上皮细胞间质转化与肿瘤转移

多种研究表明上皮细胞间质转化(EMT)与上皮细胞恶性肿瘤的发生和发展关系密切。EMT是上皮细胞获得迁移能力的有效方式,在成体中成为占恶性肿瘤90%以上的上皮细胞癌浸润转移的一个重要途径。目前体内和体外实验证据都表明,EMT在乳腺癌、结肠癌、肺癌、前列腺癌、肝癌、胰腺癌等多种癌症的原发性浸润和继发性转移中起着举足轻重的作用。本研究从EMT的分类、生物标记物以及与恶性肿瘤浸润和转移的关系等方面进行综述。     

A549细胞上皮-间质转分化中差异表达基因的生物信息学分析

[背景]在肺纤维化中,上皮-间质转分化(EMT)具有重要的作用.肺泡上皮细胞的EMT是肌成纤维细胞的一个重要来源.而随着高通量测序技术的发展,利用生物信息学的分析筛选EMT过程中的关键基因(Hub基因)引起了学者们的关注.[目的]分析人肺泡Ⅱ型上皮细胞(A549细胞)相关EMT过程中的差异表达基因,以此筛选肺纤维化相关...     

上皮-间质转化与女性生殖系统发育、功能及疾病

上皮-间质转化(epithelial-mesenchymal transition,EMT)是指上皮细胞在形态学上发生向成纤维细胞或间质细胞表型转化的过程,在胚胎发育、组织再生、肿瘤转移和器官纤维化疾病中发挥重要作用。随着EMT在生殖领域不断被发现,EMT作为女性生殖系统的重要调控机制越来越受到关注。本文综述了EMT在女性生殖系统形成、发育及正常功能中的重要性,并讨论EMT在病理状态如子宫内膜异位症、宫腔粘连和生殖系统恶性肿瘤等疾病发生中的作用,以期为女性生殖系统的研究及疾病治疗提供新思路。     

上皮-间质转化与女性生殖系统发育、功能及疾病

上皮-间质转化（epithelial-mesenchymal transition，EMT）是指上皮细胞在形态学上发生向成纤维细胞或间质细胞表型转化的过程，在胚胎发育、组织再生、肿瘤转移和器官纤维化疾病中发挥重要作用。随着EMT在生殖领域不断被发现，EMT作为女性生殖系统的重要调控机制越来越受到关注。本文综述了EMT在女性生殖系统形成、发育及正常功能中的重要性，并讨论EMT在病理状态如子宫内膜异位症、宫腔粘连和生殖系统恶性肿瘤等疾病发生中的作用，以期为女性生殖系统的研究及疾病治疗提供新思路。     

E-cadherin与上皮间质转化的研究进展

<正>上皮间质转化(EMT)是上皮细胞受到细胞外因子刺激后向间质细胞转化的现象,在胚胎发育及肿瘤发生、侵袭和转移中发挥重要作用。EMT的发生与细胞黏附分子E-cadherin表达的降低或缺失密切相关,其过程受多种细胞因子和转录因子调控。本文就E-cadherin与EMT发生及相关调控因子在肿瘤发生、发展中的作用作一综述。     

4种卵巢癌细胞缺氧模型的比较

目的通过比较两种物理和两种化学缺氧方法诱导卵巢癌细胞上皮-间质转化的效果,建立最佳缺氧诱导EMT方法。方法 SKOV3细胞经各种缺氧方法处理24小时后,倒置显微镜观察细胞形态改变,Western blot检测相关蛋白标志物及缺氧诱导因子-1α表达水平的变化。结果厌氧培养袋及三气培养箱缺氧均能诱导SKOV3细胞形态由铺路石样的上皮细胞形态改变为明显的梭形间质细胞形态,并增高缺氧诱导因子-1α及间质细胞标志物波形蛋白（ Vimentin）的表达,降低上皮细胞标志物上皮型-钙粘蛋白（ E-cadherin）的表达,提示发生EMT现象。氯化钴（ CoCl2）及亚硫酸钠（ Na2 SO3）处理24小时后未能诱导SKOV3细胞发生EMT相关细胞形态及标志物表达变化。结论厌氧培养袋和三气培养箱可成功诱导卵巢癌细胞发生EMT。     

