目的 探讨冬凌草甲素通过内质网应激诱导胰腺癌细胞凋亡的机制。方法 选取胰腺癌SW1990和Panc-1细胞株作为研究对象。采用细胞计数试剂-8（cell counting kit-8，CCK-8）和流式细胞术分别检测细胞增殖和凋亡情况，蛋白印迹法检测内质网应激相关因子葡萄糖调节蛋白78（glucose regulated protein 78 kD，GRP78）、环磷酸腺苷反应元件结合转录因子同源蛋白（C/EBP-homologous protein，CHOP）、裂解的天冬氨酸特异性半胱氨酸蛋白水解酶-12（cleaved cystein aspartate specific proteinase-12，cleaved Caspase-12）、活化的（active）Caspase-3、cleaved Caspase-3、cleaved多腺苷二磷酸多聚酶[poly (ADP-ribose) polymerase，PARP]的蛋白表达水平，实时荧光定量RCR检测GRP78、CHOP、Caspase-12的mRNA表达水平。结果 冬凌草甲素浓度和时间相关性抑制SW1990和Panc-1细胞增殖，冬凌草甲素可诱导SW1990和Panc-1细胞凋亡，可增加SW1990细胞中cleaved Caspase-3和cleaved PARP的蛋白表达水平（P＜0.05）；进一步研究发现冬凌草甲素能上调GRP78、CHOP、Caspase-12 mRNA及GRP78、CHOP、cleaved Caspase-12的蛋白表达水平，与对照组相比差异均有统计学意义（P＜0.05）。且在内质网应激抑制剂4-PBA的作用下，冬凌草甲素处理后细胞凋亡率和GRP78、CHOP、cleaved Caspase-12、active Caspase-3蛋白表达水平均被逆转，差异有统计学意义（P＜0.05）。结论 冬凌草素对SW1990和Panc-1细胞的促凋亡作用依赖于内质网应激的激活，冬凌草甲素可通过激活内质网应激介导胰腺癌细胞凋亡，为冬凌草甲素治疗胰腺癌中的抗肿瘤活性研究提供了新的思路。

Objective To investigate the mechanism of oridonin inducing apoptosis of pancreatic cancer cells through endoplasmic reticulum stress.Methods Pancreatic cancer SW1990 and Panc-1 cell line were selected as the research object. Cell proliferation and apoptosis were detected by cell counting kit-8 (CCK-8) and flow cytometry respectively. The protein expression levels of endoplasmic reticulum stress-related factors glucose regulated protein 78 kD (GRP78), C/EBP-homologous protein (CHOP), cleaved cystein aspartate specific proteinase-12 (Caspase-12), active Caspase-3, cleaved Caspase-3, and cleaved poly (ADP-ribose) polymerase (PARP) were analyzed by Western blotting. The mRNA expression levels of GRP78, CHOP and Caspase-12 were detected by RT-qPCR. Results The proliferation of SW1990 and PANG-1 cells was inhibited by oridonin concentration and time correlation. The apoptosis of SW1990 and Panc-1 cells was induced and protein expression levels of cleaved caspase-3 and cleaved PARP in SW1990 cells increased by oridonin (P < 0.05). Further studies showed that oridonin up-regulated mRNA expression levels of GRP78, CHOP and Caspase-12, as well as protein expression levels of GRP78, CHOP and cleaved Caspase-12, compared with the control group, the difference was statistically significant (P < 0.05). And under the action of endoplasmic reticulum stress inhibitor 4-PBA, apoptosis rate and protein expression levels of GRP78, CHOP, cleaved Caspase-12 and active Caspase-3 were all reversed after treatment with oridonin, the difference was statistically significant (P < 0.05). Conclusion The pro-apoptotic effects of oridonin on SW1990 and Panc-1 cells are dependent on the activation of endoplasmic reticulum stress. Oridonin can mediate the apoptosis of pancreatic cancer cells by activating endoplasmic reticulum stress, which provides a new idea for the anti-tumor activity of oridonin in pancreatic cancer.

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浙江省基础公益研究计划项目(LGD19H160006);浙江省医药卫生科技计划项目(2018KY614)