miR-134 inhibits epithelial to mesenchymal transition by targeting FOXM1 in non-small cell lung cancer cells

Recent studies have implied that miRNAs act as crucial modulators for epithelial-to-mesenchymal transition (EMT). We found that miR-134 expression correlated with invasive potential and EMT phenotype of NSCLC cells. Functional assays demonstrated that miR-134 inhibited EMT in NSCLC cells. In addition, we showed that Forkhead Box M1 (FOXM1) is a direct target of miR-134. Knockdown of FOXM1 reversed EMT resembling that of miR-134 overexpression. We further found that FOXM1 was involved in TGF-β1-induced EMT in A549 cells. These findings suggest that miR-134 acts as a novel EMT suppressor in NSCLC cells.     

KDM5D inhibit epithelial-mesenchymal transition of gastric cancer through demethylation in the promoter of Cul4A in male

Gastric cancer is one of the top causes of cancer-related death around the world, and poor prognosis of gastric cancer is due to the lack of early detection and effective treatment especially in male. Here, we first revealed the role of histone lysine-specific demethylase 5D (KDM5D) in gastric cancer in male. KDM5D was associated with the metastasis of gastric cancer because of its critical role in the epithelial-mesenchymal transition of gastric cancer cells. Downregulation of KDM5D in gastric cancer cells significantly increase the number of migrated or invaded cells due to the increasing expressions of mesenchymal markers. Downregulation of KDM5D also promotes tumor formation of gastric cancer cell in vivo. For mechanism, downregulation of KDM5D could inhibit the demethylation in the promoter of CUL4A, which lead to the increasing expression of ZEB1 and decreasing expressions of p21 and p53. Collectively, KDM5D performed its role in metastasis of gastric cancer through demethylation in the promoter of CUL4A, and it suggested us a novel target in gastric cancer treatment in male.     

Epigenetic biomarkers in colorectal cancer: premises and prospects

Context: Colorectal cancer is one of the most common cancers worldwide. Epigenetic alterations play an important role in the pathogenesis of the colorectal cancer.

Objective: This review has focused on the most recent investigations, which has suggested potential epigenetic biomarkers in colorectal cancer.

Methods: Evidences were achieved by searching online medical databases including Google scholar, Pubmed, Scopus and Science Direct.

Results: Extensive studies have indicated that aberrant epigenetic modifications could serve as potential biomarkers for diagnosis, prognosis and prediction of colorectal cancer.

Conclusion: Advances in aberrant epigenetic modifications can open new avenues for exploration of reliable and robust biomarkers to improve the management of CRC patients.     

Scutellarin inhibits hypoxia-induced epithelial-mesenchymal transition in bladder cancer cells

Scutellarin, an active component of flavonoid, displays a variety of physiological actions and has been applied for the treatment of diverse diseases including hypertension and cerebral infarction as well as cerebral thrombosis. In recent time, Scutellarin has been demonstrated to possess the anticancer activity. But the biological significance of Scutellarin in bladder cancer (BC) remains to be elucidated. In the current study, we explored the specific effect of Scutellarin on BC progression. We found that Scutellarin inhibited hypoxia-induced BC cell migration and invasion in vitro as well as suppressed hypoxia-induced BC metastasis in vivo. Moreover, Scutellarin significantly reversed hypoxia-promoted epithelial-mesenchymal transition (EMT) in BC cells and the PI3K/Akt and MAPK pathways were implicated in the suppressive effect. Taken together, we suggested the potential value of Scutellarin as a novel anticancer agent for BC treatment.     

