Spi1 regulates the microglial/macrophage inflammatory response via the PI3K/AKT/mTOR signaling pathway after intracerebral hemorrhage

Preclinical and clinical studies have shown that microglia and macrophages participate in a multiphasic brain damage repair process following intracerebral hemorrhage.The E26 transformation-specific sequence-related transcription factor Spi1 regulates microglial/macrophage commitment and maturation.However,the effect of Spi1 on intracerebral hemorrhage remains unclear.In this study,we found that Spi1 may regulate recovery from the neuroinflammation and neurofunctional damage caused by intracerebral hemorrhage by modulating the microglial/macrophage transcriptome.We showed that high Spi1expression in microglia/macrophages after intracerebral hemorrhage is associated with the activation of many pathways that promote phagocytosis,glycolysis,and autophagy,as well as debris clearance and sustained remyelination.Notably,microglia with higher levels of Soil expression were chara cterized by activation of pathways associated with a variety of hemorrhage-related cellular processes,such as complement activation,angiogenesis,and coagulation.In conclusion,our results suggest that Spi1 plays a vital role in the microglial/macrophage inflammatory response following intracerebral hemorrhage.This new insight into the regulation of Spi1 and its target genes may advance our understanding of neuroinflammation in intracerebral hemorrhage and provide therapeutic targets for patients with intracerebral hemorrhage.

Alleviatory effect of isoquercetin on benign prostatic hyperplasia via IGF-1/PI3K/Akt/mTOR pathway

We evaluated the effect of isoquercetin(quercetin-O-3-glucoside-quercetin,IQ)as a functional component of Abeliophyllum disistichum Nakai ethanol extract(ADLE)on prostate cell proliferation and apoptosis and its effects on the IGF-1/PI3K/Akt/mTOR pathway in benign prostatic hyperplasia(BPH).Metabolites in ADLE were analyzed using UHPLC-qTOF-MS and HPLC.IQ was orally administered(1 or 10 mg/kg)to a testosterone propionate-induced BPH rat model,and its effects on the prostate weight were evaluated.The effect of IQ on androgen receptor(AR)signaling was analyzed in LNCaP cells.Whether IGF-1 and IQ affect the IGF-1/PI3K/Akt/mTOR pathway in BPH-1 cells was also examined.The metabolites in ADLE were identified and quantified,which confirmed that ADLE contained abundant IQ(20.88 mg/g).IQ significantly reduced the prostate size in a concentration-dependent manner in a BPH rat model,and significantly decreased the expression of AR signaling factors in the rat prostate tissue and LNCaP cells in a concentration-dependent manner.IQ also inhibited the PI3K/AKT/mTOR pathway activated by IGF-1 treatment in BPH-1 cells.In BPH-1 cells,IQ led to G0/G1 arrest and suppressed the expression of proliferation factors while inducing apoptosis.Thus,IQ shows potential for use as a pharmaceutical and nutraceutical for BPH.

LAMC2 regulates proliferation, migration, and invasion mediated by the Pl3K/AKT/mTOR pathway in oral

Background:Oral squamous cell carcinoma(OSCC)is a common malignant tumor.Recently,Laminin Gamma 2(LAMC2)has been shown to be abnormally expressed in OSCC;however,how LAMC2 signaling contributes to the occurrence and development of OSCC and the role of autophagy in OSCC has not been fully explored.This study aimed to analyze the role and mechanism of LAMC2 signaling in OSCC and the involvement of autophagy in OSCC.Methods:To explore the mechanism by which LAMC2 is highly expressed in OSCC,we used small interfering RNA(siRNA)to knock down LAMC2 to further observe the changes in the signaling pathway.Furthermore,we used cell proliferation assays,Transwell invasion assays,and wound-healing assays to observe the changes in OSCC proliferation,invasion,and metastasis.RFP-LC3 was used to detect the level of autophagy intensity.A cell line-derived xenograft(CDX)model was used to detect the effect of LAMC2 on tumor growth in vivo.Results:This study found that the level of autophagy was correlated with the biological behavior of OSCC.The downregulation of LAMC2 activated autophagy and inhibited OSCC proliferation,invasion,and metastasis via inhibiting the PI3K/AKT/mTOR pathway.Moreover,autophagy has a dual effect on OSCC,and the synergistic downregulation of LAMC2 and autophagy can inhibit OSCC metastasis,invasion,and proliferation via the PI3K/AKT/mTOR pathway.Conclusions:LAMC2 interacts with autophagy to regulate OSCC metastasis,invasion,and proliferation via the PI3K/AKT/mTOR pathway.LAMC2 down-regulation can synergistically modulate autophagy to inhibit OSCC migration,invasion,and proliferation.

