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PI3K信号通路通过Skp2、p27调节肝癌细胞的增殖 总被引:2,自引:0,他引:2
探讨磷脂酰肌醇3-激酶(PI3K)信号通路调节肝癌细胞增殖的机制.用LY294002特异性阻断PI3K信号通路后,人肝癌细胞(SMMC-7721)的增殖明显被抑制.RT-PCR及蛋白质印迹结果显示,LY294002增加了p27蛋白的表达,但不影响p27的mRNA表达.在LY294002处理的细胞中转入p27的RNAi质粒以干扰p27蛋白的表达后,肝癌细胞的增殖能力可部分恢复.放线菌酮(Chx)处理实验表明,阻断PI3K信号通路使p27蛋白的半衰期延长,稳定性增加.进一步研究发现,LY294002可抑制介导p27蛋白降解的关键分子Skp2的mRNA表达,还可缩短Skp2蛋白的半衰期,降低Skp2蛋白的稳定性.但在SMMC-7721中分别转染PI3K下游重要靶分子Akt的持续激活和失活突变体,却并不影响p27蛋白的表达.这些结果表明,PI3K信号通路在转录及翻译后水平调节Skp2的表达而影响p27蛋白的降解,从而调节肝癌细胞的增殖,但Akt并没有参与这种调节. 相似文献
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So Yeun Kim Seung-Jun Yoo Gabriele V Ronnett Eun-Kyoung Kim Cheil Moon 《Molecules and cells》2015,38(6):535-539
Olfactory stimulation activates multiple signaling cascades in order to mediate activity-driven changes in gene expression that promote neuronal survival. To date, the mechanisms involved in activity-dependent olfactory neuronal survival have yet to be fully elucidated. In the current study, we observed that olfactory sensory stimulation, which caused neuronal activation, promoted activation of the phosphatidylinositol 3′-kinase (PI3K)/Akt pathway and the expression of Bcl-2, which were responsible for olfactory receptor neuron (ORN) survival. We demonstrated that Bcl-2 expression increased after odorant stimulation both in vivo and in vitro. We also showed that odorant stimulation activated Akt, and that Akt activation was completely blocked by incubation with both a PI3K inhibitor () and Akt1 small interfering RNA. Moreover, blocking the PI3K/Akt pathway diminished the odorant-induced Bcl-2 expression, as well as the effects on odorant-induced ORN survival. A temporal difference was noted between the activation of Akt1 and the expression of Bcl-2 following odorant stimulation. Blocking the PI3K/Akt pathway did not affect ORN survival in the time range prior to the increase in Bcl-2 expression, implying that these two events, activation of the PI3K pathway and Bcl-2 induction, were tightly connected to promote post-translational ORN survival. Collectively, our results indicated that olfactory activity activated PI3K/Akt, induced Bcl-2, and promoted long term ORN survival as a result. LY294002相似文献
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Arctigenin,a Natural Lignan Compound,Induces Apoptotic Death of Hepatocellular Carcinoma Cells via Suppression of PI3‐K/Akt Signaling
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Xiaoxin Jiang Leping Zeng Jufang Huang Hui Zhou Yubin Liu 《Journal of biochemical and molecular toxicology》2015,29(10):458-464
In this study, we explored the cytotoxic effects of arctigenin, a natural lignan compound, on human hepatocellular carcinoma (HCC) cells and check the involvement of phosphatidylinositol 3‐kinase (PI3‐K)/Akt signaling. HCC cells were treated with different concentrations of arctigenin and cell viability and apoptosis were assessed. Manipulating Akt signaling was used to determine its role in the action of arctigenin. Arctigenin significantly inhibited the viability of HCC cells in a concentration‐dependent manner. Arctigenin induced apoptosis and activation of caspase‐9 and ‐3. Overexpression of a constitutively active Akt mutant blocked arctigenin‐induced apoptosis. Combinational treatment with arctigenin and the PI3‐K inhibitor LY294002 significantly enhanced apoptosis. Arctigenin reduced the expression of Bcl‐xL, Mcl‐1, and survivin and the phosphorylation of mTOR and S6K, which were significantly reversed by overexpression of constitutively active Akt. This is the first report about the anticancer activity of arctigenin in HCC cells, which is mediated by inactivation of PI3‐K/Akt signaling. 相似文献
