Roles of phosphatidylinositol-3-kinases signaling pathway in inflammation-related cancer:Impact of rs10889677 variant and buparlisib in colitis-associated cancer

BACKGROUND Phosphatidylinositol-3-kinases(PI3K)is a well-known route in inflammationrelated cancer.Recent discovery on PI3K-related genes revealed a potential variant that links ulcerative colitis(UC)and colorectal cancer(CRC)with colitisassociated cancer(CAC).PI3K/AKT pathway has been recommended as a potential additional therapeutic option for CRC due to its substantial role in modifying cellular processes.Buparlisib is a pan-class I PI3K inhibitor previously shown to reduce tumor growth.AIM To investigate the regulation of rs10889677 and the role of buparlisib in the PI3K signaling pathway in CAC pathogenesis.METHODS Genomic DNA from 32 colonic samples,including CAC(n=7),UC(n=10)and CRC(n=15),was sequenced for the rs10889677 mutation.The mutant and wildtype fragments were amplified and cloned in the pmirGLO vector.The luciferase activity of cloned vectors was assessed after transfection into the HT29 cell line.CAC mice were induced by a mixture of a single azoxymethane injection and three cycles of dextran sulphate sodium,then buparlisib was administered after 14 d.The excised colon was subjected to immunohistochemistry for Ki67 and Cleaved-caspase-3 markers and quantitative real-time polymerase chain reaction analysis for Pdk1 and Sgk2.RESULTS Luciferase activity decreased by 2.07-fold in the rs10889677 mutant,confirming the hypothesis that the variant disrupted miRNA binding sites,which led to an increase in IL23R expression and the activation of the PI3K signaling pathway.Furthermore,CAC-induced mice had a significantly higher disease activity index(P<0.05).Buparlisib treatment significantly decreased mean weight loss in CAC-induced mice(P<0.05),reduced the percentage of proliferating cells by 5%,and increased the number of apoptotic cells.The treatment also caused a downward trend of Pdk1 expression and significantly decreased Sgk2 expression.CONCLUSION Our findings suggested that the rs10889677 variant as a critical initiator of the PI3K signaling pathway,and buparlisib had the ability to prevent PI3K-non-AKT activation in the pathophysiology of CAC.

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.

Herbal cake-partitioned moxibustion inhibits colonic autophagy in Crohn’s disease via signaling involving distinct classes of phosphatidylinositol 3-kinases

BACKGROUND Autophagy is an evolutionarily conserved biological process in eukaryotic cells that involves lysosomal-mediated degradation and recycling of related cellular components.Recent studies have shown that autophagy plays an important role in the pathogenesis of Crohn’s disease(CD).Herbal cake-partitioned moxibustion(HM)has been historically practiced to treat CD.However,the mechanism by which HM regulates colonic autophagy in CD remains unclear.AIM To observe whether HM can alleviate CD by regulating colonic autophagy and to elucidate the underlying mechanism.METHODS Rats were randomly divided into a normal control(NC)group,a CD group,an HM group,an insulin+CD(I+CD)group,an insulin+HM(I+HM)group,a rapamycin+CD(RA+CD)group,and a rapamycin+HM(RA+HM)group.2,4,6-trinitrobenzenesulfonic acid was administered to establish a CD model.The morphology of the colonic mucosa was observed by hematoxylin-eosin staining,and the formation of autophagosomes was observed by electron microscopy.The expression of autophagy marker microtubule-associated protein 1 light chain 3 beta(LC3B)was observed by immunofluorescence staining.Insulin and rapamycin were used to inhibit and activate colonic autophagy,respectively.The mRNA expression levels of phosphatidylinositol 3-kinase class I(PI3KC1),Akt1,LC3B,sequestosome 1(p62),and mammalian target of rapamycin(mTOR)were evaluated by RT-qPCR.The protein expression levels of interleukin 18(IL-18),tumor necrosis factor-α(TNF-α),nuclear factorκB/p65(NF-κB p65),LC3B,p62,coiled-coil myosin-like BCL2-interacting protein(Beclin-1),p-mTOR,PI3KC1,class III phosphatidylinositol 3-kinase(PI3KC3/Vps34),and p-Akt were evaluated by Western blot analysis.RESULTS Compared with the NC group,the CD group showed severe damage to colon tissues and higher expression levels of IL-18 and NF-κB p65 in colon tissues(P<0.01 for both).Compared with the CD group,the HM group showed significantly lower levels of these proteins(PIL-18<0.01 and Pp65<0.05).There were no significant differences in the expression of TNF-αprotein in colon tissue among the rat groups.Typical autophagic vesicles were found in both the CD and HM groups.The expression of the autophagy proteins LC3B and Beclin-1 was upregulated(P<0.01 for both)in the colon tissues of rats in the CD group compared with the NC group,while the protein expression of p62 and p-mTOR was downregulated(P<0.01 for both).However,these expression trends were significantly reversed in the HM group compared with the CD group(PLC3B<0.01,PBeclin-1<0.05,Pp62<0.05,and Pm-TOR<0.05).Compared with those in the RA+CD group,the mRNA expression levels of PI3KC1,Akt1,mTOR,and p62 in the RA+HM group were significantly higher(PPI3KC1<0.01 and PAkt1,mTOR,and p62<0.05),while those of LC3B were significantly lower(P<0.05).Compared with the RA+CD group,the RA+HM group exhibited significantly higher PI3KC1,p-Akt1,and pmTOR protein levels(PPI3KC1<0.01,Pp-Akt1<0.05,and Pp-mTOR<0.01),a higher p62 protein level(P=0.057),and significantly lower LC3B and Vps34 protein levels(P<0.01 for both)in colon tissue.CONCLUSION HM can activate PI3KC1/Akt1/mTOR signaling while inhibiting the PI3KC3(Vps34)-Beclin-1 protein complex in the colon tissues of CD rats,thereby inhibiting overactivated autophagy and thus exerting a therapeutic effect.