Echinoside A from Pearsonothuria graeffei Exert the Cytotoxicity to MDA-MB-231 Cells via Mitochondrial Membrane and Modulation of PI3K/Akt/mTOR Pathway

A kind of triterpene glycosides echinoside A(EA)was extracted from sea cucumber Pearsonothuria graeffei,and its yield was about 0.78%.The purity of EA was 99.0%,and its molecular weight was 1206 Da.EA was a linear tetrasaccharide attached to a pentacyclic triterpene aglycon.It inhibited the growth of MDA-MB-231 cells in vitro.The antitumor effect was related to elevate ROS level,decrease mitochondrial membrane potential,enhance caspase-3 expression,induce cells apoptosis and arrest cell cycle at G2/M phase.EA also dose-dependently suppressed the expressions of phophorylation proteins p-PI3K,p-Akt,and p-mTOR as analyzed by western blotting.These results suggested that EA caused MDA-MB-231 cells apoptosis via intrinsic mitochondrial and PI3K/Akt/mTOR pathway.EA can be a potential anti-breast cancer agent to enhance the clinical efficacy.

PI3K/AKT/mTOR signaling pathway inhibitors in proliferation of retinal pigment epithelial cells

AIM: To determine whether the PI3K/AKT/mTOR pathway is activated in proliferative vitreoretinopathy (PVR) in homo-sapiens. METHODS: The retina of controls and patients with PVR were collected and their levels of PI3K, phospho-AKT, phospho-mTOR, phospho-p70S6k and phospho-4EBP-1 were determined by Western blot. The cultured human retinal pigment epithelial cell line D407 was treated with a specific mTOR inhibitor, rapamycin (RAPA) or a PI3K inhibitor, LY294002, of various concentrations and durations. Cell morphology was observed by phase contrast microscopy and the proliferation and apoptosis of treated cells were determined by MTT assay and flow cytometry. RESULTS: Levels of PI3K, phospho-AKT, phospho-mTOR, phospho-P70S6K and phospho-4EBP1 was increased in the retina in PVR (P <0.05). In D407 cells, both RAPA and LY294002 significantly inhibited cell proliferation and cell cycle progression, and promoted apoptosis (P <0.05); morphologically, the cells became smaller. Both RAPA and LY294002 reduced levels of phospho-AKT, phospho-mTOR, phospho-p70S6k and phospho-4EBP1 expression (P <0.05). RAPA, but not LY294002, had no significant effect on PI3K expression. CONCLUSION: PI3K/AKT/mTOR signaling pathway is highly activated in the retinal pigment epithelial cells of PVR. The inhibitors of PI3K/AKT/mTOR signaling pathway, RAPA and LY294002, could inhibited the PI3K/AKT/mTOR signaling pathway by reducing the levels of phosphorylation of mTOR pathway components.

Niuhuang(Bovis Calculus)-Shexiang(Moschus)combination induces apoptosis and inhibits proliferation in hepatocellular carcinoma via PI3K/AKT/mTOR pathway

