目的 探讨重楼皂苷Ⅰ（PPI）对慢性髓系白血病细胞（K562）细胞的抑制作用及可能的作用机制。方法 采用CCK-8法筛选药物最适浓度,将培养时间为24 h的药物最适浓度作为后续实验的干预浓度。分组如下：（1）空白组;（2）PPI组;（3）抑制剂组;（4）PPI+抑制剂组。采用CCK-8法检测细胞增殖率;AO/EB染色观察细胞形态;流式细胞术检测凋亡率;ROS检测试剂盒检测活性氧（ROS）含量、还原型谷胱甘肽含量检测试剂盒检测谷胱甘肽（GSH）含量、细胞亚铁比色法测试盒检测细胞亚铁（Fe²⁺）含量;qRT-PCR法和蛋白免疫印迹法检测各组肿瘤蛋白53（p53）、钠氯离子依赖性氨基酸转运蛋白11（SLC7A11）、谷胱甘肽过氧化物酶4（GPX4）mRNA及蛋白表达量。结果 PPI抑制K562细胞的生长,且呈一定的剂量及时间依赖性（与同时间段的对照组0μmol/L比较,均P<0.01）。与空白组相比,PPI抑制K562细胞的增殖,提高了凋亡率,而铁死亡抑制剂（Ferrostian-1）的使用逆转了PPI对K562凋亡的促进作用（P<0.01）。与空白组相比,PPI组ROS、Fe²⁺含量升高,GSH含量下降,而铁死亡抑制剂的使用可下调ROS、Fe²⁺,上调GSH的含量（P<0.01）。PPI组较空白组p53 mRNA和蛋白表达水平升高,而SLC7A11、GPX4 mRNA和蛋白表达水平下降（P<0.05）;PPI+抑制剂组细胞较重楼皂苷组p53 mRNA和蛋白表达水平下降,而SLC7A11、GPX4 mRNA和蛋白表达水平升高（P<0.05）。结论 PPI能够有效抑制K562细胞增殖,促进K562细胞铁死亡,其分子机制可能与p53信号通路的调控有关。

Objective To investigate the inhibitory effect of polyphyllin I（PPI）on chronic myeloid leukemia cells（K562）and its possible mechanism．Methods K562 cell line was cultured in suitable environment,and the optimal concentration of the drug was screened by CCK-8 method．The optimal concentration of the drug cultured for 24 hours was used as the intervention concentration of the follow-up experiment．Cells were divided into the following groups：（1）blank group,（2）saponins group,（3）inhibitor group and（4）saponins + inhibitor group．The cell proliferation rate was detected by CCK-8 method．The cell morphology was observed by AO/EB staining．The apoptosis rate was detected by flow cytometry．The contents of reactive oxygen species（ROS）,glutathione（GSH）and ferrous（Fe²⁺）in different groups were detected,and the expression of mRNA and protein in different groups were detected by qRT- PCR and Western blot respectively．Results PPI significantly inhibited the growth of K562 cells in a dose-and time-dependent manner．Compared with the blank group,PPI significantly inhibited the proliferation of K562 cells and increased the apoptosis rate of K562 cells,while the use of ferroptosis inhibitor（Ferrostian-1）reversed the promoting effect of PPI on apoptosis of K562 cells．Compared with the blank group,the contents of reactive oxygen species（ROS）and ferrous iron（Fe²⁺）increased and the content of glutathione（GSH）decreased in the saponins group．The use of Ferrostian-1 could down-regulate the contents of ROS and Fe²⁺ and increase the content of GSH in the cells treated with the drug．Compared with the blank group,the expression of p53 mRNA and protein in the saponins group increased,while the expression of SLC7A11,GPX4 mRNA and protein decreased．The expression of p53 mRNA and protein in the saponins + inhibitor group was lower than that in the saponins group,while the expression levels of SLC7A11,GPX4 mRNA and protein increased．Conclusions PPI can effectively inhibit the proliferation of K562 cells and promote ferroptosis in K562 cells．The molecular mechanism can be related to the regulation of p53 signal pathway．

