Tumor-related factor complement Clq/TNF-related protein 6 affects the development of digestive system tumors through the phosphatidylinositol 3-kinase pathway

In this editorial,we review the work of Razali et al published in World J Gas-troenterology,with a particular focus on the effect of rs10889677 variation in the phosphatidylinositol 3-kinase(PI3K)pathway and buparlisib on colitis-associated cancer.The role of PI3K in promoting cancer progression has been widely recognized,as it is involved in regulating the survival,differentiation,and prolif-eration of cancer cells.The complement Clq/TNF-related protein 6(CTRP6)is a newer tumor-associated factor.Recent studies have revealed the pro-tumor effect of CTRP6 in gastric cancer,hepatocellular carcinoma,colorectal cancer,and other gastrointestinal tumors through the PI3K pathway.This article attempts to reveal the mechanism through which the CTRP6 affects the development of digestive system tumors through the PI3K pathway by summarizing recent research.

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.

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.

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

AIM: To examine the correlation of phosphatidylinositol 3-kinase (PIK3) CB expression with preoperative radiotherapy response in patients with stage II/III rectal adenocarcinoma.

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.

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 （MI-I-） assay. Phase-contrast and electron microscopy were used to observe the morphological changes. Cell cycle and mitochondrial transmembrane potential （A^Pm） 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 pmol/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 SGC7901 cells 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.

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.

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.

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

AIM： To investigate whether Src, JAK2 and phosphatidylinositol 3-kinase （PI3K） pathways are involved in the proliferation of human colonic tumour cells induced by glycine-extended gastrin （G-gly）, the precursor of the mature amidated gastrin and to elucidate the molecular interaction between these three kinases in response to this peptide. METHODS： Using the human colonic tumour cell line HCT116 as a model, we first measured the activation of PI3K, p60-Src and JAK2 in response to G-gly by in vitro kinase assays. Then we investigated the involvement of these kinases in G-gly-induced cell proliferation by MTT test. RESULTS： G-gly stimulation induced p60-Src, JAK2 and PI3K activation in HCT116. The different pathways were involved in proliferation of human colon cancer cells induced by G-gly. Furthermore, we found that both Src and JAK2 were necessary to PI3K regulation by this peptide. However, we did not find any cross-talk between the two tyrosine kinases. CONCLUSION： Our results suggest that the p60-Src/ PI3K and JAK2/PI3K pathways act independently to mediate G-gly proliferative effect on human colonic tumour cells.

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.

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/AKT signaling and neuroprotection in ischemic stroke:molecular mechanisms and therapeutic perspectives

It has been reported that the PI3K/AKT signaling pathway plays a key role in the pathogenesis of ischemic stroke.As a result,the development of drugs targeting the PI3K/AKT signaling pathway has attracted increasing attention from researchers.This article reviews the pathological mechanisms and advancements in research related to the signaling pathways in ischemic stroke,with a focus on the PI3K/AKT signaling pathway.The key findings include the following:(1)The complex pathological mechanisms of ischemic stroke can be categorized into five major types:excitatory amino acid toxicity,Ca^(2+)overload,inflammatory response,oxidative stress,and apoptosis.(2)The PI3K/AKT-mediated signaling pathway is closely associated with the occurrence and progression of ischemic stroke,which primarily involves the NF-κB,NRF2,BCL-2,mTOR,and endothelial NOS signaling pathways.(3)Natural products,including flavonoids,quinones,alkaloids,phenylpropanoids,phenols,terpenoids,and iridoids,show great potential as candidate substances for the development of innovative anti-stroke medications.(4)Recently,novel therapeutic techniques,such as electroacupuncture and mesenchymal stem cell therapy,have demonstrated the potential to improve stroke outcomes by activating the PI3K/AKT signaling pathway,providing new possibilities for the treatment and rehabilitation of patients with ischemic stroke.Future investigations should focus on the direct regulatory mechanisms of drugs targeting the PI3K/AKT signaling pathway and their clinical translation to develop innovative treatment strategies for ischemic stroke.

