Inhibitory Effect of Curcumin on Proliferation of CD34(+) Acute Myeloid Leukemia Cells and Its Mechanism / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the inhibitory effect of curcumin on proliferation of CD34(+) acute myeloid leukemia cells and its mechamism.</p><p><b>METHODS</b>KG1a and Kasumi-1cell lines were treated with curcumin of different concentrations (0, 40, 60, 80 µmol/L). The effect of curcumin on cell viability and proliferation was detected by trypan blue staining and cell count. The effect of curcumin on distribution of NF-κB P65 subunit was analyzed by immunofluorescence and Western blot.</p><p><b>RESULTS</b>The curcumin inhibited proliferation of KG1a and Kasumi-1 cells in a dose-dependent manner. Western blotting showed that curcumin led to significant down-regulation of NF-κB P65 nuclear protein expression. Immunofluorescence assay showed that treatment with 40 µmol/L of curcumin for 48h suppressed the nuclear translocation of NF-κB p65 in KG1a and Kasumi-1 cells.</p><p><b>CONCLUSION</b>The curcumin suppresses cell growth of KG1a and Kasumi-1 cells, its mechanism may be related to inhibitory effect of curcumin on NF-κB p65 nucleus protein.</p>

Correlation of donor and recipient serum interleukin 2 and tumor necrosis factor alpha levels to acute graft-versus-host disease in hematopoietic stem cell transplantation / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the relationship between the donor and recipient serum interleukin 2 (IL-2) and tumor necrosis factor alpha (TNF-alpha) levels and the occurrence of acute graft-versus-host disease (aGVHD) following hematopoietic stem cell transplantation.</p><p><b>METHODS</b>Twenty-two leukemic patients undergoing allo-hematopoietic stem cells transplantation and their donors were examined for serum levels of IL-2 and TNF-alpha using ELISA during conditioning and after the transplantation. IL-2 and TNF-alpha levels were also detected in the donors during mobilization to analyze the relationship between the cytokines and aGVHD.</p><p><b>RESULTS</b>Five recipients showed no aGVHD, 10 developed grade I aGVHD, and 7 developed grade II-IV aGVHD. The serum levels of IL-2 and TNF-alpha after conditioning and post-transplantation were significantly higher in the recipients with grade II-IV aGVHD than in those with grade 0-I aGVHD, but no difference was found before the pre-conditioning. The serum IL-2 levels in the mobilized donors for the recipients with grade II-IV aGVHD were significantly higher than that in donors for recipients with grade 0-I aGVHD, whereas the levels of TNF-alpha showed no such a difference.</p><p><b>CONCLUSION</b>Serum IL-2 and TNF-alpha levels in the leukemic patients after conditioning and post-transplantation, and the donor serum IL-2 level after mobilization may be correlative to the severity of aGVHD and can be used as indicators for predicting the severity of aGVHD after the transplantation.</p>

In vitro study of cytotoxic T lymphocyte activation by antigen-loaded dendritic cells for killing of K562 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effect of dendritic cells (DC) stimulated with K562 cell lysate in inducing specific cytotoxic T lymphocytes (CTL) against K562 cells in vitro.</p><p><b>METHODS</b>The DCs were derived from healthy human peripheral blood monocytes in the presence of granulocyte-macrophage colony-stimulating factor, interleukin (IL)-4 and tumor necrosis factor (TNF) alpha. The T cells were stimulated by DCs loaded with freeze-thawed K562 cells and T-cell cytotoxicities were measured by lactate dehydrogenase (LDH) assay.</p><p><b>RESULTS</b>The DCs could be successfully obtained from peripheral blood monocyte after the culture. Mixed lymphocyte reactions induced by the antigen-loaded DC were much stronger than those induced by human peripheral blood monocytes (P<0.05). At the effector to target ratio of 10:1 and 20:1, cytotoxicities against K562 cells by CTL derived from culture with the antigen-loaded DCs were the strongest (P<0.05).</p><p><b>CONCLUSION</b>CTL derived from DCs pulsed with K562 cell lysate show effective and specific cytotoxicity against K562 cells.</p>

Anti-proliferation effect of oridonin on HL-60 cells and its mechanism / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism.</p><p><b>METHODS</b>HL-60 cells in vitro in culture medium were given different concentrations of oridonin. The inhibitory rate of cells were measured by microculture tetrazolium (MTT) assay, cell apoptotic rate was detected by flow cytometry (FCM), morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the activity of telomerase was detected using telomere repeat amplification protocol (TRAP) PCR-ELISA before and after apoptosis occurred.</p><p><b>RESULTS</b>Oridonin could decrease telomerase activity, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by hoechst 33258 fluorescence staining especially after cells were treated 48-60 hours by oridonin.</p><p><b>CONCLUSIONS</b>Oridonin has apparent anti-proliferation and apoptotic effects on HL-60 cells in vitro, decreasing telomerase activity of HL-60 cells may be one of its most important mechanisms. These results will provide strong laboratory evidence of oridonin for clinical treatment of acute leukemia.</p>