益气补肾方下调胃癌干细胞表面标志物表达抗肿瘤增殖转移的实验研究

Experimental Study of Inhibiting Effect of Proliferation and Metastasis of Gastric Cancer by Yiqi Bushen Formula Through Down- Regulating Expression of Surface Markers of Cancer Stem Cell

目的:探讨益气补肾方对人胃癌裸鼠原位移植瘤生长转移的影响及作用机制,为临床应用提供实验依据。方法:以人胃癌细胞株NCI-N87为对象,建立胃癌干细胞(cancer stem cells,CSC)富集裸鼠荷瘤模型。40只裸鼠随机分为生理盐水组(NS组)、氟尿嘧啶组(5-Fu组)、益气补肾方组(中药组)及益气补肾方+5-Fu组(中药+5-Fu组)。药物干预4周,观察分析各组裸鼠体重变化,移植瘤生长变化以及转移率;采用免疫组化法检测各组肿瘤组织中CD24、CD44、上皮细胞黏附分子(Epithelial cell adhesion molecule,Ep CAM)的表达差异。结果:5-Fu组、中药组、中药+Fu组裸鼠体重明显重于NS组(P<0.05),且中药组与5-Fu组、中药+5-Fu组相比差异有统计学差异(P<0.05);各组裸鼠均未见明显转移灶;5-Fu组、中药组、中药+5-Fu组的瘤体大小均小于NS组(P<0.05)。中药组和中药+5-Fu组CD24、CD44的表达以及中药组Ep CAM的表达均低于NS组及5-Fu组的表达,差异有统计学意义(P<0.05)。结论:益气补肾方具有显著的抗胃癌细胞增殖的作用,同时能减少荷瘤裸鼠体重下降,其作用机制可能是通过下调CSC表面标志物CD24、CD44、Ep CAM的表达,降低瘤体内CSC表面标志物的比例,诱导胃癌CSC良性分化,最终发挥抗胃癌增殖转移的作用。

Objective： To study and explore the effect and mechanism of Yiqi Bushen Formula on the growth and metastasis of orthotopic transplantation human gastric carcinoma in nude mice,which can provide theoretical evidence for clinical application. Methods： The nude mice of human gastric carcinoma constructed using orthotopic transplantation and an enrichment in cancer stem cell of NCI- N87 gastric cancer cell line were randomized into four groups： saline control group,5- fluorouracil（ 5- Fu） group,Yiqi Bushen Formula group,combination group of Yiqi bushen Formula and 5-fluorouracil. After accepted 28 days of treatment,we observed and analyzed the changes in body weight of nude mice,the growth and change of the transplanted tumor,metastasis rate and inhibition rate of tumor and investigated the expressions of CD24,CD44,Ep CAM in tumor tissues that were detected with immunohistochemical method. Results： The average weight of 5- Fu group,Yiqi Bushen Formula group and combination group became significantly higher than those in saline control group（ P〈0. 05）. And there were statistical significant differences about average weight between Yiqi Bushen Formula group and the other two treatment groups（ P〈0. 05）. There was no significant metastasis focus in other organs of the nude mice. The mean size of tumor in three treatment groups were significantly lower than that in the saline control group（ P〈0. 05）. The expressions of CD24 and CD44 in Yiqi Bushen Formula group and combination group were found to be lower than those in saline control group and 5- Fu group. The positive Ep CAM expression rate of Yiqi Bushen For-mula group was apparently lower than that of the saline control group and 5- Fu group（ P〈0. 05）. Conclusion： Yiqi Bushen Formula could effectively inhibit the proliferation and metastasis of cancer cells,lessen the losses of body weight,which may be associated with down- regulating the expressions of CD24,CD44,Ep CAM in nude mice model,reducing the proportion of the gastric cancer stem cells surface markers in vivo and inducing benign differentiation of gastric cancer stem cell.