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CDDP [cisplatin or cis-diamminedichloroplatinum(II)] and CDDP-based combination chemotherapy have been confirmed effective against gastric cancer. However, CDDP efficiency is limited because of development of drug resistance. In this study, we found that PAK4 (p21-activated kinase 4) expression and activity were elevated in gastric cancer cells with acquired CDDP resistance (AGS/CDDP and MKN-45/CDDP) compared with their parental cells. Inhibition of PAK4 or knockdown of PAK4 expression by specific siRNA (small interfering RNA)-sensitized CDDP-resistant cells to CDDP and overcome CDDP resistance. Combination treatment of [the inhibitor of PI3K (phosphoinositide 3-kinase)/Akt (protein kinase B or PKB) pathway] or PD98509 {the inhibitor of MEK [MAPK (mitogen-activated protein kinase)/ERK (extracellular-signal-regulated kinase) kinase] pathway} with PF-3758309 (the PAK4 inhibitor) resulted in increased CDDP efficacy compared with LY294002 or PD98509 alone. However, after the concomitant treatment of LY294002 and PD98509, PF-3758309 administration exerted no additional enhancement of CDDP cytotoxicity in CDDP-resistant cells. Inhibition of PAK4 by PF-3758309 could significantly suppress MEK/ERK and PI3K/Akt signalling in CDDP-resistant cells. Furthermore, inhibition of PI3K/Akt pathway while not MEK/ERK pathway could inhibit PAK4 activity in these cells. The in vivo results were similar with those of in vitro. In conclusion, these results indicate that PAK4 confers CDDP resistance via the activation of MEK/ERK and PI3K/Akt pathways. PAK4 and PI3K/Akt pathways can reciprocally activate each other. Therefore, PAK4 may be a potential target for overcoming CDDP resistance in gastric cancer. LY294002相似文献
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Our previous studies demonstrated that glimepiride enhanced the proliferation and differentiation of osteoblasts and led to activation of the PI3K/Akt pathway. Recent genetic evidence shows that endothelial nitric oxide synthase (eNOS) plays an important role in bone homeostasis. In this study, we further elucidated the roles of eNOS, PI3K and Akt in bone formation by osteoblasts induced by glimepiride in a high glucose microenvironment. We demonstrated that high glucose (16.5 mM) inhibits the osteogenic differentiation potential and proliferation of rat osteoblasts. Glimepiride activated eNOS expression in rat osteoblasts cultured with two different concentrations of glucose. High glucose-induced osteogenic differentiation was significantly enhanced by glimepiride. Down-regulation of PI3K P85 levels by treatment with (a PI3K inhibitor) led to suppression of P-eNOS and P-AKT expression levels, which in turn resulted in inhibition of RUNX2, OCN and ALP mRNA expression in osteoblasts induced by glimepiride at both glucose concentrations. ALP activity was partially inhibited by 10 µM LY294002. Taken together, our results demonstrate that glimepiride-induced osteogenic differentiation of osteoblasts occurs via eNOS activation and is dependent on the PI3K/Akt signaling pathway in a high glucose microenvironment. LY294002相似文献
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Won Jun Lee 《Molecules and cells》2009,28(5):495-499
Although insulin-like growth factor-I (IGF-I) and androgen receptor (AR) are well known effectors of skeletal muscle, the
molecular mechanism by which signaling pathways integrating AR and IGF-I in skeletal muscle cells has not been previously
examined. In this study, the role of PI3K/Akt on IGF-I-induced gene expression and activation of AR in skeletal muscle cells
was investigated. C2C12 cells were treated with IGF-I in the absence or presence of inhibitors of PI3K/Akt pathway (LY294002
