Theacrine attenuates epithelial mesenchymal transition in human breast cancer MDA‐MB‐231 cells

Theacrine, a purine alkaloid structurally similar to caffeine, has recently become of interest as a potential therapeutic compound. Here, we investigated the antimetastatic potential of theacrine on human breast cancer MDA‐MB‐231 cells. We observed that theacrine can reverse epithelial‐to‐mesenchymal transition (EMT), which resulted in a decrease in the levels of mesenchymal markers (Fibronectin, Vimentin, N‐cadherin, Twist, and Snail) and an increase in the levels of epithelial markers (Occludin and E‐cadherin) in the cells. Additionally, theacrine attenuates TGF‐β‐induced EMT, cell adhesion, migration, and invasion in MDA‐MB‐231 cells. Overall, our results suggest that theacrine may inhibit the breast cancer cell metastasis by reversing the EMT process.     

6-Methoxydihydrosanguinarine induces apoptosis and autophagy in breast cancer MCF-7 cells by accumulating ROS to suppress the PI3K/AKT/mTOR signaling pathway

6-Methoxydihydrosanguinarine (6-MDS) is a natural benzophenanthridine alkaloid extracted from Hylomecon japonica (Thunb.) Prantl. It is the first time to explore the effect and mechanism of 6-MDS in breast cancer. Network pharmacology, molecular docking, and molecular dynamics simulation technology were adopted to identify the potential targets and pathways of 6-MDS in breast cancer. Besides, cell proliferation, apoptosis, and western blotting assays were conducted to investigate the effect of 6-MDS on MCF-7 cells. Network pharmacology, molecular docking, and molecular dynamics simulation results confirmed the effect of 6-MDS on resisting breast cancer via the PI3K/AKT/mTOR signaling pathway. In addition, the functional experiments results demonstrated that 6-MDS inhibited proliferation and induced apoptosis and autophagy. The autophagy inhibitor chloroquine and the silence of Atg5 augmented the effect of 6-MDS on promoting apoptosis. Furthermore, 6-MDS suppressed the PI3K/AKT/mTOR signaling pathway, and the PI3K inhibitor LY294002 enhanced these changes and promoted the 6-MDS pro-apoptotic and autophagy effects. 6-MDS triggered the generation of reactive oxygen species. The pretreatment with antioxidant N-acetyl-L-cysteine reversed the changes induced by 6-MDS, including increases in apoptosis and autophagy and inhibition of the PI3K/AKT/mTOR pathway. In conclusion, 6-MDS induces the apoptosis and autophagy of MCF-7 cells by ROS accumulation to suppress the PI3K/AKT/mTOR signaling pathway.     

Quercetin reversed MDR in breast cancer cells through down‐regulating P‐gp expression and eliminating cancer stem cells mediated by YB‐1 nuclear translocation

Overexpression of P‐glycoprotein (P‐gp) plays an important role in mediating multidrug resistance (MDR), resulting in chemotherapy failure of tumor patients and enhancement of cancer stem cell characteristics. By preparing doxorubicin (Dox) resistant human breast cancer MCF‐7 cells, here, we wanted to evaluate the effects of quercetin (Que) on MDR reversal activity and investigate its possible mechanism. MCF‐7 and MCF‐7/dox cells were respectively treated by Dox, paclitaxel (Pac), or vincristine (Vcr) with or without Que intervention for 24 hr. Cell viability, cell apoptosis, cell cycle, intracellular drug accumulation, the expression of P‐gp and Y‐box binding protein 1 (YB‐1), and breast cancer stem cells (BCSCs) were then assessed. The results showed that Que significantly enhanced the antitumor activities of Dox, Pac, and Vcr in breast cancer cells. In addition, combined treatment of Dox, Pac, or Vcr with Que significantly downregulated P‐gp expression and eliminated BCSCs. Furthermore, combined treatment of Dox, Pac, or Vcr with Que significantly inhibited nuclear translocation of YB‐1. Thus, we speculated that Que reversed MDR in breast cancer cells through downregulating P‐gp expression and eliminating cancer stem cells mediated by YB‐1 nuclear translocation.     

