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1.
Elevated phosphoethanolamine (PE) is frequently observed in MRS studies of human cancers and xenografts. The role of PE in cell survival and the molecular causes underlying this increase are, however, relatively underexplored. In this study, we investigated the roles of ethanolamine kinases (Etnk‐1 and 2) and choline kinases (Chk‐α and β) in contributing to increased PE in human breast and pancreatic cancer cells. We investigated the effect of silencing Etnk‐1 and Etnk‐2 on cell viability as a potential therapeutic strategy. Both breast and pancreatic cancer cells showed higher PE compared with their nonmalignant counterparts. We identified Etnk‐1 as a major cause of the elevated PE levels in these cancer cells, with little or no contribution from Chk‐α, Chk‐β, or Etnk‐2. The increase of PE observed in pancreatic cancer cells in culture was replicated in the corresponding tumor xenografts. Downregulation of Etnk‐1 with siRNA resulted in cell cytotoxicity that correlated with PE levels in breast and pancreatic cancer cells. Etnk‐1 may provide a potential therapeutic target in breast and pancreatic cancers.  相似文献   

2.
Oestrogen receptor (ERalpha) expression is a strong predictor of response to endocrine therapy. The PI3K/AKT/mTOR signal transduction pathway has been implicated in endocrine resistance in vitro. The present study was carried out to test the hypothesis that AKT activation mediates tamoxifen resistance in clinical breast cancer. Immunohistochemistry (IHC) using AKT1-3, pan-AKT, pAKT (Thr-308), pAKT (Ser-473), pER (Ser-167), and pHER2 antibodies was performed on 402 ERalpha-positive breast carcinomas from patients treated with tamoxifen. High pAKT (Ser-473) activity (p = 0.0406) and low AKT2 expression (p = 0.0115) alone, or in combination [high pAKT (Ser-473)/low AKT2; 'high-risk' patient group] (p = 0.0014), predicted decreased overall survival in tamoxifen-treated patients with ERalpha-positive breast cancers. There was no significant association between tumour levels of AKT expression or activity and disease-free survival (DFS); however, the 'high-risk' patient group was significantly more likely to relapse (p = 0.0491). During tamoxifen treatment, neither AKT2 nor pAKT predicted DFS. Finally, activation of AKT, via phosphorylation, was linked to activation of both HER2 and ERalpha in this patient cohort. The data presented here show that the PI3K/AKT/mTOR pathway is associated with relapse and death in ERalpha-positive breast cancer patients treated with tamoxifen, supporting in vitro evidence that AKT mediates tamoxifen resistance. Patients with a 'high-risk' expression profile were at increased risk of death (hazard ratio 3.22, p = 0.002) relative to 'low-risk' patients, highlighting the potential that tumour profiling, with multiple IHC markers predictive of therapeutic response, may improve patient selection for endocrine therapies, eg tamoxifen or aromatase inhibitor-based treatments.  相似文献   

3.
目的:观察穿心莲内酯对卵巢癌细胞株SKOV-3侵袭与凋亡的影响并探讨初步的作用机制。方法:CCK-8法检测不同浓度(0、5、10、20和40μmol/L)的穿心莲内酯对SKOV-3细胞作用不同时间(12、24、36和48h)后,SKOV-3细胞存活率的变化;Transwell法与TUNEL法分别检测SKOV-3细胞侵袭能力与凋亡能力的变化;Western blot法检测p-PI3K、p-Akt与p-mTOR蛋白水平的变化。结果:CCK-8法检测结果显示,随着浓度增加与培养时间延长,穿心莲内酯对SKOV-3细胞存活率的抑制程度增强;采用20μmol/L穿心莲内酯培养SKOV-3细胞36h后,SKOV-3细胞的侵袭数明显降低,凋亡数明显增加(P0.05),p-PI3K、p-Akt与p-mTOR的蛋白水平明显降低(P0.05)。结论:穿心莲内酯能够抑制卵巢癌细胞SKOV-3的活力与侵袭能力,增强凋亡能力,这可能与抑制PI3K/Akt/mTOR信号通路有关。  相似文献   

