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.

Protective effects of panax notoginseng saponin on dextran sulfate sodium-induced colitis in rats through phosphoinositide-3-kinase protein kinase B signaling pathway inhibition

BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many complications.AIM To explore the protective effects of panax notoginseng saponin(PNS) against dextran sulfate sodium(DSS)-induced intestinal inflammatory injury through phosphoinositide-3-kinase protein kinase B(PI3K/AKT) signaling pathway inhibition in rats.METHODS Colitis rat models were generated via DSS induction, and rats were divided into control(no modeling), DSS, DSS + PNS 50 mg/k, and DSS + PNS 100 mg/kg groups. Then, the intestinal injury, oxidative stress parameters, inflammatory indices, tight junction proteins, apoptosis, macrophage polarization, and TLR4/AKT signaling pathway in colon tissues from rats in each of the groups were detected. The PI3 K/AKT signaling pathway in the colon tissue of rats was blocked using the PI3K/AKT signaling pathway inhibitor, LY294002.RESULTS Compared with rats in the control group, rats in the DSS group showed significantly shortened colon lengths, and significantly increased disease activity indices, oxidative stress reactions and inflammatory indices, as well as significantly decreased expression of tight junction-associated proteins. In addition, the DSS group showed significantly increased apoptotic cell numbers,and showed significantly increased M1 macrophages in spleen and colon tissues.They also showed significantly decreased M2 macrophages in colon tissues, as well as activation of the PI3K/AKT signaling pathway(all P < 0.05). Compared with rats in the DSS group, rats in the DSS + PNS group showed significantly lengthened colon lengths, decreased disease activity indices, and significantly alleviated oxidative stress reactions and inflammatory responses. In addition, this group showed significantly increased expression of tight junction-associated proteins, significantly decreased apoptotic cell numbers, and significantly decreased M1 macrophages in spleen and colon tissues. This group further showed significantly increased M2 macrophages in colon tissues, and significantly suppressed activation of the PI3K/AKT signaling pathway, as well as a dose dependency(all P < 0.05). When the PI3K/AKT signaling pathway was inhibited, the apoptosis rate of colon tissue cells in the DSS + LY294002 group was significantly lower than that of the DSS group(P < 0.05).CONCLUSION PNS can protect rats against DSS-induced intestinal inflammatory injury by inhibiting the PI3K/AKT signaling pathway, and therefore may be potentially used in the future as a drug for colitis.

Bornyl acetate extracted from Sharen(Fructus Amomi)inhibits proliferation,invasion and induces apoptosis by suppressing phosphatidylinositol-3-kinase/protein kinase B signaling in colorectal cancer

OBJECTIVE:To investigate the antitumor effects of bornyl acetate(BA)isolated from Sharen(Fructus Amomi)in colorectal cancer(CRC)and the underlying mechanisms.METHODS:SW480 and HT29 cells were treated with increasing doses of BA in order to determine its antitumor effects in vitro.Cell viability,colony formation,cell cycle,and apoptosis as well as migration and invasion were assessed using various assays.In addition,the in vivo antitumor effects of BA were assessed using a xenograft mouse model.We then assessed the mechanism of action of BA by conducting pathway activator-mediated rescue experiments and assessed the protein levels by Western blot analysis.RESULTS:BA showed anti-CRC tumor activities in vitro by suppressing cell proliferation and colony formation,inducing apoptosis,blocking cell cycle,and inhibiting migration and invasion.These effects were mediated via suppression of the phosphatidylinositol-3-kinase/protein kinase B(PI3K/AKT)pathway.In the tumor xenograft experiment,BA was found to repress tumor growth in vivo with low toxicity.CONCLUSIONS:The results demonstrated that BA exerts antitumor effects by suppressing the PI3K/AKT pathway,with low toxicity.Thus,BA might be a potential novel therapeutic agent for CRC.

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.

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.

