AIM: To demonstrate the effects of telmisartan on the proliferation and apoptosis of U937 cells.METHODS: The proliferation ability of the U937 cells was assessed by CCK-8 assay and colony formation test with methylcellulose.The CD11b expression rate of the U937 cells was identified by flow cytometry.The apoptotic rate was analyzed by flow cytometry with Annexin V-PI double staining and Hoechst 33342 staining.The protein levels of cleaved PARP and cleaved caspase-3 were determined by Western blot.RESULTS: The results of CCK-8 assay confirmed that the viability of U937 cells was inhibited by telmisartan.The colony formation capacity of U937 cells was also significantly inhibited by telmisartan.The differentiation of U937 cells was induced by telmisartan with the expression of CD11b.The results of flow cytometry analysis with Annexin V-PI double staining and Hoechst 33342 staining identified that the apoptosis of U937 cells was induced by telmisartan in dose-dependent and time-dependent manners with the up-regulation of cleaved PARP and cleaved caspase-3 proteins.CONCLUSION: Telmisartan inhibits the proliferation and induces the differentiation of U937 cells.Telmisartan also induces the apoptosis of U937 cells through the caspase pathway.

BACKGROUND:Because of their immunological properties, bone marrow mesenchymal stem cells transfusion is developed as a new treatment for refractory graft-versus-host disease. OBJECTIVE:To analyze the safety and curative effect of bone marrow mesenchymal stem cells transfusion on treating different organ damages in graft-versus-host disease after al ogeneic hematopoietic stem celltransplantation. METHODS:Eight patients with malignant hematologic disease were included in this study. The patients developed severe steroid-resistant graft-versus-host disease after al ogeneic hematopoietic stem celltransplantation and received transfusion of mesenchymal stme cell(1×106 of immunosuppressive agent. RESULTS AND CONCLUSION:For the total y eight patients, six got response (two cases of complete remission, and four cases of partial remission) and two showed no remission. Four of five cutaneous damages were ameliorated and one showed no effect. For three cases of oral graft-versus-host disease, two acquired complete remission and one showed partial remission. Two cases of liver graft-versus-host disease and two cases of astro-intestinal graft-versus-host disease obtained complete remission. No response was displayed to three cases of ocular graft-versus-host disease, one case of bronchiolitis obliterans, and one case of urinary graft-versus-host disease. In the median fol ow-up of 28 months (7-62 months), three patients developed posttransplant lymphoproliferative disorders within 3 months after mesenchymal stem cells transfusion. Administration of mesenchymal stem cells is safe for treatment of severe graft-versus-host disease after al ogeneic hematopoietic stem celltransplantation. Mesenchymal stem cells transfusion may be a promising/kg) together with the primary therapy therapy for refractory cutaneous , astro-intestinal, liver and oral graft-versus-host disease but not for pulmonary, ocular and urinary graft-versus-host disease. Whether mesenchymal stem cells transfusion is associated with posttransplant lymphoproliferative disorders needs more case data.

AIM: To investigate the effect of c-Myc inhibitor 10058-F4 on human chronic myeloid leukemia ( CML) K562 cells and imatinib-resistant K562/G cells.METHODS: The protein expression of c-Myc was detected by Western blotting .Cell proliferation was evaluated by MTT assay and colony formation assay .PI staining was used to deter-mine the cell cycle distribution .Annexin V-PI staining was applied for apoptosis detection .RESULTS:Imatinib-resistant K562/G cells displayed lower sensitivity to imatinib than K 562 cells with high expression of c-Myc.Treatment with specific c-Myc inhibitor 10058-F4 inhibited the cell proliferation in a dose-and time-dependent manner , and K562/G displayed more sensitivity to 10058-F4 than K562 cells.10058-F4 also induced cell cycle arrest in G 0/G1 phase and induced apoptot-ic cell death in the 2 cells.Importantly, 10058-F4 suppressed the colony formation ability in K 562 and K562/G cells. CONCLUSION:c-Myc is a novel target to overcome imatinib-induced drug resistance , and c-Myc inhibitor provides a new approach in CML therapy .

Objective To investigate the anti-proliferation effect of peroxisome proliferator-activated receptor γ(PPARγ)agonist troglitazone(TGZ)on leukemic Raji cells and its mechanisms.Methods Raji cells in culture medium in vitro were given different concentrations of TGZ(0～60 μmol/L)for 24,48 and 72 h.The inhibitory rates of the cells were measured by MTT assay,cell apoptotic rate was detected by flow cytometry(FCM),agarose gel electrophoresis was used to observe the DNA ladder,and western blotting was used to analyzed the variation of apoptosis related proteins bcl-2,Bax and Survivin.Results TGZ(over 20 μmol/L)could inhibit the growth of Raji cells and cause apoptosis remarkably,the suppression was both in time-and dose-dependent manner.DNA ladder was observed after the cells treated by TGZ for 72 h,and western blotting analysis revealed that anti-apoptotie proteins Survivin and bcl-2 were decreased remarkably while pro-apoptotic protein Bax increased significantly after the cells were treated by TGZ for 48 h.Conclusion PPARγ agonist TGZ can inhibit the growth and induce apoptosis on Raji cells significantly,downregnlating the expression of Survivin and bcl-2 as well as upregulating of Bax expression of Raji cells may be one of its most important mechanisms.