and Wortmannin). Inhibition of the PI3K/Akt pathway with LY294002 or Wortmannin led to a significant decrease in IGF-I-induced
AR phosphorylation and total AR protein expression. Furthermore, IGF-I-induced AR mRNA and skeletal α-actin mRNA were blocked
by LY294002 or Wortmannin. Confocal images showed that IGF-I-induced AR translocation from cytosol to nucleus was inhibited
significantly in response to treatment with LY294002 or Wortmannin. The present results suggest that modulating effect of
IGF-I on AR gene expression and activation in C2C12 mouse skeletal muscle cells is mediated at least in part by the PI3K/Akt
pathway. 相似文献
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As embryonic progenitors for the gametes, PGCs (primordial germ cells) proliferate and develop under strict regulation of numerous intrinsic and external factors. As the most active natural metabolite of vitamin A, all-trans RA (retinoic acid) plays pivotal roles in regulating development of various cells. The proliferating action of RA on PGCs was investigated along with the intracellular PI3K (phosphoinositide 3-kinase)/Akt (protein kinase B; also known as Akt)-mediated NF-κB (nuclear factor κB) signalling cascade. The results show that RA significantly promoted PGC proliferation in a dose- and time-dependent manner, confirmed by BrdU (bromodeoxyuridine) incorporation and cell cycle analysis. However, this promoting effect was attenuated by sequential inhibitors of LY294002 for PI3K, KP372-1 for Akt and SN50 for NF-κB respectively. Western blot analysis showed increased Akt phosphorylation (Ser473) of PGCs after stimulation with RA, but this was abolished by LY294002 or KP372-1. Treatment with RA increased expression of NF-κB and decreased IκBα (inhibitory κBα) expression, which were inhibited by SN50. Blockade of PI3K or Akt activity inhibited NF-κB translocation from the cytoplasm to the nucleus. Finally, mRNA expression of cell cycle regulating genes [cyclin D1 and E, CDK6 (cyclin-dependent kinase 6) and CDK2] was up-regulated in the RA-treated cells. This stimulation was also markedly retarded by combined treatment with LY294002, KP372-1 and SN50. These results suggest that RA activates the PI3K/Akt and NF-κB signalling cascade to promote proliferation of the cultured chicken PGCs. 相似文献
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Jie Zhang Changling Ding Shuping Zhang Yangyang Xu 《Journal of cellular and molecular medicine》2020,24(16):8977-8985
Astaxanthin (ATX), which is the most abundant flavonoid in propolis, has previously shown neuroprotective properties against cerebral ischaemia‐induced apoptosis. However, the mechanisms by which ATX mediates its therapeutic effects are unclear. At present, we explored the underlying mechanisms involved in the protective effects of ATX via the phosphoinositide 3‐kinase (PI3K)/Akt/glycogen synthase kinase 3 beta (GSK3β)/nuclear factor erythroid 2‐related factor 2 (Nrf2) signalling pathway in SH‐SY5Y cells. The PI3K/Akt inhibitor LY294002 and GSK3β inhibitor LiCl were employed in this study. Pre‐treatment with ATX for 24 hours significantly decreased the oxygen and glucose deprivation (OGD)‐induced viability loss, reduced the proportion of apoptosis and regulated OGD‐mediated reactive oxygen species (ROS) production. Furthermore, ATX suppressed OGD‐caused mitochondrial membrane potential and decomposition of caspase‐3 to cleaved caspase‐3, and heightened the B‐cell lymphoma 2 (Bcl‐2)/Bax ratio. PI3K/Akt/GSK3β/Nrf2 signalling pathway activation in SH‐SY5Y cells was verified by Western blot. ATX and LiCl treatment raised the protein levels of p‐Akt, p‐GSK3β, nucleus Nrf2 and haeme oxygenase 1 (HO‐1). However, these protein expression levels decreased by treatment of LY294002. The above in vitro data indicate that ATX can confer neuroprotection against OGD‐induced apoptosis via the PI3K/Akt/GSK3β/Nrf2 signalling pathway. 相似文献
