Dickkopf-related protein 1/cytoskeleton-associated protein 4 signaling activation by Helicobacter pylori-induced activator protein-1 promotes gastric tumorigenesis via the PI3K/AKT/mTOR pathway

BACKGROUND Gastric cancer(GC)is a common malignant tumor with high incidence and mortality rates globally,especially in East Asian countries.Helicobacter pylori(H.pylori)infection is a significant and independent risk factor for GC.However,its underlying mechanism of action is not fully understood.Dickkopf-related protein(DKK)1 is a Wnt signaling antagonist,and cytoskeleton-associated protein(CKAP)4 is a newly identified DKK1 receptor.Recent studies found that the binding of DKK1 to CAKP4 mediated the procancer signaling of DKK1 independent of Wnt signaling.We hypothesize that H.pylori-induced activation of DKK1/CKAP4 signaling contributes to the initiation and progression of GC.AIM To investigate the interaction of H.pylori infection,DKK1 and CAKP4 in GC,as well as the underlying molecular mechanisms.METHODS RNA sequencing was used to identify differentially expressed genes(DEGs)between H.pylori-infected and uninfected primary GC cells.Gain-and loss-offunction experiments were performed to verify the H.pylori-induced upregulation of activator protein-1(AP-1)in GC cells.A dual-luciferase reporter assay and co-immunoprecipitation were used to determine the binding of AP-1 to the DKK1 promoter and DKK1 to CKAP4.Western blotting and immunohistochemistry detected the expression of DKK1,CKAP4,and phosphatidylinositol 3-kinase(PI3K)pathway-related proteins in GC cells and tissues.Functional experiments and tumorigenicity in nude mice detected malignant behavior of GC cells in vitro and in vivo.RESULTS We identified 32 DEGs between primary GC cells with and without H.pylori infection,including JUN,fos-like antigen-1(FOSL1),and DKK1,and confirmed that the three proteins and CKAP4 were highly expressed in H.pylori-infected GC cells,H.pylori-infected gerbil gastric tissues,and human GC tissues.JUN and FOSL1 form AP-1 to transcriptionally activate DKK1 expression by binding to the DKK1 promoter.Activated DKK1 bound to CKAP4,but not the most common Wnt coreceptor low-density lipoprotein receptor-related protein 5/6,to promote GC cell growth,colony formation,migration,invasion,and xenograft tumor growth in nude mice.All these effects were driven by activation of the PI3K/AKT/mammalian target of rapamycin(mTOR)pathway.Targeting the PI3K signaling pathway by LY294002 inhibited DKK1-mediated CKAP4/PI3K signaling activity and the malignant behavior of GC cells.CONCLUSION H.pylori induces JUN and FOSL1 expression to form AP-1,which transcriptionally activates DKK1.Binding of DKK1 to KAKP4 contributes to gastric tumorigenesis via the PI3K/AKT/mTOR pathway.

Pachymic acid exerts antitumor activities by modulating the Wnt/β-catenin signaling pathway via targeting PTP1B

Objective:To determine the inhibitory effects of pachymic acid on lung adenocarcinoma(LUAD)cells and elucidate its underlying mechanism.Methods:CCK-8,wound healing,Transwell,Western blot,tube formation,and immunofluorescence assays were carried out to measure the effects of various concentrations of pachymic acid on LUAD cell proliferation,metastasis,angiogenesis as well as autophagy.Subsequently,molecular docking technology was used to detect the potential targeted binding association between pachymic acid and protein tyrosine phosphatase 1B(PTP1B).Moreover,PTP1B was overexpressed in A549 cells to detect the specific mechanisms of pachymic acid.Results:Pachymic acid suppressed LUAD cell viability,metastasis as well as angiogenesis while inducing cell autophagy.It also targeted PTP1B and lowered PTP1B expression.However,PTP1B overexpression reversed the effects of pachymic acid on metastasis,angiogenesis,and autophagy as well as the expression of Wnt3a andβ-catenin in LUAD cells.Conclusions:Pachymic acid inhibits metastasis and angiogenesis,and promotes autophagy in LUAD cells by modulating the Wnt/β-catenin signaling pathway via targeting PTP1B.

