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Objective: To investigate the clinical efficacy of Fu Fan Huang Dai Pian(RIF) and arsenic trioxide (ATO) regimens for treatment of children with acute promyelocytic leukemia (APL) and to explore the risk factors affecting the prognosis of patients., Methods: The clinical data of 45 newly diagnosed APL children admitted in our hospital from January 2004 to May 2017 were analyzed retrospectively. Among 45 APL children, 25 children were treated by chemotherapetic regimen including RIF (RIF group), another 20 children were treated by chemotherapeutic regimen including ATO (ATO group). The follow-up was performed in all APL children. The prognosis and incidence of side reactions from drugs in 2 groups were compared, and the high risk factors affecting the prognosis of patients were analyzed., Results: The median follow-up time was 49.8% months. In RIF group, no early death occured in 25 APL children; 5 cases did not achieve complete remission (CR) after induction therapy, CR rate was 88%. Out of 25 cases 2 caes relapsed, 3 cases died, 20 cases maintained contined CR (CCR), 2 cases failed to be followed-up. In ATO group, 2 cases suffered from early death, 5 cases did not achieve CR after induction therapy, CR rate was 90%, 2 caese relapsed and died, 15 cases maintained CCR, the follow-up failed in 1 caes. The 5 year- OS and EFS rate in all the patients were predicted as (82.2±6.2)% and (76.4±6.6)% respectively. The OS and EFS rate in RIF group were (86.1±7.4)% and (78.4±8.6)% respectively, which were significantly different from OS and EFS rate (76.4%±10.6%) and (74.0%±10.1%) respectively in ATO group (all P>0.05). As for the side reaction from drug, except for the cardiac damage (P<0.05), incidence of other side reactions was not significantly different between 2 groups (P>0.05). In addition, the 5 year-OS and EFS rates in APL children with CNSL were significantly lower than those in APL children without CNSL (all P<0.05), the 5 year OS and EFS rate in APL children did not reache M1 and with high risk were significantly lower than those in APL children reached M1 after induction therapy and with low and standerd risk (P<0.05 and P<0.05); the 5 year-OS and EFS rates did not correlate with age and sex., Conclusion: The Fu Fang Huang Dai Pian shows the therapeutic efficacy on APL children same as ATO, moreover, no obvious enhancement in incidence of side reactions is observed, therefore, the Fu Fang Huang Dai Pian is effective and safe for treatment of APL children. The CNSL, poor respond to treatment, high risk in clinical stratification are high risk factors affecting prognosis of patients.

Objective: To investigate the effects of metformin on proliferation and apoptosis in multiple myeloma cell line RPMI8226 and U266, and to clarify the molecular mechanism of proliferation inhibition and apoptosis induced by metformin., Methods: RPMI8226, U266 cells were treated with 0, 5, 10, 20, 40, 80 mmol/L of metformin for 24, 48 and 72 hours, then the inhibition rate was detected by CCK-8; RPMI8226 cells were treated with 0, 10, 20, 40 mmol/L of metformin for 48 hours, the apoptosis rates were detected by flow cytometry with Annexin-V-FITC/PI double staining; RPMI8226 cells were treated with 0, 5, 10, 20 mmol/L of metformin for 48 hours, the expressions of Caspase-3, PARP, STAT3, p-STAT3, BCL-2, Cyclin D1 and P21 were detected by Western blot., Results: The inhibition rate increased in RPMI8226 and U266 cells treated with metformin in the dose- (r=0.982, r=0.967, P<0.05) and time-dependent (r=0.956, r=0.962, P<0.05) manner; the apoptosis rate increased(r=0.976, P<0.05) in RPMI8226 cells treated with metformin; it also was found that procaspase-3 was degraded and PARP was cleaved when treated with metformin. Proliferation inhibition and apoptosis of RPMI8226 cells were related with inhibition of STAT3 phosphorylation, down-regulation of BCL-2 and Cyclin D1, and up-regulation of P21., Conclusion: Metformin can inhibit the proliferation and induce apoptosis of RPMI8226 and U266 cell lines, which may be related to down-regulation of STAT3 signal transduction pathway.