Bone marrow-derived mesenchymal stem cells modulate autophagy in RAW264.7 macrophages via the phosphoinositide 3-kinase/protein kinase B/heme oxygenase-1 signaling pathway under oxygen-glucose deprivation/restoration conditions

Background: Autophagy of alveolar macrophages is a crucial process in ischemia/reperfusion injury-induced acute lung injury (ALI). Bone marrow-derived mesenchymal stem cells (BM-MSCs) are multipotent cells with the potential for repairing injured sites and regulating autophagy. This study was to investigate the influence of BM-MSCs on autophagy of macrophages in the oxygen-glucose deprivation/restoration (OGD/R) microenvironment and to explore the potential mechanism.Methods: We established a co-culture system of macrophages (RAW264.7) with BM-MSCs under OGD/R conditionsin vitro. RAW264.7 cells were transfected with recombinant adenovirus (Ad-mCherry-GFP-LC3B) and autophagic status of RAW264.7 cells was observed under a fluorescence microscope. Autophagy-related proteins light chain 3 (LC3)-I, LC3-II, and p62 in RAW264.7 cells were detected by Western blotting. We used microarray expression analysis to identify the differently expressed genes between OGD/R treated macrophages and macrophages co-culture with BM-MSCs. We investigated the gene heme oxygenase-1 (HO-1), which is downstream of the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling pathway.Results: The ratio of LC3-II/LC3-I of OGD/R treated RAW264.7 cells was increased (1.27 ± 0.20vs. 0.44 ± 0.08,t = 6.67,P < 0.05), while the expression of p62 was decreased (0.77 ± 0.04vs. 0.95 ± 0.10,t = 2.90,P < 0.05), and PI3K (0.40 ± 0.06vs. 0.63 ± 0.10,t = 3.42,P < 0.05) and p-Akt/Akt ratio was also decreased (0.39 ± 0.02vs. 0.58 ± 0.03,t = 9.13,P < 0.05). BM-MSCs reduced the LC3-II/LC3-I ratio of OGD/R treated RAW264.7 cells (0.68 ± 0.14vs. 1.27 ± 0.20,t = 4.12,P < 0.05), up-regulated p62 expression (1.10 ± 0.20vs. 0.77 ± 0.04,t = 2.80,P < 0.05), and up-regulated PI3K (0.54 ± 0.05vs. 0.40 ± 0.06,t = 3.11,P < 0.05) and p-Akt/Akt ratios (0.52 ± 0.05vs. 0.39 ± 0.02,t = 9.13,P < 0.05). A whole-genome microarray assay screened the differentially expressed geneHO-1, which is downstream of the PI3K/Akt signaling pathway, and the alteration ofHO-1 mRNA and protein expression was consistent with the data on PI3K/Akt pathway.Conclusions: Our results suggest the existence of the PI3K/Akt/HO-1 signaling pathway in RAW264.7 cells under OGD/R circumstancesin vitro, revealing the mechanism underlying BM-MSC-mediated regulation of autophagy and enriching the understanding of potential therapeutic targets for the treatment of ALI.

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.

Impaired PI3K/Akt signal pathway and hepatocellular injury in high-fat fed rats

AIM:To determine whether mitochondrial dysfunction resulting from high-fat diet is related to impairment of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt,also known as PKB) pathway. METHODS:Rat models of nonalcoholic fatty liver were established by high-fat diet feeding. The expression of total and phosphorylated P13K and Akt proteins in hepatocytes was determined by Western blotting. Degree of fat accumulation in liver was measured by hepatic triglyceride. Mitochondrial number and size were determined using quantitative morphometric analysis under transmission electron microscope. The permeability of the outer mitochondrial membrane was assessed by determining the potential gradient across this membrane.RESULTS:After Wistar rats were fed with high-fat diet for 16 wk,their hepatocytes displayed an accumulation of fat (103.1 ± 12.6 vs 421.5 ± 19.7,P < 0.01),deformed mitochondria (9.0% ± 4.3% vs 83.0% ± 10.9%,P < 0.05),and a reduction in the mitochondrial membrane potential (389.385% ± 18.612% vs 249.121% ± 13.526%,P < 0.05). In addition,the expression of the phosphorylated P13K and Akt proteins in hepatocytes was reduced,as was the expression of the anti-apoptotic protein Bcl-2,while expression of the pro-apoptotic protein caspase-3 was increased. When animals were treated with pharmacological inhibitors of P13K or Akt,instead of high-fat diet,a similar pattern of hepatocellular fat accumulation,mitochondrial impairment,and change in the levels of PI3K,Akt,Bcl-2 was observed. CONCLUSION:High-fat diet appears to inhibit the PI3K/Akt signaling pathway,which may lead to hepa-tocellular injury through activation of the mitochondrial membrane pathway of apoptosis.