4.
桔皮素对人非小细胞肺癌细胞生长及侵袭的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:探讨桔皮素(TGN)对非小细胞肺癌(NSCLC)细胞生长和侵袭的影响及其分子机制。方法:体外培养非小细胞肺癌A549细胞,分别用不同浓度的TGN处理,MTT比色法检测细胞活性,Annexin V-FITC/PI染色及流式细胞术检测细胞凋亡率,Transwell检测细胞侵袭,RT-PCR分析MMP-2和MMP-9的mRNA表达水平,Western blotting检测Ki67、Cyt C、caspase-3、cleaved caspase-3、MMP-2、MMP-9、Akt、p-Akt以及p-PI3K表达水平。结果:桔皮素剂量依赖性地抑制A549细胞增殖(P0.05),同时伴随有增殖标记分子Ki67表达水平的下调。分析发现,桔皮素诱导细胞中Cyt C、caspase-3和cleaved caspase-3的表达上调(P0.01),加速A549细胞的凋亡。此外,桔皮素作用后,A549细胞中侵袭相关蛋白MMP-2和MMP-9的表达量下降,且侵袭数目随桔皮素浓度增加而减少。进一步研究表明,桔皮素作用后A549细胞中p-Akt和p-PI3K表达水平降低(P0.05),阻断PI3K/Akt信号通路后,不同浓度TGN对细胞活性影响没有变化。结论:桔皮素能抑制A549细胞生长及侵袭,促进细胞凋亡,可能通过抑制PI3K/Akt信号通路的激活起作用。因此,本研究将为非小细胞肺癌的防治提供新的研究方向。  相似文献   

5.
目的:研究受体相互作用蛋白2(Rip2)是否诱导人胰腺癌细胞株Panc-1发生自噬及其作用机制。方法:用jet PRIME转染试剂将空质粒pEGFP-C2和重组质粒pEGFP-Rip2分别转染入Panc-1细胞,不做处理的细胞为对照组。转染后培养细胞48 h,采用Western blot检测Rip2、自噬相关蛋白[beclin-1和微管相关蛋白1轻链3Ⅱ(LC3-Ⅱ)]及磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(Akt)/哺乳动物雷帕霉素靶蛋白(mTOR)通路相关蛋白的表达;透射电子显微镜观察自噬体的数量。结果:转染pEGFP-Rip2的细胞Rip2蛋白表达显著增加。与对照组和pEGFP-C2组相比,pEGFP-Rip2组细胞的beclin-1和LC3-Ⅱ蛋白表达水平显著升高(均P0.01);在透射电子显微镜下观察发现,pEGFP-Rip2组细胞内自噬体的数量明显多于对照组和pEGFP-C2组。pEGFP-Rip2组细胞的p-Akt和p-mTOR蛋白水平明显低于对照组和pEGFP-C2组(均P0.01),而总Akt和mTOR的蛋白水平变化不明显。结论:过表达Rip2可诱导Panc-1细胞发生自噬,其作用机制可能与Rip2抑制PI3K/Akt/mTOR通路的活化有关。  相似文献   

6.
目的:观察胡椒碱对卵巢癌细胞株SKOV-3的侵袭与凋亡的影响并讨论其作用机制.方法:CCK-8法检测不同浓度的胡椒碱(0,5,10和20μmol/L)对SKOV-3细胞作用不同时间(12,24和36 h)后,SKOV-3细胞存活率的变化;Transwell小室法与TUNEL法分别检测SKOV-3细胞侵袭能力与凋亡能力的变化;Western印迹检测p-PI3K与p-Akt蛋白表达水平的变化.结果:CCK-8法结果显示胡椒碱随浓度增加与培养时间增长,对SKOV-3细胞存活率的抑制程度增强;采用10μmol/L胡椒碱培养SKOV-3细胞36 h后,SKOV-3细胞的细胞侵袭数明显降低,细胞凋亡数明显增加,差异有统计学意义(P<0.05);p-PI3K与p-Akt蛋白表达水平明显降低,差异有统计学意义(P<0.05).结论:胡椒碱能够抑制卵巢癌细胞SKOV-3的增殖与侵袭能力,其增加凋亡能力可能与抑制PI3K/Akt信号通路有关.  相似文献   

