Loss of monopolar spindle-binding protein 3B expression promotes colorectal cancer malignant behaviors by activation of target of rapamycin kinase/autophagy signaling

BACKGROUND Monopolar spindle-binding protein 3B(MOB3B)functions as a signal transducer and altered MOB3B expression is associated with the development of human cancers.AIM To investigate the role of MOB3B in colorectal cancer(CRC).METHODS This study collected 102 CRC tissue samples for immunohistochemical detection of MOB3B expression for association with CRC prognosis.After overexpression and knockdown of MOB3B expression were induced in CRC cell lines,changes in cell viability,migration,invasion,and gene expression were assayed.Tumor cell autophagy was detected using transmission electron microscopy,while nude mouse xenograft experiments were performed to confirm the in-vitro results.RESULTS MOB3B expression was reduced in CRC vs normal tissues and loss of MOB3B expression was associated with poor CRC prognosis.Overexpression of MOB3B protein in vitro attenuated the cell viability as well as the migration and invasion capacities of CRC cells,whereas knockdown of MOB3B expression had the opposite effects in CRC cells.At the molecular level,microtubule-associated protein light chain 3 II/I expression was elevated,whereas the expression of matrix metalloproteinase(MMP)2,MMP9,sequestosome 1,and phosphorylated mechanistic target of rapamycin kinase(mTOR)was downregulated in MOB3B-overexpressing RKO cells.In contrast,the opposite results were observed in tumor cells with MOB3B knockdown.The nude mouse data confirmed these in-vitro findings,i.e.,MOB3B expression suppressed CRC cell xenograft growth,whereas knockdown of MOB3B expression promoted the growth of CRC cell xenografts.CONCLUSION Loss of MOB3B expression promotes CRC development and malignant behaviors,suggesting a potential tumor suppressive role of MOB3B in CRC by inhibition of mTOR/autophagy signaling.

Cytotoxicity of nonylphenol on spermatogonial stem cells via phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin pathway

BACKGROUND With continuous advancement of industrial society,environmental pollution has become more and more serious.There has been an increase in infertility caused by environmental factors.Nonylphenol(NP)is a stable degradation product widely used in daily life and production and has been proven to affect male fertility.However,the underlying mechanisms therein are unclear.Thus,it is necessary to study the effect and mechanism of NP on spermatogonial stem cells(SSCs).AIM To investigate the cytotoxic effect of NP on SSCs via the phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/AKT/mTOR)pathway.METHODS SSCs were treated with NP at 0,10,20 or 30μmol.MTT assay was performed to evaluate the effect of NP on the proliferation of SSCs.Flow cytometry was conducted to measure SSC apoptosis.The expression of Bad,Bcl-2,cytochrome-c,pro-Caspase 9,SOX-2,OCT-4,Nanog,Nanos3,Stra8,Scp3,GFRα1,CD90,VASA,Nanos2,KIT,PLZF and PI3K/AKT/mTOR-related proteins was observed by western blot,and the mRNA expression of SOX-2,OCT-4 and Nanog was detected by quantitative reverse transcription polymerase chain reaction.RESULTS Compared with untreated cells(0μmol NP),SSCs treated with NP at all concentrations showed a decrease in cell proliferation and expression of Bcl-2,Nanog,OCT-4,SOX-2,Nanos3,Stra8,Scp3,GFRα1,CD90,VASA,Nanos2,KIT,and PLZF(P<0.05),whereas the expression of Bad,cytochrome-c,and pro-Caspase 9 increased significantly(P<0.05).We further examined the PI3K/AKT/mTOR pathway and found that the phosphorylation of PI3K,AKT,mTORC1,and S6K was significantly decreased by NP at all concentrations compared to that in untreated SSCs(P<0.05).NP exerted the greatest effect at 30μmol among all NP concentrations.CONCLUSION NP attenuated the proliferation,differentiation and stemness maintenance of SSCs while promoting apoptosis and oxidative stress.The associated mechanism may be related to the PI3K/AKT/mTOR pathway.

Osteopontin promotes gastric cancer progression via phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway

BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors.Osteopontin(OPN)is thought to be closely related to the occurrence,metastasis and prognosis of many types of tumors.AIM To investigate the effects of OPN on the proliferation,invasion and migration of GC cells and its possible mechanism.METHODS The mRNA and protein expression of OPN in the GC cells were analyzed by realtime quantitative-reverse transcription polymerase chain reaction and western blotting,and observe the effect of varying degree expression OPN on the proliferation and other behaviors of GC.Next,the effects of OPN knockdown on GC cells migration and invasion were examined.The short hairpin RNA(shRNA)and negative control shRNA targeting OPN-shRNA were transfected into the cells according to the manufacturer’s instructions.Non transfected cells were classified as control in the identical transfecting process.24 h after RNA transfection cell proliferation activity was detected by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide assay,and cell invasiveness and migration were detected by Trans well assay.Meanwhile,the expression of protein kinase B(AKT),matrix metalloproteinase 2(MMP-2)and vascular endothelial growth factor(VEGF)in the human GC cell lines was detected by reverse transcription polymerase chain reaction and western blotting.RESULTS The results of this study revealed that OPN mRNA and protein expression levels were highly expressed in SGC-7901 cells.OPN knockdown by specific shRNA noticeably reduced the capabilities of proliferation,invasion and migration of SGC-7901 cells.Moreover,in the experiments of investigating the underlying mechanism,results showed that OPN knockdown could down-regulated the expression of MMP-2 and VEGF,it also decreased the phosphorylation of AKT.Meanwhile,the protein expression levels of MMP-2,VEGF and phosphorylated AKT was noticeable lower than that in control group in the GC cells after they were added to phosphatidylinositol-3-kinase(PI3K)inhibitor(LY294002).CONCLUSION These results suggested that OPN though PI3K/AKT/mammalian target of rapamycin signal pathway to upregulate MMP-2 and VEGF expression,which contribute SGC-7901 cells to proliferation,invasion and migration.Thus,our results demonstrate that OPN may serve as a novel prognostic biomarkers as well as a potential therapeutic targets for GC.

