Collective cell migration of the nephric duct requires FGF signaling

Background : During the course of development, the vertebrate nephric duct (ND) extends and migrates from the place of its initial formation, adjacent to the anterior somites, until it inserts into the bladder or cloaca in the posterior region of the embryo. The molecular mechanisms that guide ND migration are poorly understood. Results : A novel Gata3‐enhancer‐Gfp‐based chick embryo live imaging system was developed that permits documentation of ND migration at the individual cell level for the first time. FGF Receptors and FGF response genes are expressed in the ND, and FGF ligands are expressed in surrounding tissues. FGF receptor inhibition blocked nephric duct migration. Individual inhibitors of the Erk, p38, or Jnk pathways did not affect duct migration, but inhibition of all three pathways together did inhibit migration of the duct. A localized source of FGF8 placed adjacent to the nephric duct did not affect the duct migration path. Conclusions : FGF signaling acts as a “motor” that is required for duct migration, but other signals are needed to determine the directionality of the duct migration pathway. Developmental Dynamics 244:157–167, 2015. © 2014 Wiley Periodicals, Inc.     

miR-98对肝癌 HepG2细胞增殖、凋亡以及侵袭、迁移能力的影响

目的：研究 miR-98对肝癌 HepG2细胞增殖、凋亡和侵袭、迁移能力的影响及其可能机制。方法将 miR-98mimics、mimics-NC、miR-98inhibitor、inhibitor-NC 瞬时转入肝癌 HepG2细胞内,应用噻唑盐( MTT)法、流式细胞仪、Tr-answell 小室实验检测 miR-98对肝癌 HepG2细胞增殖、凋亡以及侵袭、迁移能力的影响,进一步用 Western blot 法检测各组 Bcl-2蛋白的表达水平。结果 MTT 实验表明 miR-98过表达后,肝癌细胞的增殖能力明显低于对照组;Annexin V-FITC / PI 凋亡实验证实上调 miR-98表达后,细胞的凋亡率较对照组升高;Transwell 小室实验表明上调 miR-98可使肝癌细胞的侵袭、迁移能力减弱。而当 miR-98被抑制后,肝癌HepG2细胞的增殖及侵袭、迁移能力则明显增强,凋亡率则下降。 Western blot 实验检测发现 miR-98过表达后,Bcl-2的表达降低。结论 miR-98可能在肝癌的发生、发展中发挥着抑癌基因的作用;miR-98可能通过下调 Bcl-2的表达,促进肝癌 HepG2细胞凋亡。     

Reelin receptors ApoER2 and VLDLR are expressed in distinct spatiotemporal patterns in developing mouse cerebral cortex

In mammalian developing brain, neuronal migration is regulated by a variety of signaling cascades, including Reelin signaling. Reelin is a glycoprotein that is mainly secreted by Cajal–Retzius neurons in the marginal zone, playing essential roles in the formation of the layered neocortex via its receptors, apolipoprotein E receptor 2 (ApoER2) and very low density lipoprotein receptor (VLDLR). However, the precise mechanisms by which Reelin signaling controls the neuronal migration process remain unclear. To gain insight into how Reelin signaling controls individual migrating neurons, we generated monoclonal antibodies against ApoER2 and VLDLR and examined the localization of Reelin receptors in the developing mouse cerebral cortex. Immunohistochemical analyses revealed that VLDLR is localized to the distal portion of leading processes in the marginal zone (MZ), whereas ApoER2 is mainly localized to neuronal processes and the cell membranes of multipolar cells in the multipolar cell accumulation zone (MAZ). These different expression patterns may contribute to the distinct actions of Reelin on migrating neurons during both the early and late migratory stages in the developing cerebral cortex. J. Comp. Neurol. 523:463–478, 2015. © 2014 Wiley Periodicals, Inc.     