Analysis of Phosphatidylinositol 3-kinase Activation in the Adipose Tissue of Gestational Diabetes Mellitus Patients and Insulin Resistance

The P85 regulatory subunit protein and gene expression and P110 catalylic subunit activity of phosphatidylinositol 3-kinase (PI-3K) were investigated in adipose tissue of patients with gestational diabetes mellitus (GDM) in order to explore the molecular mechanisms of insulin resistance (IR) of GDM. Samples from patients with GDM (n=50), and controls (n=50) were collected. Fasting insulin (FIN) was determined by radioimmunoassay. Fasting plasma glucose (FPG) was measured by oxidase assay. Western blot technique was used to detect the levels of PI-3K P85 subunit in adipose tissues of patients with GDM. The mRNA expression of PI-3K P85 subunit was detected by reverse transcription polymerase chain reaction (RT-PCR) method in the adipose tissue. PI-3K activity was examined by immunoprecipitation, thin-layer chromatography and gamma scintillation counting. The results were analyzed statistically. It was found that the levels of FPG, FIN and HOMA-IR in GDM group were significantly higher than those in control group (all P0.05). PI-3K activity was significantly decreased to 82.89% in GDM group as compared with control group (P<0.01) and negatively correlated with HOMA-IR (r=-0.75, P<0.01). It was concluded that PI-3K in GDM patients may be involved in the insulin signaling pathway, resulting in IR of GDM.

Phosphatidylinositol 3-kinase CB association with preoperative radiotherapy response in rectal adenocarcinoma

AIM:To examine the correlation of phosphatidylinositol3-kinase(PIK3)CB expression with preoperative radiotherapy response in patients with stageⅡ/Ⅲrectal adenocarcinoma.METHODS:PIK3CB immunoexpression was retrospectively assessed in pretreatment biopsies from 208 patients with clinical stageⅡ/Ⅲrectal adenocarcinoma,who underwent radical surgery after 30-Gy/10-fractionpreoperative radiotherapy.The relation between PIK3CB expression and tumor regression grade,clinicopathological characteristics,and survival time was statistically analyzed.Western blotting and in vitro clonogenic formation assay were used to detect PIK3CB expression in four colorectal cancer cell lines(HCT116,HT29,Lo Vo,and LS174T)treated with 6-Gy ionizing radiation.Pharmacological assays were used to evaluate the therapeutic relevance of TGX-221(a PIK3CB-specific inhibitor)in the four colorectal cancer cell lines.RESULTS:Immunohistochemical staining indicated that PIK3CB was more abundant in rectal adenocarcinoma tissues with poor response to preoperative radiotherapy.High expression of PIK3CB was closely correlated with tumor height(P<0.05),yp T stage(P<0.05),and high-degree tumor regression grade(P<0.001).High expression of PIK3CB was a potential prognostic factor for local recurrence-free survival(P<0.05)and metastasis-free survival(P<0.05).High expression of PIK3CB was also associated with poor therapeutic response and adverse outcomes in rectal adenocarcinoma patients treated with 30-Gy/10-fraction preoperative radiotherapy.In vitro,PIK3CB expression was upregulated in all four colorectal cancer cell lines concurrently treated with 6-Gy ionizing radiation,and the PIK3CB-specific inhibitor TGX-221 effectively inhibited the clonogenic formation of these four colorectal cancer cell lines.CONCLUSION:PIK3CB is critically involved in response to preoperative radiotherapy and may serve as a novel target for therapeutic intervention.

