miR-30a通过靶向调控ZEB2抑制非小细胞肺癌的迁移与侵袭

目的:探讨miR-30a在非小细胞肺癌(non-small cell lung cancer,NSCLC)细胞中的表达情况及miR-30a在肺癌细胞迁移和侵袭过程中的作用及其机制.方法:采用qRT-PCR检测miR-30a在不同NSCLC细胞株中的表达情况;采用脂质体2000转染miR-30a mimics和E盒结合锌...     

血小板通过上调NF-κB信号通路增强乳腺癌循环肿瘤细胞的侵袭和迁移能力

目的:探讨血小板接触对乳腺癌循环肿瘤细胞（circulating tumor cells,CTCs）侵袭和迁移能力的影响。方法:利用CytoQuestTM CR抓取乳腺癌患者血液中的循环肿瘤细胞,通过RT-PCR检测Wnt2基因表达水平。通过Western blot检测肿瘤细胞上皮细胞-间充质转化（epithelial-mesenchymal transition,EMT）以及NF-κB信号通路相关蛋白的表达情况。通过细胞划痕、Transwell实验检测血小板的直接接触对肿瘤细胞侵袭和迁移能力的影响。通过封闭乳腺癌细胞中NF-κB的表达,观察NF-κB信号通路在肿瘤细胞侵袭和迁移能力中的重要作用。结果:RT-PCR结果显示,乳腺癌患者血液中的CTCs内Wnt2基因高表达。Western blot结果显示,血小板与乳腺癌细胞的直接接触增加了肿瘤细胞的上皮间质化进程,并诱导激活了肿瘤细胞的NF-κB通路。细胞划痕和Transwell实验结果显示,与血小板共培养可促进乳腺癌细胞的侵袭和迁移。此外,通过封闭乳腺癌细胞中NF-κB基因,可以降低Wnt2的表达,抑制肿瘤细胞的上皮间质化进程,减弱乳腺癌细胞的侵袭和迁移能力。结论:血小板与肿瘤细胞的直接接触促进了乳腺癌循环肿瘤细胞的侵袭和迁移能力,封闭NF-κB信号通路可能是抑制乳腺癌循环肿瘤细胞侵袭和迁移能力的有效策略。     

miR-21通过靶向PDCD4调控三阴性乳腺癌细胞的迁移和侵袭

目的： 研究miR-21在三阴性乳腺癌细胞MDA-MB-231中的表达,以及其是否通过调控PDCD4影响MDA-MB-231细胞的迁移和侵袭。方法： 采用实时定量PCR（qPCR）法检测MDA-MB-231细胞和正常乳腺细胞MCF-10A中miR-21和PDCD4 mRNA的表达。将MDA-MB-231细胞随机分为5组：空白对照组,转染miR-21模拟物组,模拟物对照组,转染miR-21抑制物组和抑制物对照组。采用Western blot法检测MDA-MB-231细胞PDCD4蛋白的表达;采用荧光素酶报告基因试剂盒检测转染不同载体后荧光强度的变化来判断miR-21的靶标;采用Transwell实验检测各组细胞的迁移和侵袭数目。结果： miR-21和PDCD4 mRNA在MDAMB-231细胞中的表达水平分别明显高于和低于MCF-10A细胞（P均 < 0.01）。过表达或抑制miR-21可调节PDCD4的表达水平。荧光素酶报告基因试剂盒检测结果显示miR-21可直接靶向调控PDCD4的表达。Transwell实验结果表明过表达miR-21表达能增强MDA-MB-231细胞的迁移和侵袭能力。结论： 在MDA-MB-231细胞中,miR-21通过靶向调控PDCD4表达影响细胞的迁移和侵袭。miR-21可能成为抑制三阴性乳腺癌迁移和侵袭的靶点。     