Adenosine triphosphate promotes locomotor recovery after spinal cord injury by activating mammalian target of rapamycin pathway in rats

The mammalian target of rapamycin （mTOR） pathway plays an important role in neuronal growth, proliferation and differentiation. To better understand the role of mTOR pathway involved in the induction of spinal cord injury, rat models of spinal cord injury were established by modified Allen＇s stall method and interfered for 7 days by intraperitoneal administration of mTOR activator adenosine triphosphate and mTOR kinase inhibitor rapamycin. At 1-4 weeks after spinal cord injury induction, the Basso, Beattie and Bresnahan locomotor rating scale was used to evaluate rat locomotor function, and immunohistochemical staining and western blot analysis were used to detect the expression of nestin （neural stem cell marker）, neuronal nuclei （neuronal marker）, neuron specific enolase, neurofilament protein 200 （axonal marker）, glial fibrillary acidic protein （astrocyte marker）, Akt, mTOR and signal transduction and activator of transcription 3 （STAT3）. Results showed that adenosine triphosphate-mediated Akt/mTOR/STAT3 pathway increased endogenous neural stem cells, induced neurogenesis and axonal growth, inhibited excessive astrogliosis and improved the locomotor function of rats with spinal cord injury.

Neuroendocrine tumors resistant to mammalian target of rapamycin inhibitors:A difficult conversion from biology to the clinic

Deregulation of the phosphoinositide 3-kinase(PI3K)/protein kinase B(Akt)- mammalian target of rapamycin(m TOR) signaling pathway is one of the most commonlyinvolved pathways in tumorigenesis. It has also been reported as altered in neuroendocrine tumors(NETs). m TOR inhibitors used in clinical practice are derived from rapamycin,an anti-cancer agent also used as an immunosuppressor after organ transplantation. Everolimus and temsirolimus are the two rapamycin-derived m TOR inhibitors used in NETs. Notably everolimus has been approved in advanced progressive well/moderatelydifferentiated pancreatic NETs(p NETs). It inhibits specifically the m TORC1 subunit of m TOR,not interacting with m TORC2. Although everolimus produced a significant prolongation of progression-free survival a number of patients with p NETs do not benefit from the drug due to early or late progression. Two supposed mechanisms of resistance to m TOR inhibitors are Akt and PI3 K activation,by means of m TORC2 and insulin growth factor(IGF)- IGF receptor signaling,respectively. BEZ235 is a multi-targeted inhibitor binding to PI3 K,m TORC1 and m TORC2,therefore potentially turning off all the supposed molecular targets of resistance to everolimus. The two clinical trials designed in p NETs were stopped early due to unmet statistical endpoint and the global clinical development of BEZ235 was also halted. Tolerability of this drug was challenging and conditioned the feasibility of therapy. The BEZ experience is an example of the huge difference between the preclinical and clinical setting and prompts us to pay more attention to the phase Ⅰ step of clinical development and the design of phase Ⅱ clinical trials.

Influence of Phosphatidylinositol-3-Kinase/Protein Kinase B-Mammalian Target of Rapamycin Signaling Pathway on the Neuropathic Pain Complicated by Nucleoside Reverse Transcriptase Inhibitors for the Treatment of HIV Infection