ZNF554 Inhibits Endometrial Cancer Progression via Regulating RBM5 and Inactivating WNT/β-Catenin Signaling Pathway

Objective:Uterine corpus endometrial carcinoma(UCEC),a kind of gynecologic malignancy,poses a significant risk to women’s health.The precise mechanism underlying the development of UCEC remains elusive.Zinc finger protein 554(ZNF554),a member of the Krüppel-associated box domain zinc finger protein superfamily,was reported to be dysregulated in various illnesses,including malignant tumors.This study aimed to examine the involvement of ZNF554 in the development of UCEC.Methods:The expression of ZNF554 in UCEC tissues and cell lines were examined by qRT-PCR and Western blot assay.Cells with stably overexpressed or knocked-down ZNF554 were established through lentivirus infection.CCK-8,wound healing,and Transwell invasion assays were employed to assess cell proliferation,migration,and invasion.Propidium iodide(PI)staining combined with fluorescence-activated cell sorting(FACS)flow cytometer was utilized to detect cell cycle distribution.qRT-PCR and Western blotting were conducted to examine relative mRNA and protein levels.Chromatin immunoprecipitation assay and luciferase reporter assay were used to explore the regulatory role of ZNF554 in RNA binding motif 5(RBM5).Results:The expression of ZNF554 was found to be reduced in both UCEC samples and cell lines.Decreased expression of ZNF554 was associated with higher tumor stage,decreased overall survival,and reduced disease-free survival in UCEC.ZNF554 overexpression suppressed cell proliferation,migration,and invasion,while also inducing cell cycle arrest.In contrast,a decrease in ZNF554 expression resulted in the opposite effect.Mechanistically,ZNF554 transcriptionally regulated RBM5,leading to the deactivation of the Wingless(WNT)/β-catenin signaling pathway.Moreover,the findings from rescue studies demonstrated that the inhibition of RBM5 negated the impact of ZNF554 overexpression onβ-catenin and p-glycogen synthase kinase-3β(p-GSK-3β).Similarly,the deliberate activation of RBM5 reduced the increase inβ-catenin and p-GSK-3βcaused by the suppression of ZNF554.In vitro experiments showed that ZNF554 overexpression-induced decreases in cell proliferation and migration were counteracted by RBM5 knockdown.Additionally,when RBM5 was overexpressed,it hindered the improvements in cell proliferation and migration caused by reducing the ZNF554 levels.Conclusion:ZNF554 functions as a tumor suppressor in UCEC.Furthermore,ZNF554 regulates UCEC progression through the RBM5/WNT/β-catenin signaling pathway.ZNF554 shows a promise as both a prognostic biomarker and a therapeutic target for UCEC.

Up-regulated Wnt1-inducible signaling pathway protein 1 correlates with poor prognosis and drug resistance by reducing DNA repair in gastric cancer

BACKGROUND Wnt1-inducible signaling pathway protein 1(WISP1)is upregulated in several types of human cancer,and has been implicated in cancer progression.However,its clinical implications in gastric cancer(GC)remain unclear.AIM To explore the expression pattern and clinical significance of WISP1 in GC.METHODS Public data portals,including Oncomine,The Cancer Genome Atlas database,Coexpedia,and Kaplan-Meier plotter,were analyzed for the expression and clinical significance of WISP1 mRNA levels in GC.One hundred and fifty patients who underwent surgery for GC between February 2010 and October 2012 at the Affiliated Hospital of Jiangnan University were selected for validation study.WISP1 levels were measured at both the mRNA and protein levels by RTqPCR,Western blot analysis,and immunohistochemistry(IHC).In addition,the in situ expression of WISP1 in the GC tissues was determined by IHC,and the patients were accordingly classified into high-and low-expression groups.The correlation of WISP1 expression status with patient prognosis was then determined by univariate and multivariate Cox regression analyses.WISP1 was knocked down by RNA interference.The 50%inhibitory concentration of oxaliplatin was detected by CellTiter-Blue assay.RESULTS WISP1 levels at both the mRNA and protein levels were remarkably upregulated in GC tissues compared to normal tissues.Moreover,IHC revealed that WISP1 expression was associated with T stage and chemotherapy outcome,but not with lymph node metastasis,age,gender,histological grade,or histological type.GC patients with high WISP1 expression showed a poor overall survival.Multivariate survival analysis indicated that WISP1 was an important prognostic factor for GC patients.Mechanistically,knock-down of WISP1 expression enhanced sensitivity to oxaliplatin by reducing DNA repair and enhancing DNA damage.CONCLUSION Significantly upregulated WISP1 expression is associated with cancer progression,chemotherapy outcome,and prognosis in GC.Mechanistically,knock-down of WISP1 expression enhances oxaliplatin sensitivity by reducing DNA repair and enhancing DNA damage.WISP1 may be a potential therapeutic target for GC treatment or a potential biomarker for diagnosis and prognosis.

