scholarly journals miR-21 increases c-kit+ cardiac stem cell proliferation in vitro through PTEN/PI3K/Akt signaling

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2859 ◽  
Author(s):  
Bei Shi ◽  
Wenwen Deng ◽  
Xianping Long ◽  
Ranzun Zhao ◽  
Yan Wang ◽  
...  
Keyword(s):  
Mrna Level ◽  
Cell Types ◽  
Ischemic Myocardium ◽  
Akt Pathway ◽  
Pi3k Inhibitor Ly294002 ◽  
Over Expression ◽  
Tensin Homolog ◽  
Survival Effect ◽  
Proliferation In Vitro

The low survival rate of cardiac stem cells (CSCs) in the ischemic myocardium is one of the obstacles in ischemic cardiomyopathy cell therapy. The MicroRNA (miR)-21 and one of its target protein, the tensin homolog deleted on chromosome ten (PTEN), contributes to the proliferation of many kinds of tissues and cell types. It is reported that miR-21 promotes proliferation through PTEN/PI3K/Akt pathway, but its effects on c-kit+ CSC remain unclear. The authors hypothesized that miR-21 promotes the proliferation in c-kit+ CSC, and evaluated the involvement of PTEN/PI3K/Akt pathway in vitro. miR-21 up-regulation with miR-21 efficiently mimics accelerated cell viability and proliferation in c-kit+ CSC, which was evidenced by the CCK-8, EdU and cell cycle analyses. In addition, the over-expression of miR-21 in c-kit+ CSCs notably down-regulated the protein expression of PTEN although the mRNA level of PTEN showed little change. Gain-of-function of miR-21 also increased the phosphor-Akt (p-Akt) level. Phen, the selective inhibitor of PTEN, reproduced the pro-proliferation effects of miR-21, while PI3K inhibitor, LY294002, totally attenuated the pro-survival effect of miR-21. These results indicate that miR-21 is efficient in promoting proliferation in c-kit+ CSCs, which is contributed by the PTEN/PI3K/Akt pathway. miR-21 holds the potential to facilitate CSC therapy in ischemic myocardium.

1442: CXCL12 Over-Expression and Secretion by Aging Fibroblasts Stimulates Human Prostate Epithelial Proliferation in Vitro

2006 ◽  
Vol 175 (4S) ◽  
pp. 466-466
Author(s):  
Jill A. Macoska ◽  
Lesa Begley ◽  
Christine Monteleon ◽  
James W. MacDonald ◽  
Rajal B. Shah
Keyword(s):  
Human Prostate ◽  
Epithelial Proliferation ◽  
Over Expression ◽  
Proliferation In Vitro

Abstract 3653: Akt3 Offers Stronger Protection than Akt1 Against Brain Injury by Differentially Promoting Mtor Protein Levels In Both In Vitro and In Vivo Stroke Models

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Rong Xie ◽  
Michelle Cheng ◽  
Mei Li ◽  
Robert Sapolsky ◽  
Heng Zhao
Keyword(s):  
Gene Transfer ◽  
Western Blotting ◽  
Ischemic Injury ◽  
Akt Pathway ◽  
Over Expression ◽  
Protein Levels ◽  
Akt Isoforms ◽  
The Brain