7.
8.
目的:探讨毒蕈碱胆碱受体3(muscarinic receptor 3,M3R)激动剂卡巴胆碱促进人肺癌A549细胞上皮间质转化的可能信号通路。方法:用400μmol/L卡巴胆碱刺激人肺癌A549细胞,在倒置相差显微镜下观察细胞形态的变化,应用划痕愈合实验和Transwell实验观察细胞迁移和侵袭能力;应用q PCR技术检测上皮间质转化相关蛋白波形蛋白(vimentin)和E钙黏蛋白(E-cadherin)m RNA水平的变化;应用Western blot技术检测p-AKT、vimentin和E-cadherin蛋白水平的变化。结果:卡巴胆碱刺激人肺癌A549细胞后,细胞形态发生明显改变,由不规则多边形逐渐向梭形转化、细胞间紧密结合逐渐变得松散,细胞迁移和侵袭能力增强;vimentin的m RNA和蛋白表达量明显增加,E-cadherin的m RNA和蛋白水平降低,磷酸化的AKT蛋白水平增加,且这些变化均可被M3R特异性抑制剂4-DAMP所抑制(P0.05)。结论:卡巴胆碱可通过激活PI3K/AKT信号途径促进人肺癌A549细胞发生上皮间质转化。  相似文献   

9.
Breast cancer which has a high incidence rate is the 2nd lethal diseases only followed by lung cancer in women. How to improve the recovery rate is the principal problem should be solved in clinical. Previous studies demonstrated the importance of DJ-1 in the existence of breast cancer for the secreted of protein into serum by breast cancer cells both in vitro and in vivo. So the DJ-1 probably could be selected as the target in breast cancer treatment. Adriamycin resistance breast cancer cells MCF-7 and DJ-1 siRNA plasmid were employed to explore the potential clinical application of DJ-1 in this study. Our results showed that the sensitivity of cancer cells to chemotherapeutics was significantly improved with the transfection of DJ-1 siRNA. Further mechanism studies indicated the role of PI3K/AKT/MTOR pathway in the improvement of apoptosis after treatment with adriamycin in DJ-1 silence group.  相似文献   

10.
目的:探讨槲皮苷是否通过抑制PI3K/AKT信号通路诱导人胃癌SGC7901细胞凋亡。方法:选取SGC7901细胞作为研究对象,采用MTT法检测槲皮苷对SGC7901细胞的毒性作用并测定IC50值。实验分为对照组(不加药处理)、槲皮苷组(采用200μmol/L槲皮苷处理)、PI3K/AKT通路激动剂胰岛素样生长因子1(IGF-1)组(采用100μg/L IGF-1处理)和槲皮苷+IGF-1组(采用200μmol/L槲皮苷+100μg/L IGF-1共处理)。处理48 h后,采用流式细胞术检测细胞凋亡,Western blot法检测cleaved caspase-3、p-AKT(Ser473)、AKT、p-PI3K(Tyr508)和PI3K的蛋白水平。结果:从100μmol/L开始,随着槲皮苷处理浓度的逐渐升高,SGC7901细胞活力显著降低(P 0. 05),槲皮苷作用48 h的IC50值为275. 40μmol/L。200μmol/L槲皮苷作用SGC7901细胞48 h后,与对照组比较,细胞凋亡率和cleaved caspase-3蛋白水平显著上升(P 0. 05),p-AKT和p-PI3K蛋白水平显著降低(P 0. 05),然而IGF-1与槲皮苷共同作用时,IGF-1可逆转槲皮苷对SGC7901细胞的作用效果。结论:槲皮苷能够诱导胃癌SGC7901细胞凋亡,其作用机制可能与抑制PI3K/AKT信号通路的激活有关。  相似文献   