Objective To investigate the effects of Niuhuang(Bovis Calculus,BC)and Shexiang(Moschus)(BC-Moschus)on human hepatocellular carcinoma(HCC)cells SMMC-7721 and a nude mouse model of subcutaneous xenografts,and to explore its anti-HCC mechanism.Methods The BC-Moschus combination was applied to two liver cancer models in vivo and in vitro.SMMC-7721 was divided into the BC-Moschus group and the control group,and different doses(rude drug dosage 0.625,1.25,2.5,and 5 mg/m L)of BC-Moschus extract were used for the intervention.The proliferation ability of HCC cells was detected using the Cell Counting Kit-8(CCK-8)assay,and the migration ability was detected by a wound healing assay.A subcutaneous xenograft model was prepared using nude mice with human HCC.Specific pathogen-free-grade BALB/c nude mice(5-week-old)were randomly divided into the following groups(n=6 per group):control(0.9%physiological saline 0.2 m L/d),BC-Moschus[BC 45.5 mg/(kg·d)+Moschus 13 mg/(kg·d)],and cisplatin(DDP,intraperitoneal injection5 mg/kg per week)groups.All groups were administered for 14 d.The volume and mass of the subcutaneous xenografts in nude mice were observed.The expression levels of phosphatidylinositol-3 kinase/protein kinase B/mammalian target of rapamycin(PI3K/AKT/mTOR)pathway,apoptosis-associated factor p70 S6 Kinase(S6K),Bax,Bcl-2,caspase-3,and caspase-9 in nude mice subcutaneous xenografts were measured by real-time quantitative PCR(RT-qPCR)and Western blot.Terminal Deoxynucleotidy Transferase-Mediated d UTP NickEnd Labeling(TUNEL)was used for quantitative analysis of apoptotic cells.Results The CCK-8 assay demonstrated that the BC-Moschus combination inhibited HCC cell proliferation in a superior manner to the use of BC and Moschus alone,and the inhibition effect was dose-and time-dependent(P<0.01).The wound healing assay showed that the BC-Moschus combination inhibited HCC cell migration(P<0.01).In the subcutaneous xenograft model of nude mice with human HCC,we found that the tumor volume and weight of the BC-Moschus group were lower than those of the control group(P<0.01).The levels of the PI3K/AKT/m TOR signaling pathway and S6K protein in the BC-Moschus and DDP groups were significantly decreased(P<0.01).The expression level of the anti-apoptotic gene Bcl-2 was downregulated(P<0.05),and the expression of the pro-apoptotic gene Baxand apoptosis-related factors caspase-3 and caspase-9 were significantly upregulated(P<0.01).The TUNEL assays further confirmed that the combination of the BC-Moschuas could promote HCC(P<0.01).Conclusion The BC-Moschus combination inhibited the proliferation and migration ability of HCC cells SMMC-7721 and effectively inhibited the growth of subcutaneous xenografts in nude mice.The mechanism may be closely related to the downregulation of the PI3K/AKT/mTOR pathway,regulation of apoptosis-related protein caspase-3,caspase-9,Bcl-2,and Bax expression,and promotion of apoptosis.

Acetylshikonin Inhibits Colorectal Cancer Growth via PI3K/Akt/mTOR Signaling Pathway

Background: Acetylshikonin, a major constituent isolated from Arnebia euchroma, is a potential candidate for anti-colorectal cancer drugs. However, the potential activity and underlying mechanism of Acetylshikonin against colorectal cancer remain unclear. Methods: In this study, Acetylshikonin was isolated from the active CHCl3 extract of Arnebia euchroma using activity-guided screening, and elucidated by the extensive spectroscopic analysis and comparison with literature data. Human colorectal cancer cells HT29, DLD-1, HCT116 or Caco-2 were exposed to different concentrations of Acetylshikonin (6.25 - 100 μg/mL) for 24 or 48 h. Cell viability, cell apoptosis and cell cycle distribution were detected. The activity of Acetylshikonin and potential mechanism of the phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway were evaluated in vitro and vivo. Results: We found that Acetylshikonin exhibited remarkable anti-proliferative activity in a dose-dependent manner against HT29 cells with the IC50 values of 60.82 μg/ml and 30.78 μg/ml at 24, 48 h, respectively. Moreover, Acetylshikonin induced cell cycle arrest at G0/G1 phase and early apoptosis through inhibition of PI3K/Akt/mTOR pathway. Furthermore, the assays of cell inhibition, early apoptosis and G0/G1 phase distribution showed that suppression of the PI3K/Akt pathway using LY294002 enhanced the anti-cancer effect of Acetylshikonin. Similarly, Acetylshikonin also decreased the growth of tumour in colorectal cancer xenografts in mice through PI3K/Akt/mTOR pathway. Conclusions: To sum up, these new findings provided a framework for further exploration of Acetylshikonin which possessed the potential antitumor activity by inhibiting PI3K/Akt/mTOR pathway.