Micro RNA-21 promotes phosphatase gene and protein kinase B/phosphatidylinositol 3-kinase expression in colorectal cancer

AIM: To explore the regulatory mechanism of the target gene of micro RNA-21(mi R-21), phosphatase gene(p TEN), and its downstream proteins, protein kinase B(AKT) and phosphatidylinositol 3-kinase(p I3K), in colorectal cancer(CRC) cells. METHODS: Quantitative real-time p CR(q RT-p CR) and Western blot were used to detect the expression levels of mi R-21 and p TEN in HCT116, HT29, Colo32 and SW480 CRC cell lines. Also, the expression levels of p TEN m RNA and its downstream proteins AKT and p I3 K in HCT116 cells after downregulating mi R-21 were investigated. RESULTS: Comparing the mi R-21 expression in CRC cells, the expression levels of mi R-21 were highest in HCT116 cells, and the expression levels of mi R-21 were lowest in SW480 cells. In comparing mi R-21 and p TEN expression in CRC cells, we found that the protein expression levels of mi R-21 and p TEN were inversely correlated(p < 0.05); when mi R-21 expression was reduced, m RNA expression levels of p TEN did not significantly change(p > 0.05), but the expression levels of its protein significantly increased(p < 0.05). In comparing the levels of p TEN protein and downstream AKT and p I3 K in HCT116 cells after downregulation of mi R-21 expression, the levels of AKT and p I3 K protein expression significantly decreased(p < 0.05). CONCLUSION: p TEN is one of the direct target genesof mi R-21. Thus, phosphatase gene and its downstream AKT and p I3 K expression levels can be regulated by regulating the expression levels of mi R-21, which in turn regulates the development of CRC.

Phosphatidylinositol 3-kinase/Akt pathway regulates hepatic stellate cell apoptosis

AIM: To investigate the role of phosphatidylinositol 3-kinase (PI 3-K)/Akt signaling pathway in the balance of HSC activation and apoptosis in rat hepatic stellate cells (HSC). METHODS: An activated HSC cell line was used in this study. LY 294002, the PI 3-K/Akt signal pathway block-er was used to investigate the molecular events on apoptosis in HSC and to interpret the role of this path-way in HSC apoptosis. Immunocytochemistry, Western blot and reverse transcription polymerase chain reac-tion (RT-PCR) analysis were applied to detect the ex-pression of PI 3-K, and simultaneously phosphorylated-Akt (p-Akt) and total-Akt were determined by Western blot. The HSC apoptosis was examined by annexin-V/ propidium iodide double-labelled flow cytometry and transmission electron microscopy. RESULTS: The apoptosis rates in LY 294002 (30.82% ± 2.90%) and LY 294002 + PDGF-BB (28.16% ± 2.58%) groups were signif icantly increased compared with those of control (9.02% ± 1.81%) and PDGF-BB (4.35% ± 1.18%). PDGF-BB augmented PI 3-K and p-Akt expres-sion. LY 294002 signif icantly reduced the contents of PI 3-K and p-Akt. mRNA transcription evaluated by RT-PCR showed similar tendencies as protein expression. CONCLUSION: Inhibition of PI 3-K/Akt signaling path-way induces apoptosis in HSC.

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.

Alisol B acetate induces apoptosis of SGC7901 cells via mitochondrial and phosphatidylinositol 3-kinases/Akt signaling pathways

AIM: To examine the effect of alisol B acetate on the growth of human gastric cancer cell line SGC7901 and its possible mechanism of action. METHODS: The cytotoxic effect of alisol B acetate on SGC7901 cells was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Phase-contrast and electron microscopy were used to observe the morphological changes. Cell cycle and mitochondrial transmembrane potential (△Ψm) were determined by flow cytometry. Western blotting was used to detect the expression of apoptosis-regulated gene Bcl-2, Bax, Apaf-1, caspase-3, caspase-9, Akt, P-Akt and phosphatidylinositol 3-kinases (PI3K). RESULTS: Alisol B acetate inhibited the proliferation of SGC7901 cell line in a time-and dose-dependent manner. PI staining showed that alisol B acetate can change the cell cycle distribution of SGC7901, increase the proportion of cells in G0-G1 phase and decrease the proportion of S phase cells and G2-M phase cells. Alisol B acetate at a concentration of 30 μmol/L induced apoptosis after 24, 48 and 72 h incubation, with occurrence rates of apoptotic cells of 4.36%, 14.42% and 21.16%, respectively. Phase-contrast and electron microscopy revealed that the nuclear fragmentation and chromosomal condensed, cells shrank and attachment loss appeared in the SGC7901 treated with alisol B acetate. Apoptosis of SGC7901cells was associated with cell cycle arrest, caspase-3 and caspase-9 activation, loss of mitochondrial membrane potential and up-regulation of the ratio of Bax/Bcl-2 and inhibition of the PI3K/Akt. CONCLUSION: Alisol B acetate exhibits an antiproliferative effect in SGC7901 cells by inducing apoptosis. Apoptosis of SGC7901 cells involves mitochondria-caspase and PI3K/Akt dependent pathways.

