BMP4 通过诱导EMT 促进肝癌迁移侵袭*

目的:检测BMP 4 在肝癌中的表达并探讨BMP 4 在诱导肝癌EMT 中的作用,进而研究其对肝癌细胞迁移侵袭能力的影响。方法:采用免疫组织化学方法检测肝癌组织中BMP 4 的表达,分析其与肝癌临床病理资料之间的关系。将BMP 4 表达质粒转染至肝癌细胞系HepG2 中,诱导BMP 4 外源性过表达。观察BMP 4 转染前、后HepG2 的细胞形态学改变;Westernblot检测转染前、后HepG2 中BMP 4、EMT 相关蛋白（E-cadherin、Vimentin）表达变化情况;划痕和侵袭实验检测BMP 4 对细胞迁移侵袭能力的影响。结果:BMP 4 与患者的年龄、病理分级、临床分期、不良预后密切相关。BMP 4 过表达后HepG2 呈现典型的EMT 形态学改变,E-cadherin 表达下调、Vimentin 表达上调、细胞的迁移侵袭能力显著增强。结论:BMP 4 与肝癌临床病理资料密切相关,并可能通过诱导EMT 促进肝癌细胞的迁移侵袭能力。      

TRAF4 Regulates Migration,Invasion, and Epithelial–Mesenchymal Transition via PI3K/AKT Signaling in Hepatocellular Carcinoma

Overexpression of the tumor necrosis factor receptor-associated factor 4 (TRAF4) has been detected in many cancer types and is considered to foster tumor progression. However, the role of TRAF4 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that TRAF4 was highly expressed in HCC cell lines and HCC tissues compared with normal liver cell lines and adjacent noncancerous tissues. TRAF4 overexpression in HCC tissues was correlated with tumor quantity and vascular invasion. In vitro studies showed that TRAF4 was associated with HCC cell migration and invasion. An in vivo study verified that TRAF4 overexpression facilitated metastasis in nude mice. In addition, overexpressed TRAF4 promoted the phosphorylation of Akt and induced Slug overexpression, leading to downregulated E-cadherin and upregulated vimentin, while silencing TRAF4 moderated the phosphorylation of Akt and repressed the expression of Slug, which resulted in upregulated E-cadherin and downregulated vimentin. These effects were inversed after pretreatment of the PI3K/Akt inhibitor LY294002 or overexpression of constitutively active Akt1. Our study demonstrated that TRAF4 was involved in promoting HCC cell migration and invasion. The process was induced by the EMT through activation of the PI3K/Akt signaling pathway.     

miR-186 Represses Proliferation,Migration, Invasion,and EMT of Hepatocellular Carcinoma via Directly Targeting CDK6

The present study aimed to investigate the effect of miR-186 on proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT) of hepatocellular carcinoma (HCC). In this work, miR-186 was downregulated in HCC tissues and cells, and low miR-186 level helped predict the occurrence of vascular invasion and poor prognosis in patients with HCC. miR-186 overexpression inhibited cell proliferation and tumor growth in nude mice, repressed migration and invasion abilities, and enhanced apoptosis in HCC cells. miR-186 also retarded progression of EMT. miR-186 directly bound to the 3 -untranslated regions of cyclin-dependent kinase 6 (CDK6) to inhibit its expression. Overexpression of CDK6 markedly reversed inhibitory effects of miR-186 on proliferation, apoptosis, migration, and invasion of HCC cells. Conversely, inhibition of CDK6 exerted synergic effect on the biological functions of miR-186. In conclusion, miR-186 represses proliferation, migration, invasion, and EMT, and induces apoptosis through targeting CDK6 in HCC, which may provide a new therapeutic target for HCC.     

H2AX磷酸化抑制肺癌细胞发生上皮-间质转化的作用机制

背景 与目的:上皮-间质转化(epithelial-to-mesenchymal transition,EMT)是肿瘤细胞发生转移的关键生物学过程,阻碍EMT将抑制肿瘤转移,因此阐明EMT的分子机制具有重要意义.抑癌蛋白H2AX调控肿瘤细胞凋亡相关基因表达,进而产生抗肿瘤作用.揭示H2AX与EMT的关系,探讨H2AX调...     

