Oleanolic acid inhibits colon cancer cell stemness and reverses chemoresistance by suppressing JAK2/STAT3 signaling pathway

Background:Oleanolic acid(OA),a pentacyclic triterpenoid exhibiting specific anti-cancer properties and highly effective antioxidant activity,was isolated from traditional Chinese medicinal herbs.Conversely,the OA that impacts colon cancer(CC)cells and its underlying mechanisms remain poorly understood.Methods:The cytotoxic effect of OA alone or OA-5-Fluorouracil(5-FU)combination on normal and CC cells was analyzed by methyl thiazolyl diphenyl-tetrazolium bromide(MTT).Then,the impact of OA on CC cell lines(LoVo and HT-29)proliferation and stemness were measured using colon formation and tumorsphere formation assays.Octamer-binding transcription factor 4(Oct4),Prominin-1(CD133),Nanog,and transcription factor SOX-2(SOX2)are cell stemness-related indicators whose expression was assessed usingfluorescence qPCR assay,Western blotting,and immunohistochemistry.The effect of OA on the proliferative potency of CC cells was evaluated using an in vivo model.Results:The stem-like characteristics and clone production of colon cancer cells were markedly reduced by OA alone or in combination with OA-5-FU.Moreover,OA increases the susceptibility of CC cells to 5-FU by blocking the cell stemness-related markers(CD133,Nanog,SOX2,and Oct4)expression levels both in vitro and in vivo,as well as by inactivating the activator of transcription 3(STAT3 signaling)and Janus kinase 2/signal transducer(JAK2).Conclusion:Thesefindings imply that oleanolic acid,both in vitro and in vivo,suppresses the JAK2/STAT3 pathway,which in turn reverses chemoresistance and decreases colon cancer cell stemness.Therefore,by reducing the recommended amount of 5-FU,this strategy may improve chemotherapeutic effectiveness and minimize undesired side effects.

Effects of plumbagin on migration and invasion of human hepatoma cell line via JAK2/STAT3 signaling pathway

Objective:To study the effect of plumbagin(PL)on the migration and invasion of human hepatocellular carcinoma(HCC)cells and its possible mechanism.Methods:The cell counting kit(CCK-8)was used to detect the effects of different concentrations of plumbagin on the proliferation of human hepatocellular carcinoma Huh-7 and LM3 cells.The effect of plumbagin on the migration ability of Huh-7 and LM3 cells was detected by scratch test and Transwell migration test,and the effect of on the invasion ability of Huh-7 and LM3 cells was detected by Transwell invasion test.Western Blot was used to detect the expression of E-cadherin,N-cadherin,matrix metalloproteinase-2 and related proteins in JAK2/STAT3 signaling pathway in Huh-7 and LM3 cells.Results:Plumbagin could inhibit the proliferation of Huh-7 and LM3 cells in a time-and concentration-dependent manner.Plumbagin inhibited the migration and invasion of Huh-7 and LM3 cells in a concentration dependent manner,and it can down-regulate the expression of N-cadherin and MMP-2 protein,up-regulate the expression of E-cadherin protein,and inhibit the activation of JAK2/STAT3 signaling pathway.Conclusion:Plumbagin can inhibit the migration and invasion of human hepatocellular carcinoma Huh-7 and LM3 cells,and the molecular mechanism of this process may be related to the inhibition of JAK2/STAT3 signaling pathway activation.

To explore the mechanism of Dahuang Lingxian Formula in relieving inflammatory response of bile duct cells based on IL-6/JAK/STAT3 signaling pathway