The clinical significance of circulating miR-21, miR-142, miR-143, and miR-146a in patients with prostate cancer

BackgroundProstate cancer (PCa) is the most common type of solid tissue cancer among men in western countries. In this study, we determined the levels of circulating miR-21, miR-142, miR-143, miR-146a, and RNU 44 levels as controls for early diagnosis of PCa.MethodsThe circulating miRNA levels in peripheral blood samples from 43 localized PCa patients, 12 metastatic PCa (MET) patients, and a control group of, 42 benign prostate hyperplasia (BPH) patients with a total of 97 volunteers were determined the by PCR method.ResultsNo differences in the DCT values were found among the groups. In PCa and PCaMet groups the expression of miR21 and miR142 were higher compared to the BHP group. No other differences were observed among the other groups. miR21 expression in the PCa group was 6.29 folds upregulated whereas in the PCaMet group 10.84 folds up-regulated. When the total expression of miR142 is evaluated, it showed a positive correlation with mir21 and mir 146 (both p<0.001). Also, the expression of miR146 shows a positive correlation with both miR21 and miR143 (both p<0.001). Expression of miRNAs was found to be an independent diagnostic factor in patients with Gleason score, PSA, and free PSA levels.ConclusionsOur study showed that co-expression of miR21, miR-142, miR-143, and miR-146a and the upregulation of miR-21 resulted in increased prostate carcinoma cell growth. In the PCaMet group, miR21 is the most upregulated of all miRNAs. These markers may provide a novel diagnostic tool to help diagnose PCa with aggressive behavior.     

去泛素化酶在肿瘤上皮间质转化中的作用

肿瘤的侵袭和转移是加剧肿瘤恶化的主要原因,也是导致患者预后不良的根本原因。近年来大量研究发现,大部分肿瘤的转移都依赖于上皮间质转化(epithelial-mesenchymal transition, EMT)的发生,此外EMT也与肿瘤干性和肿瘤耐药等诸多肿瘤恶性行为密切相关,因此有效的抑制EMT的发生将可能极大的有利于肿瘤的治疗。去泛素化酶(deubiquitinating enzymes, DUBs)的主要功能之一就是通过移除底物蛋白质上泛素链,避免其通过泛素蛋白酶体途径降解,来维持细胞内蛋白质水平的动态平衡。去泛素化酶作为调节蛋白质泛素化修饰的一类重要酶类,其异常表达或酶活性的改变通常都会导致疾病的发生。众多研究发现,部分去泛素化酶在肿瘤侵袭和转移过程中表达失衡,在肿瘤转移的过程中扮演着重要的角色。EMT是指由上皮型细胞转变为间质型细胞的动态细胞生物学过程,在该过程中涉及到例如Snial1、Slug、ZEB1等EMT相关转录因子和细胞表面的例如E-钙黏着蛋白、N-钙黏着蛋白等分子标志物表达水平的变化。这些蛋白质通常具有不稳定性,易被降解等特征。EMT过程的发生,涉及到许多蛋白质稳定性的调节,而去泛素化酶作为一类维持蛋白质稳定的重要酶类,在调节这些蛋白质的稳定性方面发挥着重要的作用。EMT的发生也与TGF-β通路、Wnt通路等细胞内众多信号通路的异常活化密不可分,去泛素化酶通过介导这些信号通路的活化,从而间接的调节EMT发生发展。去泛素化酶通过调节EMT相关分子或EMT相关信号通路等多种方式直接或间接影响EMT进展,因此,通过靶向于去泛素化酶抑制肿瘤的侵袭和转移,将为肿瘤治疗提供新的治疗手段和方案,从而有效的推动肿瘤的治疗。本文主要就去泛素化酶在调节EMT相关分子以及信号通路等方面,阐述去泛素化酶在EMT过程中所发挥的重要作用及其作为肿瘤治疗靶点的可能性。     

