氯化镧对人白血病细胞系K562生长的影响

 目的 了解稀土氯化镧（LaCl3）对白血病细胞系K562生长和凋亡的影响，为临床应用LaCl3治疗白血病提供理论依据。方法 用MTT法鉴定LaCl3对K562细胞生长增生的影响；显微镜下观察细胞形态的变化，流式细胞术及TUNEL法鉴定细胞凋亡情况；流式细胞术分析细胞周期的变化。半固体琼脂糖培养法观察LaCl3对正常骨髓细胞形成粒－巨噬细胞集落的影响。结果 在所研究的浓度范围内，随着LaCl3浓度升高，K562细胞生长抑制率增高、凋亡率增加，呈剂量依赖性关系。随着作用时间延长，1 mmol／L LaCl3对细胞的抑制率增高、凋亡率增加，呈时间依赖性关系；K562细胞G0／G1期细胞百分率升高而S期细胞百分率下降。0.1及0.5 mmol／L LaCl3显示出对正常骨髓祖细胞有轻度刺激增生效果，而较高浓度（1.5～2.0 mmol／L），正常骨髓祖细胞形成集落数下降且含有较多巨噬细胞，集落细胞形态正常，没有显示凋亡形态。结论 在所研究浓度范围内，稀土LaCl3能抑制K562细胞生长并且诱导细胞凋亡，呈剂量及时间依赖性关系；但对正常骨髓造血细胞的影响还有待于进一步研究。

Effects of lanthanum chloride on growth and apoptosis of K562 leukemia cell lines

Objective To investigate the effects of rare earth compound (lanthanum chloride, LaCl3) on the growth and apoptosis of K562 cells. Methods To investigate the effects of LaCl3 on the growth of K562 cells by MTT assay, the apoptosis detected by flow cytometry and TUNEL method, the cell cycle of K562 cells treated with LaCl3, and analyzed by flow cytometry, to evaluate the hematopoietic ability of normal bone marrow cells treated by LaCl3 by counting the granulocyte-macrophage colonies. Results MTT assay showed that treatment with 0.1, 0.5, 1.0, 1.5 and 2.0 mmol/L LaCl3 for 24 h, 48 h and 72 h could inhibit the growth of K562 cells. Apoptosis could be detected on treatment with 0.1, 0.5, 1.0, 1.5 and 2.0 mmol/L LaCl3 for 48 h in K562 cells by light microscopy morphology examination, and flow cytometry analysis. 1.0mmol/L for 24 h, 48 h, 72 h and 96 h treatment with 1mmol/L LaCl3 could significantly induce K562 apoptosis by flow cytometry and TUNEL method. Treatment of 1 mmol/L LaCl3 could arrest the transitions of K562 cells from G0/G1 to S phase. The granulocyte-macrophage colony formation (CFU-GM) of normal bone marrow cells was not significantly inhibited in treatment with 0.05 and 1.0 mmol/L LaCl3, but slightly increased in 0.1 and 0.5 mmol/L. Treatment with higher concentrations (1.5 to 2.0 mmol/L LaCl3), the colony formation was significantly inhibited. Conclusion Our data demonstrate that LaCl3 (0.1 to 1.0 mmol/L) may inhibit K562 cell growth and induce them to apoptosis.