Objective: To explore the mRNA expression of Aurora-A,B,C(AUR-A,B,C) in acute leukemia(AL) and their correlations with the clinical indications., Methods: The mRNA expression levels of AUR-A,B,C in 73 cases of newly diagnosed AL (untreated group), 20 cases of AL with remission (remission group) and 14 healthy volunteers as control (healthy group) were detected by QRT-PCR, and the difference of expression levels in difference groups, their correlations with clinical indicators and the correlation between the AUR-A,B,C mRNA expression levels themselves were analyzed., Results: The mRNA expression levels of AUR-A,B,C in untreated group were all higher than those in healthy group and remission group(P<0.01), but there was not significant difference between healthy group and remission group(P>0.05); the mRNA expressions of AUR-A,B,C in acute lymphoblastic leukemia(ALL) group were all significantly higher than that in AML group(P<0.01). The mRNA expression of AUR-A,B,C in high risk group was higher than that in low risk group(P<0.05), but there was no difference in mRNA expression of AUR-A,B,C between high risk group and middle risk group as well as between middle risk group and low risk group(P>0.05). The mRNA expression of AUR-A, B, C in CD34, CD71 and CD56 negative group was not statistically different from that in CD34,CD71 and CD56 positive group(P>0.05). In 73 cases of newly diagnosed AL, the mRNA expression levels of AUR-A, B significantly were positively correlated with lactate dehydrogenase(LDH) level and risk stratification (r=0.279, P=0.017; r=0.314, P=0.007 and r=0.277, P=0.018; r=0.349, P=0.002), while the mRNA expression levels of AUR-A, B were not significantly correlated with age, WBC count, blast ratio in bone marrow at initial diagnosis and remission or no-remission after 1 cours of chemotherapy; the mRNA expression level of AUR-C was significantly positively correlated with WBC count (r=0.263, P=0.025), and LDH level (r=0.348, P=0.003) at initial diagnosis and risk stratificantion(r=0.376, P=0.001), and negatively correlated with age (r=-0.241, P=0.040), and was not significantly correlated with blast ratio in bone marrow at initial diagnosis and remission or noremission after 1 course of chemotherapy. There were significant positive correlations in the mRNA expression between AUR-A and B (r=0.444, P=0.000), AUR-B and C (r=0.763, P=0.000) as well as AUR-A and C (r=0.616, P=0.000)., Conclusion: Aur-A, B, C mRNA were highly expressed in patients with newly diagnosed AL, moreover the mRNA expression levels of Aur-A,B,C were positively correlated with each other, the high expression of Aur-A, B, C are associated with leukemia types, risk stratification, WBC count and LDH level at initial diagnosis, so they all maybe used as the prognostic markers and potential therapeutic targets.

Objective: To investigate the inhibitory effect of indomethacin combined with imatinib on proliferation of KCL22 and K562/G01 cells, and to elucidate the molecular mechanism of antiproliferative effect by Wnt/β-Catenin signaling way., Methods: Indomethacin was used in KCL22 and K562/G01 cells. The cell growth was detected by MTT assay to explore the optimal concentration and time. The effect of drugs on proliferation capacity was assessed by MTT assay and colony-forming assay. Flow cytometry was used to identify the cell cycle and apoptosis changes. The protein expression of pβ-catenin (S33/37/T41), pGSK-3β (Ser9) and C-MYC were analyzed by Western blot., Results: The optimal concentration and time of indomethacin on KCL22 and K562/G01 were 80 µmol/L for 48 h. The inhibitory effect of 80 µmol/L indomethacin combined 2 µmol/L imatinib on cell proliferation was significantly better than a single drug treatment. Flow cytometry results showed that cell cycle was arrested in the G0/G1 phase in both combined treatment groups. The number of apoptosis cells in combined treatment groups was significantly higher than that in single drug treatment groups. Compared with the control group or single drug treatment groups, the protein level of pβ-catenin, β-catenin, pGSK-3β (Ser9) and C-MYC decreased significantly., Conclusion: Indomethacin significantly enhances inhibitory effect of imatinib on proliferation of KCL22 and K562/G01 cells and regulate cell proliferation through Wnt/β-Catenin signaling way.