沉默FOXQ1可逆转SW480细胞的上皮-间质转化

FOXQ1是FOX家族的的重要成员之一,其参与了多种人类肿瘤的上皮间质转化(epithelial- mesenchymal transition,EMT).本研究设计合成了FOXQ1基因的shRNA（short hairpin RNA）,用此转染SW480细胞,通过显微镜观察细胞形态,Transwell小室、细胞黏附试验检测转移能力及黏附能力,以探索FOXQ1与结直肠癌细胞EMT的关系.结果显示,沉默FOXQ1后,SW480细胞顶底极性及细胞间紧密连接增加,侵袭、迁移的细胞数目减少,同种黏附能力增加,异种黏附能力降低.进一步的机制研究表明,沉默FOXQ1基因可以导致SW480细胞的上皮标志因子E-cadherin表达显著增高,而间质细胞标志因子N-cadherin、Vimentin及MMP2表达均降低.以上结果表明,沉默FOXQ1基因可以逆转SW480细胞EMT,其机制可能与E-cadherin的上调和N cadherin、Vimentin、MMP2的下调有关,这为进一步研究FOXQ1在结直肠癌发生发展中的作用提供实验基础.     

用生物传感器方法测定正常小鼠肝脏中miR-21活性

目的:建立生物传感器检测小鼠肝脏中microRNA (miRNA)活性的方法,测定miR-21在正常小鼠肝脏中的活性。方法:首先,分子克隆方法构建检测miRNA活性的通用型质粒传感器Dsensor。将各种miRNA的互补序列插入Dsensor中构建成相应miRNA活性检测传感器。用水动力法将检测miR-21的Dsensor注射至正常小鼠体内,以miR-122 Dsensor为阳性对照,miR-206 Dsensor为阴性对照,以不插入任何miRNA互补序列的Dsensor为空白对照。不同时间点尾静脉采血测定Gluc表达,处死小鼠测定肝脏中Fluc表达,比较计算得出miRNA活性。最后,用QRT-PCR法测定小鼠肝脏组织中miR-21、miR-122和miR-206表达水平。结果:用RIF(Relative inhibiting fold)值表示miRNA活性,miR-21、miR-122和miR-206活性分别为80.03±21.25,29.90±5.90和0.92±0.29,表明小鼠正常肝脏中miR-21的负调控活性明显高于miR-122。然而,QRT-PCR法测定结果显示,miR-21的表达水平明显低于miR-122,而miR-206几乎没有表达。从miR-21与miR-122的活性与表达水平比较发现,miR-21的表达水平并没有真实反映其活性。结论:成功建立了一种小鼠肝脏中miRNA活性检测方法;首次发现小鼠正常肝脏中miR-21活性水平比miR-122更高,而表达水平却明显低于miR-122。提示miR-21对于维持肝脏的正常生理功能的重要作用,值得进一步研究其调控的靶基因和机理。     

Role of miR-21 and its signaling pathways in renal diseases

Abstract

miRNAs are endogenous non-coding RNAs that are ～22 nucleotides in length and can have structural, enzymatic and regulatory functions. miRNAs play important roles in the progression of renal fibrosis. miR-21, through a feed-forward loop and a downstream mediator of transforming growth factor-β (TGF-β), amplifies TGF-β signaling and promotes fibrosis. miR-21 is high on the list of non-coding, small, regulatory RNAs that promote renal fibrosis and emerges as a serum biomarker for kidney diseases, but many questions await answers. This review was performed to sum up the role of miR-21 and its signaling pathways in renal diseases.     