Background： Nucleoside reverse transcriptase inhibitors （NRTIs） are the earliest and most commonly used anti-human immunodeficiency virus drugs and play an important role in high active antiretroviral therapy. However, NRTI drug therapy can cause peripheral neuropathic pain. In this study, we aimed to investigate the mechanisms ofrapamycin on the pain sensitization of model mice by in vivo experiments to explore the effect of mammalian target of rapamycin （mTOR） in the pathogenesis ofneuropathic pain caused by NRTIs. Methods： Male Kun Ming （KM） mice weighing 20-2 g were divided into control, 2 mg/kg rapamycin, 12 mg/kg stavudine, and CMC-Na groups. Drugs were orally administered to mice for 42 consecutive days. The von Frey filament detection and thermal pain tests were conducted on day 7, 14, 21, 28, 35, and 42 after drug administration. After the last behavioral tests, immunohistochemistry and western blotting assay were used for the measurement of mTOR and other biomarkers. Multivariate analysis of variance was used. Results： The beneficial effects ofrapamycin on neuropathic pain were attributed to a reduction in mammalian target of rapamycin sensitive complex 1 （mTORC1）-positive cells （70.80± 2.41 vs. 112.30 ± 5.66, F = 34.36, P 〈 0.01 ） and mTORC1 activity in the mouse spinal cord. Mechanistic studies revealed that Protein Kinase B （Akt）/mTOR signaling pathway blockade with rapamycin prevented the phosphorylation of mTORC1 in stavudine-intoxicated mice （0.72 ± 0.04 vs. 0.86 ± 0.03, F=4.24, P = 0.045）, as well as decreased the expression of phospho-pTOS6K （0.47 ± 0.01 vs. 0.68 ± 0.03, F=6.01, P = 0.022） and phospho-4EBP1 （0.90 ± 0.04 vs. 0.94 ± 0.06, F= 0.28, P = 0.646）. Conclusions： Taken together, these results suggest that stavudine elevates the expression and activity of mTORC1 in the spinal cord through activating the Akt/mTOR signaling pathway. The data also provide evidence that rapamycin might be useful for the treatment of peripheral neuropathic pain.

Amino acids regulate energy utilization through mammalian target of rapamycin complex 1 and adenosine monophosphate activated protein kinase pathway in porcine enterocytes

As major fuels for the small intestinal mucosa,dietary amino acids(AA)are catabolized in the mitochondria and serve as sources of energy production.The present study was conducted to investigate AA metabolism that supply cell energy and the underlying signaling pathways in porcine enterocytes.Intestinal porcine epithelial cells(IPEC-J2)were treated with different concentrations of AA,inhibitor,or agonist of mammalian target of rapamycin complex 1(mTORCl)and adenosine monophosphate activated protein kinase(AMPK),and mitochondrial respiration was monitored.The results showed that AA treatments resulted in enhanced mitochondrial respiration,increased intracellular content of pyruvic acid and lactic acid,and increased hormone-sensitive lipase mRNA expression.Meanwhile,decreased citrate synthase,isocitrate dehydrogenase alpha,and carnitine palmitoyltransferase 1 mRNA expression were also observed.We found that AA treatments increased the protein levels of phosphorylated mammalian target of rapamycin(p-mTOR),phosphorylated-p70 ribosomal protein S6 kinase,and phosphorylated-4 E-binding protein 1.What is more,the protein levels of phosphorylated AMPKα(pAMPKa)and nicotinamide adenine dinucleotide(NAD)-dependent protein deacetylase sirtuin-1(SIRT1)were decreased by AA treatments in a time depending manner.Mitochondrial bioenergetics and the production of tricarboxylic acid cycle intermediates were decreased upon inhibition of mTORCl or AMPK.Moreover,AMPK activation could up-regulate the mRNA expressions of inhibitor of nuclear factor kappa-B kinase subunit beta(Ikbk(3),integrin-linked protein kinase(ILK),unconventional myosin-Ic(Myolc),ribosomal protein S6 kinase beta-2(RPS6 Kβ2),and vascular endothelial growth factor(VEGF)-β,which are downstream effectors of mammalian target of rapamycin(mTOR).The mRNA expressions of phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit delta isoform(PIK3 CD)and5’-AMP-activated protein kinase subunit gamma-1(PRKAG1),which are upstream regulators of mTOR,were also up-regulated by AMPK activation.On the other hand,AMPK activation also down-regulated FK506-binding protein 1 A(FKBP1 A),serine/threonine-protein phosphatase 2 A 55 kDa regulatory subunit B beta isoform,phosphatase and tensin homolog(PTEN),and unc-51 like autophagy activating kinase 1(Ulkl),which are up-stream regulators of mTORCl.Taken together,these data indicated that AA regulated cellular energy metabolism through mTOR and AMPK pathway in porcine enterocytes.These results demonstrated interactions of AMPK and mTORCl pathways in AA catabolism and energy metabolism in intestinal mucosa cells of piglets,and also provided reference for using AA to remedy human intestinal diseases.

TopoisomeraseⅡalpha promotes gallbladder cancer proliferation and metastasis through activating phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway

Background:TopoisomeraseⅡalpha(TOP2A)has been reported to play a crucial role in the tumorigenesis of various cancer types.However,the biological role of TOP2A in gallbladder cancer(GBC)remains unknown.The current study aimed to explore the function and potential mechanism of TOP2A in GBC.Methods:Based on Gene Expression Profiling Interactive Analysis data,we found TOP2A was significantly up-regulated in GBC tissues and resulting in shorter overall survival.Quantitative real-time polymerase chain reaction and immunohistochemistry were conducted to detect the expression of TOP2A in 45 pairs of GBC tissues and adjacent non-tumor tissues.In vitro,cell proliferation,migration,and invasion ability were examined by cell counting kit-8 and transwell assay,respectively.Epithelial-mesenchymal transition(EMT)related and phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/Akt/mTOR)pathway-related markers were measured by Western blotting.Xenograft model assay was performed to evaluate the effect of TOP2A in vivo.Results:TOP2A was found up-regulated in GBC(tumor vs.normal,12.62 vs.0.34)and correlated with the late tumor node metastasis stage(P=0.0032),present of lymph node metastasis(P=0.0273),and poor prognosis in GBC patients(log-rank P=0.028).In vitro and in vivo assays showed that knockdown of TOP2A notably inhibited cell proliferation,migration,invasion,EMT process,and tumor growth in GBC.In addition,TOP2A down-regulation significantly decreased the protein levels of phosphor(p)-PI3K,p-Akt,and p-mTOR.Conclusion:Our study demonstrates that TOP2A was overexpressed in GBC and associated with poor prognosis in GBC patients.TOP2A promotes GBC cell proliferation,migration,invasion,EMT process,and tumor growth through activating PI3K/Akt/mTOR signaling pathway,and may serve as a novel prognostic biomarker and therapeutic target for GBC.

LY294002和Rapamycin对柯萨奇病毒B3诱导的HeLa细胞Bim和Bax表达的调控作用

目的探讨磷脂酰肌醇3激酶(PI3K)和哺乳动物雷帕霉素靶蛋白(mTOR)信号通路在柯萨奇病毒B3(CVB3)诱导细胞凋亡中的作用。方法体外培养的HeLa细胞通过CVB3感染建立病毒性心肌炎模型,根据细胞毒力实验筛选10 nmol/L的雷帕霉素(Rapamycin)和25μmol/L的PI3K抑制剂(LY294002)干预CVB3感染的HeLa细胞,采用RT-PCR和Western blot免疫印迹法检测Bim和Bax的mRNA及蛋白质表达。结果感染CVB3 12和24 h后,LY294002和Rapamycin促进CVB3诱导的HeLa细胞产生CPE。与Sham组比较,CVB3可以诱导Bim mRNA和蛋白的表达降低(P<0.05),Bax mRNA表达早期降低而蛋白表达逐渐增强,而与对照组比较,LY294002和Rapamycin可以使Bim mRNA和蛋白的表达增强(P<0.05);LY294002使Bax mRNA表达逐渐减弱而蛋白表达逐渐增强,Rapamycin则使Bax蛋白表达随感染时间延长呈3 h增强(P<0.05),6和12h减弱,24 h增强的动态改变(P<0.05)。结论 PI3K和mTOR信号通路可能通过调控Bim和Bax的表达,在CVB3感染诱导的VMC中扮演重要角色。

Human neural stem cell-derived extracellular vesicles protect against ischemic stroke by activating the PI3K/AKT/mTOR pathway

Human neural stem cell-derived extracellular vesicles exhibit analogous functions to their parental cells,and can thus be used as substitutes for stem cells in stem cell therapy,thereby mitigating the risks of stem cell therapy and advancing the frontiers of stem cell-derived treatments.This lays a foundation for the development of potentially potent new treatment modalities for ischemic stroke.However,the precise mechanisms underlying the efficacy and safety of human neural stem cell-derived extracellular vesicles remain unclear,presenting challenges for clinical translation.To promote the translation of therapy based on human neural stem cell-derived extracellular vesicles from the bench to the bedside,we conducted a comprehensive preclinical study to evaluate the efficacy and safety of human neural stem cell-derived extracellular vesicles in the treatment of ischemic stroke.We found that administration of human neural stem cell-derived extracellular vesicles to an ischemic stroke rat model reduced the volume of cerebral infarction and promoted functional recovery by alleviating neuronal apoptosis.The human neural stem cell-derived extracellular vesicles reduced neuronal apoptosis by enhancing phosphorylation of phosphoinositide 3-kinase,mammalian target of rapamycin,and protein kinase B,and these effects were reversed by treatment with a phosphoinositide 3-kinase inhibitor.These findings suggest that human neural stem cell-derived extracellular vesicles play a neuroprotective role in ischemic stroke through activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway.Finally,we showed that human neural stem cell-derived extracellular vesicles have a good in vivo safety profile.Therefore,human neural stem cell-derived extracellular vesicles are a promising potential agent for the treatment of ischemic stroke.