Background and Objective: Akt is a serine-threonine kinase that plays critical role in promoting cell survival. Akt consists of three isoforms (Akt1, 2, 3), with Akt3 predominantly expressed in the brain. Although Akt pathway has been shown to mediate neuronal survival in cerebral ischemic injury, it is unclear how these Akt isoforms contribute to neuronal protection, and whether exogenous Akt can protect the brain against ischemic injury or not. In this study, we over-expressed Akt isoforms and its downstream signaling proteins such as FKHR and PRAS40 to investigate the role of the Akt pathway along with its potential relationship with the mTOR pathway in stroke. Methods: Sprauge Dawley rats (250∼280g) were used for all studies. A lentiviral vector consists of a CMV promoter driving IRES-eGFP was used to clone an active Akt 1 and 3 (cAKt 1 and 3), dominant-negative Akt (AktDN), active FKHR (AAA FKHR), and PRAS40. Lentivirus expressing these genes were added to primary mixed cortical cultures for two days prior to oxygen glucose deprivation (OGD) (MOI=1:5). Neuronal survival was measured by LDH release. Lentivirus were stereotaxically injected into the cortex, and rats were subjected to focal ischemia induced by distal MCA occlusion combined with bilateral CCA occlusion. Western blotting and immunofluorescent confocal microscopy were used to detect the expression of Akt isoforms and other proteins in both the Akt and mTOR pathways. Results: Western blotting analysis showed that both endogenous Akt1 and 3 proteins degraded as early as 1 h after stroke, while Akt2 protein remained unchanged until 24 h after stroke. In vitro studies showed that over-expression of both constitutively active cAkt1 and cAkt3 decreased LDH release after OGD, while AktDN worsened neuronal death ( P <0.05). In vivo over-expression of cAkt1, cAkt3 and PRAS40 reduced infarct size after stroke ( P <0.01). Gene transfer of cAkt1 and 3 also promoted protein levels of pAkt (phosphorylated Akt), pPRAS40, pFKHR, pPTEN, pmTOR, but not pGSK3β. Both in vitro and in vivo studies showed that over-expression of cAkt3 resulted in a stronger protection than cAkt1 ( P <0.05). Interestingly, cAkt3 gene transfer preserved both endogenous protein levels of Akt1 and 3, whereas cAkt1 gene transfer only preserved endogenous Akt1. Furthermore, cAkt3 promoted higher pmTOR levels than cAkt1. Treatment of rapamycin, an mTOR inhibitor, blocked the protective effects of both cAkt1 and cAkt3 both in vitro and in vivo. Conclusion: Lentiviral-mediated overexpression of cAkt3 confers stronger protection than that of cAkt1, by maintaining both endogenous Akt1 and Akt3, as well as promoting higher mTOR activities after stroke.

scholarly journals Downregulation of NCL attenuates tumor formation and growth in cervical cancer by targeting the PI3K/AKT pathway

2021 ◽  
Author(s):  
Jun Ying ◽  
Ruowang Pan ◽  
Zhouhao Tang ◽  
Jiayin Zhu ◽  
Ping Ren ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Opposite Effect ◽  
Vital Role ◽  
Tumor Formation ◽  
Akt Pathway ◽  
Pi3k Inhibitor Ly294002 ◽  
Proliferation And Apoptosis ◽  
Underlying Mechanisms

AbstractNucleolin (NCL, C23) is a multifunctional phosphoprotein that plays a vital role in modulating the survival, proliferation and apoptosis of cancer cells. However, the effects of NCL on cervical cancer and the underlying mechanisms behind this are poorly understood. In the study presented here, Hela cells were transfected with shRNAs targeting the endogenous NCL gene (sh-NCL-Hela). NCL knockdown inhibited cell proliferation and promoted apoptosis both in vivo and in vitro. Mechanistic studies revealed that NCL knockdown inhibited the PI3K/AKT pathway by upregulating FGF, ITGA, TNXB, VEGF, Caspase 3, and Bax, as well as by downregulating AKT, GNB4, CDK6, IL6R, LAMA, PDGFD, PPP2RSA and BCL-2. In addition, the expression levels of apoptosis-related genes after using a PI3K inhibitor LY294002 were consistent with shRNA studies, while treatment with a 740Y-P agonist showed the opposite effect. Altogether, this study uncovered that downregulation of NCL may be a novel treatment strategy for cervical cancer.

scholarly journals Evidence for an inhibitory role of bone morphogenetic protein(s) in the follicular–luteal transition in cattle

Reproduction ◽  
2009 ◽  
Vol 137 (1) ◽  
pp. 67-78 ◽  
Author(s):  
Amjad R Kayani ◽  
Claire Glister ◽  
Philip G Knight
Keyword(s):  
Bone Morphogenetic Proteins ◽  
Mrna Level ◽  
Protein S ◽  
Transcript Abundance ◽  
Cell Types ◽  
Suppressive Effect ◽  
Cell Number ◽  
Activin A ◽  
Activin Receptors