MiR-150-5p通过靶向调控Rab1A抑制乳腺癌细胞MDA-231的上皮-间质转化

先前的研究表明,miR-150-5p发挥抑癌基因的作用,调控肿瘤细胞的侵袭与转移。然而,关于其在乳腺癌细胞侵袭与转移中的机制尚不明确。本实验旨在研究miR-150-5p负向调控Rab1A在乳腺癌细胞上皮-间质转化（epithelial-mesenchymal transition,EMT）中的作用。双荧光素酶的结果显示,miR-150-5p可负向调控Rab1A。荧光定量PCR (qRT-PCR) 结果显示,miR-150-5p在乳腺癌细胞MCF-7及MDA-MB-231（MDA-231）中的表达水平明显低于正常乳腺上皮细胞MCF-10A; 在MDA-231中过表达miR-150-5p后,qRT-PCR结果显示,Rab1A mRNA的表达水平明显降低。Western印迹结果显示,过表达miR-150-5p后,miR-150-5p组细胞中的Rab1A、波形蛋白(vimentin)及N-钙黏着蛋白(N-cadherin)的表达水平相对于对照组（NC）细胞明显降低,而E-钙黏着蛋白(E-cadherin)的表达水平明显增加。Transwell侵袭和划痕实验显示,与miR-150-5p+Con组细胞相比,miR-150-5p+Rab1A组细胞的侵袭和迁移能力明显增加。qRT-PCR结果显示,miR-150-5p+Rab1A组细胞的Rab1A mRNA表达水平明显增加。Western印迹结果显示,miR-150-5p+Rab1A组细胞中的波形蛋白、N-钙黏着蛋白表达水平明显增加, 而E-钙黏着蛋白表达明显降低,过表达Rab1A后显著逆转了miR-150-5p对EMT的影响。综上所述,miR-150-5p可以通过负向调控Rab1A抑制EMT,进而抑制乳腺癌细胞的侵袭和迁移。     

miR-17-5p promotes proliferation and epithelial-mesenchymal transition in human osteosarcoma cells by targeting SRC kinase signaling inhibitor 1

MicroRNA-17-5p (miR-17-5p) and epithelial-mesenchymal transition (EMT) have been reported to participate in the development and progression of multiple cancers. However, the relationship between the miR-17-5p and EMT in osteosarcoma (OS) is still poorly understood. This study was to investigate the effects of the miR-17-5p and its potential mechanism in regulating proliferation, apoptosis, and EMT of human OS. Quantitative real-time PCR was used to detect the miR-17-5p and SRC kinase signaling inhibitor 1 (SRCIN1) messenger RNA expression in OS specimens and cell lines. After transfection with miR-17-5p inhibitors, proliferation, apoptosis, migration, and invasion of OS cells were assessed by using the Cell Counting Kit-8, the annexin V-FITC apoptosis, wound-healing, and transwell assays. The SRCIN1 was validated as a target of the miR-17-5p through bioinformatics algorithms and luciferase reporter assay. Moreover, the expression of EMT markers, E-cadherin, N-cadherin, and Snail was identified by the Western blot analysis. MiR-17-5p was significantly upregulated in OS tumor samples and cell lines. It inhibited proliferation and EMT, and promoted apoptosis in OS. The SRCIN1 was identified as a direct target of the miR-17-5p. Silenced miR-17-5p could change the expression of EMT markers, such as upregulating the expression of E-cadherin, and downregulating the expression of N-cadherin and Snail through targeting the antioncogenic SRCIN1. These findings suggest that the miR-17-5p promotes cell proliferation, and EMT in human OS by directly targeting the SRCIN1, and reveal a branch of the miR-17-5p/SRCIN1/EMT signaling pathway involved in the progression of OS.     

Pleiotropic actions of miR-21 highlight the critical role of deregulated stromal microRNAs during colorectal cancer progression

