三氧化二砷诱导骨髓瘤细胞凋亡机制研究

摘要

目的了解三氧化二砷(As2O3) 诱导多发性骨髓瘤细胞（MM）凋亡的可能机制及其与维甲酸和干扰素的相互作用。方法联合应用As2O3和巯基还原剂（DTT）、谷胱甘肽耗竭剂（BSO）、全反式维甲酸（ATRA）或干扰素（IFN-α）处理MM细胞系RPMI8226和U266细胞；应用台盼蓝拒染法计数细胞活力，经细胞形态学和流式细胞仪等判定细胞凋亡的程度；通过测定细胞内荧光染料Rhodamine 123的色强度分析线粒体跨膜电位（ΔΨm）。结果 BSO可加强As2O3诱导的RPMI8226和U266细胞线粒体ΔΨm下降和凋亡，而DTT则有部分拮抗的作用。ATRA诱导RPMI8226细胞凋亡，但它和As2O3之间无协同效应。ATRA并不诱导U266细胞凋亡。此外，IFN-α既不抑制RPMI8226和U266细胞的生长和活力，也不改变As2O3对这些细胞的作用。结论 As2O3诱导多发性骨髓瘤细胞凋亡和巯基有关，但ATRA或干扰素和As2O3无协同效应。%Objective　To investigate the possible mechanisms of arsenic trioxide (As2O3)-induced apoptosis in multiple myeloma (MM) cell line, and the interactions between As2O3 and all-trans retinoic acid (ATRA) or interferon(IFN)-α.Methods　Multiple myeloma cell lines RPMI 8226 and U266 were treated with As2O3 in combination with dithiothreitol (DTT), buthionine sulfoximine (BSO), ATRA and IFN-α. Cell viability was counted by trypan-blue exclusion. Apoptosis was assessed by cell morphology and flow cytometry. Mitochondrial transmembrane potentials (ΔΨm) were measured by cellular rhodamine 123 staining intensity on flow cytometry.Results　Glutathione depleting agent BSO at 1.0 mmol/L enhanced, while disulfide bond-reducing agent DTT at 0.2 mmol/L partially antagonized As2O3-induced decline of ΔΨm and apoptosis in MM cells. ATRA also induced RPMI 8226 cell apoptosis, but it could not synergize with As2O3. On the other hand, As2O3-induced apoptosis did not occur in U266 cells. In addition, IFN-α itself did not inhibit the growth and viability of MM cells, nor did it influence the effects of As2O3 on MM cells.Conclusion　As2O3-induced apoptosis of RPMI 8226 multiple myeloma cells involves sulphyhydryl groups. ATRA and IFN-α do not synergize with As2O3 in the induction of apoptosis of MM cells.