冬凌草甲素诱导三阴乳腺癌MDA-MB-231细胞凋亡及对细胞内活性氧水平的影响

冬凌草甲素是从中药冬凌草Rabdosia rubescens中分离得到的一种贝壳杉烯二萜类的天然有机化合物,具有抗炎、抗菌、抗肿瘤等多种生物活性。该实验观察冬凌草甲素对三阴乳腺癌MDA-MB-231细胞凋亡的影响及其可能的作用机制。采用MTT法检测冬凌草甲素对MDA-MB-231细胞的增殖抑制作用,PI单染、Annexin V-FITC/PI双染流式细胞术分析冬凌草甲素对MDA-MB-231细胞凋亡的影响,活性氧(ROS)试剂盒检测细胞内ROS水平的变化,Western blot分析PARP,Bcl-2,caspase-3蛋白的表达情况。结果表明,冬凌草甲素对乳腺癌MDA-MB-231细胞具有明显的凋亡诱导作用,显著升高细胞内的ROS水平,下调抗凋亡蛋白Bcl-2的表达,并促进caspase-3及其底物PARP的切割。提示,冬凌草甲素诱导MDA-MB-231细胞凋亡的作用可能与升高细胞内ROS水平、下调Bcl-2的表达以及激活caspase-3相关。     

茯苓酸通过激活多聚腺苷二磷酸核糖聚合酶诱导人乳腺癌细胞MDA-MB-231凋亡

目的观察茯苓酸对人乳腺癌MDA-MB-231细胞增殖及凋亡的影响,并初步探讨作用机制。方法乳腺癌MDA-MB-231细胞与不同浓度(1、2、5μmol/L)的茯苓酸共孵育,采用CCK-8细胞增殖与活性检测试剂盒检测细胞存活率;流式细胞术Annexin V/PI双染色检测细胞凋亡;Western blotting法检测多聚腺苷二磷酸核糖聚合酶(PARP)及与细胞凋亡相关蛋白的表达。结果茯苓酸能够剂量和时间依赖性地抑制MDA-MB-231细胞的增殖,并可诱导MDA-MB-231细胞凋亡。浓度为1、2、5μmol/L的茯苓酸作用MDA-MB-231细胞48 h后,细胞凋亡率显著增加至25.6%、59.4%、87.2%,明显高于对照组凋亡率(5.4%);经过1、2、5μmol/L茯苓酸分别处理48 h后,实验组MDA-MB-231细胞中凋亡蛋白标志物PARP裂解量升高,且呈剂量依赖性。结论茯苓酸能抑制MDA-MB-231细胞的增殖并诱导其凋亡,其作用机制与激活PARP有关。     

Polyphenols from Artemisia annua L Inhibit Adhesion and EMT of Highly Metastatic Breast Cancer Cells MDA‐MB‐231

Recent evidence suggests that polyphenolic compounds from plants have anti‐invasion and anti‐metastasis capabilities. The Korean annual weed, Artemisia annua L., has been used as a folk medicine for treatment of various diseases. Here, we isolated and characterized polyphenols from Korean A. annua L (pKAL). We investigated anti‐metastatic effects of pKAL on the highly metastatic MDA‐MB‐231 breast cancer cells especially focusing on cancer cell adhesion to the endothelial cell and epithelial‐mesenchymal transition (EMT). Firstly, pKAL inhibited cell viability of MDA‐MB‐231 cells in a dose‐dependent manner, but not that of human umbilical vein endothelial cells (ECs). Polyphenols from Korean A. annua L inhibited the adhesion of MDA‐MB‐231 cells to ECs through reducing vascular cell adhesion molecule‐1 expression of MDA‐MB‐231 and ECs, but not intracellular adhesion molecule‐1 at the concentrations where pKAL did not influence the cell viability of either MDA‐MB‐231 cells nor EC. Further, pKAL inhibited tumor necrosis factor‐activated MDA‐MB‐231 breast cancer cell invasion through inhibition of matrix metalloproteinase‐2 and matrix metalloproteinase‐9 and EMT. Moreover, pKAL inhibited phosphorylation of Akt, but not that of protein kinase C. These results suggest that pKAL may serve as a therapeutic agent against cancer metastasis at least in part by inhibiting the cancer cell adhesion to ECs through suppression of vascular cell adhesion molecule‐1 and invasion through suppression of EMT. Copyright © 2016 John Wiley & Sons, Ltd.     