Unlabelled: Objetive: To investigate the effects of PKF118-310 on cell cycle and proliferation of K562 cell lines and its mechanism., Methods: After treatment of PKF118-310 with different concentration, the proliferation inhibition on K562 cell lines was detected by MTT, the existance of β-catenin and TCF-4 in the cells was observed by immunohistochemistry. The change of the cell cycle was detected by flow cytometry. The expressions of caspase-3, β-catenin, TCF and BCL-9 were detected by Western blot., Results: PKF118-310 can inhibit the proliferation of K562 cell line by S phase blocking. The β-catenin and TCF in the cells were observed by immunohistochemistry. After treating this cell line with PKF118-310 of different concentrations for 72 h, the expression level of caspase-3 increased, the expression levels of β-catenin, TCF and BCL-9 significantly decreased., Conclusion: PKF118-310 induces cycle arest of K562 cells at the S phase and inhibits the proliferation of these cells through decreasing β-catenin/TCF/BCL-9 thrascriptional activity.

Objective: To investigate the effect of SH2-Caspase 8 fusion protein expressed by recombinant adenovirus AdE-SH2-Caspase8-HA-GFP (SC) on the apoptosis of K562/G01 cell line, which is a BCR/ABL positive chronic myeloid leukemia cell line and resistant to imatinib., Methods: The K562/G01 cell line was infected with AdE-SH2-Caspase 8-HA-GFP adenovirus (SC), then the cells were divided into 3 groups: AdE-SH2m-Caspase 8-HA-GFP (SmC) group, AdE-GFP (CMV) group and PBS group as control. The infection efficiency was observed under fluorescent microscopy and by flow cytometry. The expression of fusion protein SH2-Caspase 8-HA was measured by Western blot. The morphology of the cells detected by Wright's staining. The apoptosis of the cells were detected by flow cytometry and DNA ladder. The expression of Caspase 3 and PARP were detected by Western blot., Result: The infection efficiency of SC on K562/G01 cells was high which was confirmed by fluorescent microscopy and FCM. SH2-Caspase 8-HA fusion protein were expressed correctly in K562/G01 cells. After treatment with SC the apoptosis of K562/G01 cells could be observed by microscopy. The result of FCM showed that early apoptosis of K562/G01 cells increased significantly as compared with control groups (P < 0.05). DNA ladder showed that the classic DNA ladders appeared in K562/G01 cells after treatment with SC. The wester blot detection showed that the expression level of apoptosis-related protein Caspase 3 and PARP increased., Conclusion: The recombinant adenovirus SC expressing SH2-Caspase 8 fusion protein can induces the apoptosis of K562/G01 cells.

The aim of this study was to investigate the apoptosis-inducing effect of cinnamic aldehyde (CA) on chronic myeloid leukemic (CML) cells and its mechanism. K562 cells and primary bone marrow mononuclear cells (MNC) from patients with CML were treated by various concentrations of CA. Flow cytometry was employed to measure the apoptosis of K562 cells and primary CML bone marrow MNC. Western blot was used to determine the expression of C-MYC and the phosphorylation of CrkL in K562 cells, and real-time polymerase chain reaction (real-time PCR) was used to quantify the expression of BCR-ABL mRNA in K562 cells. The results indicated that CA induced the apoptosis of K562 cells in a time- and dose-dependent manner. CA induced apoptosis of CML MNC dose-dependently. CA inhibited the expression of BCR-ABL mRNA and C-MYC, reduced CrkL phosphorylation levels in K562 cells. It is concluded that CA induces apoptosis of CML cells in vitro. Down-regulation of the expression and function of BCR-ABL may be one of its most important anti-leukemia mechanisms.

Different cytokines are needed in the course of culturing cells to do adoptive immunotherapy. This study was aimed to investigate the differentiation directions of lymphocytes and related gene expression characteristics after combined stimulation of lymphocytes by different cytokines or EBV antigen peptide combined with cytokines. The experiment was divided into 4 groups. The levels of total T lymphocytes (CD3(+)), T helper lymphocytes (CD3(+)CD4(+)), cytotoxic T-lymphocyte (CD3(+)CD8(+)), memory T cells (CD3(+)CD8(+)CD45RO(+)), naive T cells (CD3(+)CD8(+)CD45RA(+)), Th2 cells (CD3(+)CD30(+)), B cells (CD19(+)), NK cells (CD56(+)), naive T regulatory cells (CD4(+)CD25(+)), precise T regulatory cells (CD4(+)CD25(+)FOXP3(+)) were detected by flow cytometry. The expression levels of house-keeping gene (mad1, pten), T helper cells transcriptional regulatory gene t-bet (Th1), gata3 (Th2), cytokine IFN-γ(Th1), IL-4(Th2) were detected by using RT-PCR. The results showed that CTL in EBV polypeptide group were dominant cells with certain clinical effects. Comparison of result of EBV polypeptide group with other 3 different cytokine stimulating groups demonstrated that EBV antigen peptide had much more effects on stimulating CTL generation. The expression of IFN-γ gene was significantly increased; the T helper differentiation-related gene t-bet, gata3 also increased evidently, while expression change of house-keeping gene mad1 and pten were not evident. Addition of different cytokines and antigen peptides in culture may be much more effective on stimulating CTL generation. It is concluded that specific CTL can be obtained by using the lymphocytes co-cultured with EBV and cytokines, and the different cytokines play different roles in cell differentiation.