Alterations in the human epidermal growth factor receptor 2-phosphatidylinositol 3-kinase-v-Akt pathway in gastric cancer

AIM:To investigate human epidermal growth factor receptor 2(HER2)-phosphatidylinositol 3-kinase(PI3K)-vAkt murine thymoma viral oncogene homolog signaling pathway.METHODS:We analyzed 231 formalin-fixed,paraffinembedded gastric cancer tissue specimens from Japanese patients who had undergone surgical treatment.The patients' age,sex,tumor location,depth of invasion,pathological type,lymph node metastasis,and pathological stage were determined by a review of the medical records.Expression of HER2 was analyzed by immunohistochemistry(IHC) using the HercepTest TM kit.Standard criteria for HER2 positivity(0,1+,2+,and 3+) were used.Tumors that scored 3+ were considered HER2-positive.Expression of phospho Akt(pAkt) was also analyzed by IHC.Tumors were considered pAkt-positive when the percentage of positive tumor cells was 10% or more.PI3K,catalytic,alpha polypeptide(PIK3CA) mutations in exons 1,9 and 20 were analyzed by pyrosequencing.Epstein-Barr virus(EBV) infection was analyzed by in situ hybridization targeting EBV-encoded small RNA(EBER) with an EBER-RNA probe.Microsatellite instability(MSI) was analyzed by polymerase chain reaction using the mononucleotide markers BAT25 and BAT26.RESULTS:HER2 expression levels of 0,1+,2+ and 3+ were found in 167(72%),32(14%),12(5%) and 20(8.7%) samples,respectively.HER2 overexpression(IHC 3+) significantly correlated with intestinal histological type(15/20 vs 98 /205,P = 0.05).PIK3CA mutations were present in 20 cases(8.7%) and significantly correlated with MSI(10/20 vs 9/211,P < 0.01).The mutation frequency was high(21%) in T4 cancers and very low(6%) in T2 cancers.Mutations in exons 1,9 and 20 were detected in 5(2%),9(4%) and 7(3%) cases,respectively.Two new types of PIK3CA mutation,R88Q and R108H,were found in exon1.All PIK3CA mutations were heterozygous missense singlebase substitutions,the most common being H1047R(6/20,30%) in exon20.Eighteen cancers(8%) were EBV-positive and this positivity significantly correlated with a diffuse histological type(13/18 vs 93/198,P = 0.04).There were 7 cases of lymphoepithelioma-like carcinomas(LELC) and 6 of those cases were EBV-positive(percent/EBV:6/18,33%;percent/all LELC:6/7,86%).pAkt expression was positive in 119(53%) cases but showed no correlation with clinicopathological characteristics.pAkt expression was significantly correlated with HER2 overexpression(16/20 vs 103/211,P < 0.01) but not with PIK3CA mutations(12/20 vs 107/211,P = 0.37) or EBV infection(8/18 vs 103/211,P = 0.69).The frequency of pAkt expression was higher in cancers with exon20 mutations(100%) than in those with exon1(40%) or exon9(56%) mutations.One case showed both HER2 overexpression and EBV infection and 3 cases showed both PIK3CA mutations and EBV infection.However,no cases showed both PIK3CA mutations and HER2 overexpression.One EBVpositive cancer with PIK3CA mutation(H1047R) was MSI-positive.Three of these 4 cases were positive for pAkt expression.In survival analysis,pAkt expression significantly correlated with a poor prognosis(hazard ratio 1.75;95%CI:1.12-2.80,P = 0.02).CONCLUSION:HER2 expression,PIK3CA mutations and EBV infection in gastric cancer were characterized.pAkt expression significantly correlates with HER2 expression and with a poor prognosis.

Glycine-extended gastrin activates two independent tyrosine-kinases in upstream of p85/p110 phosphatidylinositol 3-kinase in human colonic tumour cells

瞄准：为了调查 Src， JAK2 和 phosphatidylinositol 3-kinase (PI3K ) 小径是否涉及人的结肠的瘤房间的增长，由扩大 glycine 的促胃液素导致了(G-gly ) ，先锋在 ated 促胃液素中并且到成熟阐明在响应这肽的这三家族 ases 之间的分子的相互作用。方法：用人的结肠的瘤，房间作为一个模型衬里 HCT116，我们首先测量了 PI3K， p60-Src 和 JAK2 的激活响应 G-gly 由在试管内激酶试金。然后，我们由 MTT 测试在 G-gly-induced 房间增长调查了这些家族 ases 的参与。结果：G-gly，刺激在 HCT116 导致了 p60-Src， JAK2 和 PI3K 激活。不同小径涉及房间导致了由的人的结肠癌的增长 G-gly。而且，我们发现 Src 和 JAK2 对由这肽的 PI3K 规定必要。然而，我们没发现在二酷氨酸家族 ases 之间的任何串音。结论：我们的结果建议 p60-Src/PI3K 和 JAK2/PI3K 小径独立地行动调停人的结肠的瘤房间上的 G-gly 增生的的效果。