Effects of Liancao-Xieli capsule on intestinal mucosal inflammatory factors and TLR4/PI3K/Akt/mTOR signaling pathway in mice with ulcerative colitis

Objective:To observe the effect of Liancao-Xieli capsule on intestinal mucosal inflammatory factors and TLR4/PI3K/Akt/mTOR signaling pathway in mice with ulcerative colitis(UC);Methods:40 male C57BL/6 mice were randomly divided into the control group,model group,Liancao-Xieli group and mesalazine group,with 10 mice in each group.In addition to the control group,the remaining three groups of mice were induced by 3%dextran sulfate sodium(DSS)to induce acute UC model.During the modeling period,mice in each group were given corresponding drugs and normal saline by gavage.At the end of the experiment,HE staining was used to observe the pathological changes of colonic tissue in each group,and ELISA was used to detect the inflammatory factors(TNF-α,IL-6,IL-1β,IL-8,IL-17,and INF-γ)in serum and colonic tissue.The expression levels of TLR4/PI3K/Akt/mTOR signaling pathway related proteins were also detected by Western blot;Results:Compared with the model group,Liancao-Xieli capsule could significantly increase the colon length and decrease the score of colon histopathology in UC mice(P<0.01).In addition,the levels of TNF-α,IL-6,IL1β,IL-8,IL-17,and INF-γwere significantly reduced in serum and colon tissue,and the expressions of TLR4,PI3K,p-Akt and p-mTOR were significantly down-regulated in LiancaoXieyi group when compared with the model group(P<0.01).While the expressions of Akt and mTOR were not significantly affected in Liancao-Xieyi group(P>0.05);Conclusion:LiancaoXieli capsule can reduce the secretion of inflammatory factors,improve the intestinal mucosal damage and inflammatory response in UC by inhibiting the activation of TLR4/PI3K/Akt/mTOR signaling pathway。

Study on biological behavior and mechanism of icariin on mouse melanoma B16 cells by regulating PI3K/AKT/mTOR pathway

Objective:To study the effect and mechanism of icariin on the migration,proliferation and apoptosis of mouse melanoma B16 cells.Methods:Mouse melanoma B16 cells were treated with icariin at different concentrations(0,10,20,50μmol/L)for 24 hours.Cell proliferation,morphology,apoptosis and migration ability were detected,and the expression of PI3K/AKT/mTOR pathway related proteins was detected by Western blot assay.Results:After treatment with icariin,the inhibition rate and apoptosis rate of mouse melanoma B16 cells increased significantly with the increase of administration concentration(P<0.05).Hoechst 33258 staining showed that the cells in the blank control group(0μmol/L)were uniformly stained and the color was lighter,while the cells in the experimental group containing icariin were thicker in color.The higher the concentration of the icariin,the more obvious the degree of chromatin aggregation.The scratch healing rate of B16 cells and the cell count on the bottom of Transwell membrane decreased significantly with the increase of icariin concentration(P<0.05).The results of protein detection showed that with the increase of administration concentration,the expression of MMP-9,MMP-2 and mTOR decreased significantly,while the ratio of PI3K/pPI3K and AKT/pAKT increased significantly,and there was significant difference between the groups(P<0.05).Conclusions:Icariin can effectively inhibit the expression of PI3K/AKT/mTOR pathway related proteins in mouse melanoma B16 cells,thus inducing apoptosis of tumor cells,inhibiting cell migration and finally exerting antitumor effect.

