Sweet potato is a functional food with potential antitumor properties, but the bioactive constituents and biological mechanisms remain unclear. In this study, we investigated the antitumor effect of daucosterol linolenate extracted from sweet potato and its potential mechanism. An MTT assay indicated that DLA inhibited the proliferation of breast cancer MCF-7 cells but had only weak effects on the proliferation of MDA-MB-231, 4T1, and MCF-10A cells. Flow cytometry analysis revealed that daucosterol linolenate induced apoptosis of MCF-7 cells. Experiments with MCF-7 xenograft in nude mice further confirmed that DLA inhibited tumor growth dose-dependently. After DLA treatment, the expressions of B-cell lymphoma 2 and vascular endothelial growth factor were decreased and that of cleaved caspase 3 was increased as compared to the TC group. DLA also down-regulated the expression of phosphoinositide 3-kinase/protein kinase B and repressed insulin-induced phosphoinositide 3-kinase/protein kinase B activation. Our findings suggest that DLA suppresses breast tumor growth through inactivating the phosphoinositide 3-kinase/protein kinase B pathway.

中文翻译：

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甘薯中的亚麻酸豆蔻甾醇通过调节 PI3K/AKT 通路抑制 MCF7-异种移植物-肿瘤生长

甘薯是一种具有潜在抗肿瘤特性的功能性食品，但其生物活性成分和生物学机制尚不清楚。在本研究中，我们研究了从甘薯中提取的亚麻酸豆蔻甾醇的抗肿瘤作用及其潜在机制。MTT试验表明，DLA抑制乳腺癌MCF-7细胞的增殖，但对MDA-MB-231、4T1和MCF-10A细胞的增殖作用微弱。流式细胞术分析显示，亚麻酸豆蔻甾醇诱导MCF-7细胞凋亡。在裸鼠中用 MCF-7 异种移植物进行的实验进一步证实，DLA 剂量依赖性地抑制肿瘤生长。与TC组相比，DLA治疗后B细胞淋巴瘤2和血管内皮生长因子的表达降低，cleaved caspase 3的表达增加。DLA 还下调磷酸肌醇 3-激酶/蛋白激酶 B 的表达并抑制胰岛素诱导的磷酸肌醇 3-激酶/蛋白激酶 B 激活。我们的研究结果表明，DLA 通过使磷酸肌醇 3-激酶/蛋白激酶 B 途径失活来抑制乳腺肿瘤的生长。