中药靶向调控上皮-间质转化干预肺纤维化的研究进展

肺纤维化（pulmonary fibrosis, PF）是慢性进展性肺间质疾病,以渐进性呼吸困难为特点,被称为“不死的癌症”。上皮-间质转化(epithelial-mesenchymal transition,EMT)是完全分化的上皮细胞经过特定程序转化为间充质细胞的生物学过程,对PF的进展有推进作用。大量研究表明,诸多中药单体及活性成分、中药复方可以通过靶向调控EMT干预PF。该文简要阐明EMT内涵,探讨EMT在PF中的作用,研究中医药干预PF中EMT的现状,以期为中医药防治PF提供新思路。     

MicroRNA在肿瘤EMT调控中的作用

MicroRNA(miRNA)是一类长度约19²5个核苷酸的小分子非编码RNA,通过翻译抑制或MRNA降解发挥转录后水平调控基因表达。研究表明,miRNA在上皮细胞-间充质转化(EMT)调控中发挥关键的角色。EMT是上皮细胞通过特定程序转化为具有间质表型细胞的生物学过程,上皮细胞黏附分子如E-钙粘素等表达减少或缺失,细胞失去极性;细胞具有间充质特征,获得了较高的迁移与侵袭能力,间质特征性分子,如Twist、Snail、Slug和Vimentin等表达增高。近年来发现,miRNA参与调控肿瘤细胞发生EMT改变。本文着重对EMT形成过程中miRNA的作用进行扼要综述。此外,回顾分析各种肿瘤中MiRNA的角色,靶向miRNA可能会成为癌症治疗的新型策略。     

TGF-β1诱导乳腺癌细胞EMT的实验研究

目的探索利用TGF-β1诱导乳腺癌细胞MCF-7 EMT水平,并进行生物学验证。方法培养人乳腺癌细胞系MCF-7并传代,使用不同浓度的TGF-β1因子进行诱导,用MTT法检测TGF-β1对乳腺癌细胞的生长促进作用,用实时荧光定量PCR技术对上皮细胞-间质转化的标志物Vimentin表达水平进行检测,利用Transwell小室迁移试验对诱导后的迁移能力进行评估和检测。结果浓度为12.5 ng/ml的TGF-β1诱导MCF-7细胞48 h后细胞形态呈现EMT改变,提示有上皮细胞间质化发生,MTT检测结果显示TGF-β1对乳腺癌细胞MCF-7生长增殖无显著影响,对照组与实验组之间比较,差异无统计学意义(P0.05);EMT间质细胞标志物Vimentin表达上调;Transwell小室迁移试验结果显示,对照组与实验组之间比较,差异有统计学意义(P0.05)。结论人乳腺癌细胞系MCF-7经浓度为12.5 ng/ml的TGF-β1因子诱导48 h后呈现EMT改变,间质化标志物Vimentin表达上调,侵袭转移能力增强。     

p38MAPK信号通路调控二氧化硅诱导的人支气管上皮细胞上皮-间质转型

目的 探讨 p38 MAPK 信号通路在二氧化硅(SiO2)诱导人支气管上皮细胞(human bronchial epithelial cells,HBE)上皮-间质转型(epithelial-mesenchymal transition,EMT)中的作用机制.方法 采用MAPK活性检测试剂盒检测SiO2处理HBE细胞...     