miR-21通过靶向PDCD4调控三阴性乳腺癌细胞的迁移和侵袭

目的： 研究miR-21在三阴性乳腺癌细胞MDA-MB-231中的表达，以及其是否通过调控PDCD4影响MDA-MB-231细胞的迁移和侵袭。方法： 采用实时定量PCR（qPCR）法检测MDA-MB-231细胞和正常乳腺细胞MCF-10A中miR-21和PDCD4 mRNA的表达。将MDA-MB-231细胞随机分为5组：空白对照组，转染miR-21模拟物组，模拟物对照组，转染miR-21抑制物组和抑制物对照组。采用Western blot法检测MDA-MB-231细胞PDCD4蛋白的表达；采用荧光素酶报告基因试剂盒检测转染不同载体后荧光强度的变化来判断miR-21的靶标；采用Transwell实验检测各组细胞的迁移和侵袭数目。结果： miR-21和PDCD4 mRNA在MDAMB-231细胞中的表达水平分别明显高于和低于MCF-10A细胞（P均 < 0.01）。过表达或抑制miR-21可调节PDCD4的表达水平。荧光素酶报告基因试剂盒检测结果显示miR-21可直接靶向调控PDCD4的表达。Transwell实验结果表明过表达miR-21表达能增强MDA-MB-231细胞的迁移和侵袭能力。结论： 在MDA-MB-231细胞中，miR-21通过靶向调控PDCD4表达影响细胞的迁移和侵袭。miR-21可能成为抑制三阴性乳腺癌迁移和侵袭的靶点。     

PP2药物抑制乳腺癌细胞侵袭与增殖的机制

目的以PP2E4-Amino-5-（4-Chloro-Phenyl）-7-（t-Butyl）PyrazoloE3,4-d]Pyrimidine]药物（src激酶抑制剂）处理乳腺癌细胞,检测src激酶及E-cadherin蛋白表达水平的变化,观察PP2对乳腺癌细胞增殖和侵袭能力的影响,并探讨其可能的机制。方法PP2处理乳腺癌细胞MDA-MB231,Westernblot检测src及其相关蛋白的表达;Boyden小室实验检测细胞侵袭能力;MTT检测细胞的增殖能力。结果PP2处理MDA-MD231细胞后,src表达水平明显降低,Ecadherin表达水平升高;细胞的增殖和侵袭能力均受到明显抑制,剂量越高抑制作用越明显（P〈0．05）。结论PP2通过提高细胞粘附分子E-cadherin的表达,从而抑制乳腺癌细胞MDAMB-231的增殖和侵袭能力。     

miR-653调控靶基因在乳腺癌发生及发展中的作用

目的:分析miR-653在乳腺癌细胞及肿瘤组织中的表达变化,研究其对乳腺癌细胞生物学行为的影响,揭示其在乳腺癌中发挥的作用及其相关作用机制。方法:采用qRT-PCR比较miR-653在正常组织、细胞和乳腺癌组织、乳腺癌细胞系中的表达水平;采用CCK8法和Tranwell检测miR-653对细胞的增殖、迁移能力的影响;采用qRT-PCR和Western blot检测NFKBIB在正常组织、细胞和乳腺癌组织、乳腺癌细胞系中的表达水平;采用CCK8法、流式细胞法和Tranwell检测miR-653和NFKBIB对乳腺癌细胞增殖、细胞周期、迁移能力的影响;Western blot检测miR-653对NFKBIB、p65、Livin和Survivin蛋白表达的影响。结果:发现miR-653在乳腺癌肿瘤组织和乳腺癌细胞株中表达明显升高,可以促进乳腺癌细胞的增殖、迁移能力;NFKBIB是miR-653的靶基因,miR-653可以负性调控NFKBIB的mRNA和蛋白表达;转染miR-653可以促进细胞的增殖、迁移能力以及诱导S期阻滞,过表达NFKBIB可以逆转这种促进效果;miR-653可以通过调控NFKBIB激活NF-κB通路调节其下游蛋白Livin和Survivin的表达。结论:本研究揭示了miR-653通过抑制靶基因NFKBIB的表达激活NF-κB,促进乳腺癌细胞的增殖、迁移以及诱导S期阻滞,在乳腺癌中发挥促癌因子的作用。因此miR-653具有成为乳腺癌诊断及治疗新靶点的潜力。     