LAIR-1通过阻断JAK2 V617F突变的人HEL细胞JAK/STAT和PI3K/AKT/mTOR信号通路抑制其增殖并促进其凋亡

目的研究人白细胞相关免疫球蛋白样受体1(LAIR-1)对Janus激酶2(JAK2)V617F突变的人急性髓系白血病HEL细胞JAK/信号转导子与转录激活子(STAT)和磷脂酰肌醇3激酶/蛋白激酶B/哺乳动物雷帕霉素靶蛋白(PI3K/AKT/mTOR)信号通路的调节作用,以及对细胞增殖和凋亡的影响。方法采用反转录PCR和基因测序鉴定JAK2 V617F突变;应用免疫共沉淀和Western blot法鉴定LAIR-1募集的蛋白酪氨酸磷酸酶(PTP)种类;采用CCK-8法检测HEL细胞的增殖;采用异硫氰酸荧光素标记的膜联素Ⅴ/碘化丙啶(annexinⅤ-FITC/PI)双标记结合流式细胞术检测HEL细胞的凋亡率;采用Western blot法检测JAK/STAT和PI3K/AKT/mTOR通路蛋白酪氨酸磷酸化水平及细胞周期蛋白D1(cyclin D1)、Bcl2相关X蛋白(BAX)和B细胞淋巴瘤因子2(Bcl2)的蛋白表达。结果在JAK2 V617F突变的HEL细胞中,LAIR-1与其配体胶原蛋白结合后可募集含Src同源域2磷酸酶2(SHP-2);LAIR-1可以下调HEL细胞JAK2、STAT1、STAT3、STAT5、AKT和mTOR的蛋白酪氨酸磷酸化水平,并能够显著抑制cyclin D1和Bcl2的表达,而对BAX的表达水平未见显著影响;LAIR-1能够明显抑制HEL细胞的增殖,促进HEL细胞凋亡。结论在JAK2 V617F突变的人白血病HEL细胞中,LAIR-1可通过募集SHP-2抑制JAK/STAT和PI3K/AKT/mTOR信号通路的活化,进而抑制HEL细胞的增殖,促进细胞凋亡。

Scorpiones,Scolopendra and Gekko Inhibit Lung Cancer Growth and Metastasis by Ameliorating Hypoxic Tumor Microenvironment via PI3K/AKT/mTOR/HIF-1αSignaling Pathway

Objective:To investigate whether Buthus martensii karsch(Scorpiones),Scolopendra subspinipes mutilans L.Koch(Scolopendra)and Gekko gecko Linnaeus(Gekko)could ameliorate the hypoxic tumor microenvironment and inhibit lung cancer growth and metastasis by regulating phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin/hypoxia-inducible factor-1α(PI3K/AKT/mTOR/HIF-1α)signaling pathway.Methods:Male C57BL/6J mice were inoculated with luciferase labeled LL/2-luc-M38 cell suspension to develop lung cancer models,with rapamycin and cyclophosphamide as positive controls.Carboxy methyl cellulose solutions of Scorpiones,Scolopendra and Gekko were administered intragastrically as 0.33,0.33,and 0.83 g/kg,respectively once daily for 21 days.Fluorescent expression were detected every 7 days after inoculation,and tumor growth curves were plotted.Immunohistochemistry was performed to determine CD31 and HIF-1αexpressions in tumor tissue and microvessel density(MVD)was analyzed.Western blot was performed to detect the expression of PI3K/AKT/mTOR/HIF-1αsignaling pathway-related proteins.Enzyme-linked immunosorbent assay was performed to detect serum basic fibroblast growth factor(bFGF),transforming growth factor-β1(TGF-β1)and vascular endothelial growth factor(VEGF)in mice.Results:Scorpiones,Scolopendra and Gekko prolonged the survival time and inhibited lung cancer metastasis and expression of HIF-1α(all P<0.01).Moreover,Scorpiones,Scolopendra and Gekko inhibited the phosphorylation of AKT and ribosomal protein S6 kinase(p70S6K)(P<0.05 or P<0.01).In addition,they also decreased the expression of CD31,MVD,bFGF,TGF-β1 and VEGF compared with the model group(P<0.05 or P<0.01).Conclusion:Scorpiones,Scolopendra and Gekko all showed beneficial effects on lung cancer by ameliorating the hypoxic tumor microenvironment via PI3K/AKT/mTOR/HIF-1αsignaling pathway.