Magnolol and 5-fluorouracil synergy inhibition of metastasis of cervical cancer cells by targeting PI3K/AKT/mTOR and EMT pathways

Objective: This study is designed to investigate the mode of action of the synergistic effect of 5-fluorouracil(5-FU) and magnolol against cervical cancer.Methods: Network pharmacological approach was applied to predict the molecular mechanism of 5-FU combined with magnolol against cervical cancer. CCK-8 assay, colony formation assay, immunofluorescence staining, adhesion assay, wound healing mobility assay, cell migration and invasion assay and Western blot analysis were conducted to validate the results of in silico study.Results: Phosphatidylinositol 3 kinase(PI3K)/protein kinase B(AKT)/mammalian target of rapamycin(mTOR) signaling pathway was identified as the key pathway in silico study. The experimental results showed that 5-FU combined with magnolol strongly inhibited cervical cancer cell proliferation, induced the morphological change of HeLa cells by down-regulating the expression of a-actinin, tensin-2 and vinculin. Moreover, magnolol enhanced inhibitory effect of 5-FU on the cell adhesion, migration and invasion. The phosphorylation of AKT and PI3K and the expression of mTOR were strongly inhibited by the combination of 5-FU and magnolol. Moreover, the expression of E-cadherin and β-catenin was upregulated and the expression of Snail, Slug and vimentin was down-regulated by the 5-FU together with magnolol.Conclusion: Taken together, this study suggests that 5-FU combined with magnolol exerts a synergistic anti-cervical cancer effect by regulating the PI3K/AKT/mTOR and epithelial-mesenchymal transition(EMT) signaling pathways.

The molecular genetics of PI3K/PTEN/AKT/mTOR pathway in the malformations of cortical development

Malformations of cortical development(MCD)are a group of developmental disorders characterized by abnormal cortical structures caused by genetic or harmful environmental factors.Many kinds of MCD are caused by genetic variation.MCD is the common cause of intellectual disability and intractable epilepsy.With rapid advances in imaging and sequencing technologies,the diagnostic rate of MCD has been increasing,and many potential genes causing MCD have been successively identified.However,the high genetic heterogeneity of MCD makes it challenging to understand the molecular pathogenesis of MCD and to identify effective targeted drugs.Thus,in this review,we outline important events of cortical development.Then we illustrate the progress of molecular genetic studies about MCD focusing on the PI3K/PTEN/AKT/mTOR pathway.Finally,we briefly discuss the diagnostic methods,disease models,and therapeutic strategies for MCD.The information will facilitate further research on MCD.Understanding the role of the PI3K/PTEN/AKT/mTOR pathway in MCD could lead to a novel strategy for treating MCD-related diseases.

PI3K/Akt/mTOR Signaling as Targets for Developing Anticancer Agents from Marine Organisms

The PI3K/Akt/mTOR signaling pathway is one of the most frequently dysregulated pathways in cancer.Targeting the PI3K-mediated pathway has been an important strategy for developing novel anticancer agents.In the past decades,more than 40 inhibitors of the PI3K/Akt/mTOR pathway have been developed at different clinical stages.Temsirolimus,everolimus,idelalisib,and copanlisib have been approved for clinical use by the Food and Drug Administration of the United States(FDA).However,the toxic-ity and drug resistance limit their efficiency in the treatment.Novel compounds with greater potency and selectivity,as well as im-proved therapeutic indices with reduced toxicity,are clearly required.Over the past three decades,a lot of bioactive ingredients with anticancer effects by affecting the PI3K-mediated pathways have been found from marine organisms.In the present mini-review,anticancer compounds from marine source that target the PI3K/Akt/mTOR signaling were reviewed.The molecular entities and their modes of action were presented.The marine compounds targeting special factors of the PI3K/Akt/mTOR were highlighted.

Regulatory Effects of Zuogui Pill on Apoptosis of Follicles in Rats Injured by 60Co-γRays Based on PI3K/Akt/m TOR Signaling Pathway