This study was purposed to analyze the changes of T-cell clonality after induction of peripheral T lymphocytes by autogenous DC and cytokines in the preparation of adoptive immunotherapy for leukemias. The bone marrow and peripheral blood from 21 leukemia patients at remission stage after treatment and subjected to adoptive immunotherapy were collected. Their DCs and T-cells were stimulated with cytokines and then were mixed to activate T-cells. T-cell receptor beta variable region (TCRBV) families were amplified by RT-PCR, and genescan method and sequencing of the PCR products were used to observe the clonality changes of T-cells before and after the induction and cultivation of T-cells. The flow cytometry was used to identify CD3(+), CD4(+), CD8(+), CD3(+)CD56(+) and CD4(+)CD25str(+)FOXP3(+) cells to disclose the ratio change of cytotoxic T lymphocytes (CTL), helper T-cells, regulatory T-cells and NK T-cells before and after induction and cultivation of T-cells. The results showed that in the 21 patients, most of the 24 TCRBV families presented as oligoclonal distribution on genescan, several families were not expressed, and only a few families remained polyclonal. TCRBV24 was found to be oligoclonal in all of the 21 patients. DNA sequence analysis of TCRBV24 revealed a common motif of VAG in CDR3 in 3 cases and a common motif of GGG in CDR3 in 2 cases. In patient 5, both TCRBV 24 and TCRBV8 contained the same motif of GGG in CDR3. The identical motif in these patients may suggest that these T-cells recognize the same antigen. The peripheral lymphocytes demonstrated recovery of clonal profile on genescan from oligoclonal profile and absence of several families before the induction and cultivation to typical polyclonal profile in all TCRBV families after the induction by DC and cytokines for 13 days. After the induction and cultivation, the number of lymphocytes increased to 3.38 +/- 1.20 times. CD3(+), CD4(+), CD8(+), CD3(+)CD56(+) and CD4(+)CD25str(+)FOX P3(+) cells were 71.1 +/- 11.8%, 26.7 +/- 11.4%, 35.7 +/- 12.9%, 3.1 +/- 1.6% and 0.12 +/- 0.1% respectively before the induction and cultivation, and changed to 95.4 +/- 3.2% (p < 0.01), 27.0 +/- 13.1% (p > 0.01), 55.5 +/- 13.8% (p < 0.01), 9.8 +/- 6.1% (p < 0.01) and 0.22 +/- 0.18% (p < 0.01) respectively after the induction and cultivation. It is concluded that the major action of this induction and cultivation method on T-lymphocytes in vitro is the promotion of CTL and NK T-cell proliferation. In leukemic patients at the remission stage, the TCRBV profile is characterized by the oligoclonal proliferation of T-lymphocytes. Several proliferated clones may have the same motif in CDR3, suggesting the recognition of the same antigen by these lymphocyte clones. Cytokine induction and co-culture with autogenous DCs can stimulate the T-lymphocytes to recover their immunocompetence as manifested by the polyclonal profile and the proliferation of CTL and NK-T cells.