Objective:To explore the mechanism of action of Dahuang Lingxian Formula in alleviating the inflammatory response of bile duct cells in LPS-induced intrahepatic bile duct inflammation model rats based on IL-6/JAK/STAT3 signaling pathway.Methods:Fifty SD rats were randomly divided into five groups,blank group,model group,choling tablets(0.5 g/kg),and low and high concentration groups(2.4 g/kg and 4.8 g/kg)of Dahuang Lingxian Formula,ten rats in each group.Except for the blank group,the rats in each group were injected with 1.25 mg/kg LPS at the common bile duct at one time to construct an animal model of intrahepatic bile duct infection.After gavage on day 8,liver tissues were taken from rats at the hepatic hilum,and the histopathological changes of the hepatic hilum and biliary tree were observed by HE staining.The expression levels of serum glutamic alanine transaminase(ALT),glutamic oxalacetic transaminase(AST),malondialdehyde(MDA)and superoxide dismutase(SOD)were measured by biochemical method.The expression levels of interleukin 6(IL-6),Janus protein tyrosine kinase 2(JAK2),signal transducer and activator of transcription 3(STAT3)in rat serum were measured by enzyme-linked immunosorbent assay(ELISA).Protein immunoblotting(WB)and real-time fluorescence quantitative PCR(RT-qPCR)were used to detect the expression levels of IL-6,JAK2,STAT3 protein and mRNA in biliary tree tissues.Results:①Compared with the blank group,the structures such as interlobular bile ducts in the hepatic sinusoids and portal duct area of the model rats were destroyed,and inflammatory cells infiltrated around them.The expression of ALT,AST,MDA,IL-6,JAK2 and STAT3 in the serum increased significantly,the expression level of SOD decreased,and the expression levels of IL-6,JAK2 and STAT3 proteins and mRNA increased.②Compared with the model group,the degree of liver pathological damage in rats in the Chiling Ning tablet group and the low and high concentration groups of Dahuang Lingxian Formula were improved,which could significantly reduce the expression levels of ALT,AST,MDA,IL-6,JAK2,STAT3 and up-regulate SOD in serum,and down-regulate the expression of IL-6,JAK2,STAT3 protein and mRNA,with the best effect in the high concentration group of Dahuang Lingxian Formula.③Compared with the choling tablet group,the rats in the low and high concentration groups of Dahuang Lingxian Formula tended to normalize the degree of liver pathological damage,without obvious inflammatory cell infiltration,and the expression levels of ALT,AST,MDA,IL-6,JAK2,STAT3 and the expression levels of IL-6,JAK2,STAT3 protein and mRNA in serum were reduced,and the expression levels of SOD were increased,with the best effect of Dahuang Lingxian Formula The treatment effect was best in the high concentration group.Conclusion:The mechanism may be related to the down-regulation of IL-6/JAK/STAT3 signaling pathway activation,and the best therapeutic effect was achieved by the high concentration group of Dahuang Lingxian Formula.

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.

3-epi-bufotalin suppresses the proliferation in colorectal cancer cells through the inhibition of the JAK1/STAT3 signaling pathway

Traditional Chinese medicine(TCM)has been increasingly employed in the last decades in China for both preventing and treating a variety of cancers.3-epi-bufotalin is an active ingredient of TCM“Chanpi”with anti-tumor potential.However,the effect and mechanism of 3-epi-bufotalin on colorectal cancers were not well disclosed.The present study demonstrated that 3-epi-bufotalin could reduce viability,trigger apoptosis,and block the cell cycle at the G2/M stage in colorectal cancer cell lines HT29,RKO,and COLO205 in vitro.Moreover,3-epi-bufotalin inhibited the JAK1/STAT3 signaling pathway.These results indicated the anti-proliferation ability of 3-epi-bufotalin in colorectal cancer cells.

GPR160 regulates the self-renewal and pluripotency of mouse embryonic stem cells via JAK1/STAT3 signaling pathway

G-protein-coupled receptors(GPCRs)are the largest family of transmembrane receptors and regulate various physiological and pathological processes.Despite extensive studies,the roles of GPCRs in mouse embryonic stem cells(mESCs)remain poorly understood.Here,we show that GPR160,a class A member of GPCRs,is dramatically downregulated concurrent with mESC differentiation into embryoid bodies in vitro.Knockdown of Gpr160 leads to downregulation of the expression of pluripotency-associated transcription factors and upregulation of the expression of lineage markers,accompanying with the ar-rest of the mESC cell-cycle in the GO/G1 phase.RNA-seq analysis shows that GPR160 participates in the JAK/STAT signaling pathway crucial formaintaining ESC stemness,and the knockdown of Gpr160 results in the downregulation of STAT3 phosphorylation level,which in turn is partially rescued by colivelin,a STAT3 activator.Consistent with these observations,GPR160 physically interacts with JAK1,and co-operates with leukemia inhibitory factor receptor(LIFR)and gp130 to activate the STAT3 pathway.In summary,our results suggest that GPR160 regulates mESC self-renewal and pluripotency by interacting with the JAK1-LIFR-gp130 complex to mediate the JAK1/STAT3 signaling pathway.

