摘要
背景:伊马替尼耐药是慢性髓细胞白血病治疗的一个主要问题,研究证实白血病细胞可通过与骨髓基质细胞黏附而获得耐药表型,但对于黏附功能缺陷的慢性髓细胞白血病而言,骨髓基质细胞在伊马替尼耐药形成中的作用及其机制尚不清楚。目的:体外模拟慢性髓细胞白血病患者骨髓微环境,探讨其对伊马替尼敏感性的影响及可能机制。方法:分离、培养确诊但未经治疗的慢性髓细胞白血病患者骨髓基质细胞,与白血病细胞株K562细胞共培养构建慢性髓细胞白血病骨髓基质细胞-K562细胞共培养模型。MTT法检测0.2-3.2μmol/L伊马替尼作用48 h对K562细胞的增殖抑制率;将K562细胞暴露于0.5μmol/L伊马替尼72 h,流式细胞术检测K562细胞凋亡率及CXCR4表达。将0.5μmol/L伊马替尼作用4 h并以Calcein-AM荧光标记的K562细胞接种于基质细胞层培养24 h,去除悬浮细胞,收集黏附的K452细胞通过检测荧光强度计算细胞黏附率。结果与结论:慢性髓细胞白血病骨髓基质细胞与K562细胞共培养减弱了0.2-3.2μmol/L伊马替尼对K562细胞的增殖抑制作用;0.5μmol/L伊马替尼处理72 h,共培养组K562细胞凋亡率显著低于悬浮组(P=0.020)。悬浮组和共培养组伊马替尼作用后K562细胞CXCR4表达阳性率均显著高于作用前(P=0.001)。0.5μmol/L伊马替尼作用4 h使K562细胞与骨髓基质细胞的黏附率由(32.18±6.17)%提升至(68.97±11.08)%,差异有显著性意义(P=0.022)。结果表明慢性髓细胞白血病患者骨髓基质细胞与K562细胞共培养,能介导对伊马替尼耐药,可能与共培养及伊马替尼诱导K562细胞CXCR4的表达有关,但更多的机制还需深入研究。
BACKGROUND: Imatinib resistance is a key issue in treatment of chronic myeloid leukemia. It is confirmed that the leukemia cells can obtain drug resistance phenotype mediated by adhesion to the bone marrow stromal cells(BMSCs). But, the role of BMSCs in imatinib resistance is unclear because chronic myeloid leukemia is deficient in adhesion function.OBJECTIVE: To in vitro simulate the bone marrow microenvironment of patients with chronic myeloid leukemia and to explore its influences on imatinib sensitivity as well as possible mechanisms.METHODS: BMSCs isolated from patients with chronic myeloid leukemia but not undergoing treatment were co-cultured with K562 cells to construct the BMSCs-K562 cell co-culture model in chronic myeloid leukemiapatients, then exposed to 0.2-3.2 μmol/L imatinib for 48 hours, and the proliferation inhibition rate of K562 cells was studied by MTT assay. The apoptosis rate of K562 cells and the expression of the CXCR4 in K562 cells exposed to0.5 μmol/L imatinib for 72 hours were detected by flow cytometry. The K562 cells were exposed to 0.5 μmol/L imatinib for4 hours and labeled by Calcein-AM fluorescent labeling sytem, and then, the adhesion rate of the K562 cells was calculated based on fluorescence intensity.RESULTS AND CONCLUSION: The suppressing effect of imatinib(0.2-3.2 μmol/L) on the proliferation of K562 cells was weakened significantly by co-culture with the bone marrow stromal cells from patients with chronic myeloid leukemia.The apoptosis rate of K562 cells exposed to 0.5 μmol/L imatinib for 72 hours in co-culture group was significantly lower than that in the suspension culture group(P=0.020). The positive rates of CXCR4 in the co-culture group and suspension culture groups were both increased after exposure to 0.5 μmol/L imatinib for 72 hours(P=0.001). The adhesion rate of the K562 cells to the BMSCs was elevated from(32.18±6.17)% to(68.97±11.08)% when the K562 cells were exposed to0.5 μmol/L imatinib for 4 hours, and the difference had statistical significance(P=0
出处
《中国组织工程研究》
CAS
北大核心
2015年第6期849-853,共5页
Chinese Journal of Tissue Engineering Research
基金
辽宁省科学技术计划重大
重点项目(2009225009-11)~~