Propofol Inhibits Lung Cancer A549 Cell Growth and Epithelial–Mesenchymal Transition Process by Upregulation of MicroRNA-1284

Propofol has been widely used in lung cancer resections. Some studies have demonstrated that the effects of propofol might be mediated by microRNAs (miRNAs). This study aimed to investigate the effects and mechanisms of propofol on lung cancer cells by regulation of miR-1284. A549 cells were treated with different concentrations of propofol, while transfected with miR-1284 inhibitor, si-FOXM1, and their negative controls. Cell viability, migration, and invasion, and the expression of miR-1284, FOXM1, and epithelial–mesenchymal transition (EMT) factors were detected by CCK-8, Transwell, qRT-PCR, and Western blot assays, respectively. In addition, the regulatory and binding relationships among propofol, miR-1284, and FOXM1 were assessed, respectively. Results showed that propofol suppressed A549 cell viability, migration, and invasion, upregulated E-cadherin, and downregulated N-cadherin, vimentin, and Snail expressions. Moreover, propofol significantly promoted the expression of miR-1284. miR-1284 suppression abolished propofol-induced decreases of cell viability, migration, and invasion, and increased FOXM1 expression and the luciferase activity of FOXM1-wt. Further, miR-1284 negatively regulated FOXM1 expression. FOXM1 knockdown reduced cell viability, migration, and invasion by propofol treatment plus miR-1284 suppression. In conclusion, our study indicated that propofol could inhibit cell viability, migration, invasion, and the EMT process in lung cancer cells by regulation of miR-1284.     

MicroRNA-200a Suppresses Cell Invasion and Migration by Directly Targeting GAB1 in Hepatocellular Carcinoma

MicroRNA-200a (miR-200a) is frequently downregulated in most cancer types and plays an important role in carcinogenesis and cancer progression. In this study, we determined that miR-200a was downregulated in hepatocellular carcinoma (HCC) tissues and cell lines, consistent with the results of our previous study. Because a previous study suggested that downregulation of miR-200a is correlated with HCC metastasis, we aimed to elucidate the mechanism underlying the role of miR-200a in metastasis in HCC. Here we observed that overexpression of miR-200a resulted in suppression of HCC metastatic ability, including HCC cell migration, invasion, and metastasis, in vitro and in vivo. Furthermore, bioinformatics and luciferase reporter assays indicated that GAB1 is a direct target of miR-200a. Inhibition of GAB1 resulted in substantially decreased cell invasion and migration similar to that observed with overexpression of miR-200a in HCC cell lines, whereas restoration of GAB1 partially rescued the inhibitory effects of miR-200a. Taken together, these data provide novel information for comprehending the tumor-suppressive role of miR-200a in HCC pathogenesis through inhibition of GAB1 translation.     

NTS/IL-8通路对肝细胞肝癌侵袭迁移和EMT的影响

  目的  探讨神经降压素（neurotensin,NTS）对肝细胞肝癌（hepatocellular carcinoma,HCC）细胞合成和分泌白细胞介素8（interleukin-8,IL-8）的影响及NTS/IL-8通路活化对HCC侵袭、迁移和上皮间质转化（epithelial-mesenchymal transition,EMT）的作用。  方法  通过慢病毒基因转染构建神经降压素受体1（neurotensin receptor1,NTR1）高表达的HCC细胞系Hep3BNTR1hi,利用小干扰RNA构建NTR1低表达HCC细胞系HepG2NTR1-。通过实时荧光定量PCR（RT-qPCR）和酶联免疫吸附（ELISA）实验检测外源性NTS刺激前后HCC细胞IL-8分泌量的变化;利用划痕修复实验和Transwell实验观察阻断IL-8受体后HCC细胞侵袭迁移能力的变化;采用Western blot比较阻断IL-8受体后HCC细胞EMT相关蛋白的表达变化。  结果  外源性NTS刺激和高表达NTR1可促进Hep3B和HepG2细胞合成和分泌IL-8（P均 < 0.01）,阻断或降低NTR1表达后IL-8的表达显著降低（P < 0.05,P < 0.01）。外源性NTS刺激和高表达NTR1可提高HCC细胞的侵袭和迁移能力（P均 < 0.05）,阻断IL-8受体,即阻断NTS/IL-8信号下传,HCC细胞的划痕修复率和侵袭细胞数均降低（P均 < 0.001）,同时伴有E-cadherin表达增加,N-cadherin、β-catenin表达降低。  结论  外源性NTS刺激和高表达NTR1可以刺激HCC细胞合成和分泌IL-8,阻断NTS/IL-8信号下传会降低肝癌细胞EMT和侵袭迁移能力。      