弥漫大B细胞淋巴瘤中铁死亡相关基因的表达及其与免疫细胞和信号通路的关系

目的通过癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库分析弥漫大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)中铁死亡相关基因的表达及其与程序性死亡受体配体-1(programmed death ligand-1,PD-L1)和免疫细胞的关系,为DLBCL的治疗提供新的靶标。方法通过TCGA数据库查找获得22个铁死亡相关基因。从TCGA数据库获取48例DLBCL(DLBCL组)及54例反应性淋巴结增生患者(对照组)淋巴结标本的铁死亡相关基因以及PD-L1的表达数据。使用Wilcoxon秩和检验进行组间差异性表达分析。基因表达相关性分析采用Spearman相关性分析。采用R软件包pheatmap分析DLBCL中铁死亡相关基因表达与免疫细胞的相关性。采用R软件GSVA包分析铁死亡相关基因表达与磷脂酰肌醇-3-激酶-蛋白激酶B-哺乳动物雷帕霉素靶蛋白(phosphatidylinositol 3 kinase-protein kinase B-mammalian target of rapamycin,PI3K-Akt-mTOR)信号通路的相关性。结果DLBCL中周期素依赖性激酶抑制因子1A(cyclin dependent kinase inhibitor 1A,CDKN1A)、70 kDa热休克蛋白5(heat shock 70 kDa protein 5,HSPA5)、内质膜蛋白复合体亚基2(endoplasmic membrane protein complex subunit 2,EMC2)、溶质载体家族7成员11(solute carrier family 7,member 11,SLC7A11)、金属硫蛋白1G(metallothionein 1G,MT1G)、热休克蛋白B1(heat shock protein B1,HSPB1)、谷胱甘肽过氧化酶4(glutathione peroxidase4,GPX4)、范可尼贫血互补群D2(Fanconi anemia complementary group D2,FANCD2)、柠檬酸合成酶(citrate synthase,CS)、CDGSH铁硫结构域1(CDGSH iron sulfur domain 1,CISD1)、法尼基二磷酸法尼基转移酶1(farnesyl diphosphate farnesyltransferase 1,FDFT1)、SLC1A5、转铁蛋白受体(transferrin receptor,TFRC)、核糖体蛋白L8(ribosomal protein L8,RPL8)、核受体共激活因子4(nuclear receptor coativator 4,NCOA4)、二肽基肽酶Ⅳ(dipeptidyl peptidaseⅣ,DPP4)和花生四烯酸15脂氧合酶(arachidonate-15-lipoxygenase,ALOX15)基因表达均上调(均P<0.05)。免疫细胞相关分析显示,铁死亡相关基因可激活体内巨噬细胞M1(P<0.05)。DLBCL中长链脂酰辅酶A合成酶4(acyl-CoA synthetase long chain family member 4,ACSL4)、CDKN1A、DPP4、EMC2、谷氨酰胺酶2(glutaminase 2,GLS2)、HSPA5、溶血卵磷脂酰基转移酶3(lysophosphatidylcholine acyltransferase 3,LPCAT3)、MT1G、NCOA4、红细胞衍生核因子2样蛋白2(nuclear factor erythroid 2-like-2,NFE2L2)、精脒/精胺N1-乙酰基转移酶1(spermidine/spermine N1-acetyltransferase 1,SAT1)、SLC7A11和TFRC这些铁死亡相关基因的表达均与PD-L1表达呈正相关(均r>0.4,均P<0.05)。铁死亡相关基因LPCAT3、NCOA4和TFRC的表达均与PI3K-AktmTOR通路呈正相关(均r>0.4,均P<0.05)。结论多数铁死亡相关基因在DLBCL组织中高表达,且与PD-L1、免疫浸润及PI3K-Akt-mTOR通路有关。

Hydroxysafflor Yellow A Promotes HaCaT Cell Proliferation and Migration by Regulating HBEGF/EGFR and PI3K/AKT Pathways and Circ_0084443

