吲哚美辛抑制髓系白血病细胞增殖机制的研究

Proliferation inhibition effect of indomethacin on CML cells associated with down regulation of phosphorylated STAT1/STAT5 and inhibition of COX-2 expression

目的 探讨吲哚美辛 (IN)抗慢性髓系白血病 (CML)细胞增殖的作用机制。方法 用MTT法分析IN对慢性髓系白血病细胞系K5 6 2及CML患者骨髓细胞活力的影响 ;Westernblot分析CML细胞信号转导和转录活化蛋白 (STAT) 1、STAT5表达 ;免疫共沉淀 /Westernblot分析IN干预后CML细胞磷酸化的STAT1(p STAT1)和STAT5 (p STAT5 )表达 ,间接免疫荧光技术观察p STAT1和p STAT5在CML细胞中的分布及变化 ;Westernblot检测IN干预前后Bcl XL 及环氧化酶 2 (COX 2 )蛋白的表达。结果 IN可显著抑制CML细胞活力 ;4 0 0 μmol/LIN作用 72h ,CML细胞抑制率为 86 % ;0～ 4 0 0 μmol/LIN呈剂量反应性抑制p STAT1、p STAT5表达 ;p STAT主要呈散点状分布于胞核中 ;Bcl XL 蛋白呈IN浓度依赖性表达下调 ;K5 6 2细胞存在COX 2蛋白表达 ,IN可抑制COX 2蛋白表达。结论 IN可明显抑制CML细胞增殖 ;其机制可能与药物抑制STAT/Bcl XL 信号转导途径有关 ;K5 6 2细胞存在COX 2蛋白表达 ,IN的抗白血病细胞增殖效应可能是通过COX 2依赖性途径实现的。

Objective To explore the mechanism of anti proliferative effect of indomethacin(IN) on chronic myelogenous leukemia (CML) cells. Methods MTT was applied to assay CML cells viability under IN intervention. STAT1, STAT5 proteins were analyzed by Western blot, the expressions of phosphorylated STAT1 or STAT5 by immunoprecipitation combined with Western blot, the cellular localization of p STATs proteins by indirect immunofluorescence technique, and the detection of Bcl X L and COX 2 protein by Western blot. Results IN could significantly inhibit the viability of CML cells. 0～400 μmol/L of IN could down regulate the expression of p STAT1 or p STAT5 in a dose response manner, p STATs were distributed mainly in the nucleus as scattering spots. The expression of COX 2 protein could be detected in K562 cells. Both Bcl X L and COX 2 proteins could be inhibited by IN in a dose dependent manner. Conclusions IN could significantly inhibit the proliferation of CML cells, the mechanism of which might be related to the suppression of STATs/Bcl X L signal transdution pathway. There exists COX 2 protein expression in K562 cells, the anti leukemia effect of IN was possibly dependent on COX 2 pathway.