Epithelial mesenchymal transition (EMT) is a well-known and important step in metastasis and thus can be a key target in cancer treatment. Here, we tested the EMT inhibitory actions of Selaginella tamariscina and its active component, amentoflavone (AF). EMT was examined in vitro using wound-healing and invasion assays and by monitoring changes in the expression of the EMT-related proteins, E-cadherin, Snail, and Twist. Metastasis was examined in vivo using SCID mice injected with luciferase-labeled A549 cells. We confirmed that aqueous extracts of S. tamariscina (STE) and AF inhibited EMT in human cancer cell lines. We found that STE and AF at nontoxic concentrations exerted remarkable inhibitory effects on migration (wound healing assay) and invasion (Transwell assay) in tumor necrosis factor (TGF)-β-treated cancer cells. Western blotting and immunofluorescence imaging show that AF treatment also restored E-cadherin expression in these cells compared to cells treated with TGF-β only. Suppression of metastasis by AF was investigated by monitoring migration of tail-vein-injected, circulating A549-luc cells to the lungs in mice. After 3 wk, fewer nodules were observed in mice co-treated with AF compared with those treated with TGF-β only. Our findings indicate that STE and AF are promising EMT inhibitors and, ultimately, potentially potent antitumor agents.

中文翻译：

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卷柏卷柏的活性化合物金黄酮抑制体内和体外TGF-β诱导的人类癌细胞转移。

上皮间质转化（EMT）是转移中众所周知的重要步骤，因此可以成为癌症治疗中的关键靶标。在这里，我们测试了卷柏卷柏及其有效成分金黄色素（AF）的EMT抑制作用。使用伤口愈合和侵袭试验并通过监测EMT相关蛋白，E-钙粘蛋白，Snail和Twist的表达变化来体外检查EMT。使用注射了萤光素酶标记的A549细胞的SCID小鼠在体内检查转移情况。我们证实了水链球菌（STE）和AF的水提取物抑制了人类癌细胞系中的EMT。我们发现，无毒浓度的STE和AF对肿瘤坏死因子（TGF）-β处理的癌细胞的迁移（伤口愈合测定）和侵袭（Transwell测定）产生了显着的抑制作用。Western印迹和免疫荧光成像显示，与仅用TGF-β处理的细胞相比，AF处理还恢复了这些细胞中的E-钙粘着蛋白表达。通过监测注射尾静脉的循环A549-luc细胞向小鼠肺的迁移，研究了AF对转移的抑制作用。3周后，与仅用TGF-β治疗的小鼠相比，在用AF共同治疗的小鼠中观察到较少的结节。我们的发现表明，STE和AF是有前途的EMT抑制剂，最终是潜在的有效抗肿瘤药。与仅用TGF-β治疗的小鼠相比，在用AF治疗的小鼠中观察到的结节更少。我们的发现表明，STE和AF是有前途的EMT抑制剂，最终是潜在的有效抗肿瘤药。与仅用TGF-β治疗的小鼠相比，在用AF治疗的小鼠中观察到的结节更少。我们的发现表明，STE和AF是有前途的EMT抑制剂，最终是潜在的有效抗肿瘤药。