目的 比较一线伊马替尼疗效欠佳的慢性髓性白血病慢性期(CML-CP)患者,继续伊马替尼原方案或转换为尼洛替尼治疗后的疗效及安全性。方法 收集伊马替尼疗效欠佳的 45 例患者,分为伊马替尼组22例及尼洛替尼转换组23例,22例伊马替尼组患者继续接受原方案伊马替尼治疗,剂量均为400 mg qd,又将尼洛替尼转换组分为早期尼洛替尼转换组7例,晚期尼洛替尼组转换有16例。尼洛替尼转换组的23例患者接受尼洛替尼的剂量均为400 mg,q12h。所有入组患者首诊时测定 Sokal 评分,在治疗过程中随访观察定期监测血液学、细胞遗传学及分子学缓解情况(FISH 和 RQ-PCR),并对患者用药后的基本情况、临床表现及不良反应进行记录。结果 转换尼罗替尼治疗3个月时,早期尼洛替尼转换组中国际标准化 BCR-ABL1融合基因转录本水平(BCR-ABL1^IS)＜10%的患者有 5 例(71.4%),晚期尼洛替尼转换组BCR-ABL1^IS＜10%的患者有6例(37.5%),差异无统计学意义(P＞0.05)。中位观察6(3～12)个月,尼罗替尼组中有17例(73.9%)获得部分细胞遗传学反应,9例(39.1%)患者获得主要分子学反应。伊马替尼组中有9例(40.9%)获得部分细胞遗传学反应,2例(9.1%)患者获得主要分子学反应,尼洛替尼组部分细胞遗传学反应、主要分子学反应患者优于伊马替尼组(P值分别为0.027、0.020)。45例患者中达到完全细胞遗传学反应的患者与未达到完全细胞遗传学反应相比,Sokal 评分偏低(P=0.032)。结论 尼洛替尼可使伊马替尼疗效欠佳的 CML-CP 患者达到更好的疗效,因此需要及时对伊马替尼疗效欠佳的 CML-CP 患者进行评估后及时更换为尼洛替尼等二代酪氨酸激酶抑制剂。

Objective To assess the clinical efficacy and safety of original scheme or switching to nilotinib in patients with chronic myeloid leukemia in chronic phase(CML-CP)with suboptimal response of first-line imatinib. Methods 45 patients with suboptimal response of imatinib were collected and divided into 22 patients who continued to use original scheme and 23 patients who switched to nilotinib therapy. All the 22 patients of imatinib group received imatinib 400 mg once a day. And the 23 patients of nilotinib group were divided into early switch group and late switch group. Early switch group had 7 patients, late switch group had 16 patients. Both early and late switch to nilotinib group were subsequently to nilotinib 400 mg q12h. Sokal scores of all the enrolled patients were measured at the first diagnosis. Hematology, cytogenetics and molecular remission (FISH and RQ-PCR)were monitored, and the patients' basic information, clinical manifestations and adverse reactions were recorded regularly during the treatment. Results After switching to nilotinib for 3 months,there were 5 patients (71.4%)whose BCR-ABL1^IS<10% in the early nilotinib switch group, while 6 patients (37.5%)in the late nilotenib switch group.There was no statistical difference(P>0.05).With a median observation period of 6(3～12)months,there were 17 (73.9%)patients achieved partial cytogenetic response and 9 (39.1%)patients achieved major molecular response in the nilotinib group,there were 9 patients (40.9%)achieved partial cytogenetic response and 2 patients (9.1%)achieved major molecular response in the imatinib group. Patients who achieved partial cytogenetic response and major molecular response in the nilotinib group were more than those in the imatinib group (P values were 0.027 and 0.020, respectively).Sokal scores of 45 patients who had achieved complete cytogenetic response were lower than those who had achieved it (P=0.032). Conclusion Early switch to nitotinib is feasible and effective to patients who didn't have optimal response to imatinib. It is necessary to assess patients regularly in order to have the proper timing switching patients to nilotinib therapy.

