Effects of decitabine on proliferation and apoptosis of NB4 and K562 cells / 中国实验血液学杂志

This study was aimed to investigate the effects of decitabine (DAC) on proliferation and apoptosis of leukemia NB4 and K562 cells. The proliferation inhibition of DAC on NB4 and K562 cells was detected by Trypan blue staining. After treatment of DAC at different concentrations, the changes of cell cycle and CD11b expression was determined by flow cytometry. The cell morphological changes were observed by Wright's staining. The DNA ladder was used to detect cell apoptosis. The results indicated that DAC significantly inhibited the proliferation of NB4 and K562 cells in dose-and time-dependent manner. The median inhibitory concentration (IC50) of DAC-treated NB4 and K562 cells for 72 h was 0.113 µmol/L and 0.138 µmol/L, respectively. After treating these two cell lines with DAC at different concentration for 72 h, the cell ratio in G0/G1 phase significantly increased, while the cell ratio in S phase obviously decreased in 0.15 µmol/L DAC group (P < 0.05). The expression levels of myeloid differentiation antigen CD11b of both cell lines significantly increased in contrast to the control group (P < 0.05). The cell morphology detected by Wright's staining displayed partial differentiation and apoptosis after treating NB4 and K562 cells with DAC for 48 h. Typical apoptotic DNA ladder was observed in 0.15 µmol/L DAC group at 48 h. It is concluded that DAC can inhibit NB4 and K562 cell proliferation, induce cell differentiation and apoptosis, but more obviously for NB4 cells.

Differential proteomic analysis in human umbilical cord mesenchymal stem cells induced by cobalt chloride / 中华血液学杂志

<p><b>OBJECTIVE</b>To analyze the differential proteomics in human umbilical cord mesenchymal stem cells (MSC) induced by chemical hypoxia-mimetic agent cobalt chloride (CoCl(2)) by two-dimensional gel electrophoresis (2-DE) and mass-spectrometry.</p><p><b>METHODS</b>2-DE was performed to separate proteins from treated and untreated human umbilical cord MSC with CoCl(2). 2-DE images were analyzed by ImageMaster 2D Platinum software 6.0. The differential expressed proteins was identified by MALDI-TOF-MS. The differential proteins were classified based on their functions.</p><p><b>RESULTS</b>2-DE reference patterns of CoCl(2) treated human umbilical cord MSC were established. A total of twenty-six differential proteins were identified, of them eleven proteins were up-regulated and fifteen down-regulated. Their biological functions involved in carbohydrate metabolism, protein metabolism and modification, lipid metabolism, coenzyme and prosthetic group metabolism, cell cycle, immunity and defense, cell structure and motility, signal transduction, protein targeting and localization, neuronal activities, muscle contraction, etc. Peroxiredoxin1 (Prdx) was down-regulated, whereas alpha-enolase (ENO1) and vesicle amine transport protein 1 homolog (VAT1) up-regulated.</p><p><b>CONCLUSION</b>The effects of hypoxia on human umbilical cord MSC were participated by multiple proteins and involved in multiple functional pathways.</p>