淫羊藿苷调控mTOR/Akt/CREB通路对高糖诱导的足细胞自噬及凋亡的影响

目的 探讨淫羊藿苷对高糖诱导的足细胞自噬、凋亡及哺乳动物雷帕霉素靶蛋白(mTOR)/丝氨酸苏氨酸蛋白激酶(Akt)/环磷酸腺苷反应元件结合蛋白(CREB)通路的影响。方法 将小鼠足细胞MPC5分为5组:正常对照组(5.5 mmol·L^(-1)葡萄糖)、高糖组(30 mmol·L^(-1)葡萄糖)、淫羊藿苷组(30 mmol·L^(-1)葡萄糖+5μmol·L^(-1)淫羊藿苷)、GDC-0349组(30 mmol·L^(-1)葡萄糖+50μmol·L^(-1)GDC-0349)、淫羊藿苷+GDC-0349组(30 mmol·L^(-1)葡萄糖+5μmol·L^(-1)淫羊藿苷+50μmol·L^(-1)GDC-0349)。培养48 h后,噻唑蓝法检测MPC5细胞活力;吖啶橙染色观察MPC5细胞自噬情况;流式细胞术检测MPC5细胞凋亡;蛋白印迹法检测MPC5细胞自噬[微管相关蛋白1轻链3(LC3)Ⅱ、LC3Ⅰ、自噬相关蛋白(Beclin-1)]、凋亡[Bcl-2相关X蛋白(Bax)、B淋巴细胞瘤-2(Bcl-2)]和mTOR/Akt/CREB通路相关蛋白的表达。结果 与正常对照组比较,高糖组MPC5细胞活力、Bcl-2、磷酸化mTOR(p-mTOR)/mTOR、磷酸化Akt(p-Akt)/Akt、磷酸化CREB(p-CREB)/CREB蛋白表达水平显著降低(P<0.05),自噬能力增强,自噬体表现出橙色荧光,细胞凋亡率、LC3Ⅱ/LC3Ⅰ、Beclin-1、Bax蛋白表达水平显著升高(P<0.05)。与高糖组比较,淫羊藿苷组MPC5细胞活力、LC3Ⅱ/LC3Ⅰ、Beclin-1、Bcl-2、p-mTOR/mTOR、p-Akt/Akt、p-CREB/CREB蛋白表达水平显著升高,自噬能力进一步增强,自噬体数量增多,自噬体呈现出砖红色荧光(P<0.05),细胞凋亡率、Bax蛋白表达水平显著降低(P<0.05);GDC-0349组MPC5细胞活力、LC3Ⅱ/LC3Ⅰ、Beclin-1、Bcl-2、p-mTOR/mTOR、p-Akt/Akt、p-CREB/CREB蛋白表达水平显著降低,自噬能力减弱,自噬体数量减少,自噬体表现出橙色荧光(P<0.05),细胞凋亡率、Bax蛋白表达水平显著升高(P<0.05);淫羊藿苷+GDC-0349可逆转淫羊藿苷对高糖诱导MPC5细胞的作用效果(P<0.05)。结论 淫羊藿苷通过激活mTOR/Akt/CREB通路促进高糖诱导的足细胞自噬抑制细胞凋亡。

Targeting metastatic upper gastrointestinal adenocarcinomas

Upper gastrointestinal(GI)tumors,including adenocarcinoma of the esophagus,stomach,pancreas,and biliary tree,have traditionally been difficult to treat with cytotoxic chemotherapeutic agents.There has been little drug development success in treating these cancers over the last 20 years,perhaps a reflection of a combination of the aggressive biology of these tumors,the void in effective and specific drug development for these varied tumors,and the lack of properly designed,biologically-based clinical trials.Recently,so called“targeted agents”have risen to the forefront in the care of cancer patients and have made strong impacts in many areas of oncology,particularly gastrointestinal stromal tumors(GIST),colon,breast,and lung cancers.Unfortunately,slow progress has been made using such agents in upper GI tumors.However,more recently,trials in some tumor types have demonstrated gains in progression free survival and overall survival.In this review,we discuss the drugs and pathways that have been most successful in the treatment of upper GI tumors and present the relevant data supporting their use for each tumor site.Additionally,we will explore a few novel pathways that may prove effective in the treatment of upper GI malignancies in the near future.

下调HMGB2表达对肝癌LM3细胞上皮-间质转化的抑制作用及其AKT/mTOR信号通路机制

目的:探讨下调肝癌细胞中高迁移率族框蛋白2 (HMGB2)表达对肝癌细胞生物学行为及上皮-间质转化(EMT)进程的影响,并阐明其作用机制。方法:对数生长期的人肝癌LM3细胞分为阴性对照组和HMGB2 RNA干扰组(HMGB2 siRNA组),分别以Lipofectamin 2000为载体转染无关序列的RNA寡核苷酸(RNA oligo)和敲除HMGB2序列的RNA oligo。采用实时荧光定量PCR(RT-qPCR)法和Western blotting法检测2组细胞中HMGB2 mRNA和蛋白表达水平,分别采用细胞划痕实验和Transwell小室实验检测2组细胞的迁移和侵袭能力,采用Western blotting法检测2组细胞中E-钙黏蛋白(E-cadherin)、 N-钙黏蛋白(N-cadherin)、波形蛋白(Vimentin)和蛋白激酶B(AKT)/哺乳动物雷帕霉素靶蛋白(mTOR)通路相关蛋白表达水平。结果:与阴性对照组比较,HMGB2 siRNA组细胞中HMGB2 mRNA和蛋白表达水平均明显降低(P<0.05),HMGB2 siRNA组细胞划痕愈合率明显降低(P<0.01),侵袭细胞数明显减少(P<0.01),细胞中E-cadherin蛋白表达水平明显升高(P<0.01),N-cadherin、Vimentin、mTOR、AKT和磷酸化AKT (p-AKT)蛋白表达水平明显降低(P<0.05或P<0.01)。结论:下调HMGB2的表达可降低肝癌LM3细胞迁移和侵袭能力并抑制EMT,其作用机制可能与参与调节AKT/mTOR通路相关蛋白表达有关。

“Targeting” renal cell carcinoma patients with “targeted” agents: Are we there yet?