Anti-silencing function 1B knockdown suppresses the malignant phenotype of colorectal cancer by inactivating the phosphatidylinositol 3-kinase/AKT pathway

BACKGROUND Mounting studies have highlighted the pivotal influence of anti-silencing function 1B(ASF1B)on the malignancy of cancers.AIM To explore the influence and mechanism of ASF1B in colorectal cancer(CRC).METHODS Quantitative real-time polymerase chain reaction(qRT-PCR)was used to detect mRNA expression of ASF1B.Immunohistochemical staining was performed to detect protein expression of ASF1B and Ki67 in tumor tissues.Western blot analysis was used to determine levels of ASF1B and proliferation/epithelial mesenchymal transition(EMT)/stemness-related proteins.In addition,the proliferation of CRC cells was assessed using Cell Counting Kit-8 and 5-Ethynyl-2’-Deoxyuridine assays.The migration and invasion of CRC cells were evaluated using transwell assays.Stemness of CRC cells was tested using the sphere formation assay.To construct a xenograft tumor model,HCT116 cells were introduced into mouse flanks via subcutaneous injection.RESULTS ASF1B expression was markedly increased in CRC tissues and cells,and it was inversely correlated with overall survival of CRC patients and was positively associated with the tumor node metastasis(TNM)stage of CRC patients.Silencing of ASF1B suppressed proliferation,migration,invasion,stemness and EMT of CRC cells as well as tumorigenesis of xenograft mice.Furthermore,protein levels of Pphosphatidylinositol 3-kinase(p-PI3K)and p-AKT were decreased after silencing of ASF1B in CRC cells.The inhibitory effects of ASF1B knockdown on cell proliferation,stemness and EMT were partly abolished by PI3K activator in CRC cells.CONCLUSION Silencing of ASF1B inactivated the PI3K/AKT pathway to suppress CRC malignancy in vitro.

Telencephalin protects PAJU cells from amyloid beta protein-induced apoptosis by activating the ezrin/radixin/moesin protein family/phosphatidylinositol-3-kinase/protein kinase B pathway

Telencephalin is a neural glycoprotein that reduces apoptosis induced by amyloid beta protein in the human neural tumor cell line PAJU. In this study, we examined the role of the ezrin/radixin/moesin protein family/phosphatidylinositol-3-kinase/protein kinase B pathway in this process. Western blot analysis demonstrated that telencephalin, phosphorylated ezrin/radixin/moesin and phosphatidylinositol-3-kinase/protein kinase B were not expressed in PAJU cells transfected with empty plasmid, while they were expressed in PAJU cells transfected with a telencephalin expression plasmid. After treatment with 1.0 nM amyloid beta protein 42, expression of telencephalin and phosphorylated phosphatidylinositol-3-kinase/protein kinase B in the transfected cells gradually diminished, while levels of phosphorylated ezrin/radixin/moesin increased. In addition, the high levels of telencephalin, phosphorylated ezrin/radixin/moesin and phosphatidylinositol-3-kinase/protein kinase B expression in PAJU cells transfected with a telencephalin expression plasmid could be suppressed by the phosphatidylinositol-3-kinase inhibitor LY294002. These findings indicate that telencephalin activates the ezrin/radixin/moesin family/phosphatidylinositol-3-kinase/protein kinase B pathway and protects PAJU cells from amyloid beta protein-induced apoptosis.

Response of Subcutaneous Xenografts of Endometrial Cancer in Nude Mice to Inhibitors of Phosphatidylinositol 3-Kinase/Akt and Mitogen-Activated Protein Kinase (MAPK) Pathways: An Effective Therapeutic Strategy for Endometrial Cancer

