[Effect of Chidamide on the Killing Acitivity of NK Cells Targeting K562 Cells and Its Related Mechanism In Vitro].

To investigate the effect of chidamide on the killing activity of NK (Natural killer cell, NK) cells targeting K562 cells and its related mechanism.K562 cells were pretreated with chidamide at different concentrations and cocultured with NK cells at different effect-target ratios. The killing effect of chidamide on K562 cells by NK cells, the expression of natural killer group 2 member D (NKG2D) ligands and apoptosis rate of K562 cells were detected by flow cytometry.The killing sensitivity of NK cells to K562 cells could be enhanced by chidamide. The expression of ULBP2 on K562 cell surface could be up-regulate, however, the expression of ULBP1 and MICA/MICB showed no statistically difference as compared with control group. Chidamide showed no obvious cytotoxicity to K562 cells.Chidamide can significantly improve killing efficiency of NK cells on K562 cells, which may be related to the up-regulation of ULBP2 expression.西达本胺对NK细胞体外杀伤K562细胞活性的影响及其相关机制.观察西达本胺对自然杀伤细胞（NK）体外杀伤K562细胞活性的影响并探讨其作用机制.用不同浓度的西达本胺预处理K562细胞，与NK细胞不同效靶比共同孵育，采用流式细胞术检测西达本胺作用于K562细胞后NK细胞对其杀伤作用、K562细胞表面NKG2D相关配体表达量及K562细胞凋亡率的变化.西达本胺可增加K562细胞对NK细胞杀伤的敏感性，同时可上调K562细胞表面ULBP2表达，对ULBP1、MICA/MICB表达无明显影响，西达本胺于K562细胞本身无明显细胞毒性作用.西达本胺可能通过增加ULBP2的表达提高K562细胞对NK细胞杀伤敏感性.