lncRNA MEG3 通过miR-9-5p/SOCS5 轴对宫颈癌细胞恶性生物学行为的影响

目的：探讨lncRNA 母源性印记基因3（maternal imprinting gene 3, MEG3）通过miR-9-5p/SOCS5 轴对宫颈癌细胞增殖、迁移、侵袭和上皮间质转化（epithelial-mesenchymal transition, EMT）的调控作用。方法: 收集2017 年1 月至2019 年6 月重庆市中医院手术切除的20 例宫颈癌患者的癌及癌旁组织标本;利用脂质体转染技术分别将pcDNA3.1-MEG3、si-MEG3、miR-9-5p mimics、miR-9-5p inhibitor 及其对照质粒等转染进宫颈癌HeLa 和SiHa 细胞,构建过表达和沉默细胞模型。用qPCR检测宫颈癌组织及细胞模型中MEG3、miR-9-5p 和SOCS5 表达水平,用CCK-8 法、Transwell 小室法检测细胞的增殖、迁移和侵袭能力,用细胞免疫荧光实验检测细胞中E-cadherin 和vimentin 表达水平。通过在线生物信息学TargetScan 数据库预测靶基因,用双荧光素酶报告基因实验验证miR-9-5p 分别与MEG3 和SOCS5 的靶向关系。结果: 分别与癌旁组织和宫颈上皮HcerEpic 细胞比较,宫颈癌组织和细胞系中MEG3 和SOCS5 表达显著下调、miR-9-5p 表达显著上调（均P<0.01）。TargetScan 数据库分析和双荧光素酶报告基因实验证实miR-9-5p 与MEG3 或SOCS5 存在靶向关系。MEG3 和SOCS5 显著抑制宫颈癌细胞的增殖、迁移与侵袭能力（均P<0.01）,miR-9-5p 显著提高细胞的增殖、迁移与侵袭能力（均P<0.01）。MEG3 和SOCS5 促进E-cadherin 表达、抑制vimentin表达;miR-9-5p 抑制E-cadherin 表达、促进vimentin 表达（P<0.05 或P<0.01）。结论: lncRNA MEG3 通过miR-9-5p/SOCS5 分子轴调控宫颈癌细胞的增殖、迁移、侵袭与EMT进程。     

LncRNA SNHG6调控miR-186表达对肝癌细胞增殖、迁移和侵袭的影响及机制

目的:研究SNHG6通过调控miR-186表达对人肝癌细胞增殖、迁移、侵袭和上皮间质转化（EMT）的影响。方法:通过实时荧光定量PCR（RT-qPCR）检测57名肝癌患者癌组织和肝癌细胞系中SNHG6和miR-186的表达;双荧光素酶报告实验验证SNHG6和miR-186的靶向调控关系;将SNHG6的小干扰RNA（si-SNHG6组）、阴性无意义对照序列（si-con组）、si-SNHG6与anti-miR-186抑制剂（si-SNHG6+anti-miR-186组）、si-SNHG6与miR-186抑制物阴性对照（si-SNHG6+anti-miR-con组）,均以脂质体法转染至肝癌HepG2细胞,MTT法检测细胞增殖;Transwell检测肝癌细胞迁移和侵袭;Western blot实验检测肝癌细胞CDK4、Cyclin D1、MMP-2、MMP-9及EMT的标志物（E-cadherin、N-cadherin和Vimentin）表达。结果:与癌旁正常组织或正常肝细胞相比,SNHG6在肝癌患者和肝癌细胞系中的表达升高,而miR-186表达降低,两者存在负相关性。与si-con组比较,si-SNHG6组HepG2细胞活力明显下降,迁移和侵袭细胞数明显减少,CDK4、Cyclin D1、MMP-2、MMP-9、N-cadherin和Vimentin蛋白表达降低,E-cadherin蛋白表达增加。SNHG6靶向负调控miR-186表达,抑制miR-186表达可部分逆转下调SNHG6对HepG2细胞增殖、迁移和侵袭的抑制作用。结论:下调SNHG6可能通过负调控miR-186表达和调控细胞EMT过程抑制肝癌细胞的增殖、迁移和侵袭。     