Bone morphogenetic proteins (BMPs) and their receptors are expressed in ovarian theca cells (TC) and granulosa cells (GC) and BMPs have been implicated in the regulation of several aspects of follicle development including thecal androgen production and granulosal oestrogen production. Their potential involvement in luteal function has received less attention. In this study, we first compared relative abundance of mRNA transcripts for BMPs, activin-βA and BMP/activin receptors in bovine corpus luteum (CL) and follicular theca and granulosa layers before undertaking functional in vitro experiments to test the effect of selected ligands (BMP6 and activin A) on luteinizing bovine TC and GC. Relative to β-actin transcript abundance, CL tissue contained more BMP4 and -6 mRNA than granulosa, more BMP2 mRNA than theca but much less activin-βA mRNA than both granulosa and theca. Transcripts for all seven BMP/activin receptors were readily detected in each tissue and two transcripts (BMPRII, ActRIIA) were more abundant in CL than either theca or granulosa, consistent with tissue responsiveness. In vitro luteinization of TC and GC from antral follicles (4–6 mm) was achieved by culturing with 5% serum for 6 days. Treatment with BMP6 (0, 2, 10, and 50 ng/ml) and activin A (0, 2, 10 and 50 ng/ml) under these conditions dose-dependently suppressed forskolin-induced progesterone (P4) secretion from both cell types without affecting cell number. BMP6 reduced forskolin-stimulated upregulation of STAR mRNA and raised ‘basal’ CYP17A1 mRNA level in theca-lutein cells without affecting expression of CYP11A1 or hydroxy-Δ-5-steroid dehydrogenase, 3 β- and steroid Δ-isomerase 1 (HSD3B1). In granulosa-lutein cells, STAR transcript abundance was not affected by BMP6, whereas forskolin-induced expression of CYP11A1, HSD3B1, CYP19A1 and oxytocin transcripts was reduced. In both cell types, follistatin attenuated the suppressive effect of activin A and BMP6 on forskolin-induced P4 secretion but had no effect alone. Granulosa-lutein cells secreted low levels of endogenous activin A (∼1 ng/ml); BMP6 reduced this, while raising follistatin secretion thus decreasing activin A:follistatin ratio. Collectively, these findings support inhibitory roles for BMP/activin signalling in luteinization and steroidogenesis in both TC and GC.

scholarly journals miR-21 Reduces Hydrogen Peroxide-Induced Apoptosis in c-kit+Cardiac Stem Cells In Vitro through PTEN/PI3K/Akt Signaling

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Wenwen Deng ◽  
Yan Wang ◽  
Xianping Long ◽  
Ranzun Zhao ◽  
Zhenglong Wang ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Stem Cells ◽  
Caspase 3 ◽  
Mrna Level ◽  
Cell Types ◽  
Akt Signaling ◽  
Selective Inhibitor ◽  
Cardiac Stem Cells ◽  
Induced Apoptosis

The low survival rate of cardiac stem cells (CSCs) in the infarcted myocardium hampers cell therapy for ischemic cardiomyopathy. MicroRNA-21 (miR-21) and one of its target proteins, PTEN, contribute to the survival and proliferation of many cell types, but their prosurvival effects in c-kit+CSC remain unclear. Thus, we hypothesized that miR-21 reduces hydrogen peroxide- (H2O2-) induced apoptosis in c-kit+CSC and estimated the contribution of PTEN/PI3K/Akt signaling to this oxidative circumstance. miR-21 mimics efficiently reduced H2O2-induced apoptosis in c-kit+CSC, as evidenced by the downregulation of the proapoptosis proteins caspase-3 and Bax and upregulation of the antiapoptotic Bcl-2. In addition, the gain of function of miR-21 in c-kit+CSC downregulated the protein level of PTEN although its mRNA level changed slightly; in the meantime, miR-21 overexpression also increased phospho-Akt (p-Akt). The antiapoptotic effects of miR-21 were comparable with Phen (bpV), the selective inhibitor of PTEN, while miR-21 inhibitor or PI3K’s inhibitor LY294002 efficiently attenuated the antiapoptotic effect of miR-21. Taken together, these results indicate that the anti-H2O2-induced apoptosis effect of miR-21 in c-kit+CSC is contributed by PTEN/PI3K/Akt signaling. miR-21 could be a potential molecule to facilitate the c-kit+CSC therapy in ischemic myocardium.