[Objectives]To explore the protective effects of Zuogui Pill on ^(60)Co-γ-ray-induced premature aging of rats based on phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/Akt/mTOR)signaling pathway.[Methods]Sixty sexually mature female SD rats were irradiated with ^(60)Co-γ-ray(6.0 Gy,LD 40)for 24 h at one time.These rats were randomly divided into model group,Progynova group[0.18(g·kg)/d],Progynova[0.09(g·kg)/d]+Zuogui Pill high dose[23.625(g·kg)/d)]group,Zuogui Pill high dose[23.625(g·kg)/d)]group,Zuogui Pill medium dose[9.45(g·kg)/d)]group and Zuogui Pill low dose[4.725(g·kg)/d]group.The administration(once a day)lasted 21 d.The rat serum[follicle-stimulating hormone(FSH),luteinizing hormone(LH)and estradiol(E_(2))]were detected by Enzyme-linked immunosorbent assay(ELISA).The morphological changes of ovary were observed by hematoxylin-eosin(HE)staining.The apoptosis rate of granulosa cells was detected by terminal deoxynucleotidyl transferase(TdT)-mediated dUTP nick-end labeling(TUNEL).The protein expression of phosphorylated(p)-PI3K,p-Akt,p-mTOR,B-cell lymphoma-2(Bcl-2),and Bcl-2-associated X protein(Bax)in ovarian tissues were detected by Western blot.[Results]Compared with the normal group,the model group showed significant increase in the serum FSH(P<0.01),significant decrease in serum E_(2)(P<0.05),and decrease in the number of early follicles and luteum in the ovary(P<0.01).Besides,the apoptosis rate of granulosa cells increased significantly(P<0.01);the expression of p-PI3K,p-Akt,p-mTOR and Bcl-2 in ovarian tissue decreased significantly,while the expression of Bax increased significantly(P<0.01).Compared with the model group,the number of early follicles in the ovary increased and the apoptosis rate of granulosa cells decreased after intervention in each administration group.In addition,the protein expressions of p-PI3K,p-Akt,p-mTOR and Bcl-2 increased,while the expression of Bax decreased,especially in Progynova+Zuogui Pill high dose group,the differences were statistically significant(P<0.05,P<0.01).[Conclusions]Zuogui Pill may protect the radiation-injured ovary through activating the expression of PI3K/Akt/mTOR protein in ovarian tissue,increasing the amount of Bcl-2 protein and inhibiting the expression of Bax protein.

Suppression of Amino Acid Transporter LAT3 Expression on Proliferation of K562 Cells

The activity of the mTOR pathway is frequently increased in acute myeloid leukemia, and is tightly related with cellular proliferation. Leucine is tightly linked to the mTOR pathway and can acti- vate it, thereby stimulating cellular proliferation. LAT3 is a major transporter for leucine, and suppres- sion of its expression can reduce cell proliferation. Here, we show that suppression of LAT3 expression can reduce proliferation of the acute leukemia cell line, K562. We investigated the mRNA and protein expression of LAT3 in several leukemia cell lines and normal peripheral blood mononuclear cells （PBMNCs） using RT-PCR and Western blotting. We also evaluated cell viability using a methyl thia- zolyl tetrazolium （MTT） assay after blocking LAT3 expression with either shRNA targeted to LAT3 or a small molecular inhibitor BCH （2-aminobicyclo-（2,2,1）-heptane-2-carboxylic acid）. LAT3 mRNA and protein expression was detected in leukemia cell lines, but not in normal PBMNCs. Using K562 cells, it was found that cellular proliferation and mTOR pathway activity were significantly reduced when LAT3 was blocked with either shRNA or BCH. Our results suggest that leukemia cell proliferation can be sig- nificantly suppressed by blocking LAT3. This finding may lead to a new strategy to develop clinical therapy for the treatment of acute myeloid leukemia.

Biomimetic hydroxyapatite coating on the 3D-printed bioactive porous composite ceramic scaffolds promoted osteogenic differentiation via PI3K/AKT/mTOR signaling pathways and facilitated bone regeneration in vivo