11.
乳腺癌是女性最常见的肿瘤,大约75%的乳腺癌表达雌激素受体和/或孕激素受体.激素受体阳性的转移性乳腺癌患者通常采用内分泌治疗,然而由于内分泌治疗耐药的产生,其应用受到了限制.近年来发现,PI3K/Akt(丝氨酸/苏氨酸激酶)信号通路在乳腺癌的发展中发挥着重要作用.本文对PI3K/Akt信号通路在乳腺癌内分泌治疗耐药中的作用进行了综述,以期为雌激素受体阳性乳腺癌治疗提供新对策.  相似文献   

12.
This study investigated the association between the total choline (tCho) concentration and the clinical characteristics and biomarker status of breast cancer. Sixty‐two patients with breast cancer, 1.5 cm or larger in size on MR images, were studied. The tCho concentration was correlated with the MRI features, contrast enhancement kinetics, clinical variables and biomarkers. Pairwise two‐tailed Spearman's nonparametric test was used for statistical analysis. The tCho concentration was higher in high‐grade than moderate‐/low‐grade tumors (p = 0.04) and in tumors with higher Ktrans and kep (p < 0.001 for both). The association of tCho concentration with age (p = 0.05) and triple negative biomarker (p = 0.09) approached significance. tCho was not detected in 17 patients, including 15 with invasive ductal cancer and two with infiltrating lobular cancer. Fifteen of the 17 patients had moderate‐ to low‐grade cancers, and 11 had human epidermal growth factor‐2‐negative cancer, suggesting that these two factors might lead to false‐negative choline. Higher tCho concentration in high‐grade tumors and tumors with higher Ktrans and kep indicates that choline is associated with cell proliferation and tumor angiogenesis. The higher choline level in younger women may be caused by their more aggressive tumor type. The results presented here may aid in the better interpretation of 1H MRS for the diagnosis of breast lesions. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

13.
目的:探讨DDX3表达上调在人宫颈癌细胞增殖中的作用。方法:采用免疫组织化学方法检测2012年4月至2013年3月河南省人民医院59例宫颈癌组织及癌旁非肿瘤组织标本中的DDX3表达情况。同时,以宫颈癌细胞HeLa为研究对象,通过慢病毒介导的宫颈癌细胞过度表达来检测DDX3的功能。采用细胞增殖与活性检测试剂盒评估细胞存活...  相似文献   

14.
子宫内膜癌(EC)是最常见的女性生殖道恶性肿瘤之一,其发生发展的分子生物学机制十分复杂。近年来研究发现,磷脂酰肌醇-3激酶/蛋白激酶B/哺乳动物雷帕霉素靶蛋白(PI3K/Akt/mTOR)信号通路调节异常与子宫内膜癌密切相关。PI3K/Akt/mTOR信号通路中的多种受体及激酶的突变和异常激活,可能成为子宫内膜癌治疗的靶点。  相似文献   

15.
Epidermal growth factor (EGF) may increase cell motility,an event implicated in cancer cell invasion and metastasis.However,the underlying mechanisms for EGF-induced cell motility remain elusive.In this study,we found that EGF treatment could activate Ras-related C3 botulinum toxin substrate 1 (Rac1),PI3K/Akt and p21actived kinase (PAK1) along with cell migration.Ectopic expression of PAK1 K299R,a dominant negative PAK1 mutant,could largely abolish EGF-induced cell migration.Blocking PI3K/Akt signalling with LY294002 or Akt siRNA remarkably inhibited both EGF-induced PAK1 activation and cell migration.Furthermore,expression of dominant-negative Rac1 (T17N) could largely block EGF-induced PI3K/Akt-PAK1 activation and cell migration.Interestingly,EGF could induce a significant production of ROS,and N-acetyl-L-cysteine,a scavenger of ROS which abolished the EGF-induced ROS generation,cell migration,as well as activation of PI3K/Akt and PAK,but not Rac1.Our study demonstrated that EGF-induced cell migration involves a cascade of signalling events,including activation of Rac1,generation of ROS and subsequent activation of PI3K/Akt and PAK1.  相似文献   

