Study on the Mechanism of Multi-Drug Resistance of Agaricus Blazei Extract FA-2-b-β Mediated Wnt Signaling Pathway to Reverse Acute T Lymphoblastic Leukemia / 中国实验血液学杂志

OBJECTIVE@#To investigate the mechanism of drug reversing resistance of Agaricus blazei extract FA-2-b-β on T cell acute lymphoblastic leukemia (T-ALL) cell lines.@*METHODS@#Cell proliferation was detected by CCK-8 assay; the apoptosis, cell cycle mitochondrial membrane potential, and intracellular rhodamine accumulation were detected by flow cytometry, and apoptosis-related gene and protein expression were detected by qPCR and Western blot; the membrane surface protein MDR1 was observed by immunofluorescence microscopy.@*RESULTS@#Different concentrations of FA-2-b-β significantly inhibited proliferation and induced apoptosis of CCRF-CEM and CEM/C1 (P<0.05), and CCRF-CEM cell cycle were arrested at S phase, and CEM/C1 cells were arrested at G0/G1 phase. Western blot and qPCR results show that FA-2-b-β inhibited ABCB1、ABCG2、CTNNB、MYC and BCL-2 expression, but upregulated Bax expression. In addition, FA-2-b-β reversed the resistance characteristics of CEM/C1 drug-resistance cells, which decreased mitochondrial membrane potential, and significantly increased the intracellular rhodamine accumulation, and weakening of the expression of the membrane surface protein MDR1. With the Wnt/β-catenin inhibitor (ICG001), the process was further intensified.@*CONCLUSION@#Agaricus Blazei Extract FA-2-b-β inhibits cell proliferation, promotes apoptosis, regulates the cell cycle, reduces mitochondrial energy supply, and down-regulate MDR1 expression to reverse the resistance of CEM/C1, which all suggest it is through regulating the Wnt signaling pathway in T-ALL.

Effect of Curcumin on Apoptosis of Acute T-Lymphoblastic Leukemia Cells induced by UMI-77 and Its Related Mechanism / 中国实验血液学杂志

AbstractObjective: To explore the effect and mechanism of curcumin on human T-cell acute lymphoblastic leukemia (T-ALL) cell apoptosis induced by Mcl-1 small molecule inhibitors UMI-77.@*METHODS@#T-ALL cell line Molt-4 was cultured, and the cells were treated with different concentrations of curcumin and Mcl-1 small molecule inhibitor UMI-77 for 24 h. The MTT method was used to detect the cell survival rate after different treatment; According to the results of curcumin and UMI-77, the experimental settings were divided into control group, curcumin group (20 μmol/L curcumin treated cells), UMI-77 group (15 μmol/L Mcl-1 small molecule inhibitor UMI-77 treated cells) and curcumin+ UMI-77 group (20 μmol/L curcumin and 15 μmol/L Mcl-1 small molecule inhibitor UMI-77 treated cells), MTT method was used to detect cell proliferation inhibition rate, Annexin V-FITC/PI double staining method and TUNEL staining were used to detect cell apoptosis, DCFH-DA probe was used to detect cell reactive oxygen species, JC-1 fluorescent probe was used to detect mitochondrial membrane potential, Western blot was used to detect the expression levels of apoptosis-related proteins and Notch1 signaling pathway-related proteins.@*RESULTS@#After the treatment of Molt-4 cells with different concentrations of curcumin and Mcl-1 small molecule inhibitor UMI-77, the cell survival rate was decreased (P<0.05); Compared with the control group, the cell proliferation inhibition rate of the curcumin group and the UMI-77 group were increased, the apoptosis rate of cell was increased, the level of ROS was increased, the protein expression of Bax, Caspase-3 and Caspase-9 in the cells were all increased, and the protein expression of Bcl-2 was reduced (P<0.05); Compared with the curcumin group or UMI-77 group, the cell proliferation inhibition rate and apoptosis rate of the curcumin+UMI-77 group were further increased, and the level of ROS was increased. At the same time, the protein expression of Bax, Caspase-3 and Caspase-9 in the cells were all increased, the protein expression of Bcl-2 was reduced (P<0.05); In addition, the mitochondrial membrane potential of the cells after curcumin treatment was decreased, and the proteins expression of Notch1 and HES1 were reduced (P<0.05).@*CONCLUSION@#Curcumin can enhance the apoptosis of T-ALL cells induced by Mcl-1 small molecule inhibitor UMI-77 by reducing the mitochondrial membrane potential, the mechanism may be related to the inhibition of Notch1 signaling pathway.