Calcitriol attenuates liver fibrosis through hepatitis C virus nonstructural protein 3-transactivated protein 1-mediated TGF β1/Smad3 and NF-κB signaling pathways

BACKGROUND Hepatic fibrosis is a serious condition,and the development of hepatic fibrosis can lead to a series of complications.However,the pathogenesis of hepatic fibrosis remains unclear,and effective therapy options are still lacking.Our group identified hepatitis C virus nonstructural protein 3-transactivated protein 1(NS3TP1) by suppressive subtractive hybridization and bioinformatics analysis,but its role in diseases including hepatic fibrosis remains undefined.Therefore,additional studies on the function of NS3TP1 in hepatic fibrosis are urgently needed to provide new targets for treatment.AIM To elucidate the mechanism of NS3TP1 in hepatic fibrosis and the regulatory effects of calcitriol on NS3TP1.METHODS Twenty-four male C57BL/6 mice were randomized and separated into three groups,comprising the normal,fibrosis,and calcitriol treatment groups,and liver fibrosis was modeled by carbon tetrachloride(CCl4).To evaluate the level of hepatic fibrosis in every group,serological and pathological examinations of the liver were conducted.TGF-β1 was administered to boost the in vitro cultivation of LX-2 cells.NS3TP1,α-smooth muscle actin(α-SMA),collagen I,and collagen Ⅲ in every group were examined using a Western blot and real-time quantitative polymerase chain reaction.The activity of the transforming growth factor beta 1(TGFβ1)/Smad3 and NF-κB signaling pathways in each group of cells transfected with pcDNA-NS3TP1 or siRNA-NS3TP1 was detected.The statistical analysis of the data was performed using the Student’s t test.RESULTS NS3TP1 promoted the activation,proliferation,and differentiation of hepatic stellate cells(HSCs)and enhanced hepatic fibrosis via the TGFβ1/Smad3 and NF-κB signaling pathways,as evidenced by the presence of α-SMA,collagen I,collagen Ⅲ,p-smad3,and p-p65 in LX-2 cells,which were upregulated after NS3TP1 overexpression and downregulated after NS3TP1 interference.The proliferation of HSCs was lowered after NS3TP1 interference and elevated after NS3TP1 overexpression,as shown by the luciferase assay.NS3TP1 inhibited the apoptosis of HSCs.Moreover,both Smad3 and p65 could bind to NS3TP1,and p65 increased the promoter activity of NS3TP1,while NS3TP1 increased the promoter activity of TGFβ1 receptor I,as indicated by coimmunoprecipitation and luciferase assay results.Both in vivo and in vitro,treatment with calcitriol dramatically reduced the expression of NS3TP1.Calcitriol therapy-controlled HSCs activation,proliferation,and differentiation and substantially suppressed CCl4-induced hepatic fibrosis in mice.Furthermore,calcitriol modulated the activities of the above signaling pathways via downregulation of NS3TP1.CONCLUSION Our results suggest that calcitriol may be employed as an adjuvant therapy for hepatic fibrosis and that NS3TP1 is a unique,prospective therapeutic target in hepatic fibrosis.

Elevated retinol binding protein 4 levels are associated with atherosclerosis in diabetic rats via JAK2/STAT3 signaling pathway

BACKGROUND Atherosclerosis is a major cause of mortality worldwide and is driven by multiple risk factors,including diabetes,which results in an increased atherosclerotic burden,but the precise mechanisms for the occurrence and development of diabetic atheroscerosis have not been fully elucidated.AIM To summarize the potential role of retinol binding protein 4(RBP4) in the pathogenesis of diabetic atheroscerosis,particularly in relation to the RBP4-Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)signaling pathway.METHODS Male Wistar rats were randomly divided into three groups,including a control group(NC group),diabetic rat group(DM group),and diabetic atherosclerotic rat group(DA group).The contents of total cholesterol(TC), high-density lipoprotein cholesterol(HDL-c), triglycerides(TG), low-density lipoprotein cholesterol(LDLc), fasting insulin(FINS),fasting plasma glucose,and hemoglobin A1 c(HbA1 c)were measured.Moreover,the adipose and serum levels of RBP4,along with the expression levels of JAK2, phosphorylated JAK2(p-JAK2), STAT3,phosphorylated STAT3(p-STAT3), B-cell lymphoma-2(Bcl-2), and Cyclin D1 in aortic tissues were also measured.Besides,homeostasis model assessment of insulin resistance(HOMA-IR) and atherogenic indexes(AI) were calculated.RESULTS Compared with the NC and DM groups,the levels LDL-c,TG,TC,FINS,HOMAIR,RBP4,and AI were upregulated,whereas that of HDL-c was downregulated in the DA group(P <0.05);the mRNA levels of JAK2,STAT3,Cyclin D1,and Bcl-2 in the DA group were significantly increased compared with the NC group and the DM group;P-JAK2,p-JAK2/JAK2 ratio,p-STAT3,p-STAT3/STAT3 ratio,Cyclin D1,and Bcl-2 at protein levels were significantly upregulated in the DA group compared with the NC group and DM group.In addition,as shown by Pearson analysis,serum RBP4 had a positive correlation with TG,TC,LDL-c,FINS,HbA1 C,p-JAK2,p-STAT3,Bcl-2,Cyclin D1,AI,and HOMA-IR but a negative correlation with HDL-c.In addition,multivariable logistic regression analysis showed that serum RBP4,p-JAK2,p-STAT3,and LDL-c were predictors of the presence of diabetic atherosclerosis.CONCLUSION RBP4 could be involved in the initiation or progression of diabetic atherosclerosis by regulating the JAK2/STAT3 signaling pathway.

