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Migration Capacity (migration + capacity)
Selected AbstractsPleiotropic function of ezrin in human metastatic melanomasINTERNATIONAL JOURNAL OF CANCER, Issue 12 2009Cristina Federici Abstract The membrane cytoskeleton cross-linker, ezrin, has recently been depicted as a key regulator in the progression and metastasis of several pediatric tumors. Less defined appears the role of ezrin in human adult tumors, especially melanoma. We therefore addressed ezrin involvement in the metastatic phenotype of human adult metastatic melanoma cells. Our results show that cells resected from melanoma metastatic lesions of patients, display marked metastatic spreading capacity in SCID mice organs. Stable transfection of human melanoma cells with an ezrin deletion mutant comprising only 146 N-terminal aminoacids led to the abolishment of metastatic dissemination. In vitro experiments revealed ezrin direct molecular interactions with molecules related to metastatic functions such as CD44, merlin and Lamp-1, consistent with its participation to the formation of phagocitic vacuoles, vesicular sorting and migration capacities of melanoma cells. Moreover, the ezrin fragment capable of binding to CD44 was shorter than that previously reported, and transfection with the ezrin deletion mutant abrogated plasma membrane Lamp-1 recruitment. This study highlights key involvement of ezrin in a complex machinery, which allows metastatic cancer cells to migrate, invade and survive in very unfavorable conditions. Our in vivo and in vitro data reveal that ezrin is the hub of the metastatic behavior also in human adult tumors. © 2009 UICC [source] The green tea compound, (,)-epigallocatechin-3-gallate downregulates N-cadherin and suppresses migration of bladder carcinoma cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2007Kimberly M. Rieger-Christ Abstract Green tea has been reported as potential dietary protection against numerous cancers and has been shown to have activity in bladder tumor inhibition in different animal models. The goal of this study was to examine the effects of (,)-epigallocatechin gallate (EGCG,the major phytochemical in green tea) on growth inhibition and behavior of human bladder carcinoma cells and to identify the altered signaling pathway(s) underlying the response to EGCG exposure. EGCG inhibited the in vitro growth of invasive bladder carcinoma cells with an IC50 range of 70,87 µM. At a concentration of 20 µM, EGCG decreased the migratory potential of bladder carcinoma cells with concomitant activation of p42/44 MAPK and STAT3 and inactivation of Akt. Using biochemical inhibitors of MAPK/ERK, and siRNA to knockdown STAT3 and Akt, inhibition of migration was recorded associated with Akt but not MAPK/ERK or STAT3 signaling in bladder cells. In addition, EGCG downregulated N-cadherin in a dose-dependent manner where reduction in N-cadherin expression paralleled declining migratory potential. Continuous feeding of EGCG to mice prior to and during the establishment of bladder carcinoma xenografts in vivo revealed >50% reduction in mean final tumor volume (P,,,0.05) with no detectable toxicity. EGCG inhibited bladder carcinoma cell growth and suppressed the in vitro migration capacity of cells via downregulation of N-cadherin and inactivation of Akt signaling. Continuous administration of EGCG to mice revealed significant inhibition of tumor growth in vivo indicating a possible preventative role for green tea in bladder cancer. J. Cell. Biochem. 102: 377,388, 2007. © 2007 Wiley-Liss, Inc. [source] Adult cerebrospinal fluid inhibits neurogenesis but facilitates gliogenesis from fetal rat neural stem cellsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 14 2009Judith Buddensiek Abstract Neural stem cells (NSCs) are a promising source for cell replacement therapies for neurological diseases. Administration of NSCs into the cerebrospinal fluid (CSF) offers a nontraumatic transplantation method into the brain. However, cell survival and intraparenchymal migration of the transplants are limited. Furthermore, CSF was recently reported to be an important milieu for controlling stem cell processes in the brain. We studied the effects of adult human leptomeningeal CSF on the behavior of fetal rat NSCs. CSF increased survival of NSCs compared with standard culture media during stem cell maintenance and differentiation. The presence of CSF enhanced NSC differentiation, leading to a faster loss of self-renewal capacity and faster and stronger neurite outgrowth. Some of these effects (mainly cell survival, neurite brancing) were blocked by addition of the bone morphogenic protein (BMP) inhibitor noggin. After differentiation in CSF, significantly fewer MAP2ab+ neurons were found, but there were more GFAP+ astroglia compared with standard media. By RT-PCR analysis, we determined a decrease of mRNA of the NSC marker gene Nestin but an increase of Gfap mRNA during differentiation up to 72 hr in CSF compared with standard media. Our data demonstrate that adult human leptomeningeal CSF enhances cell survival of fetal rat NSCs during proliferation and differentiation. Furthermore, CSF provides a stimulus for gliogenesis but inhibits neurogenesis from fetal NSCs. Our data suggest that CSF contains factors such as BMPs regulating NSC behavior, and we