The rapid approval of several novel agents, targeting the vascular endothelial growth factor or mammalian target of rapamycin pathways(sunitinib, pazopanib, sorafenib, axitinib, bevacizumab, everolimus, temsirolimus) has given to metastatic renal cell carcinoma(m RCC) patients and their treating physicians many new and effective therapeutic options. The treatment paradigm for these patients is rapidly evolving, with future studies needed to defi ne the optimal sequencing of these new agents. Despite progresses, no validated biomarkers able to predict clinical outcome or useful to guide patient selection for treatment are currently available. Recent studies have suggested that some biomarkers, including cytokines, circulating proangio-genic factors, markers of hypoxia or targets of signaling pathways are potentially promising prognostic or predictive factors in m RCC. We present an overview of the most recent developments in identifying biomarkers for targeted therapies in advanced RCC.

栀子苷调节PI3K/AKT/mTOR信号通路在动脉粥样硬化形成过程中对Th17/Treg功能的影响

目的:观察栀子苷对载脂蛋白E缺乏(ApoE^(-/-))小鼠Th17/调节性T(Treg)细胞失衡的影响及其作用机制。方法:将50只纯合子ApoE^(-/-)雌性小鼠随机分为对照组、模型组和栀子苷低剂量组、栀子苷中剂量组、栀子苷高剂量组。对照组小鼠喂养普通饲料,模型组和栀子苷组小鼠喂养高脂饲料。从第8周开始,栀子苷各剂量组每日灌胃栀子苷(25、50、100 mg/kg),连续8周。试验结束时,采用油红O染色评估主动脉及其根部动脉粥样硬化(AS)病变面积比。采用定量逆转录聚合酶链式反应(RT-PCR)分析主动脉组织肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-17A和IL-10 mRNA表达;采用流式细胞仪分析脾脏中Th17和Treg细胞百分比;蛋白免疫印迹法(Western Blot)检测主动脉组织磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路相关蛋白表达。结果:油红O染色病变显示,栀子苷中剂量组、栀子苷高剂量组病变百分比低于模型组(P<0.05)。与对照组比较,模型组主动脉TNF-α、IL-6和IL-17A mRNA表达水平升高(P<0.05);栀子苷各剂量组主动脉TNF-α、IL-6和IL-17A mRNA表达水平降低(P<0.05)。与对照组比较,模型组主动脉抗炎细胞因子IL-10 mRNA表达水平降低(P<0.05);栀子苷各剂量组主动脉抗炎细胞因子IL-10 mRNA表达水平升高(P<0.05)。与对照组比较,模型组小鼠脾脏中Th17细胞百分比升高,Treg细胞百分比降低(P<0.05)。栀子苷处理恢复了AS小鼠Th17和Treg细胞的平衡。栀子苷抑制PI3K的表达及AKT和mTOR的磷酸化,MHY1485(mTOR活化剂)减弱了栀子苷对T细胞分化的影响。结论:栀子苷抗AS作用机制可能与抑制PI3K/AKT/mTOR信号引起的Treg细胞增多和Th17细胞减少有关。

鳖甲煎丸对肝癌大鼠黏着斑激酶/雷帕霉素靶蛋白通路的影响

目的:探讨鳖甲煎丸对肝癌模型大鼠肝组织病理特征及FAK/mTORC1通路的影响。方法:HepG2(1×10^(7))细胞注射于大鼠右腋皮下,建立肝癌模型,分为模型组、5-氟尿嘧啶组、鳖甲煎丸低剂量组、鳖甲煎丸高剂量组,另设正常组。各药物组给予相应药物灌胃,持续给药4周,正常组、模型组给予等体积的0.9%氯化钠溶液。实验结束后,测定肝癌组织重量、肝癌组织体积、肝癌组织抑瘤率、肝癌FAK、mTORC1水平、肝癌VEGFR-2、VEGF、IL-4、IL-8、TNF-α蛋白水平。结果:与正常组比较,模型组肝癌组织重量、肝癌组织体积、肝癌组织抑瘤率、VEGFR-2、VEGF、IL-4、IL-8、TNF-α蛋白、肝癌FAK、mTORC1 mRNA和蛋白表达升高(均P<0.05)。与模型组比较,5-氟尿嘧啶组、鳖甲煎丸低剂量组、鳖甲煎丸高剂量组肝癌组织重量、肝癌组织体积、肝癌组织抑瘤率、VEGFR-2、VEGF、IL-4、IL-8、TNF-α蛋白、肝癌FAK、mTORC1 mRNA和蛋白表达降低(均P<0.05)。鳖甲煎丸高剂量组肝癌组织重量、肝癌组织体积、肝癌组织抑瘤率、VEGFR-2、VEGF、IL-4、IL-8、TNF-α蛋白、肝癌FAK、mTORC1 mRNA和蛋白表达低于鳖甲煎丸低剂量组(均P<0.05)。结论:鳖甲煎丸对大鼠肝癌具有明显抑制作用,能减轻大鼠肝癌所致的病理损伤,其机制可能与鳖甲煎丸抑制肝癌FAK、mTORC1表达,诱导肝癌细胞凋亡,降低炎症反应有关。