Objective: This study was designed to explore whether inhibition of the extracellular-regulated kinase (ERK) and phosphatidylinositol-3-kinase (PI3K) signaling pathways can inhibit the growth of xenografts of endometrial cancer cell lines with different estrogen receptors (ER) profiles in vivo and to provide preliminary laboratory basis for the probability of endometrial adenocarcinoma treatment with blockage of the two pathways, especially to endometrial cancer with low ER status. Methods: Human endometrial cancer Ishikawa bearing ER and HEC-1Awith low ER status cells were subcutaneously injected into BALB/c nude mice to establish endometrial cancer xenograft tumor models. The effects of PI3K/Akt inhibitor LY294002, MAPK/ERK1/2 inhibitor PD-98059 and their combinations on the growth of the xenograft tumors and apoptotic state of Ishikawa and HEC-1Acells were tested in vivo using the inhibitory rate, the terminal deoxynucleotidyl transferase-mediated nick-end labeling assay, H/E-stain. Western blot analysis was used to detect the alterations of activated ERK (P-ERK) and AKT (P-AKT) during this process. Results: LY294002, a PI3K/Akt pathway inhibitor, induced significant suppression in the growth of both Ishikawa and HEC-1Acell xenograft tumors, concomitant with increased apoptosis in xenografts as evidenced by TUNEL. A similar effect was also observed when the MAPK/ERK1/2 signaling pathway was inhibited by PD98059. Concurrent inhibition of the PI3K/Akt and MAPK/ERK1/2 pathways showed enhanced anti-tumor effects in vivo as indicated by increased apoptosis. At the same time, the levels of P-ERK and P-AKT in both xenograft tumors decreased, and their levels in combination group was the lowest. Conclusions: PD98059, LY294002 and their combinations showed remarkable inhibitory effects on xenograft tumors of endometrial carcinoma cell lines with different expression status of ER in vivo through blockage of PI3K/Akt and MAPK/ERK1/2 signaling pathways. This suggests that targeting these pathways may be an effective therapeutic strategy against endometrial carcinomas, especially for ER-negative cancers which show poor response to endocrinal therapy.

PI3K信号过度活化引发免疫病理机制研究进展

目前少数研究发现磷脂酰肌醇3-激酶(PI3K)基因PIK3CD(编码p110δ)发生功能获得性(GOF)变异后,可导致活化的PI3Kδ综合征(APDS)。该突变可通过诱导T细胞减少/衰老/耗竭、B细胞发育受阻、NK细胞毒性降低等多种免疫系统内部缺陷机制导致机体内免疫缺陷、免疫失调甚至肿瘤发生。本文主要对PI3Kδ GOF诱导APDS发生的相关临床疾病特点及免疫缺陷分子机制展开综述,重点阐述该突变导致淋巴细胞发育、分化及功能缺陷的分子机制。

基于PI3K/AKT/GSK-3β信号通路探讨EA改善APP/PS1双转基因小鼠认知功能障碍的内在机制

目的探讨鞣花酸(ellagicacid,EA)对APP/PS1双转基因小鼠认知功能的影响,并基于磷脂酰肌醇3-激酶/蛋白激酶B/糖原合成酶激酶-3(PI3K/AKT/GSK-3β)信号通路探讨鞣花酸对双转基因小鼠海马氧化应激水平的调节机制。方法将32只SPF级6月龄APP/PS1双转基因小鼠随机分为4组,即APP/PS1组、APP/PS1+EA组、APP/PS1+LY294002组、APP/PS1+EA+LY294002组,每组8只,另外选取8只SPF级C57BL/6J野生型小鼠(Wildtype)作为空白对照组,即WT组。APP/PS1+EA组给予50mg·kg^(-1)·d^(-1)灌胃EA;APP/PS1+LY294002组予以1.5mg·kg^(-1)·d^(-1)腹腔注射PI3K抑制剂LY294002;APP/PS1+EA+LY294002组予以50mg·kg^(-1)·d^(-1)灌胃EA,同时按1.5mg·kg^(-1)·d^(-1)腹腔注射LY294002;WT组和APP/PS1组于相同时间点灌胃等体积10%二甲基亚砜(DMSO)。每日给药1次,连续给药60天。Morris水迷宫检测小鼠学习和记忆能力,免疫组化、蛋白免疫印迹法检测PI3K、AKT、GSK-3β相关蛋白的表达,透射电镜观察小鼠海马组织超微结构变化。结果与WT组相比,其他四组的逃避潜伏期均增长(P<0.05),穿越平台次数明显减少(P<0.01);APP/PS1组、APP/PS1+LY294002组和APP/PS1+EA+LY294002组中的PI3K、AKT蛋白表达量显著降低(P<0.01),GSK-3β表达量显著升高(P<0.01);APP/PS1+EA组的PI3K表达量降低(P<0.05),AKT表达量显著降低(P<0.01),GSK-3β表达量升高(P<0.05);与WT组相比,APP/PS1组海马神经元细胞数目较少,线粒体结构破坏,大部分线粒体出现肿胀,线粒体的内膜和外模不完整,部分线粒体嵴消失,微管、微丝缠结,排列紊乱,而APP/PS1+EA组神经元细胞数较APP/PS1组增多,线粒体结构较清晰,可见清楚的线粒体嵴,线粒体轻度水肿。微管、微丝排列较整齐有序。结论鞣花酸改善AD模型小鼠的学习和记忆能力、减少海马神经元细胞损伤和凋亡,其作用机制可能是通过调节PI3K、AKT、GSK-3β等相关蛋白降低AD模型小鼠海马氧化应激水平。

