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1.
Recent studies have suggested that inhibitors of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (statins) can play a role in protection against vascular risk, which is independent of cholesterol reduction. It could act by inhibiting the synthesis of isoprenoids (farnesylpyrophosphate (FPP) and geranylgeranylpyrophosphate (GGPP)), which are respectively essential for membrane attachment and biological activity of GTPases Ras and RhoA. This study demonstrates that a statin (cerivastatin) inhibits angiogenesis. This effect was due to a decrease in endothelial cell locomotion which was reversed by GGPP. It was mainly related to delocalization of RhoA from cell membrane to cytoplasm, responsible for the disorganization of actin stress fibers. Furthermore, a decrease in MMP-2 secretion, involved in cell invasion, was also observed. This effect is rather due to Ras inhibition as it was reversed by FPP. This anti-angiogenic activity could explain the beneficial effect of statins on atherosclerosis and on cancer prevention as shown by clinical studies.  相似文献   

2.
Odontogenic ameloblast‐associated protein (ODAM) contributes to cell adhesion. In human cancer, ODAM is down‐regulated, and the overexpression of ODAM results in a favourable prognosis; however, the molecular mechanisms underlying ODAM‐mediated inhibition of cancer invasion and metastasis remain unclear. Here, we identify a critical role for ODAM in inducing cancer cell adhesion. ODAM induced RhoA activity and the expression of downstream factors, including Rho‐associated kinase (ROCK). ODAM‐mediated RhoA signalling resulted in actin filament rearrangement by activating PTEN and inhibiting the phosphorylation of AKT. When ODAM is overexpressed in MCF7 breast cancer cells and AGS gastric cancer cells that activate RhoA at high levels, it decreases motility, increases adhesion and inhibits the metastasis of MCF7 cells. Conversely, depletion of ODAM in cancer cells inhibits Rho GTPase activation, resulting in increased cancer migration and invasion. These results suggest that ODAM expression in cells maintains their adhesion, resulting in the prevention of their metastasis via the regulation of RhoA signalling in breast cancer cells. Copyright © 2015 John Wiley & Sons, Ltd. SIGNIFICANCE Breast cancer represents the first most frequent cancer, and the ratio of mortality is high in women. Of utmost importance for reducing risk by breast cancer are their anti‐invasion mechanisms, particularly in the non‐invasive cancer cells because metastasis is the principal cause of death among cancer patients. ODAM induced RhoA activity. ODAM‐mediated RhoA signalling resulted in actin filament rearrangement, increased cell adhesion and inhibited the migration/invasion of MCF7 cells. These results suggest that ODAM expression maintains their adhesion, resulting in the prevention of their metastasis via the regulation of RhoA signalling in breast cancer cells.  相似文献   

3.
目的:明确FAP是否通过RhoA/ROCK、Racl-GTP通路发挥促增殖、侵袭和迁移作用。方法:用MTT实验,Transwell实验和迁移实验检测FAP、RhoA/ROCK、Racl-GTP对卵巢癌细胞系HO-8910PM的增殖,侵袭和迁移的影响。结果:1、MTT法,迁移和侵袭实验证实用Y-27632抑制RhoA/ROCK途径能够促进卵巢癌细胞的增殖、迁移和侵袭,与FAP联合作用时促进作用增强。2、MTT法,迁移和侵袭实验证实NSC23766抑制Racl途径能够抑制卵巢癌细胞的增殖、迁移和侵袭,与FAP联合作用使FAP的促进作用减弱。结论:l、RhoA/ROCK通路抑制HO一8910PM细胞增殖、迁移和侵袭;Racl-GTP促进H0—8910PM细胞增殖、迁移和侵袭。2、FAP不是通过RhoA/ROCK而是通过Racl—GTP信号通路在HO.8910PM细胞发挥促增殖、迁移和侵袭作用的。  相似文献   

