盐酸小檗碱通过激活EMT促进小鼠乳腺癌肺转移的作用机制

Berberine Promotes Mouse Breast Cancer Metastasis to Lung via Inducing Epithelial–mesenchymal Transition

目的从上皮-间质转化(EMT)途径探讨盐酸小檗碱(BBR)对小鼠乳腺癌肺转移的作用及机制。方法CCK-8法检测BBR对乳腺癌4T1细胞增殖的影响;Transwell实验检测BBR对4T1细胞迁移的影响;采用第4对乳腺脂肪垫注射4T1-Luc细胞法建立小鼠乳腺癌模型,造模小鼠随机分为Control组和BBR组。BBR组小鼠连续腹腔注射BBR工作液,Control组小鼠连续腹腔注射同体积的用于溶解小檗碱粉末的溶剂。通过小动物活体成像系统检测活体小鼠肺部肿瘤转移情况。给药后第42天进行取材,通过显微镜观察HE染色小鼠肺转移情况;Western blot检测BBR对EMT相关蛋白(Vimentin、Snail)以及Akt和ERK信号通路表达的影响。结果BBR促进4T1细胞迁移(P<0.05);体内实验中,与Control组相比,BBR组小鼠的肺转移结节数量明显增多(P<0.05),镜下观察与HE染色结果一致;BBR上调EMT标志分子Vimentin和Snail及通路相关蛋白p-Akt和p-ERK在肿瘤组织中的表达水平,与Control组相比差异均有统计学意义(P<0.05)。结论BBR可能通过激活p-Akt和p-ERK通路蛋白表达,促进4T1乳腺癌细胞上皮-间质转化和肺转移。

Objective To study the effect and mechanism of berberine(BBR)on the lung metastasis of mouse breast cancer via epithelial–mesenchymal transition(EMT).Methods CCK-8 and Transwell migration assays were utilized to investigate the proliferation and migration properties of breast cancer 4T1 cells after BBR treatment.Mouse 4T1-Luc cells were injected into mice under the fourth mammary fat pad,and the mice were then randomly divided into the control and BBR groups.The mice in the BBR group received daily intraperitoneal injections of BBR working solution and those in the control group were continuously intraperitoneally injected with the same volume of the solvent used to dissolve BBR powder.Tumor metastasis in the lungs of living mice was detected by using an in vivo imaging system.After 42 days of administration,lung metastasis was measured via microscopy and HE staining.Western blot analysis was used to examine the effects of BBR on the expression of EMT-related proteins(Vimentin and Snail)as well as the activation of the Akt and ERK signaling pathways.Results BBR significantly promoted 4T1 cell migration(P<0.05).In vivo experiments showed that the number of lung metastases in the BBR group had significantly increased compared with that in control group(P<0.05)as observed under microcopy and histological staining.Compared with the control group,BBR upregulated the expression levels of Vimentin and Snail as well as the phosphorylated levels of p-Akt and p-ERK(P<0.05).Conclusion BBR may promote EMT and lung metastasis of breast cancer 4T1 cells by activating the expression of proteins in the p-Akt and p-ERK pathways.