硼替佐米对慢性髓系白血病急变期原代细胞耐药的逆转作用及XIAP表达的影响

Effect of Bortezomib on Reverse Multidrug Resistance and XIAP Expression in Imatinib-resistant Primary Cells of Chronic Myeloid Leukemia in Blastic Crisis

本研究旨在探讨蛋白酶体抑制剂硼替佐米对伊马替尼耐药的慢性髓系白血病(CML)急变期原代细胞药物敏感性及X连锁凋亡抑制蛋白(XIAP)表达的影响。采用MTT法观察伊马替尼单用与联合硼替佐米对伊马替尼耐药的CML急变期原代细胞生长增殖的影响,流式细胞术检测细胞凋亡与P170糖蛋白的表达,实时荧光定量PCR检测XIAP基因表达。结果表明,伊马替尼及硼替佐米单药对单个核细胞均表现出抑制作用,且呈时间-剂量依赖;联合5、10 nmol/L硼替佐米能明显增强单个核细胞对伊马替尼的敏感性;流式细胞术检测显示硼替佐米作用后细胞凋亡明显增高,同时P170糖蛋白表达明显降低;实时荧光定量PCR检测显示,耐伊马替尼CML急变期原代细胞高表达XIAP基因,硼替佐米作用后其表达下调。结论:硼替佐米可抑制白血病原代细胞并提高其对伊马替尼的敏感性,硼替佐米可能通过抑制XIAP的表达从而增加凋亡,这为扩展硼替佐米在临床上治疗CML提供实验依据。

This study was aimed to explore the effects of proteasome inhibitor bortezomib on the drug sensitivity of imatinib-resistant primary cells in blastic phase of chronic myeloid leukemia（CML） and the expression of XIAP.MTT methsd was used to detect the inhibitory effect on cell growth,flow cytometry was used to assay the apoptosis and P170 expression,and RT-PCR was used to monitor the expression of XIAP mRNA.The results showed that the effect of imatinib or bortezomib alone showed an inhibitory effect on MNC in time-and dose-dependent manner;5 and 10 nmoL/L bortezomib combined with imatinib could significantly enhance the sensitivity of mononuclear cells to imatinib.The increase of apoptosis rate,and the decrease of P170 expression could be observed by flow cytometry during treatment with bortezomib.The over-expression of XIAP could be down regulated by bortezomib.It is concluded that the bortezomib could inhibit primary cells of leukemia and enhance sensitivity of CML primary cells to imatinib.The bortezomib may increase the cell apoptosis by inhibition of XIAP expression,so as to provide the experiment evidence to spread bortezomib for the clinical treatment of chronic myeloid leukemia.