4.
目的:明确FAP 是否通过RhoA/ROCK、Rac1-GTP 通路发挥促增殖、侵袭和迁移作用。方法:用MTT 实验,Transwell 实验 和迁移实验检测FAP、RhoA/ROCK、Rac1-GTP 对卵巢癌细胞系HO-8910PM 的增殖,侵袭和迁移的影响。结果:1、MTT 法,迁移和 侵袭实验证实用Y-27632 抑制RhoA/ROCK 途径能够促进卵巢癌细胞的增殖、迁移和侵袭,与FAP 联合作用时促进作用增强。 2、MTT 法, 迁移和侵袭实验证实NSC23766 抑制Rac1 途径能够抑制卵巢癌细胞的增殖、迁移和侵袭,与FAP 联合作用使FAP 的 促进作用减弱。结论:1、RhoA/ROCK 通路抑制HO-8910PM 细胞增殖、迁移和侵袭;Rac1-GTP 促进HO-8910PM 细胞增殖、迁移 和侵袭。2、FAP不是通过RhoA/ROCK而是通过Rac1-GTP 信号通路在HO-8910PM细胞发挥促增殖、迁移和侵袭作用的。  相似文献   

5.
Angiogenesis is critical for tumour growth and metastasis where factors that regulate this process are potential targets for development of anti-cancer drugs. In this study, we show that the first TSR domain of the extracellular matrix protease ADAMTS5, unlike the second TSR, has anti-angiogenic activities where it inhibits endothelial cell tube formation on Matrigel, reduces cell proliferation and attachment, while promoting cell apoptosis and migration, all in a dose-dependent manner. Furthermore, it influences the architecture of endothelial cells by disrupting actin stress fibres and reducing focal adhesions, likely via suppressing RhoA activation. TSR1 of ADAMTS5 is therefore a novel anti-angiogenic peptide and could serve as a prototype for future development into anti-cancer drugs.  相似文献   

6.
Triple-negative breast cancer (TNBC) is defined as a group of primary breast cancers lacking expression of estrogen, progesterone, and human epidermal growth factor receptor-2 (HER-2) receptors, characterized by higher relapse rate and lower survival compared with other subtypes. Due to lack of identified targets and molecular heterogeneity, conventional chemotherapy is the only available option for treatment of TNBC, but non-discordant positive therapeutic efficacy could not be achieved. Here, we demonstrated that these TNBC cells were sensitive to teriflunomide, which was a well-known immunomodulatory drug for treatment of relapsing multiple sclerosis (MS). Potent anti-cancer effects in TNBC in vitro, including proliferation inhibition, cell cycle delay, cell apoptosis, and suppression of cell motility and invasiveness, could be achieved with this agent. Of note, we showed that multiple signals involved in TNBC proliferation, survival, migratory, and invasive potential were under regulation by teriflunomide. Among them, we identified down-regulation of growth factor receptors to abolish growth maintenance, suppression of c-Myc, and cyclin D1 to contribute to its anti-proliferative effect, modulation of components of cell cycle to induce S-phase arrest, degradation of Bcl-xL, and up-regulation of BAX via activation of MAPK pathway to induce apoptosis, and inhibition of epithelial-mesenchymal transition (EMT) process, matrix metalloproteinase-9 (MMP9) expression, and inactivation of Src/FAK to reduce TNBC migration and invasion. The results identified teriflunomide may be of therapeutic benefit for the more aggressive and difficult-to-treat breast cancer subtype, indicating the use of teriflunomide for clinical trials for treatment of TNBC patients.  相似文献   

7.
Long non‐coding RNA (lncRNA) H19 in tumors played important roles in various biological processes. However, the biological role and molecular mechanism of H19 in breast cancer are unclear. Here, we found that H19 was aberrantly upregulated in human breast tumor tissues and cells. A negative correlation between H19 and miR‐152 and positive correlation between H19 and DNMT1 mRNA were observed. Downregulation of H19 and DNMT1 significantly retarded breast cancer cell proliferation and invasion. H19 act as an endogenous sponge by directly binding to miR‐152. miR‐152 directly targeted DNMT1 and was regulated by H19. Besides, H19 overexpression dramatically relieved the inhibition of miR‐152 on DNMT1 expression. miR‐152 inhibition and DNMT1 overexpression obviously reversed the inhibitory effects of H19 downregulation on cell proliferation and invasion. In conclusion, H19 promoted proliferation and invasion of breast cancer through the miR‐152/DNMT1 axis, providing a novel mechanism about the occurrence and development of breast cancer.  相似文献   