Involvement of a ferroprotein sensor in hypoxia-mediated inhibition of neutrophil apoptosis

Blood ◽  
2002 ◽  
Vol 100 (8) ◽  
pp. 3008-3016 ◽  
Author(s):  
Katy I. Mecklenburgh ◽  
Sarah R. Walmsley ◽  
Andrew S. Cowburn ◽  
Michael Wiesener ◽  
Benjamin J. Reed ◽  
...  
Keyword(s):  
Oxygen Sensing ◽  
Hypoxia Inducible Factor ◽  
Glucose Deprivation ◽  
Cell Types ◽  
Human Neutrophils ◽  
Neutrophil Apoptosis ◽  
Low Oxygen ◽  
Sensing Mechanism ◽  
Survival Effect

Neutrophil apoptosis represents a major mechanism involved in the resolution of acute inflammation. In contrast to the effect of hypoxia observed in many other cell types, oxygen deprivation, as we have shown, causes a profound but reversible delay in the rate of constitutive apoptosis in human neutrophils when aged in vitro. This effect was mimicked by exposing cells to 2 structurally unrelated iron-chelating agents, desferrioxamine (DFO) and hydroxypyridines (CP-94), and it appeared specific for hypoxia in that no modulation of apoptosis was observed with mitochondrial electron transport inhibitors, glucose deprivation, or heat shock. The involvement of chelatable iron in the oxygen-sensing mechanism was confirmed by the abolition of the DFO and CP-94 survival effect by Fe2+ ions. Although hypoxia inducible factor-1α (HIF-1α) mRNA was identified in freshly isolated neutrophils, HIF-1α protein was only detected in neutrophils incubated under hypoxic conditions or in the presence of DFO. Moreover, studies with cyclohexamide demonstrated that the survival effect of hypoxia was fully dependent on continuing protein synthesis. These results indicate that the neutrophil has a ferroprotein oxygen-sensing mechanism identical to that for erythropoietin regulation and results in HIF-1α up-regulation and profound but reversible inhibition of neutrophil apoptosis. This finding may have important implications for the resolution of granulocytic inflammation at sites of low-oxygen tension.

Down-Regulation of HO-1 Promoted Apoptosis Induced By Decitabine Via Increasing p15INK4B Promoter Demethylation in myelodysplastic syndrome

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5213-5213 ◽  
Author(s):  
Jishi Wang ◽  
Dan Ma ◽  
Qin Fang ◽  
Ping Wang ◽  
Rui Gao ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Mononuclear Cells ◽  
Conflicts Of Interest ◽  
Mrna Level ◽  
Methylation Status ◽  
S Phase ◽  
Heme Oxygenase 1 ◽  
Down Regulation ◽  
Over Expression

Abstract Background: Decitabine, reverts hypermethylation of p15INK4B gene in vitro, was used to improves cytopenias and blast excess in over 50% of patients with high-risk myelodys plastic syndrome (MDS). In this study, over-expression of Heme Oxygenase-1(HO-1) was found in MDS cells line SKM-1 cells, and it was closely related to resistance to apoptosis induced by decitabine. Objective: we aimed to further investigated what role of HO-1 exactly played in apoptosis induced by low-does of decitabine in MDS. Method: CCK-8 kits was used to determine the proliferation inhibition of SKM-1 cells. Flow cytometry was used for analyzing cell proliferation rate and apoptosis. The methylation status and expression of P15INK4B in mRNA and protein levels were measured by methylation-specifc polymerase chain reaction (PCR [MSP]). Apoptosis relative factors expression were detected by real-time transcription and Western blot. Result: Up-regulation of HO-1 by transfected it into SKM-1 cells via lenti-virus vector promoted proliferation and protected cells against apoptosis. In contrast, down-regulation of HO-1 enhanced decitabine-induced apoptosis but reduced accumulation of S phase in cell cycle. To explore the mechanism, we detected cell cycle relative protein expression after SKM-1 cells were treated by decitabine in each group. As a result, over-expression of p15 INK4B and CDK4 were observed in SKM-1 cells which HO-1 was inhibited. And p15 INK4B and CDK4 expression-dependent apoptosis was related to caspase3 pathway. Even though HO-1 was silenced, but apoptotic rate never increased as caspase3 pathway was blocked. Conclusion: As we known that p15 INK4B is a keypoint to regulate S phase of cell cycle, in our study, more obvious demethylation of p15 INK4B was seen in group of SKM-1 cells in which HO-1 was down-regulated. It’s equally in patients’ mononuclear cells who suffered from MDS. The worse the prognosis of MDS was judged, the more the mRNA level of HO-1 expressed. In conclusion, over-expression of HO-1 indicated resistance to demethylation of p15 INK4B induced by decitabine. Disclosures No relevant conflicts of interest to declare.

