Fatostatin in Combination with Tamoxifen Induces Synergistic Inhibition in ER-Positive Breast Cancer
Fatostatin in Combination with Tamoxifen Induces Synergistic Inhibition in ER-Positive Breast Cancer
复制标题
Fatostatin 与他莫昔芬联合对 ER 阳性乳腺癌产生协同抑制作用
DOI：
10.2147/dddt.s253876
复制
发表时间：
2020-01-01
影响因子：
4.8
通讯作者：
Yang, Qifeng
中科院分区：
文献类型：
--
作者：
Liu, Ying;Zhang, Ning;Yang, Qifeng
背景：他莫昔芬是激素受体阳性乳腺癌辅助治疗的基石。尽管有效，但有限的药物敏感性和内分泌耐药仍然是临床上的重要挑战。这项研究的主要目的是研究在体内外都能使乳腺癌对他莫昔芬的抗肿瘤作用增敏的法托他汀。方法采用免疫沉淀法检测Fatostatin诱导的ER降解。采用四甲基偶氮唑盐比色法和集落形成法检测两种药物对MCF-7和T47D细胞的抗肿瘤作用。流式细胞仪检测细胞周期停滞。用膜联蛋白V/碘化丙啶双重染色和原位末端标记法检测细胞凋亡。MDC法和丫啶橙染色检测细胞自噬。使用Transwell系统进行迁移和侵袭分析，并使用BALB/c nu/nu雌性小鼠的MCF-7异种移植模型评估体内协同使用Fate ostatin和Tamoxifen的效果。结果通过PI3K-AKT-mTOR信号通路，Fate-statin和Tamoxifen联合应用显著抑制MCF-7和T47D细胞的活力和侵袭力，诱导细胞周期停滞，并调节细胞的凋亡和自噬。此外，经他莫昔芬和他莫昔芬治疗后，ATG7/12/13、BECLIN和LC3B的表达水平升高，而p-mTOR和p62的表达水平降低。在异种移植模型中，FATOSTATIN和他莫昔芬的协同治疗显著抑制了肿瘤的生长。结论脂肪抑制素可通过K48连接的泛素化诱导ER降解，这是他莫昔芬抑制乳腺癌PI3K-AKT-mTOR信号通路的关键机制。脂肪抑制素对ER阳性的乳腺癌患者可能有很好的临床应用前景。
Background Tamoxifen is the cornerstone of adjuvant therapy for hormone receptor-positive breast cancer. Despite its efficacy, limited drug sensitivity and endocrine resistance remain the important clinical challenges. The main objective of this study was to investigate fatostatin, which was found to sensitize breast cancer to the antitumour effect of tamoxifen both in vitro and in vivo. Methods Fatostatin-induced ER degradation was detected by immunoprecipitation assay. The antitumour effect of fatostatin and tamoxifen on MCF-7 and T47D cells was assessed by MTT and colony forming assays. Cell cycle arrest was detected by flow cytometric analysis. Apoptosis was detected by annexin V/propidium iodide double staining and TUNEL assay. Autophagy was detected by MDC assay and acridine orange staining. Migration and invasion assays were performed using a Transwell system, and the efficacy of the synergistic use of fatostatin and tamoxifen in vivo was evaluated using an MCF-7 xenograft model in BALB/c nu/nu female mice. Results The synergistic use of fatostatin and tamoxifen significantly suppressed cell viability and invasion, induced cell cycle arrest, and regulated apoptosis and autophagy in MCF-7 and T47D cell lines via PI3K-AKT-mTOR signalling. Additionally, the expression levels of Atg7/12/13, beclin and LC3B increased while p-mTOR and P62 expression levels decreased after treatment with fatostatin and tamoxifen. Tumor growth in the xenograft model was suppressed significantly with the synergistic treatment of fatostatin and tamoxifen. Conclusion Fatostatin could induce ER degradation by K48-linked polyubiquitination, which was the key mechanism contributing to tamoxifen inhibition of PI3K-AKT-mTOR signalling in breast cancer. Fatostatin may have a promising clinical use for ER-positive breast cancer patients.