抗坏血酸对骨髓增生异常综合征细胞的抑制作用及相关机制

Inhibitory Effect of Ascorbic Acid on Myelodysplastic Syndrome Cells and Its Mechanism

目的:观察抗坏血酸单药或与地西他滨联合用药对抑制骨髓增生异常综合征(MDS)肿瘤细胞的抑制作用,并探讨其相关机制。方法:用不同浓度抗坏血酸干预人MDS细胞系SKM-1和MUTZ-1,CCK-8法检测细胞增殖活性,流式细胞术检测细胞内活性氧和不稳定铁池水平、细胞周期及凋亡程度。分别设立对照组、抗坏血酸组、地西他滨单药组及二者联合用药组,检测细胞增殖活性和凋亡程度。结果:高剂量抗坏血酸可降低SKM-1和MUTZ-1细胞的增殖活力,且这种抑制增殖作用呈剂量依赖性(复相关系数R=0.886,p=0.000和复相关系数R=0.880,p=0.000);随着抗坏血酸浓度升高,SKM-1和MUTZ-1细胞内活性氧水平增高(r=0.816,r=0.942),停滞在G2期的细胞比例增多(r=0.970,p=0.000;r=0.962,p=0.000),存活细胞比例减少(r=-0.966,p=0.000;r=-0.952,p=0.000),凋亡细胞明显增多(r=0.966,p=0.000;r=0.958,p=0.000),而不稳定铁池未见显著增高。抗坏血酸与地西他滨联合用药后,MDS肿瘤细胞较抗坏血酸和地西他滨单药组增殖活性下降,凋亡增多。结论:高剂量抗坏血酸对MDS肿瘤细胞存在细胞毒作用,抑制细胞增殖并增加其凋亡;抗坏血酸与地西他滨有协同抗MDS肿瘤细胞的作用。

Objective: To investigate the inhibitory effect of ascorbic acid single or combination of decitabine on tumor cells of myelodysplastic syndrome(MDS) and explore its related mechanism. Methods: The human MDS cell lines SKM-1 and MUTZ-1 were treated with different concentrations of ascorbic acid, and the cell proliferation activity was detected by the CCK-8 assay. The reactive oxygen species(ROS) level, labile iron pool(LIP), cell cycle, and apoptosis of SKM-1 and MUTZ-1 cells were detected by flow cytometry. The control group, ascorbic acid monotherapy group, decitabine monotherapy group, and combination group of ascorbic acid and decitabine were set up, the cell proliferation activity and apoptosis were detected in each group. Results: High-dose ascorbic acid could reduce the cell proliferation activity of SKM-1(R=0.886, p=0.000) and MUTZ-1(R=0.880, p=0.000). With the increase of ascorbic acid concentration, the ROS level in SKM-1 and MUTZ-1 cells increased(r=0.816, r=0.942), the proportion of cells stagnation in G2 phase increased(r=0.970, p=0.000;r=0.962, p=0.000), the proportion of surviving cells decreased(r=-0.966,p=0.000;r=-0.952, p=0.000), and the apoptosis cells significantly increased(r=0.966, p=0.000;r=0.958, p=0.000).Nevertheless, the level of LIP showed no significant changes. After the combined application of ascorbic acid and decitabine, MDS tumor cells showed decreased proliferative activity and increased apoptosis compared with single-agent ascorbic acid and decitabine group. Conclusion: High-dose ascorbic acid shows a cytotoxic effect on MDS tumor cells,inhibiting cell proliferation and increasing apoptosis. Ascorbic acid combined decitabine have a synergistic effect of antiMDS tumor cells.