目的：研究姜黄素衍生物C085对K562细胞增殖、凋亡的影响,并探讨其作用机制。方法采用 MTT 法观察C085对细胞增殖的影响；Annexin V-FITC/PI双荧光染色后流式细胞仪检测C085对细胞凋亡的影响；蛋白免疫印迹探讨C085引发K562细胞凋亡的机制,检测其对BCR-ABL及其下游信号转导通路蛋白的磷酸化及对其他凋亡相关蛋白表达的影响；JC-1荧光染色法检测C085对细胞线粒体膜电位的影响。结果 C085在低浓度下抑制K562细胞,IC50只有其母体姜黄素的1/5甚至更低；在24h即对K62细胞有较强的诱导凋亡作用,主要是中、晚期凋亡。与阳性对照药IM相比,诱导凋亡作用明显。对其作用机制研究发现,C085可下调BCR-ABL的自磷酸化和下游信号转导通路蛋白Stat 5和Crkl的磷酸化水平,作用均强于IM。 JC-1荧光染色法结果表明,C085通过直接作用于线粒体的PT孔使其开放,下调Bcl-2、上调Bax,诱导细胞凋亡,促凋亡作用强于IM。结论 C085可抑制 BCR-ABL+ K562细胞的生长,与其抑制BCR-ABL蛋白激酶活性,下调相关信号通路；直接作用于线粒体的PT孔使其开放,激活凋亡相关蛋白,诱导细胞凋亡有关。%Aim To explore the anti-proliferation and apoptotic effects of C085, a curcumin derivative, on K562 cells and its mechanism. Methods MTT assay and flow cytometry were used to examine cell prolifera-tion and apoptosis, respectively. The phosphorylation levels of Bcr-Abl initiated signaling proteins were ana-lyzed using Western blot. Results The results showed that C085 suppressed the growth of K562 cells and the IC50 value was about 5-fold lower than that of Cur. C085 also induced significant apoptosis on K562 cells in 24 hours when compared with imatinib. Western blot results demonstrated that C085 down-regulated the phosphorylation of Bcr-Abl in K562 cells in a dose-de-pendent manner. The phosphorylation of Stat 5 and Crkl, which were downstream signaling proteins of Bcr-Abl kinase, was also inhibited by C085. C085 caused the opening of mitochondrial PT holes as detected by JC-1 fluorescent, which inhibited Bcl-2 and enhanced Bax , then induced apoptosis. Conclusion C085 in-hibited BCR-ABL+ K562 cells through inhibiting BCR-ABL kinase activity and down-regulating its down-stream signal proteins. Directly acting on mitochondrial PT hole and then activating apoptosis- associated pro-teins are also involved in the pro-apoptotic effect of C085 .
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