Activation of AMP‐activated protein kinase on human gastric cancer cells by apoptosis induced by corosolic acid isolated from Weigela subsessilis

Corosolic acid is one of the triterpenoids present in the leaves of Weigela subsessilis. The antidiabetic activity of corosolic acid has been reported previously, but to date, the anticancer effects on gastric cancer have been poorly studied. In this study, corosolic acid showed growth inhibition on SNU‐601 human gastric cancer cells, with an IC₅₀ value of 16.9 ± 2.9 μm . Corosolic acid also triggered the activation of caspase‐3 and poly (ADP‐ribose) polymerase, while it was recovered by Z‐VAD‐FMK. Moreover, the cell growth/apoptosis activities of corosolic acid were regulated by the AMP‐activated protein kinase‐mammalian target of rapamycin (AMPK‐mTOR) signals. These results showed that corosolic acid‐mediated AMPK activation leads to inhibition of mTOR, thus providing a possible mechanism of action of corosolic acid in the inhibition of cancer cell growth and the induction of apoptosis. Copyright © 2010 John Wiley & Sons, Ltd.     

SIRT1/AMPK and Akt/eNOS signaling pathways are involved in endothelial protection of total aralosides of Aralia elata (Miq) Seem against high‐fat diet‐induced atherosclerosis in ApoE−/− mice

Total aralosides of Aralia elata (Miq) Seem (TASAESs) possess multiple pharmacological activity, such as anti‐inflammation, antioxidation, and antiapoptosis. However, there is no literature reporting the antiatherosclerotic effect and mechanism of TASAES so far. The aim of this study was to investigate the antiatherosclerotic effects in high‐fat diet‐induced ApoE?/? mice and potential mechanism of TASAES in ox‐LDL‐injured endothelial cells. In vivo assay, our data demonstrated that TASAES significantly reduced the atherosclerotic plaque size and caspase‐3 expression level in aortic valve. In vitro, we found that TASAES could increase endothelial cell viability, attenuated mitochondrial membrane potential depolarization, and endothelial cells apoptosis. In addition, we found that TASAES could activate SIRT1/AMPK and Akt/eNOS signaling pathways. Importantly, EX527, SIRT1 siRNA, and LY294002, Akt siRNA, remarkably abolished the antiapoptotic effects of TASAES. In conclusion, this study demonstrated that SIRT1/AMPK and Akt/eNOS signaling pathways are involved in endothelial protection of TASAES against atherosclerotic mice, suggesting that TASAES is a candidate drug for atherosclerosis treatment.     