16.
Objective: To determine the effect and mechanism of the long non-coding RNA (lncRNA) ncRuPAR (non-protein coding RNA, upstream of coagulation factor II thrombin receptor [F2R]/protease-activated receptor-1 [PAR-1]) in human gastric cancer.Methods: HGC-27-ncRuPAR overexpression and MGC-803-ncRuPAR-RNAi knockdown gastric cancer cell lines were established. We assessed the effect of ncRuPAR on cell proliferation, apoptosis, migration, and invasion using Cell Counting Kit 8, flow cytometry, scratch and transwell assays, respectively. Differentially expressed genes in HGC-27-ncRuPAR overexpression and HGC-27-empty vector cell lines were identified using Affymetrix GeneChip microarray analysis. Ingenuity Pathway Analysis (IPA) of the microarray results was subsequently conducted to identify ncRuPAR-enriched pathways, followed by validation using real time-quantitative PCR (RT-qPCR). As one of the top enriched pathways, phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway was further examined by western blotting to determine its role in ncRuPAR-mediated regulation of gastric cancer pathogenesis.Results: ncRuPAR inhibited human gastric cancer cell proliferation and induced G1/S phase arrest and apoptosis, but did not affect migration or invasion in vitro. Overexpression of ncRuPAR in vitro was found to inhibit its known target PAR-1, as well as PI3K/Akt signaling. The downstream targets of PI3K/Akt, cyclin D1 was downregulated, but there was no change in expression level of B-cell lymphoma 2 (Bcl-2).Conclusions: We showed that lncRNA-ncRuPAR could inhibit tumor cell proliferation and promote apoptosis of human gastric cancer cells, potentially by inhibiting PAR-1, PI3K/Akt signaling, and cyclin D1. The results suggest a potential role for lncRNAs as key regulatory hubs in GC progression.  相似文献   

17.
惠双 《中国病理生理杂志》2015,31(12):2126-2129
 目的: 探讨黄岑苷对宫颈癌细胞株HeLa的放射增敏作用及机制。方法: MTT法检测不同浓度黄岑苷对HeLa细胞的活力抑制能力,并计算IC50筛选实验药物浓度;克隆形成实验检测放射组与联合组在不同照射剂量下细胞的放射增敏作用;流式细胞术检测单药组、放射组与联合组的细胞周期变化;Western blot检测不同组细胞中Akt、p-Akt、Bad和p-Bad的蛋白水平。结果: 黄岑苷呈浓度依赖性抑制HeLa细胞的活力,IC50为43.65 mg/L,采用20% IC50浓度8 mg/L进行放射增敏实验。克隆形成实验结果显示8 mg/L黄岑苷联合放射治疗可使生存曲线左移,D0、Dq值显著小于放射组(P<0.05)。流式细胞仪检测结果显示黄岑苷阻滞HeLa细胞于G2/M期。联合组细胞中p-Akt和p-Bad的蛋白水平均显著高于其它各组(P<0.05)。结论: 黄岑苷对HeLa细胞具有放射增敏作用,其机制可能与其阻滞细胞于G2/M期和活化PI3K/Akt信号通路有关。  相似文献   

18.
目的 探讨南蛇藤醇抑制宫颈癌细胞增殖和侵袭的作用机制。 方法 将正常培养HeLa细胞分为对照组、南蛇藤醇低、中、高剂量组(终浓度分别为4 μmol/L、8 μmol/L和12 μmol/L)、阳性对照组(顺铂,终浓度为10 μmol/L)、LY294002组(LY294002,终浓度为20 μmol/L)和(南蛇藤醇+LY294002)组(南蛇藤醇和LY294002,终浓度分别为12 μmol/L和20 μmol/L)。MTT法检测各组细胞存活情况;流式细胞仪检测细胞凋亡情况;Transwell检测细胞的侵袭;蛋白质印迹法检测PI3K/AKT/NF-κB信号通路的表达;采用皮下注射HeLa细胞建立裸鼠模型,观察南蛇藤醇(120 mg/kg)对裸鼠移植瘤体积和重量的影响。 结果 与对照组相比,南蛇藤醇组、阳性对照组和LY294002组HeLa细胞的相对增殖率、侵袭细胞数均明显下降(P<0.001),细胞凋亡率明显升高(P<0.001),p-PI3K、p-AKT、NF-κB p65蛋白表达明显下调(P<0.001),且随着南蛇藤醇浓度升高,其作用增强;与LY294002组相比,(南蛇藤醇+LY294002)组HeLa细胞的相对增殖率和侵袭细胞数明显下降(q=10.182,q=10.217,P均<0.001),细胞凋亡率明显升高(q=23.636,P<0.001);与对照组相比,南蛇藤醇组裸鼠体重、移植瘤的体积和重量明显下降(q=4.100,P<0.020;q=13.501,P<0.001;q=5.078,P=0.005)。 结论 南蛇藤醇可能通过抑制HeLa细胞的PI3K/Akt/NF-κB信号通路,抑制其恶性生物学行为。  相似文献   