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Xin-Fang Wang Bei-Hao Zhang Xiao-Qing Lu Rui-Qiang Wang 《Journal of cellular physiology》2019,234(2):1567-1577
Between 1% and 15% of people are globally affected by kidney stones, and this disease has become more common since the 1970s. Therefore, this study aims to investigate the effects of gastrin-releasing peptide receptor (GRPR) gene silencing via the PI3K/Akt signaling pathway on the development of the epithelial–mesenchymal transition (EMT) and formation of a calcium oxalate crystal in renal tubular epithelial cells (TECs) of kidney stones. A total of 70 clean and healthy C57BL/6J mice were assigned into the normal ( n = 10) and kidney stones groups ( n = 60). The underlying regulatory mechanisms of GRPR were analyzed in concert with the treatment of shGRPR-1, LY294002, and shGRPR-1 + LY294002 in TECs isolated from mice with kidney stones. A series of experiments were conducted for the measurement of urinary oxalate and urinary calcium, the renal calcium salt deposition, the positive rate of GRPR, the expressions of renal TECs related genes and calcium oxalate regulation related genes, and the growth of calcium crystals induced by cells. After treatment of shGRPR-1 and shGRPR-1 + LY294002, levels of urinary oxalate and urinary calcium in the serum, as well as positive rate of GRPR, became relatively low, levels of E-cadherin enhanced, whereas levels of Akt, PI3K, GRPR, extents of PI3K and Akt phosphorylation, α-SMA, Vimentin and FSP-1, OPN, MCP-1, and CD44 decreased and a number of crystals reduced. Taken together, we conclude that GRPR gene silencing suppresses the development of the EMT and formation of the calcium oxalate crystal in renal TECs of kidney stones through the inactivation of the PI3K/Akt signaling pathway. 相似文献
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Varicella-zoster virus (VZV) activates the phosphatidylinositol 3-kinase (PI3K)/Akt pathway and alters cell cycle progression, but the viral protein(s) responsible for these activities is unknown. We previously reported that the VZV open reading frame 12 (ORF12) protein triggers phosphorylation of ERK. Here, we demonstrate that the VZV ORF12 protein also activates the PI3K/Akt pathway to regulate cell cycle progression. Transfection of cells with a plasmid expressing the ORF12 protein induced phosphorylation of Akt, which was dependent on PI3K. Infection of cells with wild-type VZV triggered phosphorylation of Akt, while infection with an ORF12 deletion mutant induced less phosphorylated Akt. The activation of Akt by ORF12 protein was associated with its binding to the p85 subunit of PI3K. Infection of cells with wild-type VZV resulted in increased levels of cyclin B1, cyclin D3, and phosphorylated glycogen synthase kinase 3β (GSK-3β), while infection with the ORF12 deletion mutant induced lower levels of these proteins. Wild-type VZV infection reduced the G1 phase cell population and increased the M phase cell population, while infection with the ORF12 deletion mutant had a reduced effect on the G1 and M phase populations. Inhibition of Akt activity with reduced the G1 and M phase differences observed in cells infected with wild-type and ORF12 mutant viruses. In conclusion, we have found that the VZV ORF12 protein activates the PI3K/Akt pathway to regulate cell cycle progression. Since VZV replicates in both dividing (e.g., keratinocytes) and nondividing (neurons) cells, the ability of the VZV ORF12 protein to regulate the cell cycle is likely important for VZV replication in various cell types in the body. LY294002相似文献