Objective:To investigate the effect and possible mechanism of hydroxysafflor yellow A(HSYA) on human immortalized keratinocyte cell proliferation and migration.Methods:HaCaT cells were treated with HSYA.Cell proliferation was detected by the cell counting kit-8 assay,and cell migration was measured using wound healing assay and Transwell migration assay.The mRNA and protein expression levels of heparin-binding epidermal growth factor(EGF)-like growth factor(HBEGF),EGF receptor(EGFR),phosphatidylinositol 3-kinase(PI3K),protein kinase B(AKT),mammalian target of rapamycin(mTOR),and hypoxia-inducible factor-1α(HIF-1α) were detected by quantitative real-time polymerase chain reaction(qRT-PCR) and Western blot,respectively.Circ_0084443-overexpressing HaCaT cells and empty plasmid HaCaT cells were constructed using the lentiviral stable transfection and treated with HSYA.The expression of circ_0084443 was detected by qRT-PCR.Results:HSYA(800 μmol/L) significantly promoted HaCaT cell proliferation and migration(P<0.05or P<0.01).It also increased the mRNA and protein expression levels of HBEGF,EGFR,PI3K,AKT,mTOR and HIF-1α,and increased the phosphorylation levels of PI3K and AKT(P<0.05 or P<0.01).Furthermore,HSYA promoted HaCaT cell proliferation and migration via the HBEGF/EGFR and PI3K/AKT/m TOR signaling pathways(P<0.01).Circ_0084443 attenuated the mRNA expression levels of HBEGF,EGFR,PI3K,AKT,mTOR and HIF-1α(P<0.05).HSYA inhibited the circ_0084443 expression,further antagonized the inhibition of circ_0084443on HBEGF,EGFR,PI3K,AKT,m TOR and HIF-1α,and promoted the proliferation of circ_0084443-overexpressing HaCaT cells(P<0.05 or P<0.01).However,HSYA could not influence the inhibitory effect of circ_0084443 on HaCaT cell migration(P>0.05).Conclusion:HSYA played an accelerative role in HaCaT cell proliferation and migration,which may be attributable to activating HBEGF/EGFR and PI3K/AKT signaling pathways,and had a particular inhibitory effect on the keratinocyte negative regulator circ_0084443.

基于网络药理学和分子对接的白藜芦醇治疗口腔鳞状细胞癌的机制研究

目的通过网络药理学及分子对接等生物学信息方法,探讨白藜芦醇治疗口腔鳞状细胞癌(oral squamous cell carcinoma,OSCC)的分子机制,为白藜芦醇治疗OSCC的临床应用提供参考。方法利用Swiss Target Prediction(http://www.swisstargetprediction.ch)、SEA数据库(http://sea.bkslab.org)、Pharm mapper数据库(http://lilab-ecust.cn)检索获得白藜芦醇的相关靶点,以DISGENET(www.disgenet.org)、OMIM(https://omim.org)、GeneCards(https://www.genecards.org)数据库筛选OSCC疾病靶点,取药物与疾病靶点的交集,再采用Cytoscape 3.7.2软件构建“药物-疾病-靶点-通路”网络,String数据库构建靶蛋白相互作用网络,采用DAVID数据库对关键蛋白进行富集分析,最后通过AutoDock及PyMOL对关键蛋白进行分子对接验证,结合富集分析和分子对接结果预测白藜芦醇治疗OSCC可能的分子作用机制;细胞水平采用Western blot检测不同浓度(50、100μmol/L)白藜芦醇对OSCC细胞株HSC-3细胞Src酪氨酸激酶(Src tyro-sine kinase,SRC)、表皮生长因子受体(epidermal growth factor receptor,EGFR)、雌激素受体基因1(estrogen receptor gene 1,ESR1)及磷脂酰肌醇三激酶/蛋白激酶B(phosphatidylinositol 3 kinase/protein kinase B,PI3K/AKT)信号通路蛋白表达的影响。结果数据库得到白藜芦醇药物靶点243个,OSCC疾病靶点6094个,将药物与疾病的靶点进行交集获得116个潜在靶点,潜在靶点主要集中参与体内蛋白质自磷酸化、肽基酪氨酸磷酸化、跨膜受体蛋白酪氨酸激酶信号通路、RNA聚合酶Ⅱ启动子转录的正调控等生物过程,干预PI3K/AKT信号通路发挥抗OSCC的作用。分子对接结果表明白藜芦醇与EGFR、ESR1、SRC等OSCC关键靶点具有较好的结合活性。细胞实验结果表明,白藜芦醇药物干预以剂量依赖的方式抑制了HSC-3细胞中SRC、EGFR、ESR1及p-PI3K和p-AKT的蛋白表达。结论白藜芦醇对OSCC细胞SRC、EGFR、ESR1、p-PI3K、p-AKT靶点具有抑制作用。