Geniposide, the component of the Chinese herbal formula Tongluojiunao, protects amyloid-β peptide(1–42)-mediated death of hippocampal neurons via the non-classical estrogen signaling pathway

Tongluojiunao （TLJN） is an herbal medicine consisting of two main components, geniposide and ginsenoside Rg1. TLJN has been shown to protect primary cultured hippocampal neurons. How-ever, its mechanism of action remains unclear. In the present study, primary cultured hippocampal neurons treated with Aβ1-42 （10 μmol/L） signiifcantly increased the release of lactate dehydroge-nase, which was markedly reduced by TLJN （2 μL/mL）, speciifcally by the component geniposide （26 μmol/L）, but not ginsenoside Rg1 （2.5 μmol/L）. hTe estrogen receptor inhibitor, ICI182780 （1 μmol/L）, did not block TLJN-or geniposide-mediated decrease of lactate dehydrogenase under Aβ1-42-exposed conditions. However, the phosphatidyl inositol 3-kinase or mitogen-activated protein kinase pathway inhibitor, LY294002 （50 μmol/L） or U0126 （10 μmol/L）, respectively blo cked the decrease of lactate dehydrogenase mediated by TLJN or geniposide. hTerefore, these results suggest that the non-classical estrogen pathway （i.e., phosphatidyl inositol 3-kinase or mitogen-activated protein kinase） is involved in the neuroprotective effect of TLJN, speciifcally its component, geniposide, against Aβ1-42-mediated cell death in primary cultured hippocampal neurons.

IL-1RⅠ/MyD88-TIR mimic AS-1 inhibits the activation of MyD88-dependent signaling pathway induced by IL-1β in vitro

Objective： To test whether IL-1 RI/My088-TIR mimic AS-1 can work as a new compound that targeted at blocking MyD88- dependent signaling pathway, we investigated the physical structure and biological function of AS-1. Methods：The crystallographic structure of AS-1 was examined by 1^H nuclear magnetic resonance. The toxicity of AS-1 was measured with Methyl thiazolyl tetrazolium （MTT） assay. The effect of AS-1 on phosphorylation state of p38 MAPK and IRAK-1 was observed with Western blot. Results：The crystallographic details of AS-1 demonstrated that it was a tri-peptide sequence[（F/Y）-（V/L/I）-（P/G）] of the IL-1R I -TIR domain BBloop. No toxicity of AS-1 was shown to HEK 293A cells. The phosphorylation of p38 MAPK, induced by IL-1β significantly increased from those in the control group. AS-1 significantly reduced the phosphorylation of p38 MAPK induced by IL-1β. IL-1β increased the phosphorylation of IRAK-1 significantly, which was prevented by AS-1. Conclusion：AS-1 is a competitive mimic between IL-1R I-TIR and MyD88-TIR domain, which most likely interferes with MyD88-dependent signaling pathway.

CYP24A1 Involvement in Inflammatory Factor Regulation Occurs via the Wnt Signaling Pathway