Heavy ions can enhance TGFβ mediated epithelial to mesenchymal transition

TGFβ is a key modulator of the Epithelial-Mesenchymal Transition (EMT), a process important in cancer progression and metastasis, which leads to the suppression of epithelial genes and expression of mesenchymal proteins. Ionizing radiation was found to specifically induce expression of the TGF-β1 isoform, which can modulate late post-radiation changes and increase the risk of tumor development and metastasis. Interactions between TGFβ induced EMT and DNA damage responses have not been fully elucidated, particularly at low doses and following different radiation quality exposures. Further characterization of the relationship between radiation quality, EMT and cancer development is warranted. We investigated whether space radiation induced TGFβ dependent EMT, using hTERT immortalized human esophageal epithelial cells (EPC2-hTERT) and non-transformed mink lung epithelial cells (Mv1Lu). We have observed morphologic and molecular alterations in EPC2 and Mv1Lu cells consistent with EMT after pre-treatment with TGFβ1. This effect could be efficiently inhibited in both cell lines by the use of a TGFβRI inhibitor. High-energy silicon or iron nuclei were each able to cause a mild induction of EMT, with the inclusion of TGFβ1 inducing a greatly enhanced EMT phenotype even when cells were irradiated with doses as low as 0.1 Gy. A further enhancement of EMT was achieved at a higher dose of 2 Gy. TGFβRI inhibitor was able to reverse the EMT induced by the combination of TGFβ1 and radiation. These studies indicate that heavy ions, even at a low dose, may trigger the process of TGFβ1-induced EMT, and suggest further studies are needed to determine whether the chronic exposures received in space may potentiate this process in astronauts, leading to an increased risk of cancer.     

转录因子 KLF4与肿瘤 EMT的分子机制研究进展

上皮间质转化（ EMT）是一种在胚胎发育和损伤修复过程中的生理性改变,其是肿瘤发生和发展过程中的一种常见现象,但作用及机制尚不完全清楚。目前已经发现多个转录因子通过调控下游靶基因参与了EMT的发生过程,其中Krüppel样因子4（KLF4）能够活化上皮基因的表达,同时抑制间质基因的表达,在EMT发生过程中发挥着关键作用,可能是肿瘤治疗的新靶点。该文系统地总结了转录因子KLF4在肿瘤EMT发展过程中的作用及分子机制。     

上皮细胞间充质化在肝脏发育和肝纤维化中的作用

上皮细胞间充质化(EMT)是一个复杂的病理生理过程,受多种信号途径的调节,主要包括Wnt/β-catenin和TGF-β/Smads信号通路.EMT能促进肝细胞以及胆管上皮细胞转化为肝星形细胞,从而导致肝纤维化的进展,此文就其在肝脏发育和肝纤维形成中的作用进行综述.     

3,3′-Diindolylmethane Inhibits TNF-α- and TGF-β-Induced Epithelial–Mesenchymal Transition in Breast Cancer Cells

Epithelial–mesenchymal transition (EMT) is the initial event required by cancer cells. Thus, inhibition of the EMT process could have potential benefits for preventing the spread of cancers. The phytochemicals have been reported to have inhibitory activity against the EMT process in breast cancers, but the mechanism behind this effect has not been fully elucidated.

3,3′-Diindolylmethane (DIM) is a major indole derived from bioactive compounds in cruciferous vegetables. In this study, we examined the effects of DIM cotreatment together with TNF-α/TGF-β on the EMT process as well as the mechanisms underlying its effects on human breast cancer cells. DIM significantly enhanced the mRNA and protein expression of E-cadherin and occludin in MCF-7 cells. The protein expression levels of E-cadherin and occludin in MCF-7 cells were significantly decreased after TNF-α/TGF-β treatment alone, but these effects were reversed by the DIM co-treatment. Furthermore, DIM with TNF-α/TGF-β co-treatment attenuated the phosphorylation of Smad2/3 and ERK1/2 proteins. DIM significantly inhibited the TNF-α/TGF-β-induced migration of breast cancer cells. Taken together, the results indicated that DIM effectively suppressed EMT processes through the inhibition of TNF-α/TGF-β-associated signaling pathways in breast cancer cells. Thus, DIM may be a novel preventive and/or therapeutic approach for the treatment of breast cancers.     