趋化因子CCL22对肺癌细胞迁移和侵袭的影响

目的观察趋化因子CCL22对肺癌SBC-5细胞迁移和侵袭能力的影响。方法取肺癌细胞系SBC-5细胞,RPMI-1640培养基培养,5%CO2培养箱孵育,清洗消化后传代培养。予100ng/m L的CCL22诱导肺癌SBC-5细胞,设Control组、CCL22组(100ng/m L)、MIX组(CCL22 100ng/m L+蛋白激酶抑制剂U0126 10μmol),观察细胞迁移及侵袭能力的变化;加入蛋白激酶抑制剂(U0126)后细胞迁移及侵袭能力的变化。结果 CCL22诱导肺癌SBC-5细胞后,CCL22组细胞迁移距离(351.9±16.4)μm,明显大于Control组的(112.6±27.2)μm和MIX组的(145.1±29.6)μm(P0.05),MIX组和Control组比较差异无统计学意义(P0.05)。CCL22组平均侵袭细胞数(505.5±66.3)个,显著高于Control组的(199.2±32.8)个和MIX组的(95.7±19.1)个(P0.05),MIX组明显低于Control组(P0.05)。结论趋化因子CCL22可在体外诱导肺癌SBC-5细胞迁移和侵袭,而蛋白激酶抑制剂(U0126)可抑制CCL22诱导肺癌细胞的迁移及侵袭。     

微小RNA-320a通过靶向FoxM1调控肝癌细胞迁移

目的：探讨微小RNA-320a (miR-320a)在肝癌细胞中对癌基因FoxM1的靶向调控作用以及对肝癌细胞迁移能力的影响,为肝癌治疗提供新的靶点。方法通过信息学工具网站http：//www.microRNA.org找到可能靶向调控FoxM1表达的微小RNA;利用蛋白印记和双荧光素酶报告基因试验验证miR-320a对FoxM1的调控作用;采用Transwell小室分析miR-320a和FoxM1对肝癌细胞迁移的影响。结果信息学分析表明,miR-320a在FoxM1的3'端非翻译区存在2个潜在结合位点。蛋白印迹实验显示miR-320a降低FoxM1在肝癌细胞中的蛋白水平,双荧光素酶报告基因试验显示miR-320a可以调控FoxM1表达。miR-320a类似物对FoxM1表达有下调作用（P<0.01）,miR-320a抑制物对FoxM1表达有上调作用（P<0.05）。Transwell试验表明miR-320a类似物可抑制肝癌细胞株Huh7、HCC-LM3的迁移能力,miR-320a抑制物可增加Huh7、HCC-LM3的迁移能力。当使用小干扰RNA下调FoxM1在这些细胞株中的表达后,miR-320a类似物和miR-320a抑制物对肝癌细胞迁移能力的调控作用明显减弱。结论 miR-320a有抑制肝癌细胞迁移的作用,这种抑制作用是通过靶向调控癌基因FoxM1来实现的。     

抑制GM130表达对胃癌细胞增殖、侵袭及迁移能力的影响

目的 分析GM130在不同分化人胃癌细胞系的差异表达,利用小干扰RNA技术来沉默GM130基因,研究其对胃癌细胞生物学行为的影响.方法 体外培养3株不同分化程度胃癌细胞系(高分化MKN-28、中分化SGC-7901、低分化MKN-45),Western blot和RT-PCR筛选出高表达的GM130细胞株MKN-45、SGC-7901,设计并化学合成、转染、筛选出针对GM130的小干扰RNA片段.通过MTF、Transwell、Matrigel侵袭实验,观测下调GM130后对胃癌细胞株的生物学行为影响,Western blot检测细胞中MMP-2、MMP-9蛋白的变化.结果 Western blot和RT-PCR检测结果显示,在MKN-45、SGC-7901细胞中GM130蛋白和mRNA水平呈现高表达水平.Westem blot和qRT-PCR结果显示在低分化胃癌MKN-45细胞中,GM130-siRNA-519转染组GM130基因的表达水平显著抑制(P＜0.05).与对照组相比,抑制转染组细胞的增殖、迁移能力明显下降,穿膜细胞数明显减少,MMP-2、MMP-9的蛋白表达水平显著降低(P＜0.05).结论 抑制GM130基因的表达下调可显著降低胃癌细胞的增殖和体外侵袭转移能力.     