Objective While the upregulation of cytochrome P450 family 24 subfamily A member 1(CYP24A1)gene expression has been reported in colon cancer,its role in tumorigenesis remains largely unknown.In this study,we aimed to investigate the involvement of CYP24A1 in Wnt pathway regulation via the nuclear factor kappa B(NF-κB)pathway.Methods The human colon cancer cell lines HCT-116 and Caco-2 were subjected to stimulation with interleukin-6(IL-6)as well as tumor necrosis factor alpha(TNF-α),with subsequent treatment using the NF-κB pathway-specific inhibitor ammonium pyrrolidinedithiocarbamate(PDTC).Furthermore,CYP24A1 expression was subjected to knockdown via the use of small interfering RNA(siRNA).Subsequently,NF-κB pathway activation was determined by an electrophoretic mobility shift assay,and the transcriptional activity ofβ-catenin was determined by a dual-luciferase reporter assay.A mouse ulcerative colitis(UC)-associated carcinogenesis model was established,wherein TNF-αand the NF-κB pathway were blocked by anti-TNF-αmonoclonal antibody and NF-κB antisense oligonucleotides,respectively.Then the tumor size and protein level of CYP24A1 were determined.Results IL-6 and TNF-αupregulated CYP24A1 expression and activated the NF-κB pathway in colon cancer cells.PDTC significantly inhibited this increase in CYP24A1 expression.Additionally,knockdown of CYP24A1 expression by siRNA could partially antagonize Wnt pathway activation.Upregulated CYP24A1 expression was observed in the colonic epithelial cells of UC-associated carcinoma mouse models.Anti-TNF-αmonoclonal antibody and NF-κB antisense oligonucleotides decreased the tumor size and suppressed CYP24A1 expression.Conclusion Taken together,this study suggests that inflammatory factors may increase CYP24A1 expression via NF-κB pathway activation,which in turn stimulates Wnt signaling.

Mutations in components of the Wnt signaling pathway in gastric cancer

AIM: To explore the contribution of AXIN1, AXIN2 and beta-catenin, components of Wnt signaling pathway, to the carcinogenesis of gastric cancer (GC), we examined AXIN1, AXIN2 exon7 and CTNNB1 (encoding beta- catenin) exon3 mutations in 70 GCs. METHODS: The presence of mutations was identified by polymerase chain reaction (PCR)-based denaturing high-performance liquid chromatography and direct DNA sequencing. Beta-catenin expression was detected by immunohistochemical analysis. RESULTS: Among the 70 GCs, 5 (7.1%) had mutations in one or two of these three components. A frameshift mutation (1 bp deletion) in exon7 of AXIN2 was found in one case. Four cases, including the case with a mutation in AXIN2, had frameshift mutations and missense mutations in AXIN1. Five single nucleotide polymorphisms (SNPs), 334 C>T, 874 C>T, 1396 G>A, 1690 C>T and 1942 T>G, were identified in AXIN1. A frameshift mutation (27 bp deletion) spanning exon3 of CTNNB1 was observed in one case. All four cases with mutations in AXIN1 and AXIN2 showed nuclear beta- catenin expression. CONCLUSION: These data indicate that the mutationsin AXIN1 and AXIN2 may contribute to gastric carcino- genesis.

Barley Protein LFBEP-C1 from Lactiplantibacillus plantarum dy-1 Fermented Barley Extracts by Inhibiting Lipid Accumulation in a Caenorhabditis elegans Model

Objective This study aimed to investigate the lipid-lowering activity of LFBEP-C1 in high glucose-fed Caenorhabditis elegans(C.elegans).Methods In this study,the fermented barley protein LFBEP-C1 was prepared and tested for its potential anti-obesity effects on C.elegans.The worms were fed Escherichia coli OP50(E.coli OP50),glucose,and different concentrations of LFBEP-C1.Body size,lifespan,movement,triglyceride content,and gene expression were analyzed.The results were analyzed using ANOVA and Tukey's multiple comparison test.Results Compared with the model group,the head-swing frequency of C.elegans in the group of LFBEP-C1 at 20μg/mL increased by 33.88%,and the body-bending frequency increased by 27.09%.This indicated that LFBEP-C1 improved the locomotive ability of C.elegans.The average lifespan of C.elegans reached 13.55 days,and the body length and width of the C.elegans decreased after LFBEP-C1 intake.Additionally,LFBEP-C1 reduced the content of lipid accumulation and triglyceride levels.The expression levels of sbp-1,daf-2,and mdt-15 significantly decreased,while those of daf-16,tph-1,mod-1,and ser-4 significantly increased after LFBEP-C1 intake.Changes in these genes explain the signaling pathways that regulate lipid metabolism.Conclusion LFBEP-C1 significantly reduced lipid deposition in C.elegans fed a high-glucose diet and alleviated the adverse effects of a high-glucose diet on the development,lifespan,and exercise behavior of C.elegans.In addition,LFBEP-C1 regulated lipid metabolism mainly by mediating the expression of genes in the sterol regulatory element-binding protein,insulin,and 5-hydroxytryptamine signaling pathways.