Hepatocellular carcinoma-derived exosomal miRNA-761 regulates the tumor microenvironment by targeting the SOCS2/JAK2/STAT3 pathway

BACKGROUND:Exosomes and exosomal microRNAs have been implicated in tumor occurrence and metastasis.Our previous study showed that microRNA-761(miR-761)is overexpressed in hepatocellular carcinoma(HCC)tissues and that its inhibition affects mitochondrial function and inhibits HCC metastasis.The mechanism by which exosomal miR-761 modulates the tumor microenvironment has not been elucidated.METHODS:Exosomal miR-761 was detected in six cell lines.Cell counting kit-8(CCK-8)and transwell migration assays were performed to determine the function of exosomal miR-761 in HCC cells.The luciferase reporter assay was used to analyze miR-761 target genes in normal fi broblasts(NFs).The inhibitors AZD1480 and C188-9 were employed to determine the role of the Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)signaling pathway in the transformation of cancer-associated fi broblasts(CAFs).RESULTS:In this study,we characterized the mechanism by which miR-761 reprogrammed the tumor microenvironment.We found that HCC-derived exosomal miR-761 was taken up by NFs.Moreover,HCC exosomes aff ected the tumor microenvironment by activating NFs via suppressor of cytokine signaling 2(SOCS2)and the JAK2/STAT3 signaling pathway.CONCLUSIONS:These results demonstrated that exosomal miR-761 modulated the tumor microenvironment via SOCS2/JAK2/STAT3 pathway-dependent activation of CAFs.Our fi ndings may inspire new strategies for HCC prevention and therapy.

HBP1 inhibits chicken preadipocyte differentiation by activating the STAT3 signaling via directly enhancing JAK2 expression

Obesity presents a serious threat to human health and broiler performance.The expansion of adipose tissue is mainly regulated by the differentiation of preadipocytes.The differentiation of preadipocytes is a complex biological process regulated by a variety of transcription factors and signaling pathways.Previous studies have shown that the transcription factor HMG-box protein 1(HBP1)can regulate the differentiation of mouse 3T3-L1 preadipocytes by activating the Wnt/β-catenin signaling pathway.However,it is unclear whether HBP1 involved in chicken preadipocyte differentiation and which signaling pathways it regulates.The aim of the current study was to explore the biological function and molecular regulatory mechanism of HBP1 in the differentiation of chicken preadipocytes.The expression patterns of chicken HBP1 in abdominal adipose tissue and during preadipocyte differentiation were analyzed by RT-qPCR and Western blot.The preadipocyte stably overexpressing HBP1 or knockout HBP1 and their control cell line were used to analyze the effect of HBP1 on preadipocyte differentiation by oil red O staining,RT-qPCR and Western blot.Cignal 45-Pathway Reporter Array was used to screen the signal pathways that HBP1 regulates in the differentiation of chicken preadipocytes.Chemical inhibitor and siRNA for signal transducer and activator of transcription 3(STAT3)were used to analyze the effect of STAT3 on preadipocyte differentiation.The preadipocyte stably overexpressing HBP1 was transfected by the siRNA of STAT3 or treated with a chemical inhibitor of STAT3 for the rescue experiment.The results of gene expression analysis showed that the expression of HBP1 was related to abdominal fat deposition and preadipocyte differentiation in chickens.The results of function gain and loss experiments indicated that overexpression/knockout of HBP1 in chicken preadipocytes could inhibit/promote(P<0.05)lipid droplet deposition and the expression of adipogenesis-related genes.Mechanismlly,HBP1 activates(P<0.05)the signal transducer and activator of transcription 3(STAT3)signaling pathway by targeting janus kinase 2(JAK2)transcription.The results of functional rescue experiments indicated that STAT3 signaling mediated the regulation of HBP1 on chicken preadipocyte differentiation.In conclusion,HBP1 inhibits chicken preadipocyte differentiation by activating the STAT3 signaling pathway via directly enhancing JAK2 expression.Our findings provided new insights for further analysis of the molecular genetic basis of chicken adipose tissue growth and development.

STAT3-specific nanocarrier for shRNA/drug dual delivery and tumor synergistic therapy

Non-small cell lung cancer(NSCLC)is a major disease with high incidence,low survival rate and prone to develop drug resistance to chemotherapy.The mechanism of secondary drug resistance in NSCLC chemotherapy is very complex,and studies have shown that the abnormal activation of STAT3(Signal Transducer and Activator of Transcription 3)plays an important role in it.In this study,the pGPU6/GFP/Neo STAT3-shRNA recombinant plasmid was constructed with STAT3 as the precise target.By modifying hydrophilic and hydrophobic blocks onto chitosan,a multifunctional vitamin E succinate-chitosan-polyethylene glycol monomethyl ether histidine(VES-CTS-mPEG-His)micelles were synthesized.The micelles could encapsulate hydrophobic drug doxorubicin through self-assembly,and load the recombinant pGPU6/GFP/Neo STAT3-shRNA(pDNA)through positive and negative charges to form dual-loaded nanoparticles DOX/VCPH/pDNA.The co-delivery and synergistic effect of DOX and pDNA could up-regulate the expression of PTEN(Phosphatase and Tensin Homolog),down-regulate the expression of CD31,and induce apoptosis of tumor cells.The results of precision targeted therapy showed that DOX/VCPH/pDNA could significantly down-regulate the expression level of STAT3 protein,further enhancing the efficacy of chemotherapy.Through this study,precision personalized treatment of NSCLC could be effectively achieved,reversing its resistance to chemotherapy drugs,and providing new strategies for the treatment of drug-resistant NSCLC.