多巴胺D1受体激动剂SKF38393对剥夺血清条件下PC12细胞的保护作用

目的研究多巴胺D1受体激动剂SKF38393对剥夺血清所致PC12细胞损伤的神经保护作用及其与磷脂酰肌醇-3激酶/蛋白激酶B(phosphatidylinositol 3-kinases/protein kinase B,PI3K/Akt)、细胞外调节蛋白激酶(extracellular signal-regulated kinases,ERK)信号通路的关系。方法将PC12细胞分为血清剥夺模型组、血清剥夺后加不同剂量SKF38393处理组(1μmoL、3μmoL、10μmoL、30μmoL和100μmoL)及1%胎牛血清对照组,比较各组PC12细胞活性;PC12细胞分别加入不同剂量(同上)SKF38393处理40min,以及以10μmoLSKF38393处理不同时间(5～80min),然后检测PC12细胞的Akt473及ERK1/2的磷酸化水平;PC12细胞分别加入PI3K/Akt信号通路抑制剂LY294002(50μmoL)、ERK信号通路抑制剂PD98059(50μmoL)或PD169316(10μmoL),后再行SKF38393干预,比较各组PC12细胞活性。结果与剥夺血清组比较,10μmoLSKF38393即可显著增加PC12细胞的活性[(0.58±0.02)vs(0.37±0.01)],并且随着其剂量(30μmoL、100μmoL)的增加PC12细胞活性的增加可更明显[(0.62±0.01)、(0.65±0.02)],上述差异均有统计学意义(P<0.05)。不同剂量SKF38393和不同时间的SKF38393处理PC12细胞后磷酸化的Akt和ERK的表达水平均明显高于剥夺血清组(P<0.05)。与SKF38393组的PC12细胞活性(0.59±0.01)比较,PD169316组细胞活性(0.41±0.14)无明显差异(P>0.05),但LY294002组(0.33±0.01)和PD98059(0.33±0.03)组细胞活性均更低(P<0.05),提示仅后二者可阻断SKF38393对PC12细胞损伤的保护作用。结论 SKF38393能保护剥夺血清所致的PC12细胞损伤,其保护作用可能与激活PI3K/Akt和ERK信号通路有关。

微小核糖核酸-155对肝癌细胞增殖、侵袭迁移和凋亡的影响

目的探究微小核糖核酸(miR)-155靶向蛋白酪氨酸磷酸酶非受体21型(PTPN21)调控磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)信号通路对肝癌细胞增殖、迁移、侵袭的影响。方法体外培养Huh7人肝癌细胞并通过miR-155沉默慢病毒(sh-miR-155)转染下调miR-155。实时荧光定量聚合酶链反应(RT-qPCR)检测Huh7细胞miR-155沉默效果,获得稳转细胞株后将细胞株随机分为:Blank组(正常Huh7细胞)、shNC组(Huh7细胞+miR-155空载体)、sh-miR-155组(Huh7细胞+miR-155沉默)、sh-miR-155+Recilisib组(Huh7细胞+miR-155沉默+PI3K-AKT激动剂)、shNC+Recilisib组(Huh7细胞+miR-155空载体+PI3K-AKT激动剂)。双荧光素酶实验检测PTPN21是否为miR-155的下游;溴化噻唑蓝四氮唑(MTT)法检测各组细胞增殖能力;流式细胞术测定各组细胞凋亡水平;Transwell实验分析各组细胞侵袭与迁移能力;蛋白质印迹检测各组PTPN21、通路相关蛋白PI3K、P-PI3K、AKT、P-AKT及凋亡相关蛋白BAX、BCL-2、Caspase-3表达变化差异。结果sh-miR-155组中miR-155的表达水平低于Blank组及shNC组(P<0.0001),miR-155在Blank组及shNC组表达水平差异无统计学意义(P>0.05)。MTT结果显示,sh-miR-155组中Huh7细胞在2、3、4、5 d时A值均低于Blank组及shNC组(P<0.0001),而Blank组与shNC组差异无统计学意义(P>0.05);sh-miR-155组在2、3、4、5 d时A值低于sh-miR-155+Recilisib组及shNC+Recilisib组(P=0.0052,P<0.0001),而sh-miR-155+Recilisib组在2、3、4、5 d时A值低于shNC+Recilisib组(P<0.0001)。Blank组与shNC组迁移及侵袭细胞数差异无统计学意义(P>0.05),激活PI3K-AKT信号通路后,与Blank组相比,shNC+Recilisib组肝癌细胞的迁移、侵袭能力显著增加(P<0.0001)。相反,沉默miR-155后Huh7细胞的迁移及侵袭细胞数明显低于Blank组及shNC组(P<0.0001),而PI3K激动剂逆转了这一现象,与sh-miR-155组相比,sh-miR-155+Recilisib组肝癌细胞的迁移、侵袭能力增强(P=0.0002)。慢病毒转染Huh7人肝癌细胞以沉默miR-155,下调miR-155抑制PTPN21调控PI3K-AKT信号通路从而抑制肝癌细胞的侵袭、迁移、增殖能力,促进肝癌细胞凋亡。结论miR-155通过靶向PTPN21调控PI3K-AKT信号通路抑制肝癌细胞的迁移、侵袭、增殖。miR-155可能是未来肝癌治疗潜在靶点。