miR-93-5p通过PI3K/AKT通路调控HepG2细胞自噬

目的:探究miR-93-5p对HepG2细胞增殖、自噬、葡萄糖消耗以及磷脂酰肌醇3-激酶(phosphatidylinositol 3-kinases,PI3K)/蛋白激酶B(protein kinase B,AKT)通路的影响。方法:高浓度葡萄糖诱导构建胰岛素抵抗(insulin resistance,IR)细胞模型,设计合成miR-93-5p inhibitor和NC,结合自噬抑制剂3-MA,将细胞分为Control组、IR组、IR+inhibitor NC组、IR+inhibitor组、IR+3-MA+inhibitor组。CCK8法检测各组细胞增殖活力,试剂盒检测各组细胞葡萄糖消耗量和细胞糖原合成情况,Western-Blot法检测细胞自噬基因微管相关蛋白1轻链3(autophagy genes microtubule-associated protein 1 light chain 3,LC3)-I、LC3-II、肝细胞生长因子(hepatocyte growth factor,HGF)蛋白、PI3K/AKT通路蛋白(AKT、p-AKT)的表达。结果:与对照组相比,IR组细胞增殖活力、葡萄糖消耗量和细胞糖原合成量、HGF蛋白、LC3-II蛋白表达下降(P<0.01),LC3-I蛋白和p-AKT/AKT值表达均增加(P<0.01)。与IR组和IR+inhibitor NC组相比,IR+inhibitor组细胞增殖活力、葡萄糖消耗量和细胞糖原合成量、HGF蛋白、LC3-II蛋白表达增加(P<0.01),LC3-I蛋白和p-AKT/AKT值表达均下降(P<0.01)。与IR+inhibitor组相比,3-MA能逆转miR-93-5p inhibitor的作用。结论:miR-93-5p通过PI3K/AKT通路促进HepG2细胞自噬,进而抑制胰岛素抵抗,缓解糖尿病造成的机体损伤。

积雪草酸调节PI3K/AKT信号通路对七氟烷诱导的海马神经元HT-22细胞凋亡的影响

目的探讨积雪草酸(AA)通过调节磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/AKT)信号通路对七氟烷(SEVO)诱导的HT-22细胞凋亡的影响。方法使用不同浓度(0、5、10、15、20、30μmol/L)AA处理七氟烷诱导HT-22细胞24 h,CCK-8检测HT-22细胞活力;将HT-22细胞分为对照(Control)组、七氟烷(SEVO)组、AA低浓度(AA-L,10μmol/L)组、AA中浓度(AA-M,15μmol/L)组、AA高浓度(AA-H,20μmol/L)组和AA高浓度+PI13K通路抑制剂LY294002(AA-H+LY294002,20μmol/L AA+5μmol/L LY294002)组。显微镜下观察各组细胞形态变化,ELISA检测炎性因子肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)及氧化应激指标超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和丙二醛(MDA)水平,活性氧(ROS)试剂盒检测ROS水平,TUNEL试剂盒检测HT-22凋亡,JC-1法检测线粒体膜电位,三磷酸腺苷(ATP)含量检测试剂盒检测ATP含量,Western blot检测B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、半胱氨酸天冬氨酸蛋白酶-3(Caspase-3)、p-PI3K、PI3K、p-AKT和AKT蛋白表达。结果与0μmol/L相比,5~30μmol/L AA处理的HT-22细胞活力呈浓度依赖性升高(P<0.05),选择浓度为10、15、20μmol/L的AA用于后续实验。与SEVO组相比,AA-L组、AA-M组和AA-H组TNF-α、IL-6、MDA和ROS水平、细胞凋亡率、Bax和Caspase-3蛋白表达降低,SOD和GSH-Px水平、红/绿JC-1荧光比、ATP含量、Bcl-2蛋白表达、PI3K和AKT磷酸化水平增加(P<0.05),且呈浓度依赖性。LY294002可逆转AA对七氟烷诱导的HT-22细胞损伤的保护作用(P<0.05)。结论AA通过激活PI3K/AKT信号通路保护七氟烷诱导的HT-22细胞损伤,为新型减轻七氟烷诱导的神经毒性的药物开发提供了一定的理论参考。