Impacts of PI3K/protein kinase B pathway activation in reactive astrocytes: from detrimental effects to protective functions

Astrocytes are the most abundant type of glial cell in the central nervous system.Upon injury and inflammation,astrocytes become reactive and undergo morphological and functional changes.Depending on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,respectively.However,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and injuries.Transcriptomic analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their reactivity.Astrocytes actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune response.The phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo results.In astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory responses.Here,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their activation.We highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3K/AKT/connexin 43,and Notch/PI3K/AKT pathways.While targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial outcomes.This dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function modulation.The review emphasizes the importance of employing astrocyte-exclusive models to understand their functions accurately and these models are essential for clarifying astrocyte behavior.The findings should then be validated using in vivo models to ensure real-life relevance.The review also highlights the significance of PI3K/AKT pathway modulation in preventing central nervous system damage,although further studies are required to fully comprehend its role due to varying factors such as different cell types,astrocyte responses to inflammation,and disease contexts.Specific strategies are clearly necessary to address these variables effectively.

基于PI3K/AKT信号通路探讨DJ-1蛋白对抑郁症大鼠海马中神经递质的影响

目的探讨DJ-1蛋白对抑郁症大鼠神经递质的影响。方法TUNEL(terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling)试剂盒检测细胞凋亡率。酶联免疫吸附法测定血清中肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)和白细胞介素-6(interleukin-6,IL-6)的含量,海马区中5-羟色胺(5-hydroxytryptamine,5-HT)、5-羟吲哚乙酸(5-hydroxyindoleacetic acid,5-HIAA)、多巴胺(dopamine,DA)的水平;蛋白质印迹检测海马区DJ-1、磷脂酰肌醇3激酶(phosphatidylinositol 3 kinase,PI3K)、蛋白激酶B(protein kinase B,AKT)、p-PI3K、p-AKT、Bcl-2和Bcl-2相关X蛋白(Bcl-2 associated X protein,Bax)的表达。结果过表达DJ-1后能明显降低中细胞凋亡率和血清中TNF-α和IL-6的含量,上调海马区5-HT、5-HIAA、DA的水平,上调p-PI3K、p-AKT和Bcl-2的表达,抑制Bax的表达,但PI3K抑制剂LY294002可部分解除过表达DJ-1对神经元细胞的保护作用。结论过表达DJ-1后能明显抑制抑郁症大鼠炎症性应激,降低细胞的凋亡率,上调中5-HT、5-HIAA和DA的含量,这可能与激活PI3K/AKT信号有关。

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.

Class I phosphatidylinositol 3-kinase inhibitors for cancer therapy

The phosphatidylinositol 3-kinase(PI3K) pathway is frequently activated in human cancers.Class I PI3 Ks are lipid kinases that phosphorylate phosphatidylinositol 4,5-bisphosphate(PIP2) at the 3-OH of the inositol ring to generate phosphatidylinositol 3,4,5-trisphosphate(PIP3), which in turn activates Akt and the downstream effectors like mammalian target of rapamycin(m TOR) to play key roles in carcinogenesis. Therefore, PI3 K has become an important anticancer drug target, and currently there is very high interest in the pharmaceutical development of PI3 K inhibitors. Idelalisib has been approved in USA and Europe as the first-in-class PI3 K inhibitor for cancer therapy. Dozens of other PI3 K inhibitors including BKM120 and ZSTK474 are being evaluated in clinical trials. Multifaceted studies on these PI3 K inhibitors are being performed, such as single and combinational efficacy, resistance, biomarkers,etc. This review provides an introduction to PI3 K and summarizes key advances in the development of PI3 K inhibitors.