This study was purposed to investigate the effect of rapamycin on proliferation, apoptosis, cell cycle progression and the regulation of chemokine receptor CXCR4 on RPMI8226 cells. Different concentrations of rapamycin were used to treat the multiple myeloma cell line RPMI8226 for different times. The proliferation of the cells was detected by MTT assay; the apoptosis rate and cell cycle were determined by flow cytometry (FCM); apoptosis of cells was observed by inverted microscopy; the cylin D1, CXCR4 and mTOR mRNA expressions were detected by RT-PCR or FQ-PCR after treating RPMI8226 cells with different concentrations of rapamycin. The results indicated that the rapamycin could inhibit the proliferation of RPMI8226 cells and induce their apoptosis. The cell cycle was arrested at the G(0)/G(1) phase. PCR results showed the down-regulation of mTOR, cyclin D1 and mTOR mRNA expressions after treating RPMI8226 cells with different concentrations of rapamycin for 24 hours. It is concluded that the rapamycin significantly inhibits the growth of RPMI8226 cells in a dose-and time-dependent mannes and induce cell apoptosis. Cell cycle arrests at the G(0)/G(1) phase, may be due to the down-regulation of the mTOR and cyclin D1 expressions. In additions, the down-regulation of CXCR4 mRNA expression is correlated with the reduction of adhesion between myeloma cells and stromal cells.

The aim of this study was to evaluate whether human placenta CD133(+) cells have an ability to reconstitute long-term hematopoiesis. Magnetic-activated cell sorting (MACS) was applied to enrich human placental CD133(+) cells. The isolated human placental CD133(+)cells of four different densities were established by limiting-dilution assay and primary fetal bone marrow stromal cells separated from bone marrow as feeder layer cells were co-cultured in long-term culture system so as to observe the incidence of long-term culture initiating-cells (LTC-IC) and their ability of proliferation and differentiation.The results showed that human placenta derived CD133(+) cells contained LTC-IC with frequency of 1/645 which have an ability to proliferate and differentiate into granulocyte/macrophage colony-forming units (CFU-GM) and mixed colony-forming units (CFU-Mix). In all LTC-IC positive wells, 71.43% form only CFU-GM and 28.57% display both CFU-GM and CFU-Mix formation. It is concluded that human placental CD133(+) cells possess LTC-IC with colony-forming capacity of hematopoietic early progenitor cells.

To study the expansion potentiality of megakaryocyte progenitor cells (MPCs) derived from human umbilical cord blood CD133(+) (UCB-CD133(+)) cells and determine the optimal harvest time. UCB-CD133(+) cells were purified from mononuclear cells (MNCs) by magnetic activated cell sorting (MACS) and seeded in serum-free liquid culture medium supplemented with thrombopoietin (TPO), interleukin-3 (IL-3), and stem cell factor (SCF) to expand MPCs. At day 0, 6, 10 and 14 of culture, the total cell number was counted and the dynamic changes of CD133, CD34, and CD41 antigen expression during ex vivo expansion were analyzed by flow cytometry (FCM). At different expansion times, the CD133(+) cells were collected and cultured in collagen semisolid medium to carry out CFU-MK colony culture. The incidence of CFU-MK was calculated and the morphology of MPCs and CFU-MK were detected by immunohistochemistry and Wright-Giemsa staining. The results showed that UCB-CD133(+) cells optimally expanded at day 7 with expansion multiple of 8.2 +/- 2.2 in serum-free liquid culture systems and the total cell number was expanded by 116-fold at day 14. At 10 days, each UCB-CD133(+) cell can form 2.5 +/- 1.0, 2.6 +/- 0.5 and 20.3 +/- 5.9 cells of CD133(+)CD41(+), CD34(+)CD41(+) and CD41(+) respectively, from which the number of CD133(+)CD41(+) and CD34(+)CD41(+) cells reach the highest. UCB-CD133(+) cells both before and after expansion could form CFU-MK, the total number of CFU-MK reached the peak from cells of 10 days expansion of UCB-CD133(+) cells and the expansion multiple of CFU-MK was 59.5 +/- 11.8. Immunohistochemical results indicated that the expanded megakaryocytic cells were immature and no sign of platelet formation. It is concluded that the human UCB-CD133(+) cells have a high ability of MPC expansion, 10 days of culture can be result in optimal expansion effect.