miR-202 Suppresses Hepatocellular Carcinoma Progression via Downregulating BCL2 Expression

miRNAs play an important role in progression of hepatocellular carcinoma (HCC). In this work, we assessed the function of miR-202 in human HCC and identified BCL2 as its target. We found miR-202 expression was found significantly downregulated, while BCL2 expression was markedly upregulated in HCC tissues and cell lines (HepG2, Hep3B, and HCCLM3). Both miR-202 and BCL2 were closely correlated with major vascular invasion and advanced TNM stage as well as overall survival of HCC patients. Overexpression of miR-202 significantly inhibited cell proliferation, induced apoptosis and cell cycle arrest at the G0/G1 phase, and prevented tumor formation in a xenograft nude mouse model. Further, miR-202 dramatically inhibited migration, invasion, and epithelial–mesenchymal transition. miR-202 bound to the 3 -untranslated region (3 -UTR) of BCL2 mRNA and downregulated the expression level of BCL2 protein. Exogenous BCL2 overexpression weakened the inhibitory effects of miR-202, while inhibition of BCL2 enhanced the inhibitory effects of miR-202. In conclusion, miR-202 serves as a tumor suppressor in HCC progression by downregulating BCL2 expression, indicating miR-202 might be a potential target for HCC.     

Ectopic Expression of miR-147 Inhibits Stem Cell Marker and Epithelial–Mesenchymal Transition (EMT)-Related Protein Expression in Colon Cancer Cells

Colon cancer is one of the most common cancers in the world. Epithelial-to-mesenchymal transition (EMT) is a crucial step in tumor progression and is also involved in the acquisition of stem cell-like properties. Some miRNAs have been shown to function as either tumor suppressors or oncogenes in colon cancer. Here we investigated the role of miR-147 in the regulation of the stem cell-like traits of colon cancer cells. We observed that miR-147 was downregulated in several colon cancer cell lines, and overexpressed miR-147 decreased the expression of cancer stem cell (CSC) markers OCT4, SOX2, and NANOG in the colon cancer cell lines HCT116 and SW480. Overexpressed miR-147 inhibited EMT by increasing the expression of epithelial markers E-cadherin and -catenin while decreasing the expression of mesenchymal markers fibronectin and vimentin. Moreover, activation of EMT by TGF- 1 treatment significantly counteracted the inhibitive effect of miR-147 on the expression of CSC markers OCT4, SOX2, and NANOG, supporting the idea that overexpressing miR-147 inhibited stem cell-like traits by suppressing EMT in colon cancer. In addition, we found that overexpressed miR-147 downregulated the expression of -catenin, c-myc, and survivin, which were related to the Wnt/ -catenin pathway. Moreover, treatment of miR-147 mimic-transfected cells with the Wnt/ -catenin pathway activator LiCl attenuated the inhibitive effect of the miR-147 mimic on the EMT and stem cell-like traits of colon cancer cells, indicating that ectopic expression of miR-147 inhibited stem cell-like traits in colon cancer cells by suppressing EMT via the Wnt/ -catenin pathway. In summary, our present study highlighted the crucial role of miR-147 in the inhibition of the stem cell-like traits of colon cancer cells and indicated that miR-147 could be a promising therapeutic target for colon cancer treatment.     