circNEIL3 通过靶向miR-4784 调控乳腺癌MDA-MB-231 细胞的增殖、迁移和侵袭

目的：研究环状RNA nei 样DNA糖化酶3（circNEIL3）和微小RNA（miR）-4784 对乳腺癌细胞MDA-MB-231 的增殖、迁移和侵袭的影响。方法：收集2018 年1月至2019 年12月在济南市中西医结合医院经组织病理诊断为乳腺癌并行手术切除的45 例乳腺癌患者的癌组织和配对癌旁组织,qPCR 法检测乳腺癌组织、癌旁组织中circNEIL3 和miR-4784 的相对水平。将circNEIL3 的小干扰RNA（si-circNEIL3）、miR-4784 模拟物、si-circNEIL3+miR-4784 抑制物分别转染MDA-MB-231 细胞,采用CCK-8法、平板克隆实验、划痕愈合实验、Transwell 实验检测circNEIL3和miR-4784 表达对细胞活力、克隆形成、迁移和侵袭的影响。双荧光素酶报告基因实验、RNA免疫沉淀（RIP）和RNA pull-down 实验检测circNEIL3和miR-4784 之间相互作用。结果：乳腺癌组织中circNEIL3呈高表达（P<0.05）,miR-4784 呈低表达（P<0.05）。干扰circNEIL3显著降低MDA-MB-231 细胞活力、克隆形成数、划痕愈合率以及侵袭数（均P<0.05）。过表达miR-4784 显著降低MDA-MB-231 细胞活力、克隆形成数、划痕愈合率以及侵袭数（均P<0.05）。双荧光素酶报告基因实验、RIP 和 RNA pull-down 实验均证实circNEIL3 与miR-4784 可直接结合,干扰circNEIL3 能明显上调miR-4784表达（P<0.05）,过表达circNEIL3 能明显下调 miR-4784 表达（P<0.05）。抑制miR-4784 表达部分逆转干扰circNEIL3对MDA-MB-231 细胞活力、克隆形成、迁移和侵袭的抑制作用（P<0.05）。结论：干扰circNEIL3通过靶向上调miR-4784表达抑制MDA-MB-231细胞的增殖、迁移和侵袭。     

环氧木香内酯通过NF-κB信号通路下调MMP-2/9抑制胶质瘤细胞U251侵袭和迁移

目的探讨环氧木香内酯(EMCL)对胶质瘤U251细胞侵袭和迁移的抑制作用及其机制。方法不同浓度EMCL处理胶质瘤U251细胞48 h后,用CCK-8法检测EMCL对胶质瘤细胞增殖抑制作用及半数抑制浓度IC₅₀;采用划痕实验和Transwell侵袭实验检测EMCL对胶质瘤U251细胞侵袭迁移的影响;采用Western blot检测胶质瘤细胞中MMP-2、MMP-9、p-p65和p65蛋白的表达。结果胶质瘤U251细胞经EMCL处理后,细胞数目显著减少,细胞形态变圆、变小,细胞与细胞间的接触、丝状伪足均显著减少;胶质瘤U251细胞迁移和侵袭能力随着EMCL浓度的升高而显著下降;MMP-2和MMP-9蛋白表达均下调;p-p65/p65的表达下调。结论环氧木香内酯能够抑制胶质瘤U251细胞侵袭和迁移能力。     

Radiation-enhancement of MDA-MB-231 breast cancer cell invasion prevented by a cyclooxygenase-2 inhibitor

Background:

Recent evidences support that radiation can promote the invasion of cancer cells. As interactions between cancer cells and surrounding stromal cells can have an important role in tumour progression, we determined whether an irradiation to fibroblasts can enhance the invasiveness of breast cancer cells. The role of cyclooxygenase-2 (COX-2), an inflammatory enzyme frequently induced by radiotherapy, was investigated.

Methods:

Irradiated 3T3 fibroblasts were plated in the lower compartment of invasion chambers and used as chemoattractant for non-irradiated human breast cancer cell MDA-MB-231, which are oestrogen receptor negative (ER(−)) and the oestrogen receptor positive (ER(+)) MCF-7 cells. Stimulation of COX-2 expression in irradiated 3T3 cells was measured by a semi-quantitative qPCR and western blot. Capacity of the major product of COX-2, the prostaglandin E2 (PGE₂), to stimulate the production of the matrix metalloproteinase-2 (MMP-2) and cancer cell invasion were assessed with a zymography gel and invasion chambers.

Results:

Irradiation (5 Gy) of 3T3 fibroblasts increased COX-2 expression and enhanced by 5.8-fold the invasiveness of non-irradiated MDA-MB-231 cells, while their migration was not modified. Addition of the COX-2 inhibitor NS-398 completely prevented radiation-enhancement of cancer cell invasion. Further supporting the potential role of COX-2, addition of PGE₂ has increased cancer cell invasion and release of MMP-2 from the MDA-MB-231 cells. This effect of radiation was dependant on the expression of membrane type 1 (MT1)–MMP, which is required to activate the MMP-2, but was not associated with the ER status. Although irradiated fibroblasts stimulated the invasiveness of MDA-MB-231 ER(−) cells, no enhancement was measured with the ER(+) cell line MCF-7.