基于PI3K/Akt/mTOR 通路探究七氟醚麻醉对大鼠神经细胞凋亡的影响

目的探讨七氟醚麻醉对大鼠认知功能及神经细胞凋亡的影响。方法取96只大鼠,随机分为对照组(吸入2 L·min^(−1)氧气)、七氟醚低浓度组(吸入体积分数为1%的七氟醚+2 L·min^(−1)氧气)、七氟醚中浓度组(吸入体积分数为2%的七氟醚+2 L·min^(−1)氧气)、七氟醚高浓度组(吸入体积分数为4%的七氟醚+2 L·min^(−1)氧气),持续吸入6 h。用Morris水迷宫实验观察各组大鼠认知能力,用HE染色观察海马组织学形态,用酶联免疫吸附试验(enzyme linked immunosorbent assay,ELISA)测定海马组织中枢神经特异性蛋白(soluble protein 100β,S-100β)、神经元特异性烯醇化酶(neuron-specific enolase,NSE)、白细胞介素-1β(interleukin-1β,IL-1β)和肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平,流式细胞术测定神经细胞凋亡情况,蛋白印迹法(Western blotting)测定海马组织B淋巴细胞瘤-2(B-cell lymphoma-2,Bcl-2)、Bcl-2相关X蛋白(Bcl2-associated X protein,Bax)、磷酸化磷脂酰肌醇3-激酶(phosphorylated phosphatidylinositol 3-kinase,p-PI3K)、磷酸化丝氨酸/苏氨酸激酶(phosphorylated serine/threonine kinase,p-Akt)和磷酸化哺乳动物雷帕霉素靶蛋白(phosphorylated mammalian target of rapamycin,p-mTOR)的水平。结果HE染色结果表明,对照组海马组织神经细胞结构正常,排列紧密,七氟醚各浓度组大鼠海马组织神经细胞减少,排列紊乱,分布不均匀。与对照组比较,七氟醚各浓度组大鼠逃避潜伏期时间,S100-β、NSE、IL-1β、TNF-α水平,Bax蛋白水平和神经细胞凋亡率均升高,穿越平台次数,平台停留时间,Bcl-2、p-PI3K、p-Akt和p-mTOR蛋白水平均降低(P<0.05);七氟醚各浓度组诸项指数水平变化规律相同,并呈剂量依赖性(P<0.05)。结论七氟醚麻醉可诱导大鼠神经细胞凋亡,使大鼠认知能力衰退,其可能与调控PI3K/Akt/mTOR信号通路有关。

青藤碱调节AMPK/mTOR/ULK1信号通路对IL-1β诱导的关节软骨细胞自噬和凋亡的影响

目的探讨青藤碱(SN)调节单磷酸腺苷活化蛋白激酶(AMPK)/雷帕霉素靶蛋白(mTOR)/UNC-51样激酶1(ULK1)信号通路对白介素-1β(IL-1β)诱导的关节软骨细胞自噬和凋亡的影响。方法将关节软骨细胞分为Control组(正常培养)、IL-1β组(10μg/L的IL-1β诱导12 h)、L-SN、M-SN、H-SN组(在IL-1β诱导的基础上添加25、50、100μmol/L的SN)、SN+Compound C组(在H-SN组的基础上添加10μmol/L AMPK抑制剂Compound C)。MTT法、透射电子显微镜(TEM)、流式细胞仪分别检测SN对各组关节软骨细胞增殖、自噬、凋亡的影响;ELISA试剂盒检测各组细胞中COX-2、TNF-α、MMP-3、MMP-13的表达;蛋白印迹实验(WB)检测各组细胞中p-AMPK、AMPK、p-mTOR、mTOR、p-ULK1、ULK1蛋白水平。结果与Control组比较,IL-1β组关节软骨细胞的A 490值、p-AMPK/AMPK、p-ULK1/ULK1蛋白水平降低,自噬空泡数、凋亡率、COX-2、TNF-α、MMP-3、MMP-13、p-mTOR/mTOR蛋白水平升高(P<0.05);与IL-1β组比较,L-SN组、M-SN组、H-SN组A 490值、自噬空泡数、p-AMPK/AMPK、p-ULK1/ULK1蛋白水平升高,凋亡率、COX-2、TNF-α、MMP-3、MMP-13、p-mTOR/mTOR蛋白水平降低(P<0.05);与H-SN组比较,SN+Compound C组A 490值、自噬空泡数、p-AMPK/AMPK、p-ULK1/ULK1蛋白水平降低,凋亡率、COX-2、TNF-α、MMP-3、MMP-13、p-mTOR/mTOR蛋白水平升高(P<0.05)。结论SN可以通过促进IL-1β诱导的关节软骨细胞自噬,抑制细胞凋亡,其机制可能是通过激活AMPK/mTOR/ULK1信号通路实现的。