scholarly journals Mir-22-3p Enhances the Chemosensitivity of Gastrointestinal Stromal Tumor Cell Lines to Cisplatin through PTEN/PI3K/Akt Pathway

2018 ◽  
Author(s):  
Yugang Xu ◽  
Ming Cheng ◽  
Lei Mi ◽  
Yunping Qiu ◽  
Wenli Hao ◽  
...  
Keyword(s):  
Gastrointestinal Stromal Tumor ◽  
Cell Line ◽  
Mrna Level ◽  
Stromal Tumor ◽  
Cell Counting ◽  
Akt Pathway ◽  
Mrna Levels ◽  
Migration Ability ◽  
Related Factors ◽  
Tensin Homolog

Mir-22-3p is associated with many important biological processes, including neuroprotection, tumorigenesis, and various other tumor progressions. Our study aimed to investigate the roles of Mir-22-3p in chemosensitivity of gastrointestinal stromal tumor (GIST-T1) cells to cisplatin and explore its underlying mechanisms. Mir-22-3p high-expressing cell line was established by transfecting GIST-T1 cell line cells with Mir-22-3p mimic. After treatment with cisplatin (10 μM), Cell counting kits-8 (CCK-8) method was used to detect the cell viability. Flow cytometry was applied to measure the degree of cell apoptosis. Scratch wound healing test was used to detect the migration ability of cells. The protein and mRNA levels of the phosphatase and tensin homolog deleted on chromosome ten (PTEN)/phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) pathway-related factors were analyzed by Western blot and qRT-PCR. The mRNA level of Mir-22-3p was increased in transfected GIST-T1 cells compared with that in control cells. The survival rate and Bcl-2/Bax ratio of GIST-T1 cells treated with both Mir-22-3p analogue and cisplatin were significantly decreased, while the apoptosis rate and protein level of caspase-3 were significantly increased (p<0.05). In addition, the mRNA and protein levels of PTENwere significantly increased in cells treated with both Mir-22-3p analogue and cisplatin (p<0.05), while the expression levels of PI3K and Akt were significantly decreased (p<0.05). Mir-22-3p overexpression can increase the chemosensitivity of cisplatin in human gastrointestinal stromal tumor cells by PTEN/PI3K/Akt pathway.

scholarly journals Exosome-transferred LINC01559 promotes the progression of gastric cancer via PI3K/AKT signaling pathway

2020 ◽  
Vol 11 (9) ◽  
Author(s):  
Liyan Wang ◽  
Xiaotong Bo ◽  
Xiaoyuan Yi ◽  
Xuhua Xiao ◽  
Qinghua Zheng ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Phosphoglycerate Kinase ◽  
The Cancer Genome Atlas ◽  
Akt Pathway ◽  
Protein Coding ◽  
Polycomb Repressive Complex 2 ◽  
Tensin Homolog ◽  
Potential Biomarker ◽  
And Function

Abstract Increasing evidence indicates that long non-coding RNAs (lncRNAs) are associated with the progression of human cancers. However, the expression level and function of LINC01559 (long intergenic non-protein coding RNA 1559) in gastric cancer (GC) are rarely reported. Here we found that LINC01559 was upregulated in GC tissues based on GEPIA (Gene Expression Profiling Interactive Analysis) and TCGA (The Cancer Genome Atlas) databases. Also, LINC01559 was expressed at a lower level in GC cells than in mesenchymal stem cells (MSCs). In vitro experiments revealed that silencing LINC01559 remarkably hindered GC cell proliferation, migration and stemness. Then, we identified that LINC01559 was transmitted form MSCs to GC cells via the exosomes. Immunofluorescence staining and electron microscope validated the existence of exosomes in GC cells. Mechanistically, LINC01559 sponged miR-1343-3p to upregulate PGK1 (phosphoglycerate kinase 1), therefore activating PI3K/AKT pathway. Moreover, LINC01559 recruited EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit) to PTEN (phosphatase and tensin homolog) promoter, inducing the methylation of PTEN promoter and finally resulting in PTEN repression. Of note, LINC01559 targeted both PGK1 and PTEN to promote GC progression by activating PI3K/AKT pathway. Taken together, our study demonstrated that LINC01559 accelerated GC progression via upregulating PGK1 and downregulating PTEN to trigger phosphatidylinositol 3-kinase/AKT serine/threonine kinase (PI3K/AKT) pathway, indicating LINC01559 as a potential biomarker for GC treatment.

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