Bortezomib and obatoclax for dual blockade of protein degradation pathways show synergistic anti-tumor effect in human acute T lymphoblastic leukemia cells / 南方医科大学学报

OBJECTIVE@#To explore whether bortezomib and a Bcl-2 inhibitor exhibit synergistic anti-tumor effect in human acute T lymphoblastic leukemia cells.@*METHODS@#MTT assay was used to determine the cytotoxicity of bortezomib in the absence or presence of Bcl-2 inhibitors (obatoclax, AT-101 and ABT-199) in Jurkat cells. The effects of drug treatment on the expression of Bcl-2 family proteins, LC3B, p62, ubiquitin, BiP/Grp78, p-JNK, p-p38 and CHOP proteins were examined by Western blotting. Flow cytometry was used to determine the effects of bortezomib and Bcl-2 inhibitors (obatoclax, AT-101 and ABT-199) on cell apoptosis. Quantitative real-time PCR was used to measure the mRNA expression levels of the key regulatory factors of unfolded protein reaction (UPR). A zebrafish xenograft model was used to study the anti-tumor effect of bortezomib, obatoclax and their combination in vivo.@*RESULTS@#Bortezomib or Bcl-2 inhibitors alone inhibited the cell viability of Jurkat cells, but only obatoclax and bortezomib showed synergistic cytotoxicity and pro-apoptotic effect. Obatoclax, rather than AT-101 and ABT- 199, blocked autophagic flux in the cells evidenced by concomitant accumulation of LC3B-Ⅱ and p62. Both bortezomib and obatoclax alone caused accumulation of polyubiquinated proteins, and their combination showed a synergistic effect, which was consistent with their synergistic cytotoxicity. The dual blockade of proteasome and autophagy by the combination of bortezomib and obatoclax triggered unfolded protein response followed by cell apoptosis. Preventing UPS dysfunction by tauroursodeoxycholic acid (TUDCA) significantly attenuated the cytotoxicity and pro-apoptotic effect of bortezomib in combination with obatoclax. In zebrafish xenograft models, bortezomib combined with obatoclax significantly decreased tumor foci formation.@*CONCLUSIONS@#Bortezomib and obatoclax for dual blockade of protein degradation pathways show synergistic anti-tumor effect in human acute T lymphoblastic leukemia cells.

Proteasome Inhibitor MG132 Inhibits Cell Proliferation and Induces Cell Apoptosis in Acute T Lymphoblastic Leukemia Cell Via FOXO3a/Puma Pathway / 中山大学学报(医学科学版)

[Objective]To explore the effect and the possible mechanism of the proteasome inhibitor MG132 on acute T lympho?blastic leukemia cells.[Methods]The influence of different concentrations of MG132 in the viability and proliferation of CCRF-CEM was measured by MTS. Apoptosis rates of CCRF-CEM treated by MG132 were determined by flow cytometry. After being exposed to MG132,the protein levels of FOXO3a in cytoplasm and nucleus were analyzed by Western blotting. qRT-PCR was applied to detect the mRNA of FOXO3a and Puma in cells treated by MG132. Then CCRF-CEM was stably transfected with antisense FOXO3a using Lentivirus infection. We further investigated the effects of MG132 in FOXO3a-shRNA cells and elucidated the mechanisms of FOXO3a and Puma.[Results]MG132 inhibits the proliferation of CCRF-CEM,but has no cytotoxicity in peripheral blood mononu?clear cells(PBMC). Cellular apoptosis was induced in cells treated with MG132. At mRNA level,MG132 had no influence on FOXO3a,but increased the expression of Puma. However,MG132 promoted the expression of both FOXO3a and Puma at protein level. Interestingly,the expression of FOXO3a increased very little in cytoplasm. In FOXO3a-shRNA cells the expression of FOXO3a and Puma decreased at protein level. FOXO3a's knockdown attenuated the proliferation inhibition mediated by MG132.[Conclusion]MG132 inhibits the proliferation and promotes to apoptosis of CCRF-CEM. One of the mechanism is that MG132 inhib? its the degradation of FOXO3a,and then activates FOXO3a/Puma pathway.