19.
This study demonstrates the feasibility of the noninvasive determination of important biomarkers of human (breast) tumor metabolism using high‐field (7‐T) MRI and MRS. 31P MRSI at this field strength was used to provide a direct method for the in vivo detection and quantification of endogenous biomarkers. These encompass phospholipid metabolism, phosphate energy metabolism and intracellular pH. A double‐tuned, dual‐element transceiver was designed with focused radiofrequency fields for unilateral breast imaging and spectroscopy tuned for optimized sensitivity at 7 T. T1‐weighted three‐dimensional MRI and 1H MRS were applied for the localization and quantification of total choline compounds. 31P MRSI was obtained within 20 min per subject and mapped in three dimensions over the breast with pixel volumes of 10 mL. The feasibility of monitoring in vivo metabolism was demonstrated in two patients with breast cancer during neoadjuvant chemotherapy, validated by ex vivo high‐resolution magic angle spinning NMR and compared with data from an age‐matched healthy volunteer. Concentrations of total choline down to 0.4 mM could be detected in the human breast in vivo. Levels of adenosine and other nucleoside triphosphates, inorganic phosphate, phosphocholine, phosphoethanolamine and their glycerol diesters detected in glandular tissue, as well as in tumor, were mapped over the entire breast. Altered levels of these compounds were observed in patients compared with an age‐matched healthy volunteer; modulation of these levels occurred in breast tumors during neoadjuvant chemotherapy. To our knowledge, this is the first comprehensive MRI and MRS study in patients with breast cancer, which reveals detailed information on the morphology and phospholipid metabolism from volumes as small as 10 mL. This endogenous metabolic information may provide a new method for the noninvasive assessment of prognostic and predictive biomarkers in breast cancer treatment. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

20.
The expression of cyclooxygenase-2 (COX-2) is observed in approximately 40% of breast cancers. A major product of the COX-2-catalyzed reaction, prostaglandin E(2), is an inflammatory mediator that participates in several biological processes, and influences invasion, vascularization and metastasis. Using noninvasive MRI and MRS, we determined the effect of COX-2 downregulation on the metabolism and invasion of intact poorly differentiated MDA-MB-231 human breast cancer cells stably expressing COX-2 short hairpin RNA. Dynamic tracking of invasion, extracellular matrix degradation and metabolism was performed with an MRI- and MRS-compatible cell perfusion assay under controlled conditions of pH, temperature and oxygenation over the course of 48 h. COX-2-silenced cells exhibited a significant decrease in invasion relative to parental cells that was consistent with the reduced expression of invasion-associated matrix metalloproteinase genes and an increased level of the tissue inhibitor of metalloproteinase-1. We identified, for the first time, a role for COX-2 in mediating changes in choline phospholipid metabolism, and established that choline kinase expression is partly dependent on COX-2 function. COX-2 silencing resulted in a significant decrease in phosphocholine and total choline that was detected by MRS. In addition, a significant increase in lipids, as well as lipid droplet formation, was observed. COX-2 silencing transformed parental cell metabolite patterns to those characteristic of less aggressive cancer cells. These new functional roles of COX-2 may identify new biomarkers and new targets for use in combination with COX-2 targeting to prevent invasion and metastasis.  相似文献   

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