The architecture and surface modifications have been regarded as effective methods to enhance the bi-ological response of biomaterials in bone tissue engineering.The porous architecture of the implanta-tion was essential conditions for bone regeneration.Meanwhile,the design of biomimetic hydroxyap-atite(HAp)coating on porous scaffolds was demonstrated to strengthen the bioactivity and stimulate osteogenesis.However,bioactive bio-ceramics such asβ-tricalcium phosphate(β-TCP)and calcium sili-cate(CS)with superior apatite-forming ability were reported to present better osteogenic activity than that of HAp.Hence in this study,3D-printed interconnected porous bioactive ceramicsβ-TCP/CS scaf-fold was fabricated and the biomimetic HAp apatite coating were constructed in situ via hydrothermal reaction,and the effects of HAp apatite layer on the fate of mouse bone mesenchymal stem cells(mBM-SCs)and the potential mechanisms were explored.The results indicated that HAp apatite coating en-hanced cell proliferation,alkaline phosphatase(ALP)activity,and osteogenic gene expression.Further-more,PI3K/AKT/mTOR signaling pathway is proved to have an important impact on cellular functions.The present results demonstrated that the key molecules of phosphatidylinositol 3-kinase(PI3K),protein kinase B(AKT)and mammalian target of rapamycin(mTOR)were activated after the biomimetic hydrox-yapatite coating were constructed on the 3D-printed ceramic scaffolds.Besides,the activated influence on the protein expression of Runx2 and BMP2 could be suppressed after the treatment of inhibitor HY-10358.In vivo studies showed that the constructed HAp coating promoted bone formation and strengthen the bone quality.These results suggest that biomimetic HAp coating constructed on the 3D-printed bioac-tive composite scaffolds could strengthen the bioactivity and the obtained biomimetic multi-structured scaffolds might be a potential alternative bone graft for bone regeneration.

PI3K/AKT/mTOR pathway,hypoxia,and glucose metabolism:Potential targets to overcome radioresistance in small cell lung cancer

Small cell lung cancer(SCLC)is a highly aggressive tumor type for which limited therapeutic progress has been made.Platinum-based chemotherapy with or without thoracic radiotherapy remains the backbone of treatment,but most patients with SCLC acquire therapeutic resistance.Given the need for more effective therapies,better elucidation of the molecular pathogenesis of SCLC is imperative.The phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)/mammalian target of rapamycin(mTOR)pathway is frequently activated in SCLC and strongly associated with resistance to ionizing radiation in many solid tumors.This pathway is an important regulator of cancer cell glucose metabolism,and its activation probably effects radioresistance by influencing bioenergetic processes in SCLC.Glucose metabolism has three main branches-aerobic glycolysis,oxidative phosphorylation,and the pentose phosphate pathway-involved in radioresistance.The interaction between the PI3K/AKT/mTOR pathway and glucose metabolism is largely mediated by hypoxia-inducible factor 1(HIF-1)signaling.The PI3K/AKT/mTOR pathway also influences glucose metabolism through other mechanisms to participate in radioresistance,including inhibiting the ubiquitination of rate-limiting enzymes of the pentose phosphate pathway.This review summarizes our understanding of links among the PI3K/AKT/mTOR pathway,hypoxia,and glucose metabolism in SCLC radioresistance and highlights promising research directions to promote cancer cell death and improve the clinical outcome of patients with this devastating disease.

基于磷脂酰肌醇3激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路小干扰RNA沉默微小RNA-373对喉癌细胞的影响

目的 探讨磷脂酰肌醇3激酶(Phosphatidylinositol 3 kinase,PI3K)/蛋白激酶B(Protein kinase B,Akt)/雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)信号通路小干扰RNA(Small interfering RNA,siRNA)沉默微小RNA-373(Microrna-373,miR-373)对喉癌细胞生物学行为的影响。方法 喉癌TU212细胞株经常规培养后分为空白组、空白转染组、过表达组和沉默组,四组细胞分别培养。检测各组细胞增殖、凋亡、迁移、侵袭能力及PI3K/AKT/mTOR通路蛋白表达。结果 与过表达组相比,沉默组miR-373、P13K、AKT、mTOR表达量较低(P<0.05);沉默组24、48、72 h细胞增殖率较低,72 h细胞凋亡率较高(P<0.05);沉默组细胞迁移率较少、侵袭数较少(P<0.05)。结论 沉默miR-373可能通过作用于PI3K/AKT/mTOR信号通路,下调P13K、AKT、mTOR表达,抑制喉癌细胞增殖、迁移、侵袭,促进凋亡。

CD26 upregulates proliferation and invasion in keloid fibroblasts through an IGF-1-induced PI3K/AKT/mTOR pathway