Involvement of the Wnt signaling pathway and cell apoptosis in the rat hippocampus following cerebral ischemia/reperfusion injury

We investigated the role of the Wnt signaling pathway in cerebral ischemia/reperfusion injury by examining β-catenin and glycogen synthase kinase-3β protein expression in the rat hippocampal CA1 region following acute cerebral ischemia/reperfusion. Our results demonstrate that cell apoptosis increases in the CA1 region following ischemia/reperfusion. In addition, β-catenin and glycogen synthase kinase-3β protein expression gradually increases, peaking at 48 hours following reperfusion. Dickkopf-1 administration, after cerebral ischemia/reperfusion injury, results in decreased cell apoptosis, and β-catenin and glycogen synthase kinase-3β expression, in the CA1 region. This suggests that β-catenin and glycogen synthase kinase-3β, both components of the Wnt signaling pathway, participate in cell apoptosis following cerebral ischemia/reperfusion injury.

Angelica sinensis polysaccharides ameliorate 5-flourouracil-induced bone marrow stromal cell proliferation inhibition via regulating Wnt/β-catenin signaling

Chemotherapy may cause cellular oxidative stress to bone marrow.Oxidative damage of bone marrow hematopoietic microenvironment is closely related to chronic myelosuppression after chemotherapeutic treatment.Angelica sinensis polysaccharides(ASP)are major effective ingredients of traditional Chinese medicine Angelica with multi-target anti-oxidative stress features.In the current study,we investigated the protective roles and mechanisms of ASP on chemotherapy-induced bone marrow stromal cell(BMSC)damage.The human bone marrow stromal cell line HS-5 cells were divided into control group,5-FU group,5-FU+ASP group,and 5-FU+LiCl group to investigate the mechanism of ASP to alleviate 5-FU-induced BMSC proliferation inhibition.The results showed that 5-FU inhibits the growth of HS-5 cells in a time and dose-dependent manner;however,ASP partially counteracted the 5-FU-induced decrease in cell viability,whereas Wnt signaling inhibitor Dkk1 antagonized the effect of ASP on HS-5 cells.ASP reversed the decrease in total cytoplasmicβ-catenin,p-GSK-3β,and CyclinD1 following 5-FU treatment and modulated nuclear expression ofβ-catenin,Lef-1,and C-myc proteins.Furthermore,ASP also enhanced the antioxidant capacity of cells and reduced 5-FU-induced oxidative stress,attenuated FoxO1 expression,thus weakened its downstream apoptosis-related proteins and G0/G1 checkpoint-associated p27^(Kip1) expression to alleviate 5-FU-induced apoptosis and to promote cell cycle progression.All the results above suggest that the protective role of ASP in 5-FU-treated BMSCs proliferation for the chemotherapy may be related to its activating Wnt/β-catenin signaling and keeping homeostasis betweenβ-catenin and FoxO1 under oxidative stress.The study provides a potential therapeutic strategy for alleviating chemotherapeutic damage on BMSCs.

Insulin-like growth factor binding protein related protein 1 knockdown attenuates hepatic ?brosis via the regulation of MMPs/TIMPs in mice

Background: Previous research suggested that insulin-like growth factor binding protein related protein 1(IGFBPrP1), as a novel mediator, contributes to hepatic fibrogenesis. Matrix metalloproteinases(MMP) and tissue inhibitors of metalloproteinases(TIMP) play an essential role in hepatic fibrogenesis by regulating homeostasis and remodeling of the extracellular matrix(ECM). However, the interaction between IGFBPrP1 and MMP/TIMP is not clear. The present study was to knockdown IGFBPrP1 to investigate the correlation between IGFBPrP1 and MMP/TIMP in hepatic fibrosis. Methods: Hepatic fibrosis was induced by thioacetamide(TAA) in mice. Knockdown of IGFBPrP1 expression by ultrasound-targeted microbubble destruction-mediated CMB-shRNA-IGFBPrP1 delivery, or inhibition of the Hedgehog(Hh) pathway by cyclopamine treatment, was performed in TAA-induced liver fibrosis mice. Hepatic fibrosis was determined by hematoxylin and eosin and Sirius red staining. Hepatic expression of IGFBPrP1, α-smooth muscle actin( α-SMA), transforming growth factor β 1(TGF β1), collagen I, MMPs/TIMPs, Sonic Hedgehog(Shh), and glioblastoma family transcription factors(Gli1) were investigated by immunohistochemical staining and Western blotting analysis. Results: We found that hepatic expression of IGFBPrP1, TGF β1, α-SMA, and collagen I were increased longitudinally in mice with TAA-induced hepatic fibrosis, concomitant with MMP2/TIMP2 and MMP9/TIMP1 imbalance and Hh pathway activation. Knockdown of IGFBPrP1 expression, or inhibition of the Hh pathway, reduced the hepatic expression of IGFBPrP1, TGF β1, α-SMA, and collagen I and re-established MMP2/TIMP2 and MMP9/TIMP1 balance. Conclusions: Our findings suggest that IGFBPrP1 knockdown attenuates liver fibrosis by re-establishing MMP2/TIMP2 and MMP9/TIMP1 balance, concomitant with the inhibition of hepatic stellate cell activation, down-regulation of TGF β1 expression, and degradation of the ECM. Furthermore, the Hh pathway mediates IGFBPrP1 knockdown-induced attenuation of hepatic fibrosis through the regulation of MMPs/TIMPs balance.