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Xinxing Lu Qiuling Fan Li Xu Lin Li Yuan Yue Yanyan Xu Yan Su Dongcheng Zhang Lining Wang 《PloS one》2015,10(2)
ObjectiveTo investigate the effect of ursolic acid on autophagy mediated through the miRNA-21-targeted phosphoinositide 3 kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway in rat mesangial cells cultured under high glucose (HG) conditions.MethodsRat glomerular mesangial cells were cultured under normal glucose, HG, HG with the PI3K inhibitor or HG with ursolic acid conditions. Cell proliferation and hypertrophy were assayed using an MTT assay and the ratio of total protein to cell number, respectively. The miRNA-21 expression was detected using RT-qPCR. The expression of phosphatase and tensin homolog (PTEN)/AKT/mTOR signaling signatures, autophagy-associated protein and collagen I was detected by western blotting and RT-qPCR. Autophagosomes were observed using electron microscopy.ResultsCompared with mesangial cells cultured under normal glucose conditions, the cells exposed to HG showed up-regulated miRNA-21 expression, down-regulated PTEN protein and mRNA expression, up-regulated p85PI3K, pAkt, pmTOR, p62/SQSTMI, and collagen I expression and down-regulated LC3II expression. Ursolic acid and LY294002 inhibited HG-induced mesangial cell hypertrophy and proliferation, down-regulated p85PI3K, pAkt, pmTOR, p62/SQSTMI, and collagen I expression and up-regulated LC3II expression. However, LY294002 did not affect the expression of miRNA-21 and PTEN. Ursolic acid down-regulated miRNA-21 expression and up-regulated PTEN protein and mRNA expression.ConclusionsUrsolic acid inhibits the glucose-induced up-regulation of mesangial cell miRNA-21 expression, up-regulates PTEN expression, inhibits the activation of PI3K/Akt/mTOR signaling pathway, and enhances autophagy to reduce the accumulation of the extracellular matrix and ameliorate cell hypertrophy and proliferation. LY294002相似文献
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Na Liu Min Lu Xiao Ming Feng Feng Xia Ma Zhi Hong Fang Xue Mei Tian Qian Ren Lei Zhang Bin Liu Ping Ping Huang Lin Liu Zhong Chao Han 《Journal of cellular biochemistry》2009,106(6):1041-1047
PI3K signaling pathway plays a significant role in embryonic stem cells (ES cells) self‐renewal. Overexpression of Nanog maintains mouse ES cells pluripotency independent of leukemia inhibitory factor (LIF). However, little is known about the effect of PI3K signaling pathway on ES cells with Nanog overexpression. Our experiments aimed to explore the relationship between PI3K signaling pathway and Nanog expression in ES cells. We observed the effect of LY294002, a specific inhibitor of PI3K pathway, on wild‐type J1 cells and Nanog overexpressing (Ex‐Nanog) J1 cells in the presence or absence of LIF. With LY294002 treatment, both of them lost their ES features even in the presence of LIF. But the differentiation induced by LY294002 on Ex‐Nanog J1 cells was slighter lower than that on wild‐type J1 cells. These results indicate that inhibition of PI3K pathway induces mouse ES cells differentiation. Exogenous Nanog sustains mouse ES cells pluripotency independent of LIF, and alleviates the differentiation induced by LY294002. But it is insufficient to totally reverse the differentiation. J. Cell. Biochem. 106: 1041–1047, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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Hai‐Yang Wang Ye Yao Qing‐Feng Sun Zong‐Hong Liu Si‐Qi Liu Jun‐Li Zhuang Yun‐Peng Wang Hong‐Yu Liu 《Journal of cellular and molecular medicine》2017,21(8):1482-1491