迷迭香酸通过AMPK/mTOR通路减轻新生大鼠缺血缺氧性脑损伤研究

目的 探讨迷迭香酸对新生大鼠缺血缺氧脑损伤（hypoxic-ischemic encephalopathy,HIE）的影响,及其对单磷酸腺苷活化蛋白激酶（adenosine monophosphate activated protein kinase,AMPK）/雷帕霉素靶蛋白（mammalian target of rapamycin,mTOR）通路的调控作用,初步探讨其脑保护机制。方法 取7 d龄SD新生大鼠,随机分为对照组、模型组、迷迭香酸（300 mg/kg）组、AMPK/mTOR激动剂MT6378（10 mg/kg）组、AMPK抑制剂GSK-690693（30 mg/kg）组和迷迭香酸（300 mg/kg）+MT6378（10 mg/kg）组,每组20只。建立HIE模型,给予相应药物进行干预,采用TTC染色法检测大鼠脑梗死情况;透射电镜（TEM）观察大鼠海马神经元结构损伤及自噬状况;免疫荧光法检测大鼠海马神经元自噬标记物微管相关蛋白1轻链3B（microtubule-associated protein 1 light chain 3B,LC3B）阳性表达;TUNEL法检测大鼠海马神经元凋亡率;免疫组化法检测大鼠海马神经元磷酸化AMPK（p-AMPK）阳性表达;Western blotting检测大鼠海马组织活化的半胱氨酸蛋白酶3（cleaved Caspase-3）、mTOR及其磷酸化蛋白（p-mTOR）、Unc-51样自噬激活激酶1（uncoordinated-51 like autophagy activating kinase 1,Ulk1）及其磷酸化蛋白（p-Ulk1）、LC3B表达。结果 与对照组相比,模型组大鼠脑梗死严重,海马神经元结构损伤及自噬空泡形成较多,细胞自噬及凋亡水平升高,AMPK/mTOR通路活化（P<0.05）。与模型组相比,迷迭香酸组及GSK-690693组大鼠脑梗死、海马神经元结构损伤、凋亡及自噬减弱,AMPK/mTOR通路被抑制（P<0.05）;MT6378组海马组织AMPK/mTOR通路进一步激活,大鼠脑梗死、海马神经元结构损伤、凋亡及自噬进一步加重（P<0.05）;MT6378可逆转迷迭香酸的上述作用（P<0.05）。结论 迷迭香酸可能通过抑制AMPK/mTOR通路激活,降低海马神经元自噬及凋亡进程,发挥抗HIE脑损伤作用。     

基于AMPK/SIRT1/SREBP1信号通路探究膜肾颗粒对膜性肾病大鼠蛋白尿的治疗作用

目的 基于单磷酸腺苷活化的蛋白激酶（adenosine monophosphate-activated protein kinase,AMPK）/沉默信息调节因子1(silent information regulator 1,SIRT1)/固醇调节元件结合蛋白1(sterol regulatory element-binding protein 1,SREBP1)信号通路观察膜肾颗粒对膜性肾病大鼠蛋白尿的影响及作用机制。方法 80只SD大鼠随机挑选15只为空白组,其余大鼠利用改良Border法建立膜性肾病大鼠模型,造模大鼠随机分为模型组、环孢素A(cyclosporin A,CsA)组和膜肾颗粒低、高剂量（1.85、7.38 g/kg）组。观察大鼠一般状态,采用双缩脲比色法检测大鼠造模前、造模后、给药结束后24 h尿蛋白定量（urinary protein quantity,UTP）;使用全自动生化仪检测大鼠尿素氮（blood urea nitrogen,BUN）、血肌酐（serum creatinine,Scr）、总胆固醇（total cholesterol,TC）、三酰甘油（tr...     

Atractylenolide-1 affects glycolysis/gluconeogenesis by downregulating the expression of TPI1 and GPI to inhibit the proliferation and invasion of human triple-negative breast cancer cells

