008-ALL regimen were retrospectively reviewed. ELISA and PCR were used to measure serum protein levels and mRNA expression of S100A8. The Kaplan-Meier method was used for survival analysis and a Cox regression analysis was also performed.@*RESULTS@#The children were followed up for 56 months, and the overall survival rate of the 377 children was 89.1%. The prednisone good response group had significantly lower S100A8 protein and mRNA levels than the prednisone poor response group (P<0.01). In the children with standard or median risk, both S100A8 protein and mRNA levels were associated with event-free survival rate (P<0.05). There were significant differences in S100A8 protein and mRNA levels between the children with different risk stratifications (P<0.01). The children who experienced events had significantly higher S100A8 protein and mRNA levels than those who did not (P<0.01). The Kaplan-Meier survival analysis and the Cox regression model suggested that S100A8 overexpression was an independent risk factor for the prognosis of children with ALL.@*CONCLUSIONS@#High S100A8 expression may be associated with the poor prognosis of children with ALL and is promising as a new marker for individualized precise treatment of children with ALL.

Adenanthin Induces Differentiation of Acute Promyelocytic Leukemia Cells by Targeting Peroxiredoxin III / 中国实验血液学杂志

OBJECTIVE@#To investigate the differentiation of acute promyelocytic leukemia (APL) cells induced by adenosine targeting Prx III.@*METHODS@#HL-60 cells were divided into four groups: control group, all-trans retinoic acid (ATRA) group, adenanthin group and ATRA+adenanthin group. Cell morphologic changes were observed under optical microscope. The influence of adenanthin on the differentiation of HL-60 was observed by nitro blue tetrazolium chloride (NBT) test. Cell surface differentiation antigens CD11b expression was measured by flow cytometry. The protein expression of Prx III was detected by immunohistochemical assay.@*RESULTS@#Adenanthin could induce the differentiation of HL-60 cells; the NBT reduction positive rate in ATRA+adenanthin group was significantly higher than that in ATRA group and adenanthin group (P＜0.05). The percentage of CD11b positive cells in ATRA+adenanthin group (43.62％±1.38％) was higher than that in adenanthin group (28.15％±1.78％), ATRA group (36.72％±1.33％) and control group (7.99％±1.78％) (P＜0. 05). The content of Prx Ⅲ protein in adenanthin group was significantly higher than that in control group and ATRA group (P＜0.05).@*CONCLUSION@#Adenanthin and ATRA have a synergistic effect on the differentiation and maturation of HL-60 cells, and its mechanism may be related with regulation of Prx III expression.

The role of the PI3K/AKT signaling pathway in DADS-induced apoptosis of K562 cells / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the role of the PI3K/AKT signaling pathway in the diallyl disulfide (DADS)-induced apoptosis of K562 cells.</p><p><b>METHODS</b>K562 cells in the logarithmic growth phase were treated with 10, 20, 40, or 80 mg/L DADS for 48 hours, then fixed and stained with acridine orange/ethidium bromide (AO/EB), and examined for cellular morphological changes under an inverted microscope. Annexin V-FITC/PI staining was used for determining the apoptotic rates, and Western blot for measuring the expression of AKT, p-AKT, and Caspase-3. Two control groups, blank and solvent, were used as references.</p><p><b>RESULTS</b>K562 cells treated with DADS for 48 hours exhibited the characteristic morphological features of apoptosis including cell shrinkage, irregular cell shape, and membrane blebbing. AO/EB staining results demonstrated that the number of apoptotic cells with cell shrinkage, pyknotic or bead-like nuclei, chromatin condensation, and orange staining increased with the increasing DADS concentration, and 40 mg/L DADS had the most significant effect. The apoptotic rates of cells treated with 10, 20, 40, and 80 mg/L DADS were all significantly higher than those in the control groups (P<0.05). There were no significant differences in AKT protein expression between the K562 cells treated with different concentrations of DADS; the p-AKT protein expression decreased with the increasing DADS concentration, while the Caspases-3 protein expression increased with the increasing DADS concentration (P<0.05).</p><p><b>CONCLUSIONS</b>DADS induces the apoptosis of K562 cells, probably through inhibiting the protein expression in the PI3K/AKT signaling pathway.</p>

Mechanism of Fas/FasL signal transduction pathway in K562 cell apoptosis induced by diallyl disulfide / 中国实验血液学杂志

The aim of this study was to investigate the effect of diallyl disulfide (DADS) on the apoptosis of K562 cells and to explore the mechanism of K562 apoptosis induced by DADS. The K562 cells were treated with different concentrations of DADS for 24, 48 and 72 hours. The concentrations of DADS were as follows: 0 (control group), 10, 20, 40 and 80 mg/L. The morphologic changes of leukemia K562 cells treated with DADS were observed by Hoechst33 258 staining. The apoptosis of K562 cells treated with different concentrations of DADS for 24, 48 and 72 hours was analyzed by flow cytometry. The mRNA expression changes of Fas and FasL were detected by reverse transcription-polymerase chain reaction (RT-PCR) after K562 cells were treated with different concentrations of DADS for 48 hours. The results indicated that the characteristics of apoptosis in K562 cells induced by DADS were as follows: reduction of nucleus, chromatin condensation and nuclear membrane rupture. The flow cytometry with PI straining showed that after 24 hours of DADS treatment the apoptosis rate of K562 cells increased from 11.60 ± 0.83% at the concentration of 10 mg/L to 37.94 ± 0.87% at the concentration of 40 mg/L. The apoptosis rate of K562 cells increased from 37.94 ± 0.87% (24 hours) to 47.02 ± 0.66% (72 hours) after treatment with DADS of 10 mg/L increasing to 40 mg/L DADS. The Fas mRNA expression levels of the related apoptotic genes increased after K562 cells were treated with different concentrations of DADS for 48 hours, while FasL mRNA expression decreased significantly after DADS treatment for 48 hours, compared with those in the control group (p < 0.05). It is concluded that DADS can induce the apoptosis of human leukemia K562 cells in a time-and concentration-dependent manners. The activation of Fas/FasL pathway may play an important role in the K562 cell apoptosis induced by DADS, which is associated with increasing Fas gene expression and decreasing FasL gene expression.