AIM:To investigate the anti-tumor effects of special cytotoxic T lymphocytes(CTLs)activated by dendritic cells(DCs)loaded with antigens and CD40L in vitro.METHODS:Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation from normal human heparinized blood.The adherent cells were cultured with granulocyte-macrophage colony stimulating factor(GM-CSF),interleukin-4(IL-4),alpha tumor necrosis factor(TNF-?),DCs were co-cultured with frozen-thawed antigen of K562 cells and CD40L,then triggered T cells into specific CTLs.RESULTS:Most suspended cells exhibited distinctive morphological features of DCs which expressed CD40 96%,CD86 97%,CD80 77%,CD1a 69%,and gained the powerful capacity to stimulate proliferation of allogenic lymphocytes.Under the effector∶target ratio of 20∶1,CTLs derived from cultures with DCs and frozen-thawed antigen of K562 cells were showed 71.3% cytotoxicities against K562 cells.CTLs derived from cultures with DCs loaded with frozen-thawed antigen and CD40L were showed 86.9% cytotoxicities against K562 cells.Cytotoxicities by CTLs derived from cultures with unloaded DCs against K562 cells were 37.6% and cytotoxicities by monocytes were 21.1%.Cytotoxicities by CTLs derived from experiment groups were stronger than control groups(P

AIM: To investigate the effect of granulocyte colony stimulating factor (G-CSF) on arabinosyl cytosine (Ara-C)-induced apoptosis in HL-60 leukemia cells. METHODS: The proliferation of HL-60 leukemia cell was observed by hemopoietic cell culture. Apoptosis was measured by the morphology of apoptosis cell , the quantitation of DNA fragmentation with the diphenylamine reaction. The change in drug sensitivity was measured by “MTT”. RESULTS: G-CSF could stimulate the proliferation of HL-60 leukemia cell and colonies of cell increased to 76.5?18.0, compared to the control group (46.5?13.5. P

AIM: To study the effects of WT1 peptide-loaded dendritic cells (DC) stimulating the cytotoxic T lymphocytes (CTL) on K562 cells in vitro. METHODS: DC were generated from normal human peripheral blood mononuclear cells (PBMC) in the presence of granulocyte-macrophage colony stimulating factor(GM-CSF), interleukin-4 (IL-4) and tumor necrosis factor alpha (TNF-?) , DC were cultured with WT1 peptides , and then triggered T cells into specific CTL. RESULTS: Most suspended cells exhibited distinctive morphological features of DCs and they stimulated proliferation of allogenic lymphocytes. Under the effector : target ratio of ~20∶1 , CTLs derived from cultures with DC and WT1 peptides were showed 86.1%?26.8% cytotoxicity against K562 cells, cytotoxicity by CTLs derived from cultures with unloaded DC against K562 cells were 47.1%?20.8% and cytotoxicity by lymphocytes were 27.7%?15.3%. Cytotoxicity by CTLs derived from culture with WT1 peptides-loaded DC were the strongest among three groups (P

AIM: To investigate the changes of the expression of Bcl-2 and Fas protein and the apoptosis in HL-60 cells induced by cyclosporine A. METHODS: The expression of Bcl-2 and Fas protein and apoptosis in (HL-60) cells were measured by immunohistochemistry analysis and flow cytometric analysis. RESULTS: There was strong expression of Bcl-2 in HL-60 cells, treatment with cyclosporine A (CsA) for 8-10 h down-regulated the expression of Bcl-2. Fas protein expression in HL-60 cells was very low, CsA induced apoptosis of HL-60 cells, but didn't induce Fas protein expression. CONCLUSION: CsA induces apoptosis in HL-60 cells by down-regulating Bcl-2 expression. [

Objective To investigate the apoptosis inducing effect of peroxisome proliferator-activated receptor r(PPARr)agomst on leukemic K562 cells and its mechanisms of action.Methods K562 cells in culture medium in vitro were given different concentrations of PPARragonist rosiglitazone(RGZ)(20-80 umol/L)for O,24,48 and 72h The inhibitory rate of the cells were measured by MTT assay,cell apoptosis was detected by Annexin V/PI staining,and the expression of P53 protein as well as the activity of caspase-3 were also detected.Results RGZ(over 40umoL/L)could inhibit the growth of K562 cells and cause apopto-sis remarkably,the suppression Was both in time-and dose-dependent manner.The expression of P53 pmtein was upregulated and the activity of caspase-3 Was increased concomitantly after the cells werle treated by RGZ.Conclusion PPARr agonist RGZ(over 40 umol/L)can induce apoptosis on K562 cells signifieantly,upregu-lation the expression of P53 protein as well as increasing caspase-3 activity may be one of its most important mechamisms.

AIM: To detect the protein expression of TIMP3 and RUNX3 in bone marrow mononuclear cells (BMMCs) from acute leukemia (AL) patients and to investigate the relationship between the methylation status of genes and their expressional levels. METHODS: Protein expression of TIMP3 and RUNX3 in 50 samples of BMMCs and 10 samples of peripheral blood mononuclear cells (PBMCs) from healthy volunteers was detected by Western blotting. The prognostic factors related to AL and data from methylation specific polymerase chain reaction were also analyzed. RESULTS: The expression level of RUNX3 with methylation was less than that without methylation in BMMCs from AL patients. The complete remission (CR) rate was related to RUNX3 expression and blasts in bone marrow (BM). BMMCs from patients with silencing of RUNX3 and higher blasts in BM had a lower CR rate. CONCLUSION: Absence of RUNX3 protein expression resulting from methylation of RUNX3 promoter probably plays a role in the pathogenesis of AL and is of value in prognosis. No relationship between methylation of TIMP3 promoter and the pathogenesis of AL is observed.