MicroRNA-200a inhibits epithelial-mesenchymal transition in human hepatocellular carcinoma cell line

Objective: Our study investigated the role of microRNA (miR)-200a and its molecular targets in hepatocellular carcinoma (HCC) cells. Methods: An inhibitor of miR-200a was transiently transfected into the hepatocellular carcinoma cell line, MHCC-97L. The effect of this transfection on mRNA levels of epithelial-mesenchymal transition (EMT)-related genes was measured by fluorescence-based quantitative real-time polymerase chain reaction (qRT-PCR). Further, protein levels of EMT-related genes, cell proliferation and apoptosis-related markers were assessed by Western blot analysis in these transfected cells. MTT and wound-healing assay were used to evaluate the proliferation and migration of MHCC-97L cells in presence and in absence of miR-200a inhibitor. Results: Compared with miR-NC control group, qRT-PCR results in anti-miR-200a group revealed a significant reduction in the mRNA levels of E-cadherin, with a concomitant increasing in vimentin mRNA level (all P < 0.05). Western blot results showed higher E-cadherin and Caspase-3 protein expressions in anti-miR-200a group compared to miR-NC group (P < 0.05). In addition, vimentin and Ki-67 protein expression was found sharply decreased in anti-miR-200a group compared to miR-NC group (P < 0.05). Consistent with this, wound-healing and MTT assay showed that migration and proliferation capacity of MHCC-97L cells in anti-miR-200a group is significantly increased compared with miR-NC group (both P < 0.05). Conclusion: Our study reveals an important role of miR-200a in inhibiting EMT, proliferation and migration in HCC cells, suggesting the possibility of miR-200a-based therapeutics in HCC.     

TRAF4 enhances oral squamous cell carcinoma cell growth,invasion and migration by Wnt-β-catenin signaling pathway

Oral squamous cell carcinoma (OSCC) ranks as the fifth most common cancer worldwide with poor prognosis. Recently, tumor necrosis factor receptor-associated factor 4 (TRAF4) has attracted increasing attenuation due to its overexpression in certain cancers. However, its function and underlying mechanism in OSCC remains elusive. In this study, the high expression of TRAF4 mRNA and protein levels was noted in OSCC cell lines. Its overexpression with pcDNA3.1-TRAF4 vector transfection dramatically promoted cell proliferation and inhibited cell apoptosis, indicating a pivotal role of TRAF4 in OSCC cell growth. Simultaneously, TRAF4 elevation also increased cell invasion and migration. Mechanism analysis confirmed that TRAF4 up-regulation induced the expression of β-catenin and the downstream target molecules of cyclinD1, c-myc, Bcl-2, MMP-9 and MMP-2, indicating that TRAF4 could induce the activation of Wnt/β-catenin pathway. After pretreatment with β-catenin siRNA, the pathway was remarkably silenced. Simultaneously, cell growth, invasion and migration induced by TRAF4 were strikingly abrogated, suggesting that TRAF4 may promote OSCC cell growth, invasion and migration by Wnt/β-catenin pathway. Together, this study confirmed that TRAF4 acts as an oncogene for the development and progression of OSCC. Therefore, our study may support a promising therapeutic target for the treatment of OSCC.     

HOXA10 controls proliferation,migration and invasion in oral squamous cell carcinoma

Although HOX genes are best known for acting in the regulation of important events during embryogenesis, including proliferation, differentiation and migration, alterations in their expression patterns have been frequently described in cancers. In previous studies we analyzed the expression profile of the members of the HOX family of homeobox genes in oral samples of normal mucosa and squamous cell carcinoma (OSCC) and identified differently expressed genes such as HOXA10. The present study aimed to validate the increased expression of HOXA10 in OSCCs, and to investigate the effects arising from its knockdown in OSCC cells. The levels of HOXA10 mRNA were determined in human OSCC samples and cell lines by quantitative PCR, and HOXA10-mediated effects on proliferation, apoptosis, adhesion, epithelial-mesenchymal transition (EMT), migration and invasion were studied in HSC-3 tongue carcinoma cells by using retrovirus-mediated RNA interference. Higher expression of HOXA10 mRNA was observed in OSCC cell lines and in tumor tissues compared to normal controls. HOXA10 knockdown significantly reduced the proliferation of the tumor cells which was accompanied by increased levels of p21. HOXA10 silencing also significantly induced the expression of EMT markers and enhanced the adhesion, migration and invasion of HSC-3 cells. No effects on cell death were observed after HOXA10 knockdown. The results of the current study confirm the overexpression of HOXA10 in OSCCs, and further demonstrate that its expression is functionally associated with several important biological processes related to oral tumorigenesis, such as proliferation, migration and invasion.