NRG4基因对胶质瘤细胞的增殖、迁移及侵袭的影响

目的探讨神经调节蛋白4(NRG4)对神经胶质瘤细胞的增殖、迁移以及侵袭作用的影响及机制。方法采用逆转录-定量聚合酶链反应(RT-qPCR)法检测神经胶质瘤患者(研究组)、对照组(同期健康志愿者)血清以及星形胶质细胞HA、神经胶质瘤细胞系U251、SHG44、LN229及T98G中NRG4和人表皮生长因子受体4(ErbB4)mRNA表达水平;将U251细胞分为Control组(空白对照)、NC组(转染不带RNA的质粒)、si-NRG4组(转染si-NRG4)和si-NRG4+ErbB4组[转染si-NRG4和ErbB4过表达质粒(pcDNA-ErbB4)]4组,通过细胞计数试剂盒-8(CCK-8)检测细胞增殖情况,划痕愈合实验和Transwell实验分析U251细胞的迁移与侵袭能力变化,免疫印迹(Western blot)检测PI3K/AKT通路中关键蛋白磷脂酰肌醇-3-激酶(PI3K)中p110α、p110β亚型、磷酸化丝氨酸/苏氨酸蛋白激酶(pAKT)中ser473和thr308 a以及蛋白激酶(AKT)表达水平。结果研究组血清中NRG4和ErbB4 mRNA表达量明显高于对照组(P<0.0001),神经胶质瘤细胞系U251中NRG4和ErbB4 mRNA相对表达量最高;与NC组比较,si-NRG4组中NRG4基因表达下调,不仅抑制U251细胞的增殖、迁移与侵袭,还降低了PI3 K-p110α,pAKT-ser473 and pAKT-thr308蛋白表达(P<0.05)。结论抑制NRG4表达可以减缓磷脂酰肌醇有关的信号通路PI3K/AKT通路的激活,抑制U251细胞的增殖和迁移,促进U251细胞凋亡,因此NRG4有可能成为治疗胶质瘤的潜在靶点。

白花蛇舌草对移植瘤肺癌小鼠肿瘤的抑制作用及对磷脂酰肌醇激酶/蛋白激酶B信号通路的影响

目的探讨白花蛇舌草(HDW)对移植瘤肺癌小鼠肿瘤的抑制作用及对磷脂酰肌醇激酶(PI3K)/蛋白激酶B(Akt)信号通路和趋化因子受体9(CCR9)、趋化因子25(CCL25)表达的影响。方法体外培养Lewis肺癌细胞株,将对数期细胞接种于C57BL/6J雄性小鼠腋下皮肤建立移植瘤模型。将造模成功的30只小鼠随机分为模型组、低剂量HDW组和高剂量HDW组,每组10只。低、高剂量HDW组小鼠分别给予HDW乙醇提取物5、20 g·kg-1,灌胃,每日1次,连续4周;模型组小鼠给予等体积的生理盐水。末次给药后称小鼠体质量,然后颈椎脱臼处死小鼠,取出瘤体测质量,并计算肿瘤体积、抑瘤率及肺脏指数。免疫组织化学法检测小鼠肺癌组织中CCR9、CCL25的表达;Western blot法检测小鼠肺癌组织中PI3K、Akt、磷酸化Akt(p-Akt)蛋白的表达。结果低剂量HDW组和模型组小鼠肺脏指数比较差异无统计学意义(P>0.05);高剂量HDW组小鼠肺脏指数显著低于模型组和低剂量HDW组(P<0.05)。高、低剂量HDW组小鼠肺癌体积和瘤体质量均显著小于模型组,抑瘤率高于模型组(P<0.05);高剂量HDW组小鼠肺癌体积和瘤体质量显著小于低剂量HDW组,抑瘤率高于低剂量HDW组(P<0.05)。高、低剂量HDW组小鼠肺癌组织中CCR9、CCL25表达量均显著低于模型组(P<0.05)。高剂量HDW组小鼠肺癌组织中CCR9、CCL25表达量显著低于低剂量HDW组(P<0.05)。高、低剂量HDW组小鼠肺癌组织中p-Akt、PI3K蛋白的表达量均显著低于模型组(P<0.05);高剂量HDW组小鼠肺癌组织中p-Akt、PI3K蛋白的表达量显著低于低剂量HDW组(P<0.05);3组小鼠肿瘤组织中Akt蛋白表达比较差异无统计学意义(P>0.05)。结论HDW可显著抑制Lewis肺癌移植瘤小鼠肿瘤的生长,降低小鼠的肺脏指数,该作用可能与其抑制CCR9/CCL25表达进而调节PI3K/Akt信号通路蛋白有关。