Conclusions:

Radiation-enhancement of breast cancer cell invasion induced by irradiated 3T3 fibroblasts is not dependant on the ER status, but rather the expression of MT1–MMP. This adverse effect of radiation can be prevented by a specific COX-2 inhibitor.     

MiR-422a weakened breast cancer stem cells properties by targeting PLP2

Objective: This study investigated miR-422a and PLP2 expressions in breast cancer cells and breast cancer stem cells (BCSCs). Besides, their influences on polymorphism changes were observed.

Methods: Flow cytometry and fluorescence-activated cell sorting was performed and CD24^?/CD44⁺ cells were sorted from breast cancer cells and recognized as BCSCs. Microarray was applied to search for the differentially expressed miRNAs and mRNAs between MCF7 and BCSCs. The aberrant expression of miR-422a and PLP2 was further confirmed by RT-qPCR and the direct targeted relationship was verified by dual-luciferase reporter assay. After in vitro transfection, the expression of miR-422a and PLP2 were manipulated and biological functions of BMSCs were compared with CCK-8, colony formation and sphere formation assay. The tumorigenesis ability of transfected BMSCs was also investigated in NOD/SCID tumor mice models.

Results: BMSCs were successfully established from MCF7 cells and miR-422a expression was downregulated while PLP2 level decreased in BMSCs. MiR-422a directly targets the 3′UTR of PLP2 and suppressed its expression. Besides, the up-regulation of miR-422a contributed to weakened ability of proliferation and microsphere formation of BMSCs, while PLP2 overexpression facilitated those biological abilities. Tumorigenesis of BMSCs in mice models was impaired by either overexpression of miR-442a or silencing of PLP2.

Conclusion: Up-regulation of miR-422a attenuated microsphere formation, proliferation and tumor formation of breast cancer stem cells via suppressing the PLP2 expression.     

miR-340 inhibition of breast cancer cell migration and invasion through targeting of oncoprotein c-Met

BACKGROUND:

Different microRNAs have been shown to have oncogenic and tumor‐suppressive functions in human cancers. Detection of their expression may lead to identifying novel markers for breast cancer.

METHODS:

The authors detected miR‐340 expression in 4 human breast cell lines and then focused on its role in regulation of tumor cell growth, migration, and invasion and target gene expression. They then analyzed miR‐340 expression in benign and cancerous breast tissue specimens.

RESULTS:

Endogenous miR‐340 expression was down‐regulated in the more aggressive breast cancer cell lines, which was confirmed in breast cancer tissue specimens by using quantitative real‐time polymerase chain reaction. Further studies showed that induction of miR‐340 expression was able to suppress tumor cell migration and invasion, whereas knockdown of miR‐340 expression induced breast cancer cell migration and invasion. At the gene level, the authors identified c‐Met as a direct miR‐340 target to mediate cell migration and invasion through regulation of MMP‐2 and MMP‐9 expression. Ex vivo, loss of miR‐340 expression was associated with lymph node metastasis, high tumor histological grade, clinical stage, and shorter overall survival of breast cancer as well as increased c‐Met expression in breast cancer tissue specimens.

CONCLUSIONS:

miR‐340 may play an important role in breast cancer progression, suggesting that miR‐340 should be further evaluated as a novel biomarker for breast cancer metastasis and prognosis, and potentially a therapeutic target. Cancer 2011. © 2011 American Cancer Society.     

Lipocalin 2 promotes inflammatory breast cancer tumorigenesis and skin invasion

Inflammatory breast cancer (IBC) is an aggressive form of primary breast cancer characterized by rapid onset and high risk of metastasis and poor clinical outcomes. The biological basis for the aggressiveness of IBC is still not well understood and no IBC‐specific targeted therapies exist. In this study, we report that lipocalin 2 (LCN2), a small secreted glycoprotein belonging to the lipocalin superfamily, is expressed at significantly higher levels in IBC vs non‐IBC tumors, independently of molecular subtype. LCN2 levels were also significantly higher in IBC cell lines and in their culture media than in non‐IBC cell lines. High expression was associated with poor‐prognosis features and shorter overall survival in IBC patients. Depletion of LCN2 in IBC cell lines reduced colony formation, migration, and cancer stem cell populations in vitro and inhibited tumor growth, skin invasion, and brain metastasis in mouse models of IBC. Analysis of our proteomics data showed reduced expression of proteins involved in cell cycle and DNA repair in LCN2‐silenced IBC cells. Our findings support that LCN2 promotes IBC tumor aggressiveness and offer a new potential therapeutic target for IBC.