Roles of low?density lipoproteinreceptor?related protein 1 in tumors

Low-density lipoprotein receptor-related protein 1(LRP1,also known as CD91),a multifunctional endocytic and cell signaling receptor,is widely expressed on the surface of multiple cell types such as hepatocytes,fibroblasts,neurons,astrocytes,macrophages,smooth muscle cells,and malignant cells.Emerging in vitro and in vivo evidence demonstrates that LRP1 is critically involved in many processes that drive tumorigenesis and tumor progression.For example,LRP1 not only promotes tumor cell migration and invasion by regulating matrix metalloproteinase(MMP)-2and MMP-9 expression and functions but also inhibits cell apoptosis by regulating the insulin receptor,the serine/threonine protein kinase signaling pathway,and the expression of Caspase-3.LRPI-mediated phosphorylation of the extracellular signal-regulated kinase pathway and c-jun N-terminal kinase are also involved in tumor cell proliferation and invasion.In addition,LRP1 has been shown to be down-regulated by microRNA-205 and methylation of LRP1CpG islands.Furthermore,a novel fusion gene,LRP1-SNRNP25,promotes osteosarcoma cell invasion and migration.Only by understanding the mechanisms of these effects can we develop novel diagnostic and therapeutic strategies for cancers mediated by LRP1.

Mitogen-activated protein kinase phosphatase 1 protects PC12 cells from amyloid beta-induced neurotoxicity

The mitogen-activated protein kinase（MAPK） signaling pathway plays an important role in the regulation of cell growth, proliferation, differentiation, transformation and death. Mitogen-activated protein kinase phosphatase 1（MKP1） has an inhibitory effect on the p38 MAPK and JNK pathways, but it is unknown whether it plays a role in Aβ-induced oxidative stress and neuronal inflammation. In this study, PC12 cells were infected with MKP1 sh RNA, MKP1 lentivirus or control lentivirus for 12 hours, and then treated with 0.1, 1, 10 or 100 μM amyloid beta 42（Aβ42）. The cell survival rate was measured using the cell counting kit-8 assay. MKP1, tumor necrosis factor-alpha（TNF-α） and interleukin-1β（IL-1β） m RNA expression levels were analyzed using quantitative real time-polymerase chain reaction. MKP1 and phospho-c-Jun N-terminal kinase（JNK） expression levels were assessed using western blot assay. Reactive oxygen species（ROS） levels were detected using 2′,7′-dichlorofluorescein diacetate. Mitochondrial membrane potential was measured using flow cytometry. Superoxide dismutase activity and malondialdehyde levels were evaluated using the colorimetric method. Lactate dehydrogenase activity was measured using a microplate reader. Caspase-3 expression levels were assessed by enzyme-linked immunosorbent assay. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase d UTP nick end labeling method. MKP1 overexpression inhibited Aβ-induced JNK phosphorylation and the increase in ROS levels. It also suppressed the Aβ-induced increase in TNF-α and IL-1β levels as well as apoptosis in PC12 cells. In contrast, MKP1 knockdown by RNA interference aggravated Aβ-induced oxidative stress, inflammation and cell damage in PC12 cells. Furthermore, the JNK-specific inhibitor SP600125 abolished this effect of MKP1 knockdown on Aβ-induced neurotoxicity. Collectively, these results show that MKP1 mitigates Aβ-induced apoptosis, oxidative stress and neuroinflammation by inhibiting the JNK signaling pathway, thereby playing a neuroprotective role.

Correlation between receptor-interacting protein 140 expression and directed differentiation of human embryonic stem cells into neural stem cells

Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural differentiation remains unclear.We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells.Moreover,RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation,and positively correlated with the neural stem cell marker Nestin during later stages.Thus,ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.

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.