The oncogene microRNA-21 (miRNA; miR-21) is overexpressed in most solid organ tumours; however, a recent examination of stage II colorectal cancer (CRC) specimens suggests this may be a stromal phenomenon and not only a feature of cancer cells. In vitro and in vivo studies show that miR-21 has potent pro-metastatic effects in various malignant carcinoma cell lines. The tumour microenvironment has also been identified as a key actor during the metastatic cascade; however to date the significance of deregulated miR-21 expression within the cancer-associated stroma has not been examined. In the present study, a quantitative RT-PCR-based analysis of laser microdissected tissue confirmed that miR-21 expression is associated with a four-fold mean increase in CRC stroma compared with normal tissue. In situ hybridisation using locked nucleic acid probes localised miR-21 expression predominantly to fibroblasts within tumour-associated stroma. To study the molecular and biological impact of deregulated stromal miR-21 in CRC, stable ectopic expression was induced in immortalised fibroblasts. This resulted in upregulated α-smooth muscle actin expression implying miR-21 overexpression is driving the fibroblast-to-myofibroblast transdifferentiation. Conditioned medium from miR-21-overexpressing fibroblasts protected CRC cells from oxaliplatin-induced apoptosis and increased their proliferative capacity. 3D organotypic co-cultures containing fibroblasts and CRC cells revealed that ectopic stromal miR-21 expression was associated with increased epithelial invasiveness. Reversion-inducing cysteine-rich protein with kazal motifs, an inhibitor of matrix-remodelling enzyme MMP2, was significantly downregulated by ectopic miR-21 in established and primary colorectal fibroblasts with a reciprocal rise in MMP2 activity. Inhibition of MMP2 abrogated the invasion-promoting effects of ectopic miR-21. This data, which characterises a novel pro-metastatic mechanism mediated by miR-21 in the CRC stroma, highlights the importance of miRNA deregulation within the tumour microenvironment and identifies a potential application for stromal miRNAs as biomarkers in cancer.     

MicroRNA对EMT的调节作用及其与肿瘤侵袭的关系

上皮间质转化（epithelial mesenchymal transition,EMT）是指上皮细胞表型由上皮向间质转换的生物学过程,可发生在生理过程中促进发育、组织愈合和修复。近年对肿瘤的研究发现,EMT与肿瘤的发生发展密切相关。肿瘤细胞发生EMT时,伴随着迁移、侵袭能力的增强,进而促进肿瘤的转移。EMT发生的程度以及相关标志分子的检测还可以用于判断肿瘤转移的危险和评估预后。MicroRNA(miRNA)作为非编码小RNA,通过与特定mRNA的3′UTR结合,在蛋白翻译水平抑制基因表达。本文主要综述目前发现的作用于EMT相关转录因子,如ZEB、SNAIL、TWIST的miRNA,以及在各种肿瘤中的表达情况和作用。其中,有些转录因子和miRNA之间,还存在相互抑制的复杂调节网络,因此,了解miRNA在肿瘤中对EMT的作用可能为肿瘤的治疗提供新的方法和策略。     

Growth arrest-specific 5 attenuates cisplatin-induced apoptosis in cervical cancer by regulating STAT3 signaling via miR-21

Cervical cancer is the most common cause of female cancer-related mortality worldwide. Decreased expression of long noncoding RNA growth arrest-specific 5 (GAS5) is found in human cervical cancer tissues and associated with poor prognosis. However, the studies on associations between GAS5 level and malignant phenotypes, as well as sensitivity to chemotherapeutic drug in cervical cancer cells are limited. In this study, overexpression of GAS5 in cervical cancer cells resulted in prohibited cell proliferation and colony formation, which were promoted by siGAS5. Enhanced GAS5 increased cell percentage in the G0/G1 phase and decreased cells percentage in the S phase, whereas reduced expression did not. The malignant behaviors of cervical cancer cells, manifested by cell migration and invasion, could be weakened by the GAS5 overexpression and enhanced by siGAS5. Furthermore, in cisplatin-induced cell, overexpression of GAS5 reduced cells viability and enhanced apoptosis, whereas in cells transfected with siGAS5, apoptosis eliminated. We have reported the upregulation of microRNA-21 (miR-21) and its oncogenetic roles in cervical cancer previously. In this study, we found the negative relationship between the GAS5 and miR-21. Moreover, the decrease of miR-21 associated proteins phosphorylated STAT3 and E2F3 was seen in GAS5 overexpressed cells, both of which could be increased by siGAS5. The GAS5 deficiency also reduced miR-21 target proteins TIMP3 and PDCD4 expressions. Taken together, the GAS5 expression level is inversely associated with malignancy, but positively associated with sensitivity to cisplatin-induced apoptosis, suggesting that GAS5 could be a biomarker of cisplatin-resistance in clinical therapy of human cervical cancer.     