This study aimed to investigate the role of miR‐138 in human coronary artery endothelial cell (HCAEC) injury and inflammatory response and the involvement of the PI3K/Akt/eNOS signalling pathway. Oxidized low‐density lipoprotein (OX‐LDL)‐induced HCAEC injury models were established and assigned to blank, miR‐138 mimic, miR‐138 inhibitor, LY294002 (an inhibitor of the PI3K/Akt/eNOS pathway), miR‐138 inhibitor + LY294002 and negative control (NC) groups. qRT‐PCR and Western blotting were performed to detect the miR‐138, PI3K, Akt and eNOS levels and the protein expressions of PI3K, Akt, eNOS, p‐Akt, p‐eNOS, Bcl‐2, Bax and caspase‐3. ELISAs were employed to measure the expressions of TNF‐α, IL‐4, IL‐6, IL‐8, IL‐10 and nitric oxide (NO) and the activities of lactate dehydrogenase (LDH) and eNOS. MTT and flow cytometry were performed to assess the proliferation and apoptosis of HCAECs. Compared to the blank group, PI3K, Akt and eNOS were down‐regulated in the miR‐138 mimic and LY294002 groups but were up‐regulated in the miR‐138 inhibitor group. The miR‐138 mimic and LY294002 groups showed decreased concentrations of TNF‐α, IL‐6, IL‐8 and NO and reduced activities of LDH and eNOS, while opposite trends were observed in the miR‐138 inhibitor group. The concentrations of IL‐4 and IL‐10 increased in the miR‐138 mimic and LY294002 groups but decreased in the miR‐138 inhibitor group. The miR‐138 mimic and LY294002 groups had significantly decreased cell proliferation and increased cell apoptosis compared to the blank group. These findings indicate that up‐regulation of miR‐138 alleviates HCAEC injury and inflammatory response by inhibiting the PI3K/Akt/eNOS signalling pathway. 相似文献
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《Free radical research》2013,47(9):1147-1155
AbstractBackground. Insulin protects cardiomyocytes from reactive oxygen species (ROS)-induced apoptosis after ischemic/reperfusion injury, but the mechanism is not clear. This study investigated the protective mechanism of insulin in preventing cardiomyocyte apoptosis from ROS injury. Methods. Rat cardiomyoblast H9c2 cells were treated with hydrogen peroxide (H2O2) or insulin at various concentrations for various periods of time, or with insulin and H2O2 for various periods of time. Cell viability was measured by the methylthiazolydiphenyl-tetrazolium bromide method. Cellular miR-210 levels were quantified using real-time RT-PCR. MiR-210 expression was also manipulated through lentivirus-mediated transfection. LY294002 was used to investigate involvement of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. Results. The percentage of viable cells was significantly and inversely associated with H2O2 concentration, an effect that was seemingly attenuated by insulin pretreatment. Treatments with H2O2 or insulin were associated with a significant increase in miR-210 levels. Manipulation of miR-210 expression by gene transfection showed that miR-210 could attenuate H2O2-induced cellular injury. Inhibition of the PI3K/Akt pathway by the Akt inhibitor LY294002 was associated with a decrease in miR-210 expression. Conclusion. Insulin stimulated the expression of miR-210 through the PI3K/Akt pathway, resulting in a protective effect against cardiomyocyte injury that had been induced by H2O2/oxygen species. Our results provide novel evidence regarding the mechanism underlying the protective effect of insulin. 相似文献