Sphingosine kinase 1 promotes growth of glioblastoma by increasing inflammation mediated by the NF-κB/IL-6/STAT3 and JNK/PTX3 pathways

Glioblastoma(GBM)is the most challenging malignant tumor of the central nervous system because of its high morbidity,mortality,and recurrence rate.Currently,mechanisms of GBM are still unclear and there is no effective drug for GBM in the clinic.Therefore,it is urgent to identify new drug targets and corresponding drugs for GBM.In this study,in silico analyses and experimental data show that sphingosine kinase 1(SPHK1)is up-regulated in GBM patients,and is strongly correlated with poor prognosis and reduced overall survival.Overexpression of SPHK1 promoted the proliferation,invasion,metastasis,and clonogenicity of GBM cells,while silencing SPHK1 had the opposite effect.SPHK1 promoted inflammation through the NF-κB/IL-6/STAT3 signaling pathway and led to the phosphorylation of JNK,activating the JNK-JUN and JNK-ATF3 pathways and promoting inflammation and proliferation of GBM cells by transcriptional activation of PTX3.SPHK1 interacted with PTX3 and formed a positive feedback loop to reciprocally increase expression,promote inflammation and GBM growth.Inhibition of SPHK1 by the inhibitor,PF543,also decreased tumorigenesis in the U87-MG and U251-MG SPHK1 orthotopic mouse models.In summary,we have characterized the role and molecular mechanisms by which SPHK1 promotes GBM,which may provide opportunities for SPHK1-targeted therapy.

Sustained release of magnesium and zinc ions synergistically accelerates wound healing

Skin wounds are a major medical challenge that threaten human health.Functional hydrogel dressings demonstrate great potential to promote wound healing.In this study,magnesium(Mg)and zinc(Zn)are introduced into methacrylate gelatin(GelMA)hydrogel via low-temperature magnetic stirring and photocuring,and their effects on skin wounds and the underlying mechanisms are investigated.Degradation testing confirmed that the GelMA/Mg/Zn hydrogel released magnesium ions(Mg^(2+))and zinc ions(Zn^(2+))in a sustained manner.The Mg^(2+) and Zn^(2+)not only enhanced the migration of human skin fibroblasts(HSFs)and human immortalized keratinocytes(HaCats),but also promoted the transformation of HSFs into myofibroblasts and accelerated the production and remodeling of extracellular matrix.Moreover,the GelMA/Mg/Zn hydrogel enhanced the healing of full-thickness skin defects in rats via accelerated collagen deposition,angiogenesis and skin wound re-epithelialization.We also identified the mechanisms through which GelMA/Mg/Zn hydrogel promoted wound healing:the Mg^(2+) promoted Zn^(2+)entry into HSFs and increased the concentration of Zn^(2+)in HSFs,which effectively induced HSFs to differentiate into myofibroblasts by activating the STAT3 signaling pathway.The synergistic effect of Mg^(2+) and Zn^(2+)promoted wound healing.In conclusion,our study provides a promising strategy for skin wounds regeneration.

The spirocyclopiperazinium salt compound LXM-15 alleviates chronic inflammatory and neuropathic pain in mice and rats

In the present study,we aimed to evaluate the effect of the spirocyclopiperazinium salt compound LXM-15 on chronic inflammatory pain and chronic neuropathic pain induced by complete Freund’s adjuvant(CFA)or chronic constriction injury(CCI)in mice and rats.The results showed that administration with LXM-15 significantly reduced paw edema and ankle swelling and increased the mechanical withdrawal threshold and paw withdrawal latency after CFA injection in mice.LXM-15 significantly alleviated the mechanical allodynia and thermal hyperalgesia in CCI rats.The effect was abolished by pretreatment with hexamethonium(a peripheral nAChR antagonist)or methyllycaconitine citrate(anα7 nAChR antagonist).Furthermore,LXM-15 significantly inhibited the phosphorylation of JAK2 and STAT3,and suppressed the expressions of TNF-αand c-fos in dorsal root ganglia of CCI rats.Collectively,we reported that LXM-15 relieved chronic inflammatory pain in CFA mice and chronic neuropathic pain in CCI rats.The underlying mechanism might be related to the activation of peripheralα7 nicotinic receptor,further inhibiting JAK2/STAT3 signaling pathway,and eventually suppressing the expressions of TNF-αand c-fos.