8.
Fascin, an actin-cross-linking protein, is up-regulated in breast cancer and correlates with a more aggressive disease. This study was conducted to elucidate the effects of manipulating fascin in breast cancer cells on the metastasis-associated events, including proliferation, adhesion, invasion, epithelial-mesenchymal transition (EMT) and enrichment of a CD44(+) /CD24(-) subpopulation that show some stem/progenitor cell properties. Western blot analysis of a panel of breast cancer cell lines revealed high expression of fascin in MDA-MB-435 and MDA-MB-231 cells but revealed no or low expression in MDA-MB-453, Her-18 and T47D. Gain-of-function and loss-of-function studies in breast cancer cells demonstrated that forced expression of fascin promoted cell proliferation assessed by the MTT assay, decreased cellular adhesion to fibronectin and potentiated the invasive capacity in the Transwell chamber invasion assay. Conversely, down-regulation of fascin via small interfering RNA increased cell adhesion and facilitated cell proliferation and invasion. In addition, fascin participated in the EMT and modulated the proportion of the CD44(+) /CD24(-) subpopulation in breast cancer cells. In conclusion, our data highlight an important role for fascin in breast cancer progression in vitro through orchestrating a variety of cellular events associated with metastasis, and thus, targeting this gene might have therapeutic implications.  相似文献   

9.
Zheng S  Huang J  Zhou K  Zhang C  Xiang Q  Tan Z  Wang T  Fu X 《PloS one》2011,6(7):e22439
Estrogen promotes breast cancer metastasis. However, the detailed mechanism remains largely unknown. The actin binding protein ezrin is a key component in tumor metastasis and its over-expression is positively correlated to the poor outcome of breast cancer. In this study, we investigate the effects of 17β-estradiol (E2) on the activation of ezrin and its role in estrogen-dependent breast cancer cell movement. In T47-D breast cancer cells, E2 rapidly enhances ezrin phosphorylation at Thr(567) in a time- and concentration-dependent manner. The signalling cascade implicated in this action involves estrogen receptor (ER) interaction with the non-receptor tyrosine kinase c-Src, which activates the phosphatidylinositol-3 kinase/Akt pathway and the small GTPase RhoA/Rho-associated kinase (ROCK-2) complex. E2 enhances the horizontal cell migration and invasion of T47-D breast cancer cells in three-dimensional matrices, which is reversed by transfection of cells with specific ezrin siRNAs. In conclusion, E2 promotes breast cancer cell movement and invasion by the activation of ezrin. These results provide novel insights into the effects of estrogen on breast cancer progression and highlight potential targets to treat endocrine-sensitive breast cancers.  相似文献   

10.
Inactivation of PI 3-kinase (PI3K) signalling is critical for tumour suppression by PTEN. This is thought to be a unidirectional relationship in which PTEN degrades the lipids produced by PI3K, thus controlling cell proliferation, survival and migration. We now show that this relationship is in fact bidirectional, whereby PI3K reciprocally controls PTEN. We report that the p110delta PI3K negatively regulates PTEN, through a pathway involving inhibition of RhoA. Inactivation of p110delta in macrophages led to reduced Akt and Rac1 activation, but paradoxically to increased RhoA and PTEN activity. Partial inactivation of p190RhoGAP and a reduced binding of cytoplasmic RhoA to the cyclin-dependent kinase inhibitor p27 both contributed to the increased RhoA-GTP levels upon p110delta inactivation. Pharmacological inhibition of ROCK, a downstream effector kinase of RhoA, restored all signalling and functional defects of p110delta inactivation, including Akt phosphorylation, chemotaxis and proliferation. This work identifies the RhoA/ROCK pathway as a major target of p110delta-mediated PI3K signalling, and establishes for the first time that PI3K controls itself, via a feedback loop involving PTEN.  相似文献   