Yes相关蛋白(YAP)通过激活PI3K/AKT通路促进皮肤鳞状细胞癌细胞侵袭和迁移

目的探讨Yes相关蛋白(YAP)在皮肤鳞状细胞癌(cSCC)中表达及与cSCC侵袭和迁移中的作用。方法通过免疫组织化学染色法检测cSCC、鲍温病(BD)、癌旁正常皮肤组织中YAP的表达水平,并分析与临床病理参数之间的关系;利用慢病毒转染构建YAP基因敲低的A431稳定细胞株,利用四甲基罗丹明标记的鬼笔环肽检测A431细胞微丝分布和数量,Transwell TM实验检测细胞侵袭能力,划痕实验检测A431细胞的迁移能力;免疫荧光细胞化学染色法观察敲低YAP后上皮间质转化(EMT)相关标志物上皮钙黏素(E-cadherin)、锌指转录因子Snail的表达;Western blot法检测E-cadherin、Snail、β-catenin、磷脂酰肌醇3激酶(PI3K)、蛋白激酶B(AKT)、磷酸化的蛋白激酶B(p-AKT)、核糖体蛋白S6(S6)、磷酸化S6(p-S6)、4E结合蛋白1(4EBP1)、磷酸化的4EBP1(p-4EBP1)的表达。结果YAP在cSCC和BD中表达显著高于癌旁正常皮肤组织;cSCC中YAP高表达与肿瘤大小、分化程度、侵袭程度密切相关,与患者的性别、年龄、发病部位、形态类型、是否神经脉管侵犯不相关;敲低A431细胞中YAP后,肿瘤细胞的侵袭、迁移能力降低,细胞微丝变细、伪足变少;E-cadherin表达增加,Snail和β-catenin蛋白表达降低,p-AKT、p-S6及p-4EBP1蛋白表达降低。结论YAP在cSCC中高表达,YAP激活PI3K/AKT信号通路促进cSCC的侵袭、迁移及EMT过程。

黄芪阳和汤调控PI3K/AKT/NF-κB信号通路促进糖尿病足溃疡大鼠创面愈合

目的基于磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)/核因子-κB(NF-κB)信号通路探究黄芪阳和汤对糖尿病足溃疡(DFU)大鼠创面愈合的影响。方法构建DFU大鼠模型,将建模成功的48只大鼠随机分为模型组,黄芪阳和汤低(8.5 g/kg)、高(17 g/kg)剂量组,黄芪阳和汤高剂量(17 g/kg)+LY294002(PI3K/AKT通路抑制剂,0.3 mg/kg)组;每组12只;另取12只大鼠为对照组。各组大鼠给予对应药物干预,连续4周。第14、28天给药后,观察大鼠一般状态及创面变化,计算创面愈合率,检测大鼠空腹血糖(FBG)水平和大鼠创面周围组织经皮氧分压(TcpO2);酶联免疫吸附试验检测大鼠血清血管内皮生长因子(VEGF)、缺氧诱导因子-1α(HIF-1α)、C反应蛋白(CRP)、白细胞介素(IL)-6水平;苏木素-伊红染色观察大鼠创面组织病理学变化;免疫组织化学染色测定大鼠创面组织微血管密度;蛋白免疫印迹法检测大鼠创面组织中PI3K、磷酸化PI3K(p-PI3K)、AKT、磷酸化AKT(p-AKT)、NF-κB p65、磷酸化NF-κB p65(p-NF-κB p65)、NF-κB抑制蛋白α(IκB-α)蛋白表达。结果对照组大鼠毛色光滑,饮食、饮水、排泄均正常,较活跃,创面愈合快,创面组织炎症反应较轻,新生血管较多,肉芽组织中成纤维细胞及胶原基质丰富;模型组大鼠毛色暗淡无光泽,活动减少,且出现多饮、多食、多尿症状,创面颜色较深,且周围组织出现水肿、溃疡,创面组织可见大量炎性细胞浸润,伴组织坏死、渗出,新生血管及成纤维细胞较少,创面愈合率、创面周围组织TcpO2、血清VEGF、HIF-1α、创面组织微血管密度、p-PI3K、p-AKT、IκB-α蛋白表达水平降低,FBG、血清CRP、IL-6、创面组织p-NF-κB p65蛋白表达升高(P<0.05);与模型组相比,黄芪阳和汤低、高剂量组大鼠状态逐渐改善,创面组织病变程度依次减轻,创面愈合率、创面周围组织TcpO2、血清VEGF、HIF-1α、创面组织微血管密度、p-PI3K、p-AKT、IκB-α蛋白表达水平依次升高,FBG、血清CRP、IL-6、创面组织p-NF-κB p65蛋白表达依次降低(P<0.05);LY294002能部分逆转高剂量黄芪阳和汤对DFU大鼠的治疗作用(P<0.05)。结论黄芪阳和汤能调控PI3K/AKT/NF-κB信号通路,抑制DFU大鼠炎症反应,促进血管新生,从而促进创面愈合。