Atractylenolide-1 (AT-1) is a major octanol alkaloid isolated from Atractylodes Rhizoma and is widely used to treat various diseases. However, few reports have addressed the anticancer potential of AT-1, and the underlying molecular mechanisms of its anticancer effects are unclear. This study aimed to assess the effect of AT-1 on triple-negative breast cancer (TNBC) cell proliferation and migration and explore its potential molecular mechanisms. Cell invasion assays confirmed that the number of migrating cells decreased after AT-1 treatment. Colony formation assays showed that AT-1 treatment impaired the ability of MDA-MB-231 cells to form colonies. AT-1 inhibited the expression of p-p38, p-ERK, and p-AKT in MDA-MB-231 cells, significantly downregulated the proliferation of anti-apoptosis-related proteins CDK1, CCND1, and Bcl2, and up-regulated pro-apoptotic proteins Bak, caspase 3, and caspase 9. The gas chromatography–mass spectroscopy results showed that AT-1 downregulated the metabolism-related genes TPI1 and GPI through the glycolysis/gluconeogenesis pathway and inhibited tumor growth in vivo. AT-1 affected glycolysis/gluconeogenesis by downregulating the expression of TPI1 and GPI, inhibiting the proliferation, migration, and invasion of (TNBC) MDA-MB-231 cells and suppressing tumor growth in vivo.     

基于AMPK/mTOR信号通路研究异常山碱对EC9706细胞能量代谢的调控机制

目的通过观察异常山碱对食管癌EC9706细胞的增殖、凋亡、周期、能量代谢及能量代谢通路相关蛋白表达的影响,探讨其治疗食管癌的分子机制。方法常规培养ECC9706细胞,用MTT法检测细胞活性,筛选药物浓度,选择1、2μg/mL 2个质量浓度;流式细胞术检测异常山碱对EC9706细胞凋亡、周期的影响,能量代谢检测系统检测异常山碱对EC9706细胞能量代谢的影响,Westernblotting检测细胞中哺乳动物雷帕霉素靶蛋白(mTOR)、磷酸化哺乳动物雷帕霉素靶蛋白(p-mTOR)、磷酸化乙酰辅酶A羧化酶(p-ACC)、腺苷磷酸激活蛋白激酶(AMPK)蛋白表达。结果不同质量浓度异常山碱作用48h后能有效抑制EC9706细胞增殖,呈剂量依赖性(P0.01),可以将EC9706细胞阻滞于S期和G_2/M期(P0.05),有效促进细胞凋亡(P0.05),且明显抑制细胞糖酵解及线粒体代谢能力(P0.01),与对照组比较,异常山碱组细胞AMPK蛋白表达水平上升,mTOR、p-mTOR、p-ACC蛋白表达水平降低(P0.05)。结论异常山碱可能通过能量代谢调节EC9706细胞周期、凋亡,抑制EC9706细胞增殖。     

蓝萼甲素对三阴性乳腺癌MDA-MB-231细胞增殖及细胞周期的影响

目的研究蓝萼甲素对三阴性乳腺癌MDA-MB-231细胞增殖及细胞周期的影响及其作用机制。方法采用MTT法检测蓝萼甲素对MDA-MB-231细胞增殖的影响;流式细胞仪检测细胞周期;Western blotting法检测细胞中cyclin B1、cyclin D1、细胞周期素依赖激酶2(CDK2)、CDK4、p53、p21、p27、组蛋白赖氨酸特异性去甲基化酶1(LSD1)、组蛋白H3第4位赖氨酸二甲基化(H3K4me2)、组蛋白H3第9位赖氨酸二甲基化(H3K9me2)蛋白表达水平。结果蓝萼甲素能显著抑制MDA-MB-231细胞的增殖,呈剂量和时间依赖性;提高G2/M期细胞比例;上调p53、p21、p27、H3K4me2、H3K9me2蛋白表达水平,下调cyclin B1、cyclin D1、CDK2、CDK4、LSD1蛋白表达水平。结论蓝萼甲素抑制MDA-MB-231细胞增殖,阻滞MDA-MB-231细胞周期于G2/M期,其机制可能与激活p53的表达及调控组蛋白的甲基化作用有关。     