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为研究臭椿酮(Ailanthone,AIL)诱导人黑色素瘤A375细胞凋亡的作用及作用机制,以人黑色素瘤A375细胞为研究对象,采用MTT法测定AIL对人黑色素瘤A375细胞生长增殖的抑制作用。用倒置相差显微镜观察AIL对A375细胞形态的影响,用荧光倒置显微镜观察Hoechst33258染色后AIL对A375细胞核的影响,用AnnexinV-FITC/PI双染法检测AIL诱导A375细胞凋亡的作用,用分光光度法检测caspase-3和caspase-9的活性,Westernblot检测p-PI3Kβ(Ser1070),PI3Kβ,p-Akt(Ser473)和Akt蛋白表达水平的变化,接着用PI3K抑制剂LY294002进行干预,进一步验证AIL对PI3K/Akt信号通路及细胞凋亡的影响。实验结果表明,AIL能够明显抑制A375细胞增殖,使A375细胞数目变少、附着力和透光性减弱,AIL能够诱导A375细胞凋亡,使其细胞核染色质发生固缩并呈现高亮,且使A375细胞早期及晚期凋亡率均增加,AIL作用后能够使caspase-3和caspase-9活性增加,AIL能够抑制PI3K和Akt蛋白磷酸化,从而使PI3K/Akt信号通路失活。较AIL单独作用,AIL和LY294002共同作用后对PI3K和Akt蛋白磷酸化的抑制作用增强且诱导凋亡作用增加,进一步说明AIL通过失活PI3K/Akt信号通路来诱导A375细胞凋亡。 相似文献
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Ding-Yu Lee Yi-Shuan J. Li Shun-Fu Chang Jing Zhou Hui-Min Ho Jeng-Jiann Chiu Shu Chien 《The Journal of biological chemistry》2010,285(1):30-42
Interstitial flow in and around bone tissue is oscillatory in nature and affects the mechanical microenvironment for bone cell growth and formation. We investigated the role of oscillatory shear stress (OSS) in modulating the proliferation of human osteoblast-like MG63 cells and its underlying mechanisms. Application of OSS (0.5 ± 4 dynes/cm2) to MG63 cells induced sustained activation of phosphatidylinositol 3-kinase (PI3K)/Akt/mTOR/p70S6K (p70S6 kinase) signaling cascades and hence cell proliferation, which was accompanied by increased expression of cyclins A and D1, cyclin-dependent protein kinases-2, -4, and -6, and bone formation-related genes (c-fos, Egr-1, and Cox-2) and decreased expression of p21CIP1 and p27KIP1. OSS-induced activation of PI3K/Akt/mTOR/p70S6K and cell proliferation were inhibited by specific antibodies or small interference RNAs of αvβ3 and β1 integrins and by dominant-negative mutants of Shc (Shc-SH2) and focal adhesion kinase (FAK) (FAK(F397Y)). Co-immunoprecipitation assay showed that OSS induces sustained increases in association of Shc and FAK with αvβ3 and β1 integrins and PI3K subunit p85, which were abolished by transfecting the cells with FAK(F397Y) or Shc-SH2. OSS also induced sustained activation of ERK, which was inhibited by the specific PI3K inhibitor and was required for OSS-induced activation of mTOR/p70S6K and proliferation in MG63 cells. Our findings provide insights into the mechanisms by which OSS induces osteoblast-like cell proliferation through activation of αvβ3 and β1 integrins and synergistic interactions of FAK and Shc with PI3K, leading to the modulation of downstream ERK and Akt/mTOR/p70S6K pathways. LY294002相似文献
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Wenlei Bao Yanfeng Wang Yuting Fu Xiaoyang Jia Jiaxin Li Nyamtsengel Vangan Lili Bao Huifang Hao Zhigang Wang 《PloS one》2015,10(5)
Bacterial flagellin triggers inflammatory responses. Phosphoinositide 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) regulate the production of pro- and anti-inflammatory cytokines that are induced by extrinsic antigens, but the function of mTORC1 in flagellin-induced inflammatory response is unknown. The purpose of this study was to examine the role and the mechanism of PI3K/Akt/mTOR pathway in flagellin-induced cytokine expression in mouse macrophages. We observed that flagellin upregulated TNF-α time- and dose-dependently. Flagellin stimulated rapid (<15 min) PI3K/Akt/mTOR phosphorylation that was mediated by TLR5. Inhibition of PI3K with and wortmannin, and of mTORC1 with rapamycin decreased flagellin-induced TNF-α and IL-6 expression and cell proliferation. The activation of NF-κB p65 and STAT3 was regulated by mTORC1 via degradation of IκBα and phosphorylation of STAT3 in response to flagellin, respectively. Thus, the PI3K/Akt/mTORC1 pathway regulates the innate immune response to bacterial flagellin. Rapamycin is potential therapy that can regulate host defense against pathogenic infections. LY294002相似文献