11.
12.
Glioblastoma multiforme (GBM) is an aggressive malignant brain tumour that is resistant to existing therapeutics. Identifying signalling pathways deregulated in GBM that can be targeted therapeutically is critical to improve the present dismal prognosis for GBM patients. In this report, we have identified that the BRG1 (Brahma-Related Gene-1) catalytic subunit of the SWI/SNF chromatin remodelling complex promotes the malignant phenotype of GBM cells. We found that BRG1 is ubiquitously expressed in tumour tissue from GBM patients, and high BRG1 expression levels are localized to specific brain tumour regions. Knockout (KO) of BRG1 by CRISPR-Cas9 gene editing had minimal effects on GBM cell proliferation, but significantly inhibited GBM cell migration and invasion. BRG1-KO also sensitized GBM cells to the anti-proliferative effects of the anti-cancer agent temozolomide (TMZ), which is used to treat GBM patients in the clinic, and selectively altered STAT3 tyrosine phosphorylation and gene expression. These results demonstrate that BRG-1 promotes invasion and migration, and decreases chemotherapy sensitivity, indicating that it functions in an oncogenic manner in GBM cells. Taken together, our findings suggest that targeting BRG1 in GBM may have therapeutic benefit in the treatment of this deadly form of brain cancer.  相似文献   

13.
Alterations in Ca2+ signaling may contribute to tumorigenesis and the mechanism of action of some anti-cancer drugs. The plasma membrane calcium-ATPase (PMCA) is a crucial controller of intracellular Ca2+ signaling. Altered PMCA expression occurs in the mammary gland during lactation and in breast cancer cell lines. Despite this, the consequences of PMCA inhibition in breast cancer cell lines have not been investigated. In this work, we used Tet-off PMCA antisense-expressing MCF-7 cells to assess the effects of PMCA inhibition in a human breast cancer cell line. At a level of PMCA inhibition that did not completely prevent PMCA-mediated Ca2+ efflux and did not induce cell death, a dramatic inhibition of cellular proliferation was observed. Fluorescence-activated cell sorting analysis indicated that PMCA antisense involves changes in cell cycle kinetics but not cell cycle arrest. We concluded that modulation of PMCA has important effects in regulating the proliferation of human breast cancer MCF-7 cells.  相似文献   

14.
Tumor necrosis factor‐alpha (TNFα) induces cancer development and metastasis, which is prominently achieved by nuclear factor‐kappa B (NF‐κB) activation. TNFα‐induced NF‐κB activation enhances cellular mechanisms including proliferation, migration, and invasion. KiSS1, a key regulator of puberty, was initially discovered as a tumor metastasis suppressor. The expression of KiSS1 was lost or down‐regulated in different metastatic tumors. However, it is unclear whether KiSS1 regulates TNFα‐induced NF‐κB activation and further tumor cell migration. In this study, we demonstrate that KiSS1 suppresses the migration of breast cancer cells by inhibiting TNFα‐induced NF‐κB pathway and RhoA activation. Both KiSS1 overexpression and KP10 (kisspeptin‐10) stimulation inhibited TNFα‐induced NF‐κB activity, suppressed TNFα‐induced cell migration and cell attachment to fibronectin in breast cancer cells while KP10 has little effect on cancer cell proliferation. Furthermore, KP10 inhibited TNFα‐induced cell migration and RhoA GTPase activation. Therefore, our data demonstrate that KiSS1 inhibits TNFα‐induced NF‐κB activation via downregulation of RhoA activation and suppression of breast cancer cell migration and invasion. J. Cell. Biochem. 107: 1139–1149, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

15.
The small GTPase Cdc42 has been implicated as an important regulator of cell migration. However, whether Cdc42 plays similar role in all cancer cells irrespective of metastatic potential remains poorly defined. Here, we show by using three different breast cancer cell lines with different metastatic potential, the role of Cdc42 in cell migration/invasion and its relationship with a number of downstream signaling pathways controlling cell migration. Small interfering RNA (siRNA)-mediated knockdown of Cdc42 in two highly metastatic breast cancer cell lines (MDA-MB-231 and C3L5) resulted in enhancement, whereas the same in moderately metastatic (Hs578T) cell line resulted in inhibition of intrinsic cellular migration/invasion. Furthermore, Cdc42 silencing in MDA-MB-231 and C3L5 but not Hs578T cells was shown to be accompanied by increased RhoA activity and phosphorylation of protein kinase C (PKC)-δ, extracellular signal regulated kinase1/2 (Erk1/2), and protein kinase A (PKA). Pharmacological inhibition of PKCδ, MEK-Erk1/2, or PKA was shown to inhibit migration of both control and Cdc42-silenced MDA-MB-231 cells. Furthermore, introduction of constitutively active Cdc42 was shown to decrease migration/invasion of MDA-MB-231 and C3L5 but increase migration/invasion of Hs578T cells. This decreased migration/invasion of MDA-MB-231 and C3L5 cells was also shown to be accompanied by the decrease in the phosphorylations of PKCδ, Erk1/2, and PKA. These results suggested that endogenous Cdc42 could exert a negative regulatory influence on intrinsic migration/invasion and some potentially relevant changes in phosphorylation of PKCδ, Erk1/2, and PKA of some aggressive breast cancer cells.  相似文献   