MicroRNA-29a靶向抑制PTEN基因诱导非小细胞肺癌细胞上皮间质转化的机制研究

目的:探讨microRNA-29a（miR-29a）及其靶蛋白PTEN在TGF-β1诱导非小细胞肺癌（non-small cell lung cancer,NSCLC）细胞上皮间质转化（epithelial-mesenchymal transition,EMT）中的作用机制。方法:选择A549细胞经终浓度为10 ng/ml TGF-β1诱导48 h后,分为Blank组（不转染任何序列）、阴性对照（negative control,NC）组（转染阴性对照序列）、IN组（转染miR-29a inhibitors）、siRNA组（转染PTEN-siRNA）和IN+siRNA组（共转染miR-29a inhibitors和PTEN-siRNA）。普通显微镜观察各组细胞形态学变化;免疫荧光检测各组细胞中E-cadherin表达水平;qRT-PCR法检测EMT相关因子及PTEN mRNA表达水平;Western blotting法检测转染后EMT相关因子、PTEN、Akt和p-Akt蛋白的表达;划痕实验检测各组细胞迁移能力。构建裸鼠移植瘤模型,观察肿瘤生长,免疫组化检测裸鼠肿瘤组织中PTEN及EMT相关因子蛋白表达水平。结果:A549细胞转染miR-29a inhibitors后TGF-β1诱导细胞的上皮间质转化显著受到抑制,N-cadherin、Vimentin及Slug的mRNA和蛋白表达水平在IN组中显著低于Blank组和NC组,但在siRNA组和IN+siRNA组中显著上调（均P<0.05）。与Blank组和NC组相比,IN组PTEN mRNA和蛋白表达水平明显升高,且p-Akt的表达显著降低,细胞迁移率显著下降,而siRNA组和IN+siRNA组PTEN mRNA和蛋白表达明显降低,p-Akt的表达显著上升,细胞迁移率显著升高（均P<0.05）。裸鼠移植瘤实验结果显示与Blank组和NC组相比,IN组肿瘤生长较慢,重量降低,E-cadherin和PTEN蛋白表达显著升高,N-cadherin、β-catenin、Vimentin、Slug蛋白表达显著降低（均P<0.05）。结论:TGF-β1能诱导NSCLC细胞发生EMT,且能上调miR-29a并抑制PTEN的表达水平;抑制miR-29a的表达水平可能通过上调靶基因PTEN,促进Akt磷酸化,抑制EMT的发生。     

MicroRNA-451: epithelial-mesenchymal transition inhibitor and prognostic biomarker of hepatocelluar carcinoma

Increasing evidence indicates that dysregulation of microRNAs (miRNAs) plays critical roles in malignant transformation and tumor progression. Previously, we have shown that microRNA-451 (miR-451) inhibits growth, increases chemo- or radiosensitivity and reverses epithelial to mesenchymal transition (EMT) in lung cancer. However, the roles of miR-451 in hepatocelluar carcinoma (HCC) progression and metastasis are still largely unknown. Reduced miR-451 in HCC tissues was observed to be significantly correlated with advanced clinical stage, metastasis and worse disease-free or overall survival. Through gain- and loss-of function experiments, we demonstrated that miR-451 inhibited cell growth, induced G0/G1 arrest and promoted apoptosis in HCC cells. Importantly, miR-451 could inhibit the migration and invasion in vitro, as well as in vivo metastasis of HCC cells through regulating EMT process. Moreover, the oncogene c-Myc was identified as a direct and functional target of miR-451 in HCC cells. Knockdown of c-Myc phenocopied the effects of miR-451 on EMT and metastasis of HCC cells, whereas overexpression of c-Myc partially attenuated the functions of miR-451 restoration. Furthermore, miR-451 downregulation-induced c-Myc overexpression leads to the activation of Erk1/2 signaling, which induces acquisition of EMT phenotype through regulation of GSK-3β/snail/E-cadherin and the increased expression of MMPs family members in HCC cells. Collectively, these data demonstrated that miR-451 is a novel prognostic biomarker for HCC patients and that function as a potential metastasis inhibitor in HCC cells through activation of the Erk1/2 signaling, at least partially by targeting c-Myc. Thus, targeting miR-451/c-Myc/Erk1/2 axis may be a potential strategy for the treatment of metastatic HCC.     