hypothesize that fast differentiation of NSCs in CSF leads to a rapid loss of migration capacity of intrathecally transplanted NSCs. © 2009 Wiley-Liss, Inc. [source] Comparative proteomic analysis of mesenchymal stem cells derived from human bone marrow, umbilical cord, and placenta: Implication in the migrationPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 1 2009Guo Li Abstract Umbilical cord (UC) and placenta (P) have been suggested as alternatives to bone marrow (BM) as sources of mesenchymal stem cells (MSC) for cell therapy, with both UC- and P-MSC possess immunophenotypic and functional characteristics similar to BM-MSC. However, their migration capacity, which is indispensable during tissue regeneration process, is unclear. Under defined conditions, the migration capacity of BM- and P-MSC was found 5.9- and 3.2-folds higher than that of UC-MSC, respectively. By the use of 2-DE and combined MS and MS/MS analysis, six differentially expressed proteins were identified among these MSC samples, with five of them known to be involved in cell migration as migration enhancing or inhibiting proteins. Consistent with their migration capacity, the levels of migration enhancing proteins including cathepsin B, cathepsin D and prohibitin,were significantly lower in UC-MSC when compared with those in BM- and P-MSC. For the migration inhibiting proteins such as plasminogen activator inhibitor-1 (PAI-1) and manganese superoxide dismutase, higher expression was found in the UC-MSC. We also showed that the overexpression of the PAI-1 impaired the migration capacity of BM- and P-MSC while silencing of PAI-1 enhanced the migration capacity of UC-MSC. Our study indicates that PAI-1 and other migration-related proteins are pivotal in governing the migration capacity of MSC. [source] Multiple effects of bevacizumab in angiogenesis: implications for its use in age-related macular degenerationACTA OPHTHALMOLOGICA, Issue 5 2009Angela Carneiro Abstract. Purpose:, This study aimed to elucidate the precise effects of bevacizumab in all steps in the neovascularization process in endothelial cells. Methods:, Human umbilical vein endothelial cells (HUVECs) were incubated with bevacizumab at concentrations within the clinically established range or with identical amounts of excipient. Cell cytotoxicity (evaluated by MTT assay), proliferation (by BrdU incorporation assay), apoptosis (by TUNEL assay), migration (by double-chamber assay) and vessel assembly in matrigel-coated plates were assessed in vitro. Mouse plug matrigel assays were performed to confirm in vitro results. Results:, Incubation of HUVECs with bevacizumab did not present cytotoxicity. Concentrations comparable with those after intravitreal doses of bevacizumab significantly reduced proliferation and migration capacity, and increased apoptotic rates in these cells. In addition, bevacizumab led to a significant decrease in the assembly of capillary-like structures on matrigel assay in comparison with excipient-treated cells. Further substantiating these in vitro findings, bevacizumab also inhibited angiogenesis in a mouse plug matrigel assay, as evaluated by haemoglobin content levels. Conclusions:, These results demonstrate that clinical doses of bevacizumab are able to prevent several steps of the angiogenic process. Bevacizumab is thus currently recommended for treating disorders that present augmented angiogenesis. [source] Rosiglitazone via upregulation of Akt/eNOS pathways attenuates dysfunction of endothelial progenitor cells, induced by advanced glycation end productsBRITISH JOURNAL OF PHARMACOLOGY, Issue 8 2009Chun Liang Background and purpose:, Advanced glycation end products (AGEs) and endothelial progenitor cells (EPCs) play key roles in pathogenesis of diabetes-related vascular complications. AGEs can induce dysfunction in EPCs. The peroxisome proliferator-activated receptor-gamma (PPAR,) agonists are widely used in the treatment of type 2 diabetes, and it remains unknown if they could attenuate EPC dysfunction induced by AGEs. Experimental approach:, EPCs isolated from healthy adults were cultured with various concentrations of AGEs (0, 50, 100 and 200 mg·L,1) with or without rosiglitazone (10 nM), antibody for the receptors for AGE-human serum albumin (anti-receptor for advanced glycation end products (RAGE); 50 µg·mL,1), phosphatidylinositol-3-kinase (PI3K) inhibitor (LY294002, 5 µM), nitric oxide (NO) synthase inhibitor (L-NG -nitro-arginine methyl ester (L-NAME), 100 µM) or sodium nitroprusside (SNP, 25 µM). Proliferation, apoptosis, cell adhesion, migration and NO production in EPCs were assessed, and expressions of endothelial NO synthase (eNOS) and Akt were determined. Key results:, Number, proliferation/migration capacities, eNOS and Akt phosphorylation as well as NO synthesized by EPCs were increased by rosiglitazone and reduced by AGEs. AGEs promoted while rosiglitazone reduced EPC apoptosis. The AGE-induced effects were significantly ameliorated by pre-incubation with rosiglitazone, RAGE antibody and SNP. The beneficial effects of rosiglitazone could be blocked by pretreatment with L-NAME and LY294002. Conclusions and implications:, The PPAR, agonist rosiglitazone increased EPC function and attenuated EPC dysfunction induced by AGEs via upregulating the Akt-eNOS signal pathways of EPCs. [source] | |||||||||||||