[关键词]
[摘要]
目的 基于干扰素 γ(IFN-γ)/核因子 κB(NF-κB)/SNAIL 轴探讨复方蜥蜴散干预肿瘤细胞干性对胃癌顺 铂耐药的增敏提效作用机制。方法 (1)取对数生长期的 MKN45 细胞和 MKN45/DDP 耐药细胞,分别使用不同 浓度(0、0.2、0.4、0.8、1.6、3.2 μg·mL-1 )的顺铂(DDP)处理细胞 48 h,采用 CCK-8 法测定细胞增殖能力及耐 药指数。采用无血清悬浮成球实验验证 MKN45 细胞及 MKN45/DDP 耐药细胞的肿瘤干细胞特性。(2)将对数生 长期 MKN45/DDP 细胞接种于 BALB/c 雄性裸鼠右前腋窝皮下,复制胃癌顺铂耐药裸鼠移植瘤模型。将模型复 制成功的裸鼠随机分为模型组、顺铂组、复方蜥蜴散组及联合组,每组 8 只。模型组灌胃等体积生理盐水;顺 铂组腹腔注射 0.002 g·kg-1顺铂,每周 2 次;复方蜥蜴散组灌胃 2.8 g·kg-1复方蜥蜴散水煎液,每天 2 次;联合 组灌胃复方蜥蜴散水煎液(2.8 g·kg-1 ,每天 2 次)的同时腹腔注射顺铂(0.002 g·kg-1 ,每周 2 次);各组均连续干 预 4 周。称量肿瘤质量并计算肿瘤体积;采用 HE 染色法观察肿瘤组织病理变化;TUNEL 法测定肿瘤组织细 胞凋亡情况;免疫组化法检测肿瘤组织 Ki67、EpCAM、CD44 蛋白表达情况;Western Blot 法测定肿瘤组织多 药耐药相关蛋白 1(MRP1)、P-糖蛋白(P-gp)、EpCAM、CD44、IFN-γ、p65、p-p65、SNAIL 蛋白表达水 平。结果 (1)与 MKN45 细胞比较,0.8、1.6、3.2 μg·mL-1 顺铂组的 MKN45/DDP 耐药细胞存活率显著升高 (P<0.05,P<0.01);MKN45 细胞的 IC50为 0.96 μg·mL-1 ,MKN45/DDP 细胞的 IC50为 2.26 μg·mL-1 ,MKN45/DDP 细胞的耐药指数为 2.36。与 MKN45 细胞比较,MKN45/DDP 耐药细胞的成球能力显著升高(P<0.01)。(2)模型 组裸鼠的肿瘤细胞形态不规则,排列较紧密,细胞核大,可见病理性核分裂象。与模型组比较,各给药组胃癌 耐药 MKN45/DDP 细胞荷瘤裸鼠的肿瘤体积均显著缩小(P<0.01),肿瘤质量均显著降低(P<0.01);肿瘤细胞 核分裂现象减少,细胞密度降低,排列较松散,可见细胞坏死象;肿瘤细胞凋亡率均显著升高(P<0.01);肿 瘤组织中 Ki67 阳性表达水平显著降低(P<0.05,P<0.01);肿瘤组织中的干性标志物 EpCAM、CD44 及耐药 相关蛋白 MRP1、P-gp 的蛋白表达水平均显著降低(P<0.05,P<0.01);肿瘤组织 p-p65/p65、IFN-γ、SNAIL 蛋白表达水平均显著降低(P<0.01)。与顺铂组比较,复方蜥蜴散组及联合组胃癌耐药 MKN45/DDP 细胞荷瘤 裸鼠的肿瘤体积均显著缩小(P<0.01),肿瘤质量均显著降低(P<0.01);肿瘤细胞凋亡率均显著升高(P< 0.01);肿瘤组织中 Ki67 阳性表达水平显著降低(P<0.05,P<0.01),CD44、MRP1、P-gp、IFN-γ、SNAIL 蛋 白表达水平显著降低(P<0.05,P<0.01);联合组裸鼠肿瘤组织中 EpCAM、p-p65/p65 蛋白表达水平显著降低 (P<0.01)。结论 复方蜥蜴散能够有效抑制胃癌耐药 MKN45/DDP 细胞荷瘤裸鼠的肿瘤生长,抑制细肿瘤胞 增殖,促进其凋亡,可能与通过调控 IFN-γ/NF-κB/SNAIL 轴抑制肿瘤细胞干性,从而降低对顺铂的耐药性有关。
[Key word]
[Abstract]
Objective To investigate the mechanism by which Compound Xiyi San(CXS) enhances cisplatin sensitivity in gastric cancer by interfering with tumor stemness via the interferon-γ(IFN-γ)/nuclear factor-κB (NF-κB)/SNAIL axis. Methods (1) MKN45 cells and MKN45/DDP cisplatin-resistant cells in the logarithmic growth phase were treated with different concentrations (0,0.2,0.4,0.8,1.6,3.2 μg·mL-1 ) of cisplatin (DDP) for 48 hours. Cell proliferation capacity and the resistance index were measured using the CCK-8 assay. The cancer stem cell characteristics of MKN45 and MKN45/DDP cells were validated using the serum-free suspension sphere formation assay.(2) MKN45/DDP cells in the logarithmic growth phase were subcutaneously inoculated into the right anterior axilla of male BALB/c nude mice to establish a cisplatin-resistant gastric cancer xenograft model. Successfully modeled mice were randomly divided into four groups (n=8 per group):model group,cisplatin group,CXS group,and combination group. The model group received an equal volume of normal saline by gavage;the cisplatin group received intraperitoneal injections of 0.002 g·kg-1 cisplatin twice weekly;the CXS group received 2.8 g·kg-1 CXS aqueous extract by gavage twice