Effects of Sinopodophyllum hexundrum on apoptosis in K562 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of Sinopodophyllum hexundrum on apoptosis in K562 cells.</p><p><b>METHODS</b>K562 cells were treated with Sinopodophyllum hexundrum at different concentrations and for different lengths of time to determine the optimal conditions of SinoPodophyllum hexandrum treatment for K562 cells using CCK8 assay. The cell apoptotic rate was detected by flow cytometry, and the cell morphology and nuclear morphology of K562 cells were observed with Wright staining and DPAI staining, respectively. The protein expressions of BCR/ABL, p-BCR/ABL, STAT5, p-STAT5 and the apoptosis-related proteins PARP, caspase-3 and cleaved-caspase-3 were determined with Western blotting.</p><p><b>RESULTS</b>The cell proliferation was inhibited in a concentration-and time-dependent manner by 1, 2, and 3 µg/mL Sinopodophyllum hexundrum. The treatment was optimal with a Sinopodophyllum hexundrum concentration of 2 µg/mL a treatment time of 48 h, and the cell apoptotic rate increased in a time-dependent manner and significantly increased at 48 h (P<0.001). The expression of apoptosis-related proteins PARP, caspase-3 and cleaved-caspase-3 were also activated in a time-dependent manner. The cells showed typical apoptotic changes after treatment with 2 µg/mL Sinopodophyllum hexundrum for 48 h with significantly reduced expressions of BCR/ABL, p-BCR/ABL, STAT5, AND p-STAT5.</p><p><b>CONCLUSION</b>Sinopodophyllum hexundrum promotes K562 cell apoptosis possibly by inhibiting BCR/ABL-STAT5 survival signal pathways and activating the mitochondrion-associated apoptotic pathways.</p>

Effect of Recombinant Adenovirus AdE-SH2-Caspase 8 on the Apoptosis of Imatinib-resistant K562/G01 Cell Line / 中国实验血液学杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULT</b>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.</p><p><b>CONCLUSION</b>The recombinant adenovirus SC expressing SH2-Caspase 8 fusion protein can induces the apoptosis of K562/G01 cells.</p>

Indomethacin Significantly Enhances Inhibitory Effect of Imatinib on Proliferation of KCL22 and K562/G01 Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>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.</p>