脱氧核苷酸转移酶末端相互作用蛋白1通过ERK信号通路促进鼻咽癌细胞侵袭及转移机制研究

目的探讨脱氧核苷酸转移酶末端相互作用蛋白1(deoxynucleotidyltransferase,terminal,interacting protein 1,DNTTIP1)通过细胞外调节蛋白激酶(extracellular regulated protein kinases,ERK)信号通路促进鼻咽癌侵袭及转移机制。方法选用人鼻咽癌细胞系(HK1)作为研究对象,分为观察组与对照组,观察组中细胞转入含有DNTTIP1基因的载体,对照组转入空白载体。采用Trizol法提取细胞中的总RNA,细胞划痕及Transwell小室实验检测细胞的迁移及侵袭能力,Western blot法检测ERK信号通路相关蛋白的表达情况。结果DNTTIP1在观察组HK1细胞中的表达水平明显高于对照组(2.75±0.43 vs.1.00±0.01),差异有统计学意义(t=9.966,P<0.05)。观察组中HK1细胞迁移及侵袭明显增强,差异有统计学意义(P<0.05)。与对照组比较,观察组HK1细胞中的p-ERKl/2蛋白表达水平明显上升(0.64±0.13 vs.1.26±0.15),差异有统计学意义(t=7.651,P<0.05)。ERK+3'-UTR+DNTTIP1组中ERK相对表达量明显高于ERK+3'-UTR组(1.71±0.21 vs.1.00±0.01),差异有统计学意义(t=8.272,P<0.05)。结论DNTTIP1通过ERK信号通路促进鼻咽癌侵袭及转移,该通路对鼻咽癌相关疾病的治疗具有潜在的医学价值。

Apoptosis of mesenchymal stem cells is regulated by Rspo1 via the Wnt/β-catenin signaling pathway

Objective: The aim of this study was to investigate the effect and possible mechanism of action of roof plate-specific spondin1 (Rspo1) in the apoptosis of rat bone marrow mesenchymal stem cells (BMSCs). Methods: Osteogenic and adipogenic differentiation of BMSCs was identified by Alizarin Red and Oil Red O staining, respectively. BMSC surface markers (cluster of differentiation 29 [CD29], CD90, and CD45) were detected using flow cytometry. BMSCs were transfected with an adenoviral vector encoding Rspo1 (BMSCs-Rspo1 group). The expression levels of Rspo1 gene and Rspo1 protein in the BMSCs-Rspo1 group and the two control groups (untransfected BMSCs group and BMSCs-green fluorescent protein [GFP] group) were analyzed and compared by quantitative polymerase chain reaction and Western blot. The occurrence of apoptosis in the three groups was detected by flow cytometry and acridine orange-ethidium bromide (AO-EB) double dyeing. The activity of the Wnt/β-catenin signaling pathway was evaluated by measuring the expression levels of the key proteins of the pathway (β-catenin, c-Jun N-terminal kinase [JNK], and phospho-JNK). Results: Osteogenic and adipogenic differentiation was confirmed in cultured BMSCs by the positive expression of CD29 and CD90 and the negative expression of CD45. Significantly increased expression levels of Rspo1 protein in the BMSCs-Rspo1 group compared to those in the BMSCs (0.60 ± 0.05 vs. 0.13 ± 0.02;t=95.007, P=0.001) and BMSCs-GFP groups (0.60 ± 0.05 vs. 0.10 ± 0.02;t=104.842, P=0.001) were observed. The apoptotic rate was significantly lower in the BMSCs-Rspo1 group compared with those in the BMSCs group ([24.06 ± 2.37]% vs.[40.87 ± 2.82]%;t =49.872, P =0.002) and the BMSCs-GFP group ([24.06 ± 2.37]% vs.[42.34 ± 0.26]%;t =62.358, P =0.001). In addition, compared to the BMSCs group, the protein expression levels of β-catenin (2.67 ± 0.19 vs. 1.14 ± 0.14;t =-9.217, P =0.000) and JNK (1.87 ± 0.17 vs. 0.61 ± 0.07;t =-22.289, P =0.000) were increased in the BMSCs-Rspo1 group. Compared to the BMSCs-GFP group, the protein expression levels of β-catenin (2.67 ± 0.19 vs. 1.44 ± 0.14;t =-5.692, P =0.000) and JNK (1.87 ± 0.17 vs. 0.53 ± 0.06;t =-10.589, P =0.000) were also upregulated in the BMSCs-Rspo1 group. Moreover, the protein expression levels of phospho-JNK were increased in the BMSCs-Rspo1 group compared to those in the BMSCs group (1.89 ± 0.10 vs. 0.63 ± 0.09;t =-8.975, P =0.001) and the BMSCs-GFP group (1.89 ± 0.10 vs. 0.69 ± 0.08;t =-9.483, P =0.001). Conclusion: The Wnt/β-catenin pathway could play a vital role in the Rspo1-mediated inhibition of apoptosis in BMSCs.