Jiaotai Pill(交泰丸) Enhances Insulin Signaling through Phosphatidylinositol 3-Kinase Pathway in Skeletal Muscle of Diabetic Rats

objective： To investigate the effect of Jiaotai Pill （交泰丸, JTP） at different constitutional proportions on insulin signaling through phosphatidylinositol 3-kinase （PI3K） pathway in the skeletal muscle of diabetic rats. Methods： The rat model of type 2 diabetes mellitus （T2DM） was established by intravenous injection of a small dose of streptozotoein plus high fat diet feeding. JTP at the same dosage of cinnamon and the increasing dosage of Coptis chinensis was administered to diabetic rats for nine weeks respectively. Plasma glucose and insulin levels were assayed. The expressions of proteins were determined by Western blot method. Results： All the three formulations of JTP decreased plasma glucose and fasting insulin levels as well as increased the protein expressions of insulin receptor β （InsR β） subunit, insulin receptor substrate-1 （IRS-1）, PI3K p85 subunit and glucose transporter 4 （GLUT4） in skeletal muscle. Meanwhile, JTP increased the tyrosine phosphorylation of InsRβ subunit and IRS-1, and reduced the serine phosphorylation of IRS-1 in skeletal muscle. Interestingly, the effect of JTP on improving insulin sensitivity was not dose-dependent. In contrast, JTP containing the least amount of Coptis chinensis exhibited the best effect. Conclusion： JTP at different constitutional proportions attenuates the development of diabetes in a rat model of T2DM. The mechanism might be associated with enhancing insulin signaling through PI3K pathway in the skeletal muscle.

Intracellular and Extracellular Phosphatidylinositol 3-Phosphate Produced by Phytophthora Species Is Important for Infection

RxLR effectors produced by Phytophthora pathogens have been proposed to bind to phosphatidylinositol 3-phosphate （Ptdlns（3）P） to mediate their translocation into host cells and/or to increase their stability in planta. Since the levels of Ptdlns（3）P in plants are low, we examined whether Phytophthora species may produce Ptdlns（3）P to pro- mote infection. We observed that Ptdlns（3）P-specific GFP biosensors could bind to P. parasitica and P. sojae hyphae dur- ing infection of Nicotiana benthamiana leaves transiently secreting the biosensors, suggesting that the hyphae exposed Ptdlns（3）P on their plasma membrane and/or secreted Ptdlns（3）R Silencing of the phosphatidylinositol 3-kinases （PI3K） genes, treatment with LY294002, or expression of Ptdlns（3）pobinding proteins by P. sojae reduced the virulence of the pathogen on soybean, indicating that pathogen-synthesized Ptdlns（3）P was required for full virulence. Secretion of Ptdlns（3）P-binding proteins or of a PI3P-5-kinase by N. benthamiana leaves significantly increased the level of resist- ance to infection by P. parasitica and P. capsici. Together, our results support the hypothesis that Phytophthora species produce external Ptdlns（3）P to aid in infection, such as to promote entry of RxLR effectors into host cells. Our results derived from P. sojae RxLR effector Avrlb confirm that both the N-terminus and the C-terminus of this effector can bind Ptdlns（3）P.

Electroacupuncture Pretreatment at Neiguan (PC 6) attenuates autophagy in rats with myocardial ischemia reperfusion through the phosphatidylinositol 3-kinase-Akt-mammalian target of rapamycin pathway

