目的 研究半枝莲总黄酮（TF-SB）对人胃腺癌细胞AGS增殖、凋亡和放疗敏感性的影响和分子机制。方法 采用细胞计数试剂盒（CCK-8）法检测TF-SB（0、25、50、100、200 μg·mL⁻¹）作用24 h对AGS细胞存活率的影响。将AGS细胞分为对照组、溶剂对照（含相同浓度的甲醇）组、TF-SB（100 μg·mL⁻¹）组、质粒空载体（pcDNA，200 nmol·L⁻¹）组、迁移侵袭抑制蛋白（MIIP）过表达质粒（pcDNA-MIIP，200 nmol·L⁻¹）组、TF-SB（100 μg·mL⁻¹）＋小干扰RNA对照（si-con，200 nmol·L⁻¹）组、TF-SB（100 μg·mL⁻¹）＋MIIP小干扰RNA（si-MIIP，200 nmol·L⁻¹）组，转染质粒后TF-SB处理24 h，CCK-8法检测细胞存活率；流式细胞术检测细胞凋亡；Western blotting法检测B细胞淋巴瘤-xl（Bcl-xl）、裂解的半胱氨酸天冬氨酸蛋白酶（cleaved Caspase-3）、MIIP表达；不同照射量X射线（0、2、4、6、8 Gy）照射后，克隆形成实验检测细胞存活率，并绘制单击多靶模型拟合曲线，Western blotting法检测γ-H2AX蛋白表达。结果 与TF-SB 0 μg·mL⁻¹组比较，TFSB 25、50、100、200 μg·mL⁻¹组AGS细胞存活率显著降低（P＜0.05）；与对照组及溶剂对照组比较，TF-SB 100 μg·mL⁻¹组AGS细胞凋亡率显著升高（P＜0.05），Bcl-xl蛋白表达显著降低（P＜ 0.05），cleaved Caspase-3和MIIP蛋白表达显著升高（P＜0.05）；放疗后，TF-SB组细胞存活率显著降低（P＜0.05），γ-H2AX蛋白表达显著升高（P＜0.05），放疗敏感性增加。与pcDNA组比较，pcDNA-MIIP组AGS细胞凋亡率显著增加，细胞存活率显著降低，Bcl-xl蛋白表达显著降低，cleavedCaspase-3蛋白表达增加（P＜0.05）；放疗后，pcDNA-MIIP组细胞存活率显著降低（P＜0.05），γ-H2AX蛋白表达显著升高（P＜0.05），敏感性增加。与TF-SB＋si-con组比较，TF-SB＋si-MIIP组AGS细胞凋亡率显著降低，细胞存活率显著增加，Bcl-xl蛋白表达显著增加，cleaved Caspase-3蛋白表达显著降低（P＜0.05）；放疗后，TF-SB＋si-MIIP组细胞存活率显著升高（P＜0.05），γ-H2AX蛋白表达显著降低（P＜0.05），敏感性降低。结论 TF-SB通过上调MIIP可抑制AGS细胞增殖，诱导细胞凋亡，提高其放疗敏感性。

Objective To investigate the effect and molecular mechanism of total flavonoids of Scutellaria barbata (TF-SB) on the proliferation, apoptosis and radiosensitivity of gastric cancer cell AGS. Methods The cell counting kit (CCK-8) method was used to detect the effects of different concentrations (0, 25, 50, 100, 200 μg·mL⁻¹) of TF-SB on the survival of gastric cancer cells to determine the experimental concentration. AGS was divided into control group, solvent control group (methanol), TF-SB (100 μg·mL⁻¹), pcDNA (200 nmol·L⁻¹), pcDNA-MIIP (200 nmol·L⁻¹), TF-SB (100 μg·mL⁻¹) + si-con (200 nmol·L⁻¹), TF-SB (100 μg·mL⁻¹) + siMIIP (200 nmol·L⁻¹) group. Cell viability was detected by CCK-8 method. Flow cytometry was used to detect apoptosis. Clone formation test was used to detect the cell survival fraction after irradiation with different rays, and a one-click multi-target model was fitted to fit the curve. Western blotting was used to detect B cell lymphoma-xl (Bcl-xl), cleaved Caspase-3, migration invasion inhibitor protein (MIIP), γ -H2AX protein expression. Results Compared with TF-SB 0 μg·mL⁻¹ group, the survival rate of AGS cells in TF-SB 25, 50, 100 and 200 μg·mL⁻¹ groups was significantly decreased (P < 0.05). Compared with control group and solvent control group, the apoptosis rate of AGS cells in TF-SB 100 μg·mL⁻¹ group was significantly increased (P < 0.05), the expression of Bcl-XL protein was significantly decreased (P < 0.05), and the expression of Cleaved Caspase-3 and MIIP protein was significantly increased (P < 0.05). After radiotherapy, cell survival rate of TF-SB group was significantly decreased (P < 0.05), γ-H2AX protein expression was significantly increased (P < 0.05), and radiotherapy sensitivity was increased. Compared with the pcDNA group, the apoptosis rate of AGS cells in the pcDNA-MIIP group was significantly increased, the cell survival rate was significantly decreased, the expression of Bcl-XL protein was significantly decreased, and the expression of Cleaved Caspase-3 protein was increased (P < 0.05). After radiotherapy, the survival rate of pcDNA-MIIP group was significantly decreased (P < 0.05), the expression of γ-H2AX protein was significantly increased (P < 0.05), and the sensitivity was increased. Compared with TF-SB + si-con group, apoptosis rate of AGS cells in TF-SB + si-MIIP group was significantly decreased, cell survival rate was significantly increased, Bcl-XL protein expression was significantly increased, and Cleaved Caspase-3 protein expression was significantly decreased (P < 0.05). After radiotherapy, the survival rate of TF-SB + si-MIIP group was significantly increased (P < 0.05), the expression of γ -H2AX protein was significantly decreased (P < 0.05), and the sensitivity was decreased. Conclusions TF-SB could inhibit the proliferation of gastric cancer cell line AGS, induce apoptosis, and improve its radiotherapy sensitivity through up-reglating MIIP.

R285.5