16.
MicroRNAs (miRNAs) are small noncoding RNAs that exert their functions by targeting specific mRNA sequences. Many studies have demonstrated that miRNAs are crucial for cancer progression, during which they can act as either oncogenes or tumor suppressors. Previous research has shown that miR-335 is downregulated in breast cancer, and it has been shown to be a breast cancer suppressor. In addition, emerging evidence indicates that erythropoietin-producing hepatocellular A4 (EphA4) is implicated in cancer cell proliferation, migration, and invasion. However, little is known about the relationship between miR-335 and EphA4 in breast cancer. In the present study, we used bioinformatic and biochemical analyses to demonstrate that EphA4 is a direct downstream target of miR-335 in human breast cancer MCF-7 and MDA-MB-23 cells and revealed that miR-335 negatively regulates the expression of EphA4 in these cells. Further investigation revealed that miR-335 overexpression inhibits MCF-7 and MDA-MB-231 cell proliferation and that this inhibition is attenuated by EphA4 coexpression. Similarly, miR-335 overexpression also inhibited growth and downregulated EphA4 expression in tumors in nude mice. Moreover, our results demonstrated that miR-335 overexpression suppresses migration and invasion in MCF-7 and MDA-MB-231 cells, an effect that was reversed by EphA4 overexpression. These findings confirmed that EphA4 is a direct target gene of miR-335 and that miR-335 suppresses breast cancer cell proliferation and motility in part by directly inhibiting EphA4 expression.  相似文献   

17.
We aimed to explore the effects of NOP16 on the pathogenesis of nasopharyngeal carcinoma (NPC) and the related mechanism. In this study, the expression level of NOP16 in NPC tissues and adjacent tissues was measured by qRT-polymerase chain reaction (PCR) and immunohistochemistry (IHC) tests. In the in vitro study, the expression levels of NOP16 and RhoA/phosphatidylinositol 3-kinase (PI3K)/Akt/c-Myc and IKK/IKB/NF-κB signalling pathway-related proteins in NPC cells were measured by qRT-PCR and Western blot (WB). CCK8 assays and colony formation assays were used to detect cell proliferation. Transwell assays were used to detect the migration and invasion ability of NPC cells. Flow cytometry and WB were used to measure the level of apoptosis. For the in vivo study, NPC xenograft models were established in nude mice, and tumour weight and volume were recorded. The expression levels of NOP16 and RhoA/PI3K/Akt/c-Myc signalling pathway-related proteins and mRNAs were measured by immunofluorescence, qRT-PCR and WB experiments. In clinical samples, the results of qRT-PCR and IHC experiments showed that the expression level of NOP16 was significantly increased in NPC tissues. In the in vitro study, the results of qRT-PCR and WB experiments showed that NOP16 was significantly increased in NPC cells. The CCK8 assay, colony formation assay, transwell assay and flow cytometry results showed that knocking out NOP16 inhibited the proliferation, migration and invasion of NPC cells and increased apoptosis. WB results showed that knocking out NOP16 inhibited the RhoA/PI3K/Akt/c-Myc and IKK/IKB/NF-κB signalling pathways. These effects were reversed by 740Y-P (PI3K activator). In the in vivo study, knockdown of NOP16 reduced tumour volume and weight and inhibited the RhoA/PI3K/Akt/c-Myc signalling pathway. In conclusion, knockdown of NOP16 inhibited the proliferation, migration and invasion of NPC cells and induced apoptosis by inhibiting the RhoA/PI3K/Akt/c-Myc and IKK/IKB/NF-κB pathways, leading to the malignant phenotype of NPC.  相似文献   