The aim of this study was to establish the standard protocols for isolating and enriching hematopoietic stem/progenitor cells (HSPC) from human placenta tissue (PT). Single-cell suspension from of human PT was prepared by mechanical method combined with collagenase digestion. Mononucleated cells (MNC) derived from PT were separated by hydroxyethyl starch (6% HES), then the three cell subsets of different immunophenotypes (CD34(-), CD34(+)CD38(-), CD34(+)CD38(+)) contained in MNC were isolated by Magnetic Activated Cell Sorting (MACS). The cell immunophenotype of each sorting steps was analyzed by flow cytometer (FCM). The cell enrichment and recovery rate of each sorting step were calculated. The results showed that MNC could be harvested up to (12.30 +/- 3.51) x 10(8) from a single-cell suspension of human PT by mechanical method and collagenase digestion, no significant difference existed as compared with umbilical cord blood (UCB) initial sample [(8.86 +/- 5.38) x 10(8)], but the percentage of CD34(+) cells in MNC of human PT was (3.93 +/- 2.31)%, much higher than that in UCB [(0.44 +/- 0.29)%] (P < 0.001). recovery rate of MNC and CD34(+) cells from PT after separation with 6% HES were (45.3 +/- 11.7)% and (51.1 +/- 9.8)%, respectively. After MNC being sorted by MACS, the enrichment and recovery rate of CD34(+) cells in CD34(+) group were (73.4 +/- 14.1)% and (52.7 +/- 11.7)% respectively. It is concluded that the protocols established here for isolating and enriching hematopoietic stem/progenitor cells from human placenta can acquire HSPC with high abundance, enrichment and viability and may be a useful reference of isolating methods for future related study.

The aim of this study was to investigate the clinical feasibility of adult stem cell transplantation for lethal mono-gene inherited disease, Duchenne muscular dystrophy (DMD). A total of 30 blood samples from DMD patients were genotyped with HLA-A,-B and -DR alleles by means of polymerase chain reaction-reverse sequence specific oligonucleotide (PCR-RSSO). The HLA gene types in 30 DMD patients were compared with those of 668 unrelated donors from Umbilical Cord Blood Center of Guangdong Province and 34 910 unrelated donors from Chinese Bone Marrow Bank. The results showed that HLA gene of the DMD group was inherited in normal distribution. There was no striking difference of HLA-A, -B and -DR alleles expression between the DMD patients group and control healthy group. 25% of the DMD patients got suitable donors for stem cell transplantation, in which 15 patients found donors with >or= 5/6 HLA match at the Umbilical Cord Blood Center of Guangdong Province, i.e. occupying 50% of the total. Eight patients got 6/6 HLA matching donors at the Chinese Bone Marrow Bank, i.e. occupying 26% of the total. It is concluded that stem cells transplantation therapy for DMD patients is feasible, which will benefit these patients suffered from the lethal neuromuscular disease, and create a new way to treat this tough nervous system disease.

Recently, a mitochondrial ceramidase has been identified and cloned, whose mitochondrial localization strongly suggests the existence of an unexpected mitochondrial pathway of ceramide metabolism that may play a key role in mitochondrial functions, especially in the regulation of apoptosis. To explore the biological effect of mitochondrial ceramidase on cells, pcDNA 3.1/His-CDase plasmid, containing mitochondrial ceramidase cDNA sequence, was transducted into K562 cells mediated by liposome, and G418 was used to screen for positive colonies. A stable transfected K562 cell line was established and named as 'K562TC'. The difference between K562 and K562TC cells in chemotheraputic cytotoxicity response and serum-withdrawal resistance and Bcl-2 protein expression were evaluated by MTT assay, annexin V/PI test, flow cytometry or Western blotting, respectively. The results showed that although survival was comparable between K562 and K562TC cells after exposed to adriamycin, etoposide or arsenious acid, K562TC cells with elevated Bcl-2 protein expression level as identified by FCM or Western blotting revealed stronger resistance to apoptosis induced by serum withdrawal than their parental cells. Inhibition of mitochondrial ceramidase expression in K562TC cells by its specific antisense oligodeoxynucleotide was correlated with a decrease in Bcl-2 protein level. N, N-dimethylsphingosine, a sphingosine kinase inhibitor, depleted intracellular sphingosine-1-phosphate production, also abrogated Bcl-2 protein expression in K562TC cells, while Bcl-2 protein level in K562 cells was up-regulated by exogenous sphingosine-1-phosphate. It is concluded that mitochondrial ceramidase overexpression in K562 cells leads to markedly elevated level of Bcl-2 protein and results in more resistance to serum withdrawal. This effect is initiated not by sphingosine, the direct metabolite of mitochondrial ceramidase, but via sphingosine-1-phosphate, its phosphorylated form. This is the first evidence that mitochondrial ceramidase, through its sphingoid metabolite sphingosine-1-phosphate, up-regulates Bcl-2 protein expression in K562 cells.