萝卜硫素通过Traf6/TAK1信号通路介导人胃癌细胞凋亡的机制研究

[目的]探讨萝卜硫素对人胃癌(HGC27)细胞增殖、凋亡的影响,并观察其可能作用的机制。[方法]将对数生长期的HGC27细胞分为空白对照组、15μg/m L萝卜硫素、30μg/m L萝卜硫素及60μg/m L萝卜硫素,用不同浓度药物处理细胞后,采用CCK8法检测各组细胞的增殖情况,流式细胞术检测各组细胞的凋亡率,免疫印迹技术检测细胞中凋亡蛋白及肿瘤坏死因子受体相关分子6(Traf6)/转化生长因子-β活化激酶1(TAK1)信号通路蛋白表达量。[结果]与空白对照组相比,不同浓度萝卜硫素组细胞增殖抑制率及凋亡率明显升高(P0.05);促凋亡蛋白半胱氨酸天冬氨酸蛋白酶-3(Caspase-3)、Bcl-2相关X蛋白(Bax)表达水平显著升高,而抗凋亡蛋白B淋巴细胞瘤-2(Bcl-2)水平则显著降低(P0.05);Traf6、p-TAK1蛋白表达量相对于空白对照组显著升高(P0.05)。[结论]萝卜硫素可以抑制人胃癌细胞的增殖,促进细胞的凋亡,Traf6/TAK1信号通路可能参与了萝卜硫素对肿瘤细胞的抑制作用。     

Cytotoxicity of Tanshinone IIA combined with Taxol on drug‐resist breast cancer cells MCF‐7 through inhibition of Tau

Drug resistance represents a major obstacle to improving the overall response and survival of cancer patients. Taxol is one of the most commonly used chemotherapy agents in breast cancer. As with many cancer therapeutic agents, resistance remains a significant problem when using Taxol to treat malignancies. In this study, estrogen receptor positive breast cancer cells MCF‐7 were induced Taxol resistance. And Tanshinone IIA combined with Taxol was chosen to treat it. The drugs combination showed additive effect in most drug concentrations. Drug resistance cancer cells showed a higher microtubule associated protein (Tau) expression, which was considered as one of the reasons for Taxol resistance. Tanshinone IIA inhibited the expression of Tau in MCF‐7 cells and resulted in higher sensibility of Taxol. Moreover, Tanshinone IIA also showed cytotoxicity to MCF‐7, which might be related to its estrogenicity effect. In conclusion, the combination of Tanshinone IIA and Taxol showed higher cytotoxicity to Taxol resistant MCF‐7 cells, which might be related to the inhibition of Tau.     

Anticancer activity and molecular mechanisms of α‐conidendrin,a polyphenolic compound present in Taxus yunnanensis,on human breast cancer cell lines

α‐Conidendrin is a polyphenolic compound found mainly in Taxus yunnanensis, as the source of chemotherapy drug paclitaxel, which has been used in traditional medicine for treatment of cancer. This study aimed to investigate the anticancer activity and molecular mechanisms of α‐conidendrin on breast cancer cell lines. The results of the present study show that α‐conidendrin possesses potent antiproliferative effects on breast cancer cell lines MCF‐7 and MDA‐MB‐231. α‐Conidendrin significantly induced apoptosis in breast cancer cells via reactive oxygen species generation, upregulation of p53 and Bax, downregulation of Bcl‐2, depolarization of mitochondrial membrane potential (MMP), release of cytochrome c from mitochondria, and activation of caspases‐3 and ‐9. α‐Conidendrin remarkably inhibited the proliferation of breast cancer cells through induction of cell cycle arrest by upregulating p53 and p21 and downregulating cyclin D1 and CDK4. Unlike breast cancer cells, the antiproliferative effect of α‐conidendrin on human foreskin fibroblast cells (normal cells) was very small. In normal cells, reactive oxygen species levels, loss of MMP, release of cytochrome c, mRNA expression of p53, p21, cyclin D1, CDK4, Bax, and Bcl‐2 as well as mRNA expression and activity of caspases‐3 and ‐9 were significantly less affected by α‐conidendrin compared with cancer cells. These results suggest that α‐conidendrin can be a promising agent for treatment of breast cancer with little or no toxicity against normal cells.