18.
X Kong  G Li  Y Yuan  Y He  X Wu  W Zhang  Z Wu  T Chen  W Wu  PE Lobie  T Zhu 《PloS one》2012,7(8):e41523
Focal adhesion kinase (FAK) is an important mediator of extracellular matrix integrin signaling, cell motility, cell proliferation and cell survival. Increased FAK expression is observed in a variety of solid human tumors and increased FAK expression and activity frequently correlate with metastatic disease and poor prognosis. Herein we identify miR-7 as a direct regulator of FAK expression. miR-7 expression is decreased in malignant versus normal breast tissue and its expression correlates inversely with metastasis in human breast cancer patients. Forced expression of miR-7 produced increased E-CADHERIN and decreased FIBRONECTIN and VIMENTIN expression in breast cancer cells. The levels of miR-7 expression was positively correlated with E-CADHERIN mRNA and negatively correlated with VIMENTIN mRNA levels in breast cancer samples. Forced expression of miR-7 in aggressive breast cancer cell lines suppressed tumor cell monolayer proliferation, anchorage independent growth, three-dimensional growth in Matrigel, migration and invasion. Conversely, inhibition of miR-7 in the HBL-100 mammary epithelial cell line promoted cell proliferation and anchorage independent growth. Rescue of FAK expression reversed miR-7 suppression of migration and invasion. miR-7 also inhibited primary breast tumor development, local invasion and metastatic colonization of breast cancer xenografts. Thus, miR-7 expression is decreased in metastatic breast cancer, correlates with the level of epithelial differentiation of the tumor and inhibits metastatic progression.  相似文献   

19.
The calpain system is required by many important physiological processes, including the cell cycle, cytoskeleton remodelling, cellular proliferation, migration, cancer cell invasion, metastasis, survival, autophagy, apoptosis and signalling, as well as the pathogenesis of a wide range of disorders, in which it may function to promote tumorigenesis. Calpains are intracellular conserved calcium-activated neutral cysteine proteinases that are involved in mediating cancer progression via catalysing and regulating the proteolysis of their specific substrates, which are important signalling molecules during cancer progression. μ-calpain, m-calpain, and their specific inhibitor calpastatin are the three molecules originally identified as comprising the calpain system and they contain several crucial domains, specific motifs, and functional sites. A large amount of data supports the roles of the calpain–calpastatin system in cancer progression via regulation of cellular adhesion, proliferation, invasion, metastasis, and cellular survival and death, as well as inflammation and angiogenesis during tumorigenesis, implying that the inhibition of calpain activity may be a potential anti-cancer intervention strategy targeting cancer cell survival, invasion and chemotherapy resistance.  相似文献   

20.
Chalcones are precursors of flavonoids and have been shown to have anti-cancer activity. Here, we identify the synthetic chalcone derivative 4′-acetoamido-4-hydroxychalcone (AHC) as a potential therapeutic agent for the treatment of glioma. Treatment with AHC reduced glioma cell invasion, migration, and colony formation in a concentration-dependent manner. In addition, AHC inhibited vascular endothelial growth factor-induced migration, invasion, and tube formation in HUVECs. To determine the mechanism underlying the inhibitory effect of AHC on glioma cell invasion and migration, we investigated the effect of AHC on the gene expression change and found that AHC affects actin dynamics in U87MG glioma cells. In actin cytoskeleton regulating system, AHC increased tropomyosin expression and stress fiber formation, probably through activation of PKA. Suppression of tropomyosin expression by siRNA or treatment with the PKA inhibitor H89 reduced the inhibitory effects of AHC on glioma cell invasion and migration. In vivo experiments also showed that AHC inhibited tumor growth in a xenograft mouse tumor model. Together, these data suggest that the synthetic chalcone derivative AHC has potent anti-cancer activity through inhibition of glioma proliferation, invasion, and angiogenesis and is therefore a potential chemotherapeutic candidate for the treatment of glioma.  相似文献   

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