CA125在子宫内膜异位症中的临床意义

目的:通过检测子宫内膜异位症(Endometriosis EMT)患者血清和腹腔液中CA125值,探讨EMT与体液中CA125的关系,寻找EMT诊断与治疗的监测指标。方法:收集腹腔镜确诊为EMT患者30例,据病情分为二组:Ⅰ～Ⅱ期为I组共11例,Ⅲ～Ⅳ期19例为Ⅱ组。收集同期以腹腔镜检查确诊为与EMT无关病例16例,作为Ⅲ组(对照组)。采用电化学发光法测定CA125值。结果:Ⅰ组与Ⅱ组差异无显著性(P>0.05),Ⅱ组与Ⅲ组相比差异有显著性(P<0.05);Ⅰ组与Ⅲ组有显著性差异(P<0.05)。结论:CA125与细胞活性有关,监测腹腔液CA125不但可以早期发现EMT,还可以作为判断病灶活性及治疗效果的一种简单、易行、创伤小、诊断率高的手段。     

Recruitment and retention of emergency medical technicians: a qualitative study

Emergency medical technicians (EMTs) are critical to out-of-hospital care, but maintaining staff can be difficult. The study objective was to identify factors that contribute to recruitment and retention of EMTs and paramedics. Information was drawn from three focus groups of EMT-Basic, EMT-Intermediate, and EMT-Paramedic personnel recruited from participants at an annual conference. Thoughts and feelings of EMTs and paramedics were investigated using eight questions designed to explore entry into emergency medical services, what it is like to be an EMT or paramedic, and the EMT educational process. Data were analyzed at the group level for common themes using NVivo. For a majority of respondents, emergency medical services was not a primary career path. Most respondents entered the industry as an alternate or replacement for a nursing career or as a second career following military medic service. The majority of respondents believed the job was stressful yet rewarding, and although it negatively affected their personal lives, the occupation gave them a sense of accomplishment and belonging. Respondents expressed a preference for EMT education resulting in college credit or licensure versus professional certification. Job-related stress produced by numerous factors appears to be a likely contributor to low employee retention. Recruitment and retention efforts should address study findings, incorporating key findings into educational, evaluation, and job enhancement programs.     

腹腔镜诊断盆腔子宫内膜异位症及对不孕症患者的疗效观察

目的探讨腹腔镜诊断子宫内膜异位症(endometriosis,EMT)病灶的准确性及其与病理诊断的符合率。观察应用腹腔镜治疗EMT引起的不孕症的疗效。方法对180例EMT患者行腹腔镜下病灶切除术,记录EMT病灶在盆腔内的分布特点,并同时对肉眼观察正常的腹膜组织随机活体组织检查。对其中95例不孕症患者比较不同分期术后妊娠率及流产率。结果①180例患者腹腔镜诊断腹膜EMT与病理诊断比较,阳性预测值77.7%,敏感度为90.5%,阴性预测值为86.4%,特异度为41.2%。肉眼观察正常进行腹膜活体组织检查的162份标本中,38例(23.5%)病理检查阳性。EMT病灶在盆腔中的分布以盆腔后半部最多见。②95例不孕症患者术后66例妊娠,各期患者术后累计妊娠率比较,差异有统计学意义(P<0.05);术后24周内妊娠率77.3%(51/66),明显高于术后25周后妊娠率22.7%(15/66),差异有统计学意义(P<0.05)。66例妊娠患者中,流产6例,流产率与EMT分期无关(P>0.05)。结论①腹腔镜下所见的EMT蓝色病灶及宫骶韧带病灶的病理诊断阳性率较高,盆腔EMT病灶的分布呈非对称性,盆腔后部多于前部,左侧多于右侧;②应用腹腔镜可检查、诊断各期EMT及其引起不孕症的盆腔因素,腹腔镜手术治疗可提高EMT患者的妊娠率,且EMT手术后应尽早指导患者妊娠。