miR-506通过调控MCL-1抑制耐阿立替尼非小细胞肺癌A549细胞上皮间质转化的作用机制

目的:探究miR-506通过调控MCL-1对耐阿立替尼非小细胞肺癌A549细胞上皮间质转化（epithelial mesenchymal transformation,EMT）及侵袭转移的影响和作用机制。方法:收集2017年12月至2018年12月我院肿瘤科收治的经PET-CT结合组织病理活检及药敏试验确诊为耐阿立替尼的74例非小细胞肺癌患者的癌及癌旁组织以及人非小细胞肺癌A549细胞为研究对象,分别采用细胞转染、免疫组化染色（IHC）、qRT-PCR和Western Blot法检测上述临床组织和细胞样本中miR-506、MCL-1、BAX/Bcl-2凋亡信号途径及EMT标志蛋白表达水平;此外,采用Transwell细胞实验观察miR-506过表达和MCL-1敲减对A549细胞迁移和侵袭能力的影响。结果:免疫组化（IHC）结果显示肺癌患者癌组织中浸润性坏死性病理损伤较癌旁组织明显加重,且癌组织中MCL-1的阳性表达率为94.64%,明显高于癌旁组织的23.27%（P＜0.05）。qRT-PCR和Western Blot结果显示,肺癌组织中miR-506、BAX和E-cadherin的表达明显低于癌旁组织,而MCL-1、Bcl-2和N-cadherin的表达显著高于癌旁组织（P＜0.05）。细胞实验结果表明miR-506过表达和MCL-1敲减能够明显上调BAX和E-cadherin的表达,同时抑制Bcl-2和N-cadherin的表达（P＜0.05）;此外,miR-506过表达和MCL-1敲减均能显著抑制肺癌A549细胞的迁移和侵袭能力（P＜0.05）。结论:miR-506可能通过抑制BAX/Bcl-2/MCL-1凋亡途径发挥抑制耐阿立替尼非小细胞肺癌A549细胞EMT及诱导细胞凋亡作用,有望为临床抗肺癌转移及凋亡抑制靶向治疗提供新分子和靶点。     

小核核糖核蛋白多肽A对肝细胞癌细胞恶性生物学行为的影响及其机制

目的：探究小核核糖核蛋白多肽A（SNRPA）在肝细胞癌（HCC）组织和细胞中的表达及其调控HCC 细胞HepG2 和Hep3B恶性生物学行为的作用及其机制。方法: 数据库分析SNRPA在泛癌组织中的表达及其与病理分期、HCC 患者预后的相关性。常规培养HepG2 和Hep3B 细胞，将si-NC ，si-SNRPA#1、si-SNRPA#2转染HepG2 和Hep3B 细胞，实验分为si-NC 组、 si-SNRPA#1 组和si-SNRPA#2 组；将SNRPA-vector 和SNRPA-oe 载体转染LO2 细胞，分为SNRPA-vector 组和SNRPA-oe 组。 qPCR法检测正常肝细胞和肝癌细胞以及转染各组HepG2和Hep3B细胞中SNRPA mRNA的表达，MTT法、Transwell 法和WB法分别检测转染后各组HepG2 和Hep3B细胞的增殖、迁移和侵袭能力以及EMT相关蛋白表达的变化。结果: 数据库分析显示，SNRPA mRNA在多数肿瘤组织中均呈高表达（均P<0.001）且与病理分期有关联（P<0.05或P<0.01）。SNRPA在HCC组织和细胞中均呈高表达（P<0.05 或P<0.01），且与HCC患者的预后有关联（P<0.01）。敲减SNRPA表达明显抑制HepG2 和Hep3B细胞增殖（P<0.05或P<0.01）而过表达SNRPA则能促进LO2细胞增殖（P<0.01），敲减SNRPA表达明显抑制HepG2和Hep3B细胞的迁移和侵袭能力（均P<0.01），明显促进E-cadherin 的表达上调（P<0.01），而抑制N-cadherin、vimentin 的表达（P<0.01）。结论: SNRPA在HCC组织及细胞中呈明显高表达，其可能通过调控上皮间质转化（EMT）进程进而促进HepG2和Hep3B细胞的增殖、迁移和侵袭。     

microRNA-148a suppresses human gastric cancer cell metastasis by reversing epithelial-to-mesenchymal transition

MicroRNAs (miRNAs) are important regulators of gastric cancer development and progression. miR-148a is one of the most frequently and highly downregulated miRNAs in gastric cancer and is associated with advanced clinical stage and poor prognosis. In this study, we investigated the role of miR-148a in gastric cancer metastasis. Levels of miR-148a were determined by qRT-PCR in 60 gastric cancer samples. Cell migration and invasion assays were performed in a stably expressing miRNA-148a gastric cancer cell line established using a lentivirus expression system. Epithelial–mesenchymal transition (EMT) was evaluated using qRT-PCR and Western Blots to detect epithelial marker E-cadherin and mesenchymal marker, vimentin. Luciferase reporter assays were used to identify downstream targets and biological function of miR-148a. Gastric cancer tissue had significantly lower expression of miR-148a compared to non-tumor tissue. Low miR-148a levels were associated with lymph node metastasis, N stage, and blood vessel invasion. miR-148a overexpression inhibited metastasis of gastric cancer cells. miR-148a overexpression also downregulated vimentin expression and upregulated E-cadherin expression, suggesting that miR-148a inhibited EMT. Finally, the SMAD2 gene was identified as the direct and functional target of miR-148a. MiR-148a suppresses gastric cancer metastasis and EMT, likely via SMAD2. Restoration of miR-148a expression could have important implications in gastric cancer therapy.     