daily;the combination group received both CXS aqueous extract (2.8 g·kg-1 ,twice daily) and cisplatin (0.002 g·kg-1 ,twice weekly). All interventions continued for 4 weeks. Tumor mass was weighed,and tumor volume was calculated. Pathological changes in tumor tissue were observed by HE staining;apoptosis was detected by TUNEL assay;protein expression of Ki67, EpCAM, and CD44 in tumor tissue was determined by immunohistochemistry; and protein expression levels of multidrug resistance-associated protein 1 (MRP1), P-glycoprotein (P-gp), EpCAM, CD44, IFN- γ, p65, phosphorylated p65(p-p65),and SNAIL were measured by Western Blot. Results (1) Compared with MKN45 cells, the survival rates of MKN45/DDP cells in the 0.8,1.6,and 3.2 μg·mL-1 cisplatin groups were significantly increased (P<0.05,P<0.01). The IC50 for MKN45 cells was 0.96 μg·mL-1 ,and for MKN45/DDP cells it was 2.26 μg·mL-1 , resulting in a resistance index of 2.36 for MKN45/DDP cells. Compared with MKN45 cells,MKN45/DDP cells exhibited a significantly enhanced sphere-forming ability (P<0.01).(2) In the model group, tumor cells showed irregular morphology,tight arrangement,large nuclei,and pathological mitotic figures. Compared with the model group,all treatment groups showed significantly reduced tumor volume (P<0.01) and tumor mass (P<0.01) in MKN45/DDP xenograft nude mice;mitotic figures were reduced,cell density decreased,arrangement became looser,and necrotic cells were observed;tumor cell apoptosis rates were significantly increased (P<0.01);Ki67 positive expression levels in tumor tissue were significantly decreased (P<0.05, P<0.01); protein expression levels of stemness markers EpCAM and CD44,and drug resistance-related proteins MRP1 and P-gp were significantly decreased (P<0.05,P< 0.01);and protein expression levels of p-p65/p65,IFN-γ,and SNAIL in tumor tissue were significantly decreased (P<0.01). Compared with the cisplatin group,the tumor volume and tumor mass of MKN45/DDP xenograft nude mice in the CXS group and the combination group were significantly reduced (P<0.01);significantly increased apoptosis rates (P<0.01); significantly decreased Ki67 positive expression (P<0.05, P<0.01), and significantly lower protein expression levels of CD44,MRP1,P-gp,IFN-γ,and SNAIL (P<0.05,P<0.01);the combination group also showed significantly decreased EpCAM and p-p65/p65 protein expression levels (P<0.01). Conclusion Compound Xiyi San effectively inhibits tumor growth,suppresses cell proliferation,and promotes apoptosis in nude mice bearing cisplatin-resistant MKN45/DDP gastric cancer xenografts. This effect may be related to the suppression of tumor stemness and subsequent reduction of cisplatin resistance through regulation of the IFN-γ/NF-κB/SNAIL axis.
[中图分类号]
R285.5
[基金项目]
国家自然科学基金项目(82260916);宁夏医科大学科学研究资助项目(XZ2023012)。