OBJECTIVE: To investigate the protective efficacy of electroacupuncture(EA) pretreatment at Neiguan(PC6) on myocardial ischemia-reperfusion(I/R) in rats.METHODS: Fifty rats were randomly divided into five groups(n = 10): sham operation group, model group(underwent in vivo myocardial I/R), EA pretreatment group [EA at Neiguan(PC 6) 1 week before I/R], wortmannin group(1 week before I/R, the PI3K inhibitor, wortmannin, was injected), EA pretreatment + wortmannin group(both pretreatments were performed simultaneously). After establishing the I/R model, 2,3,5-triphenyltetrazolium chloride(TTC) staining was used to analyze the weight and area of the myocardial infarction tissue.The biosignal and pressure test system was used to determine the left ventricular systolic mean pressure(LVSP), left ventricular end-diastolic pressure(LVEDP), fractional shortening(FS), and ejection fraction(EF). Ultraviolet spectrophotometry was used to determine the expression of creatine kinase(CK)-MB, inducible nitric oxide synthase(i NOS), and total antioxidant capacity(T-AOC) in the serum. The expression of autophagy-related protein 13(ATG13), mammalian target of rapamycin(m TOR), and phosphatidylinositol 3-kinase(PI3K) in cardiac muscle cells was determined by immunofluorescence. Hematoxylin and eosin staining was used to observe autophagy-related pathological changes in rat cardiomyocytes, and ultrastructural changes of cardiomyocytes were examined by transmission electron microscopy.RESULTS: In this study, the infarction size and tissue weight of the EA pretreatment group were decreased compared with the model group(P <0.0001). Furthermore, compared with the model group, the LVEDP values of the EA pretreatment group were significantly reduced(P = 0.0091), and the LVSP, FS, and EF values were slightly increased (P = 0.0007, 0.0020, 0.0031). EA pretreatment also significantly decreased the expression of CK-MB and i NOS, while it increased the expression of T-AOC in the serum of rats with I/R injury(P <0.0001). Furthermore, EA pretreatment slightly widened the myocardial fiber space, reduced necrosis and myocardial cell swelling and maintained the nucleus and mitochondria structure intact.CONCLUSION: EA pretreatment promoted autophagy flux and alleviated myocardial I/R injury through the PI3K-Akt-m TOR pathway.

Effects of Panax Quinquefolium Saponin on Phosphatidylinositol 3-Kinase/Serine Threonine Kinase Pathway of Neonatal Rat Myocardial Cells Subjected to Hypoxia

Objective： To explore the effects of Panax Quinquefolium Saponin （PQS） on phosphatidylinositol 3-kinase/serine threonine kinase （P13/Akt） pathway of neonatal rat myocardial cells subjected to hypoxia. Methods： Neonatal rat myocardial cells were cultured in vitro. After the myocardial cell injury was induced by hypoxia, the cells were randomized into 5 groups： the normal group, the model group, the positive control group （Ciclosporin A, 2 p, mol/L）, the low-dose PQS group （PQSL, 25mg/L）, and the high-dose PQS group （PQSH, 50 mg/L）. Morphology and behavior of myocardial cells were observed under an inverted microscope. Apoptosis rate and lactate dehydrogenase （LDH） leakage rate of myocardial cells were determined by colorimetry. Mitochondrial transmembrane potential was assessed using a fluorexon laser. Phospho-glycogen synthase kinase （GSK）-3β and phospho-Akt as well as cytochrome C were determined by Western blot. Results： LDH leakage in the Ciclosporin A group, PQSH group and PQSL group reduced progressively compared with the model group （P〈0.05）. Akt and GSK-3β was strongly phosphorylated after treatment with Ciclosporin A and PQS compared with the model group （P〈0.05, P〈0.01）. Compared with the model group （16.41 ± 1.74; 35.28 ± 6.30）, both the integrated optical density of mitochondrial permeability transition pore （MPTP） and the mitochondrial transmembrane potential significantly increased in the PQSH group （42.74± 2.12; 71.36 ± 6.54） and the PQSL group （39.58± 1.49; 66.99± 5.45; P〈0.05, P〈0.01）. However, the protein of cytochrome C outside the mitochonddon decreased in the PQSH group （273.66 ± 14.61） and the PQSL group （259.62 ± 17.31） compared with the model group （502.41 ± 17.76; P〈0.05）. Conclusion： Through activation of the P13K/Akt pathway and inhibition of the MPTP, PQS might protect the heart against ischemia injury and apoptosis of myocardial cells.