Molecular mechanisms of insulin resistance in type 2 diabetes mellitus

Free fatty acids are known to play a key role in promoting loss of insulin sensitivity in type 2 diabetes mellitus but the underlying mechanism is still unclear.It has been postulated that an increase in the intracellular concentration of fatty acid metabolites activates a serine kinase cascade,which leads to defects in insu-lin signaling downstream to the insulin receptor.In addition,the complex network of adipokines released from adipose tissue modulates the response of tissues to insulin.Among the many molecules involved in the intracellular processing of the signal provided by insulin,the insulin receptor substrate-2,the protein kinase B and the forkhead transcription factor Foxo 1a are of particular interest,as recent data has provided strong evidence that dysfunction of these proteins results in insulin resistance in vivo.Recently,studies have revealed that phosphoinositidedependent kinase 1-independent phosphorylation of protein kinase Cε causes a reduction in insulin receptor gene expression.Additionally,it has been suggested that mitochondrial dysfunction triggers activation of several serine kinases,and weakens insulin signal transduction.Thus,in this review,the current developments in understanding the pathophysiological processes of insulin resistance in type 2 diabetes have been summarized.In addition,this study provides potential new targets for the treatment and prevention of type 2 diabetes.

基于PI3K、Akt信号通路探讨山腊梅叶乙醇提取物的降糖降脂作用

目的观察分析山腊梅叶乙醇提取物对高脂高糖糖尿病大鼠的降糖降脂调控作用。方法将大鼠随机分为5组:正常对照组、模型组、山腊梅叶提取物低剂量组、山腊梅叶提取物高剂量组(下文简称低、高剂量组)及二甲双胍组,每组15只,除正常组大鼠外,其余大鼠采用高脂高糖饲料喂养+腹腔注射小剂量链脲佐菌素建立2型糖尿病模型。给药结束后测定各组大鼠血糖和血脂相关指标,并检测胰岛素受体底物(IRS)、磷脂酰肌醇-3激酶(PI3K)、蛋白激酶B(AKT)、葡萄糖转运体4(GLUT-4)表达水平。结果与正常对照组比较,模型组大鼠血清胰岛素水平下降,而空腹血糖、糖化血红蛋白,以及血清胆固醇(TC),三酰甘油(TG)及低密脂蛋白胆固醇(LDL-C)水平均明显升高,差异有统计学意义(P<0.05);与模型组比较,低剂量、高剂量组及二甲双胍组大鼠空腹血糖、糖化血红蛋白、血清TC、TG及LDL-C水平均明显降低,差异有统计学意义(P<0.05),血清胰岛素、肝脏IRS、PI3K、AKT、GLUT-4蛋白表达明显升高,差异有统计学意义(P<0.05)。结论山腊梅叶具有降低血糖、血脂之效,其机制可能与调节IRS-1、PI3K、Akt信号通路有关。

Treating non-small cell lung cancer by targeting the PI3K signaling pathway

The phosphosphatidylinositol-3-kinase(PI3K)signaling pathway is one of the most important intracellular signal transduction pathways affecting cell functions,such as apoptosis,translation,metabolism,and angiogenesis.Lung cancer is a malignant tumor with the highest morbidity and mortality rates in the world.It can be divided into two groups,non-small cell lung cancer(NSCLC)and small cell lung cancer(SCLC).NSCLC accounts for>85%of all lung cancers.There are currently many clinical treatment options for NSCLC;however,traditional methods such as surgery,chemotherapy,and radiotherapy have not been able to provide patients with good survival benefits.The emergence of molecular target therapy has improved the survival and prognosis of patients with NSCLC.In recent years,there have been an increasing number of studies on NSCLC and PI3K signaling pathways.Inhibitors of various parts of the PI3K pathway have appeared in various phases of clinical trials with NSCLC as an indication.This article focuses on the role of the PI3K signaling pathway in the occurrence and development of NSCLC and summarizes the current clinical research progress and possible development strategies.