基于“肾脑相济”理论探讨艾灸对阿尔茨海默病大鼠海马AMPK/mTOR信号通路的影响

目的观察艾灸对阿尔茨海默病(Alzheimer’s disease,AD)大鼠腺苷酸活化蛋白激酶(adenosine 5-monophosphate activated protein kinase,AMPK)/雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)信号通路相关递质表达的影响,探讨艾灸治疗AD的作用机制。方法将SD大鼠按照随机数字表法分为正常组8只、模型组32只,采取侧脑室注射β淀粉样蛋白(amyloidβ-protein,Aβ)_(25-35)的方法建立大鼠AD模型。将模型复制成功的大鼠随机分为模型组、药物组、艾灸组,每组8只。艾灸组大鼠用艾条灸“百会”“肾俞”“三阴交”,每次15 min,同时按3 mg/kg灌胃蒸馏水;药物组大鼠按3 mg/kg灌胃盐酸多奈哌齐;对照组及模型组大鼠按3 mg/kg灌胃蒸馏水。采用Morris水迷宫法检测大鼠行为学表现,苏木精—伊红染色法观察大鼠海马病理组织改变,Western blot法检测大鼠海马磷酸化雷帕霉素靶蛋白(phosphorylated mammalian target of rapamycin,p-mTOR)、核糖体蛋白S6激酶(ribosomal protein S6 kinase p70,P70S6K)、自噬相关基因5(autophagy-related gene 5,ATG5)、磷酸化腺苷酸活化蛋白激酶(phosphorylated adenosine 5-monophosphate activated protein kinase,p-AMPK)、微管相关蛋白1轻链3B(microtubule associated protein light chain 3B,LC3B)-Ⅱ/LC3B-Ⅰ的表达水平。结果苏木精—伊红染色结果表明,模型组海马神经元萎缩明显,与模型组比较,药物组和艾灸组海马神经元形态及分化程度均有明显改善。与正常组比较,模型组大鼠的逃避潜伏期显著延长(P<0.05),p-mTOR及P70S6K表达水平均显著升高(P<0.05),ATG5、LC3B-Ⅱ/LC3B-Ⅰ、p-AMPK表达水平均显著降低(P<0.05)。与模型组比较,药物组和艾灸组大鼠的逃避潜伏期均显著缩短(P<0.05),p-mTOR及P70S6K表达水平均显著下降(P<0.05),ATG5、LC3B-Ⅱ/LC3B-Ⅰ、p-AMPK表达水平均显著上升(P<0.05)。与药物组比较,艾灸组大鼠逃避潜伏期显著缩短(P<0.05);p-mTOR及P70S6K表达水平显著降低(P<0.05),ATG5、LC3B-Ⅱ/LC3B-Ⅰ、p-AMPK表达水平均显著上升(P<0.05)。结论艾灸能够调控AMPK/mTOR信号通路,诱导细胞自噬,阻断脑内Aβ表达,从而改善认知功能。

针刺联合督灸治疗强直性脊柱炎的疗效观察

目的 观察针刺联合督灸治疗强直性脊柱炎的临床疗效及对AKT/PI3K/mTOR信号通络的影响。方法将96例强直性脊柱炎患者随机分为两组(观察组和对照组),每组48例。对照组口服美洛昔康治疗,观察组予针刺联合督灸治疗。观察两组治疗前后巴氏强直性脊柱炎病情评测指数(Bath ankylosing spondylitis disease activity index,BASDAI)和巴氏强直性脊柱炎活动能力量表(Bath ankylosing spondylitis functional index,BASFI)评分、血清炎性因子[核因子-κB(nuclear factor-κB,NK-κB)、巨噬细胞移动抑制因子(macrophage migration inhibitory factor,MIF)、CC趋化因子受体6(CC chemokine receptor 6,CCR6)和单核细胞趋化蛋白-4(monocyte chemokine protein-4,MCP-4)]水平、骨化相关蛋白[基质金属蛋白酶组织抑制剂-2(matrix metalloproteinase tissue inhibitor-2,TIMP-2)、高迁移率族蛋白B1(high mobility group protein box 1,HMGB1)、Dickkopf相关蛋白-1(dickkopf-related protein-1,DKK-1)和骨硬化蛋白(sclerostin,SOST)]水平以及AKT/PI3K/mTOR信号通路[蛋白激酶B(protein kinase B,AKT)、磷脂酰肌醇-3-激酶(phosphatidylinositol-3-kinase,PI3K)和雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)]水平的变化。比较两组临床疗效及不良反应发生情况。结果 观察组总有效率为97.9%,高于对照组的81.8%(P<0.05)。观察组治疗后、随访3个月及6个月BASDAI和BASFI评分均低于对照组(P<0.05)。观察组治疗后血清NK-κB、MIF、CCR6、MCP-4、TIMP-2、HMGB1、AKT、PI3K和mTOR水平均低于对照组(P<0.05),DKK-1和SOST水平高于对照组(P<0.05)。结论 针刺联合督灸可明显缓解强直性脊柱炎患者的临床症状,疗效优于口服美洛昔康治疗,并可调节AKT/PI3K/mTOR信号通络的表达。