Effects of diallyl disulfide on apoptosis of human leukemia K562 cells and expression of Fas, FasL and caspase-8 / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effects of diallyl disulfide (DADS) on apoptosis of human leukemia K562 cells and possible mechanisms.</p><p><b>METHODS</b>The morphologic changes of leukemia K562 cells after DADS treatment were observed by Hoechst 33258 staining. Cell apoptosis rates after different concentrations and different durations of DADS treatment were determined by flow cytometry. Fas, FasL and caspase-8 mRNA expression was estimated by reverse transcription-polymerase chain reaction (RT-PCR) 48 hrs after DADS treatment.</p><p><b>RESULTS</b>The characteristics of apoptosis in K562 cells induced by DADS were observed. After 24 hrs of DADS treatment, the apoptosis rate of K562 cells increased from (11.60 ± 0.83)% at the concentration of 10 mg/L to (37.94 ± 0.87)% at the concentration of 40 mg/L. The apoptosis rate of K562 cells increased after 40 mg/L DADS with the increasing time from (37.94 ± 0.87)% (24 hrs) to (47.02 ± 0.66)% (72 hrs). Expression of Fas and caspase-8 mRNA increased, while FasL mRNA expression decreased significantly 48 hrs after DADS treatment compared with the control group (P<0.05).</p><p><b>CONCLUSIONS</b>DADS can induce apoptosis of human leukemia K562 cells in a time- and concentration-dependent manner, possibly through increasing Fas and caspase-8 expression and decreasing FasL expression.</p>

Stem cell factor secretion by bone mesenchymal stem cells stimulated with astragaloside IV / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effect of astragaloside IV on the expression of cytokines in bone mesenchymal stem cells (MSCs) in rats.</p><p><b>METHODS</b>MSCs were isolated from Wistar rats by the method of adhesive cultiration and clone, and then their biological activities were assessed using indirect immunofluorescence. Proliferation of MSCs stimulated with astragaloside IV was ascertained by the MTT method. Expression of cytokines was ascertained using RT-PCR in MSCs with astragaloside IV stimulation or not.</p><p><b>RESULTS</b>MSCs were effectively isolated and purified in vitro, and had expression of many cytokines except IL-3, such as stem cell factor (SCF), thrombopoietin (TPO), granulocyte macrophage colony stimulating factor (GM-CSF) and transforming growth factor (TGF-beta1). Astragaloside IV stimulation promoted MSCs proliferation, and 200 mg/mL astragaloside IV treatment produced a peak effect 72 hrs after culture. The SCF expression in MSCs stimulated with astragaloside IV increased significantly compared with that in MSCs without astragaloside IV stimulation.</p><p><b>CONCLUSIONS</b>Astragaloside IV may promote MSCs proliferation and increase SCF secretion in vitro.</p>

Effects of CXCR4 silence induced by RNA interference on cell cycle distribution and apoptosis of Jurkat cells / 中国实验血液学杂志

This study was aimed to investigate the effect of down-regulating the CXCR4 expression on cell cycle and cell apoptosis of human T-ALL Jurkat cells. The CXCR4 specific siRNA plasmid vector was constructed and then transfected into the cultured Jurkat cell line by DMRIE-C. The expression of CXCR4 mRNA was detected by RT-PCR, the cell distribution in cell cycle and cell apoptosis were determined by flow cytometry. The experiments were divided into 3 groups: group A (blank control), group B (non-silencing dsRNA as negative control) and group C (CXCR4 siRNA). The results showed that the expression level of CXCR4 mRNA in Jurkat cells transfected with CXCR4 siRNA (group C) decreased and cell proportion in G(0)/G(1) phase increased as compared with group A (56.9% +/- 1.4% vs 68.3% +/- 2.4% and 35.8% +/- 1.9% vs 18.1% +/- 1.2% respectively) (p < 0.01), cell proportion in G(2)/M and S phase decreased as compared with group A (19.8% +/- 1.7%, 44.4% +/- 2.1% vs 27.2% +/- 1.5%, 54.7% +/- 2.8% respectively) (p < 0.01). The apoptosis rate of Jurkat cells in group C increased as compared with group A (20.9% +/- 2.0% vs 3.13% +/- 0.9% respectively) (p < 0.01), and the comparison between group A and B showed no statistical difference. It is concluded that the CXCR4 specific siRNA can effectively down-regulate the CXCR4 mRNA expression, which induces the cell apoptosis and cell cycle arrest, thereby inhibits the Jurkat cell proliferation.