LncRNA SNHG3 induces EMT and sorafenib resistance by modulating the miR-128/CD151 pathway in hepatocellular carcinoma

Dysregulation of long noncoding RNAs (lncRNAs) plays important roles in carcinogenesis and tumor progression, including hepatocellular carcinoma (HCC). Small nucleolar RNA host gene 3 (SNHG3) has been considered as an lncRNA to be associated with a poor prognosis in patients with HCC. Here, we reported that SNHG3 expression was significantly higher in the highly metastatic HCC (HCCLM3) cells compared with the lowly metastatic HCC cells (Hep3B and PLC/PRF/5). Furthermore, forced expression of SNHG3 promoted cell invasion, epithelial-mesenchymal transition (EMT), and sorafenib resistance in HCC. Moreover, SNHG3 overexpression induced HCC cells EMT via miR-128/CD151 cascade activation. Clinically, our data revealed that increased SNHG3 expression is correlated with poor HCC survival outcomes and sorafenib response. These data suggest that SNHG3 may be a novel therapeutic target and a biomarker for predicting response to sorafenib treatment of HCC.     

RSPO2 enhances cell invasion and migration via the WNT/β-catenin pathway in human gastric cancer

R-spondins comprise a group of secreted WNT agonists. R-spondin2 (RSPO2) plays a crucial role in the activation of the WNT/β-catenin pathway and oncogenesis, though its specific role in human gastric cancer (GC) remains unclear. In the current study, RSPO2 expression levels were upregulated in cancer specimens and cell lines (AGS and BGC-823). Inhibition of RSPO2 expression levels had distinct effects on cell invasion, migration, and epithelial-mesenchymal transition (EMT) in AGS and BGC-823 cells in vitro. Furthermore, RSPO2 positively correlated with leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), the receptor of RSPO2. Silencing RSPO2 reduced the expression of LGR5 and WNT/β-catenin effector molecule β-catenin together with downstream targets TCF-4 and Cyclin-D1. These observations demonstrate that upregulation of RSPO2 in GC specimens and cell lines is closely related to tumor invasion and migration and that RSPO2 promotes EMT in gastric cancer cells by activating WNT/β-catenin signaling.     

MicroRNA-424 regulates epithelial-mesenchymal transition of endometrial carcinoma by directly targeting insulin-like growth factor 1 receptor

Although numerous miRNAs are reported to contribute to the carcinogenesis of malignant tumor, the specific role of miR-424 in endometrial carcinoma is seldom reported. To explore the effect of miR-424 on epithelial-mesenchymal transition and its underlying mechanism, we detected miR-424 expression in endometrial carcinoma tissue and cells. We found that miR-424 was significantly downregulated in endometrial carcinoma tissues and cells, especially in HEC-1B cells. To perform the functional analysis, we transfected HEC-1B with miR-424-mi, miR-424-inh, mi-control, and inh-control, respectively. We found that overexpression of miR-424 significantly decreases cell proliferation and migration, accompanied with the increased E-cadherin/Vimentin expression and the transition of mesenchymal to epithelial cell phenotype. We identified that insulin-like growth factor-1 receptor (IGF-1R) was a potential target of miR-424 by computational analysis followed by luciferase reporter assays. Of note, we found that the downregulation of miR-424 in HEC-1B cells enhanced endogenous IGF-1R expression. Further mechanistic analysis revealed that forced expression of IGF-1R in miR-424-mim transfected cells remedied the weakened migration resulting from overexpression of IGF-1R. Taken together, the results of the current study demonstrated that miR-424 was a tumor suppressor for endometrial carcinoma and a favorable factor against tumor progression through targeting IGF-1R, thus providing a target for the treatment of endometrial carcinoma.