Background:Keloid is a fibrotic dermal disease characterized by an abnormal increase in fibroblast proliferation and invasion.These pathological behaviours may be related to the heterogeneity of keloid fibroblasts(KFs);however,because of a lack of effective biomarkers for KFs it is difficult to study the underlying mechanism.Our previous studies revealed that the expansion of CD26+KFs was responsible for increased keloid proliferation and invasion capabilities;the intrinsic relationship and mechanism between CD26 and keloid is therefore worthy of further investigation.The aim of this studywas to explore molecular mechanisms in the process of CD26 upregulated KFs proliferation and invasion abilities,and provide more evidence for CD26 as an effective biomarker of keloid and a new clinical therapeutic target.Methods:Flow cytometry was performed to isolate CD26+/CD26−fibroblasts from KFs and normal fibroblasts.To generate stably silenced KFs for CD26 and insulin-like growth factor-1 receptor(IGF-1R),lentiviral particles encoding shRNA targeting CD26 and IGF-1R were used for transfection.Cell proliferations were analysed by cell counting kit-8 assay and 5-ethynyl-2-deoxyuridine(EdU)incorporation assay.Scratching assay and transwell assay were used to assess cell migration and invasion abilities.To further quantify the regulatory role of CD26 expression in the relevant signalling pathway,RT-qPCR,western blot,ELISA,PI3K activity assay and immunofluorescence were used.Results:Aberrant expression of CD26 in KFs was proven to be associated with increased proliferation and invasion of KFs.Furthermore,the role of the IGF-1/IGF-1 receptor axis was also studied in CD26 and was found to upregulate KF proliferation and invasion.The PI3K/protein kinase B(AKT)/mammalian target of rapamycin(mTOR)pathway was shown to affect CD26-regulated KF proliferation and invasion by increasing phosphorylation levels of S6 kinase and 4E-binding protein.Conclusions:CD26 can be the effective biomarker for KFs,and its expression is closely related to proliferation and invasion in keloids through the IGF-1-induced PI3K/AKT/mTOR pathway.This work provides a novel perspective on the pathological mechanisms affecting KFs and therapeutic strategies against keloids.

Schwann cells differentiated from skin-derived precursors provide neuroprotection via autophagy inhibition in a cellular model of Parkinson’s disease

Autophagy has been shown to play an important role in Parkinson’s disease.We hypothesized that skin-derived precursor cells exhibit neuroprotective effects in Parkinson’s disease through affecting autophagy.In this study,6-hydroxydopamine-damaged SH-SY5Y cells were pretreated with a culture medium containing skin-derived precursors differentiated into Schwann cells(SKP-SCs).The results showed that the SKP-SC culture medium remarkably enhanced the activity of SH-SY5Y cells damaged by 6-hydroxydopamine,reduced excessive autophagy,increased tyrosine hydroxylase expression,reducedα-synuclein expression,reduced the autophagosome number,and activated the PI3K/AKT/mTOR pathway.Autophagy activator rapamycin inhibited the effects of SKP-SCs,and autophagy inhibitor 3-methyladenine had the opposite effect.These findings confirm that SKP-SCs modulate the PI3K/AKT/mTOR pathway to inhibit autophagy,thereby exhibiting a neuroprotective effect in a cellular model of Parkinson’s disease.This study was approved by the Animal Ethics Committee of Laboratory Animal Center of Nantong University(approval No.S20181009-205)on October 9,2018.

The role of the PI3K/AKT/mTOR pathway in brain tumor metastasis

The PI3K/AKT/mTOR(PAM)pathway is involved in a variety of cellular functions and often contributes to oncogenesis and cancer progression.It has been recognized that this pathway is frequently activated in the most common central nervous system cancers of adults and children,malignant gliomas and medulloblastomas(MB).In these tumors,the PAM network controls key functions necessary for cell invasion and metastasis,such as cell motility.This review summarizes the current knowledge about the role of PAM signaling in cell invasion and metastasis in gliomas and MB.Current approaches to inhibit cell invasion and metastasis by targeting the PAM pathway will also be discussed.