The SH2 domain containing inositol 5'-phosphatase (SHIP) was initially described as a 145 kD protein phosphorylated on tyrosines upon growth factor and cytokine stimulation. SHIP is predominately expressed in hematopoietic cells, and is a crucial negative regulator in the development of hematopoietic cells. To evaluate the role of the SHIP gene in human leukemogenesis, expression and mutation of SHIP gene in bone marrow and/or peripheral blood from 32 patients with acute myeloid leukemia (AML), 9 patients with acute lymphoblastic leukemia (ALL), as well as human hematopoietic cell lines were analyzed by reverse transcription-polymerase chain reaction (RT-PCR), single strand conformational polymorphism (SSCP) and sequencing. The RT-PCR showed that all samples expressed SHIP gene. Mutations of SHIP gene were detected in 7 out of 32 AML patients (22%) and one out of 9 ALL patients (12%). Interestingly, two missense mutations that had been observed in one AML patient at diagnosis disappeared after complete remission (CR). In addition, Akt phosphorylation was prolonged and increased following IL-3 stimulation in this patient sample. In conclusion, data of this study demonstrate the mutation of the SHIP gene in acute leukemia for the first time and suggest a possible role of the mutation of this gene in the development of acute leukemia. SHIP serves as a tumor suppressor by negatively regulating the PI3K/Akt signaling pathway in hematopoietic cells.

In order to investigate the anti-tumor activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors and the mechanism underlying the cell proliferation and apoptosis modulated in myeloma cells, the effects of mevastatin, an HMG-CoA reductase inhibitor, on cell growth, cell cycle progression and apoptosis in U266 human multiple myeloma (MM) cell line in vitro were explored by MTT colorimetric assay, morphologic observation, flow cytometry, DNA gel electrophoresis, and RT-PCR. The results demonstrated that mevastatin inhibited the growth of U266 cells in time- and dose-dependent manners. Cell cycle analysis showed that U266 cells underwent G(0)/G(1) arrest under exposure to mevastatin, but it did not affect p27 expression at both mRNA and protein level. Morphologic observations revealed cytoplasm shrinkage, nuclear condensation and fragmentation in mevastatin-treated cells, and fraction of annexin V(+)PI(-) cells increased significantly in the presence of the agent as determined by flow cytometric assay. In addition, mevastatin caused the collapse of mitochondrial transmembrane potential (Deltapsim), induced DNA fragmentation, and down-regulated the mRNA expression of bcl-2. The growth-inhibitory, cell cycle arresting, and proapoptotic effects of mevastatin in U266 cells could be effectively reversed by the addition of mevalonate (MVA), the immediate endproduct of the reaction catalyzed by HMG-CoA reductase. It is concluded that mevastatin suppresses proliferation by inducing G(0)/G(1) phase arrest and triggering apoptosis via down-regulation of bcl-2 and reduction of Deltapsim, which may be attributed to the inhibition of MVA pathway by mevastatin. Statins including mevastatin may find their future application in the treatment of MM.

The hematopoietic cell phosphatase (HCP or SHP-1), the SH2 domain contain protein tyrosine phosphatase, is a crucial negative regulator in the process of hematopoietic cell development, proliferation and receptor-mediated mitogenic signaling pathways, and its mutation is responsible for the over-expansion and inappropriate activation of myelomonocytic population in motheaten mice. The aim of the study was to evaluate the role of the HCP gene in leukemogenesis. Bone marrow and/or peripheral blood from 32 acute myeloid leukemia (AML) patients, 9 acute lymphocytic leukemia (ALL) patients, 8 leukemia cell lines and 50 normal controls were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) based on single strand conformation polymorphism (SSCP) and sequencing. RT-PCR showed that all samples expressed HCP gene, only one missense mutation at codon 225 (AAC to AGC, Asn to Ser) within N-terminal SH2 domain was found in an ALL patient. In addition, four polymorphic base substitutions were detected in codon 69, 85, 86 and 266, respectively. In conclusion, mutation of HCP gene is an infrequent genetic aberration which may only play a role in pathogenesis of a small part of leukemia, however, its significance needs to be further clarified.