萝卜硫素对小鼠乳腺癌4T1细胞上皮-间质转化、增殖和迁移的影响研究

背景与目的：组蛋白去乙酰化酶5（histone deacetylase 5,HDAC5）在乳腺癌组织中异常高表达,其与赖氨酸特异性去甲基化酶1（lysine specific demethylase,LSD1）协同促进乳腺癌细胞增殖和迁移。通过萝卜硫素（sulforaphane,SFN）下调HDAC5表达,观察其对小鼠乳腺癌4T1细胞上皮-间质转化（epithelial-mesenchymal transition,EMT）、增殖和迁移的影响。方法：采用细胞计数试剂盒-8（cell counting kit-8,CCK-8）法分析SFN对4T1细胞增殖的影响。采用乳酸脱氢酶释放实验检测SFN的细胞毒性。采用pcDNA3.1(+)-FLAG-HDAC5质粒转染4T1细胞,通过G418筛选获得单个细胞克隆,再以蛋白质印迹法（Western blot）鉴定HDAC5蛋白稳定高表达的单克隆细胞系。采用划痕实验和transwell法分析过表达HDAC5以及SFN处理对4T1细胞迁移和侵袭的影响。采用Western blot检测SFN处理对4T1细胞EMT标志物上皮钙黏着蛋白（E-cadherin）、神经钙黏着蛋白（N-cadherin）、波形蛋白（vimentin）和基质金属蛋白酶-9（matrix metalloproteinase-9,MMP-9）表达的影响。以4T1细胞的BALB/c小鼠移植瘤为模型,观察SFN对4T1细胞体内成瘤性、转移的影响及其与HDAC5表达的关系。采用免疫组织化学法检测小鼠原位肿瘤及肺转移瘤组织中Ki-67增殖指数。取荷瘤小鼠心、肝、肾组织,采用H-E染色检测SFN对荷瘤小鼠的毒性作用。结果：SFN能够抑制4T1细胞增殖（P＜0.01）,并抑制4T1细胞体外迁移和侵袭,而外源性过表达HDAC5可部分拮抗SFN对4T1细胞迁移和侵袭的抑制作用。SFN处理显著下调4T1细胞中HDAC5、MMP-9、N-cadherin和vimentin的表达,同时上调E-cadherin的表达。结论：SFN处理显著抑制4T1细胞在小鼠体内的成瘤性和肺转移,下调小鼠原位肿瘤和肺转移瘤组织中的Ki-67阳性率。过表达HDAC5可拮抗SFN对4T1细胞体内成瘤性和肺转移的抑制作用。SFN的抗乳腺癌作用与其诱导的HDAC5表达下调以及由此介导的EMT抑制作用密切相关。     

miR-186 Suppresses the Progression of Cholangiocarcinoma Cells Through Inhibition of Twist1

Deregulation of miR-186 and Twist1 has been identified to be involved in the progression of multiple cancers. However, the detailed molecular mechanisms underlying miR-186-involved cholangiocarcinoma (CCA) are still unknown. In this study, we found that miR-186 was downregulated in CCA tissues and cell lines, and negatively correlated with the expression of Twist1 protein. In vitro assays demonstrated that miR-186 mimics repressed cell proliferation, in vivo tumor formation, and caused cell cycle arrest. miR-186 mimics also inhibited the migration and invasion of CCLP1 and SG-231 cells. Mechanistically, the 3′-untranslated region (3′-UTR) of Twist1 mRNA is a direct target of miR-186. Further, miR-186 inhibited the expressions of Twist1, N-cadherin, vimentin, and matrix metallopeptidase 9 (MMP9) proteins, whereas it increased the expression of E-cadherin in CCLP1 and SG-231 cells. Silencing of Twist1 expression enhanced the inhibitory effects of miR- 186 on the proliferation, migration, and invasion of CCLP1 and SG-231 cells. In conclusion, miR-186 inhibited cell proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT) through targeting Twist1 in human CCA. Thus, miR-186/Twist1 axis may benefit the development of therapies for CCA.