       目的  探讨重楼皂苷Ⅰ（PPI）对慢性髓系白血病细胞（K562）细胞的抑制作用及可能的作用机制。方法  采用CCK-8法筛选药物最适浓度，将培养时间为24 h的药物最适浓度作为后续实验的干预浓度。分组如下：（1）空白组；（2）PPI组；（3）抑制剂组；（4）PPI+抑制剂组。采用CCK-8法检测细胞增殖率；AO/EB染色观察细胞形态；流式细胞术检测凋亡率；ROS检测试剂盒检测活性氧（ROS）含量、还原型谷胱甘肽含量检测试剂盒检测谷胱甘肽（GSH）含量、细胞亚铁比色法测试盒检测细胞亚铁（Fe²⁺）含量；qRT-PCR法和蛋白免疫印迹法检测各组肿瘤蛋白53（p53）、钠氯离子依赖性氨基酸转运蛋白11（SLC7A11）、谷胱甘肽过氧化物酶4（GPX4）mRNA及蛋白表达量。结果  PPI抑制K562细胞的生长，且呈一定的剂量及时间依赖性（与同时间段的对照组0μmol/L比较，均P＜0.01）。与空白组相比，PPI抑制K562细胞的增殖，提高了凋亡率，而铁死亡抑制剂（Ferrostian-1）的使用逆转了PPI对K562凋亡的促进作用（P＜0.01）。与空白组相比，PPI组ROS、Fe²⁺含量升高，GSH含量下降，而铁死亡抑制剂的使用可下调ROS、Fe²⁺，上调GSH的含量（P＜0.01）。PPI组较空白组p53 mRNA和蛋白表达水平升高，而SLC7A11、GPX4 mRNA和蛋白表达水平下降（P＜0.05）；PPI+抑制剂组细胞较重楼皂苷组p53 mRNA和蛋白表达水平下降，而SLC7A11、GPX4 mRNA和蛋白表达水平升高（P＜0.05）。结论  PPI能够有效抑制K562细胞增殖，促进K562细胞铁死亡，其分子机制可能与p53信号通路的调控有关。

       Objective  To investigate the inhibitory effect of polyphyllin I（PPI）on chronic myeloid leukemia cells（K562）and its possible mechanism．Methods  K562 cell line was cultured in suitable environment，and the optimal concentration of the drug was screened by CCK-8 method．The optimal concentration of the drug cultured for 24 hours was used as the intervention concentration of the follow-up experiment．Cells were divided into the following groups：（1）blank group，（2）saponins group，（3）inhibitor group and（4）saponins + inhibitor group．The cell proliferation rate was detected by CCK-8 method．The cell morphology was observed by AO/EB staining．The apoptosis rate was detected by flow cytometry．The contents of  reactive oxygen species（ROS），glutathione（GSH）and ferrous（Fe²⁺）in different groups were detected，and the expression of mRNA and protein in different groups were detected by qRT- PCR and Western blot respectively．Results  PPI significantly inhibited the growth of K562 cells in a dose-and time-dependent manner．Compared with the blank group，PPI significantly inhibited the proliferation of K562 cells and increased the apoptosis rate of K562 cells，while the use of ferroptosis inhibitor（Ferrostian-1）reversed the promoting effect of PPI on apoptosis of K562 cells．Compared with the blank group，the contents of reactive oxygen species（ROS）and ferrous iron（Fe²⁺）increased and the content of glutathione（GSH）decreased in the saponins group．The use of Ferrostian-1 could down-regulate the contents of ROS and Fe²⁺ and increase the content of GSH in the cells treated with the drug．Compared with the blank group，the expression of p53 mRNA and protein in the saponins group increased，while the expression of SLC7A11，GPX4 mRNA and protein decreased．The expression of p53 mRNA and protein in the saponins + inhibitor group was lower than that in the saponins group，while the expression levels of SLC7A11，GPX4 mRNA and protein increased．Conclusions  PPI can effectively inhibit the proliferation of K562 cells and promote ferroptosis in K562 cells．The molecular mechanism can be related to the regulation of p53 signal pathway．