Detection of the PML/RARalpha fusion gene by RT-PCR in acute promyelocytic leukemia (APL) blasts is not only critical to commence promptly the specific therapy with all-trans retinoic acid (ATRA) or arsenic trioxide (As(2)O(3)), but also essential for the definition of PML breakpoint type and subsequent monitoring of minimal residual disease (MRD). The current PML/RARalpha amplification techniques with conventional nested PCR are laborious and time consuming, which fails to meet the requirements for rapid diagnosis of APL in clinical practice. Therefore, an easily handled RT-PCR methodology for the rapid and accurate amplification of PML/RARalpha fusion transcripts is needed. A modified one round RT-PCR protocol was described with a few variations which includes rapid extraction of high quality cellular total RNA, cDNA synthesis with random hexamer and M-MLV reverse transcriptase, optimal concentrations of MgCl(2) (1 mmol/L), PCR primers (0.4 micro mol/L) and Taq polymerase (0.01 U/ micro l), hot-start procedure, and concomitant amplification of PML/RARalpha fusion gene and RARalpha internal control under the identical thermocycle parameters. The results in 40 patients with newly diagnosed APL showed that the improved RT-PCR protocol allowed the rapid detection of PML/RARalpha fusion gene and the accurate discrimination of its transcript types, and simultaneous amplification of RARalpha internal control under the identical program in less than 6 hours. There were no false positive or negative results found with the assay. In conclusion, the assay reported here is proved to be a simple, easily handled, and highly specific procedure for the diagnosis of APL cases, particularly those requiring such urgent therapeutic intervention as ATRA or As(2)O(3) and meriting its further application in APL management.

The aim of this study was to investigate whether and how phosphodiesterase (PDE) inhibitors modulate the proliferation, cell cycle and apoptosis in lymphoma cells. The effects of aminophylline (AM), a non-specific PDE inhibitor, on Raji cells were explored in vitro. MTT assay, light and transmission electron microscopy and annexin V staining were used to observe cell proliferation, morphologic changes and apoptosis rate in AM-treated cells, and FCM and RT-PCR techniques were adopted to detect the effect on cell cycle, the expression of cyclin B1 and Bcl-2 and mitochondrial transmembrane potential in AM-treated cells. The results showed that AM inhibited the growth of Raji cells in a concentration-dependent manner. Morphologic observations showed apoptosis changes in AM-treated cells, including cytoplamic shrinkage, cytoplasmic bubbling, karyopyknosis and nuclear fragmentation. FCM and RT-PCR detection showed that AM intervention increased the fraction of annexin V(+) cells, reduced the value of mitochondrial transmembrane potential, induced S phase arrest, and down-regulated the expression of Bcl-2 at both mRNA and protein level and cyclin B1 protein in a concentration-dependent manner. It is concluded that PDE inhibitor aminophylline may induce Raji cell growth inhibition, S phase arrest, apoptosis via down-regulation of Bcl-2 and reduction of mitochondrial transmembrane potential.

In order to investigate the role and the mechanism of protein tyrosine phosphatase (PTPase) signaling pathway in the regulation of proliferation, cell cycle and apoptosis in lymphoma cells, the effects of sodium orthovanadate, Na(3)VO(4), a specific PTPase inhibitor, were explored on Raji lymphoblast-like cell line by MTT assay and CFU-Raji culture, morphologic observation, DNA gel electrophoresis, FCM and RT-PCR. Results showed that MTT assay and CFU-Raji culture demonstrated that sodium or thovanadate inhibited the growth of Raji cells in a concentration-dependent fashion; morphologic observations showed that Raji cells exhibited cytoplasm shrinkage, cytoplasm membrane blebbing, nuclear fragmentation and chromatin condensation forming crescents along nuclear membrane characteristic of apoptosis in the presence of Na(3)VO(4); DNA gel electrophoresis revealed typical DNA ladder reminiscent of DNA cleavage at internucleosomal sites in Na(3)VO(4) treated cells; FCM and RT-PCR indicated that Na(3)VO(4) intervention increased the fraction of annexin V(+) PI(-) cells, reduced the value of mitochondrial transmembrane potential, induced G(2)/M arrest and down-regulated the expression of Bcl-2 and cyclin B1 at both mRNA and protein level in a concentration-dependent manner. It was concluded that PTPase pathway might be implicated in the regulation of cell proliferation, cell cycle and apoptosis, and PTPase specific inhibitor Na(3)VO(4) could induce Raji cell growth inhibition, G(2)/M arrest and apoptosis via down-regulation of Bcl-2 and cyclin B1, and reduction of mitochondrial transmembrane potential.