Effects of chimeric intron on the epithelial-mesenchymal transformation of non-small cell lung cancer PC-9

Objective:To investigate the effects of Intron on the EMT capability of non-small cell lung cancer cell line PC-9.Methods:Firstly,using the psiCHECK-2 plasmid as a basic framework to construct the recombinant plasmid of psiCHECK-2-Intron dual-luciferase reporter gene;secondly,the psiCHECK-2-Intron and psiCHECK-2 were transfected into PC-9 cells respectively.The migration and invasion abilities of PC-9 cells were analyzed by Matrigel assay.The expression changes of EMT related hallmarks,including N-cadherin,β-catenin and snail,were detected by qRT-PCR and Western Blotting.Results:Compared with the control group,the migration and invasion abilities of PC-9 cells in Intron group significantly decreased(p<0.001).The expression of N-cadherin,β-catenin and snail also down-regulated(p<0.001).Conclusion:The introns could inhibit the EMT of PC-9 cells.

Role of reactive oxygen species in epithelial-mesenchymal transition and apoptosis of human lens epithelial cells

AIM:To investigate the role of reactive oxygen species(ROS)in epithelial–mesenchymal transition(EMT)and apoptosis of human lens epithelial cells(HLECs).METHODS:Flow cytometry was used to assess ROS production after transforming growth factorβ2(TGF-β2)induction.Apoptosis of HLECs after H_(2)O_(2) and TGF-β2 interference with or without ROS scavenger N-acetylcysteine(NAC)were assessed by flow cytometry.The corresponding protein expression levels of the EMT markerα-smooth muscle actin(α-SMA),the extracellular matrix(ECM),marker fibronectin(Fn),and apoptosis-associated proteins were detected by using Western blotting in the presence of an ROS scavenger(NAC).Wound-healing and Transwell assays were used to assess the migration capability of HLECs.RESULTS:TGF-β2 stimulates ROS production within 8h in HLECs.Additionally,TGF-β2 induced HLECs cell apoptosis,EMT/ECM synthesis protein markers expression,and pro-apoptotic proteins production;nonetheless,NAC treatment prevented these responses.Similarly,TGF-β2 promoted HLECs cell migration,whereas NAC inhibited cell migration.We further determined that although ROS initiated apoptosis,it only induced the accumulation of the EMT markerα-SMA protein,but not COL-1 or Fn.CONCLUSION:ROS contribute to TGF-β2-induced EMT/ECM synthesis and cell apoptosis of HLECs;however,ROS alone are not sufficient for EMT/ECM synthesis.

Hsa_circRNA_102610 upregulation in Crohn’s disease promotes transforming growth factor-β1-induced epithelial-mesenchymal transition via sponging of hsa-miR-130a-3p

BACKGROUND The incidence of inflammatory bowel disease,a chronic intestinal inflammatory disorder that includes Crohn’s disease(CD)and ulcerative colitis,is rising.Circular RNAs are considered valuable diagnostic biomarkers for CD.Current evidence supports the views that epithelial-mesenchymal transition(EMT)plays an important role in CD pathogenesis,and that hsa-miR-130a-3p can inhibit transforming growth factor-β1(TGF-β1)-induced EMT.Our previous study revealed that hsa_circRNA_102610 was upregulated in CD patients.Moreover,we predicted an interaction between hsa_circRNA_102610 and hsa-miR-130a-3p.Thus,we hypothesized that hsa_circRNA_102610 may play roles in the proliferation and EMT of intestinal epithelial cells by sponging hsa-miR-130a-3p to participate in the pathogenesis of CD.AIM To explore the mechanism of hsa_circRNA_102610 in the pathogenesis of CD.METHODS The relative expression levels of hsa_circRNA_102610 and hsa-miR-130a-3p in patients were detected by quantitative reverse transcription-polymerase chain reaction.The proliferation of human intestinal epithelial cells(HIECs)and normal-derived colon mucosa cell line 460(NCM460)cells was detected by cell counting kit-8,5-ethynyl-2’-deoxyuridine staining and cell cycle assays following overexpression or downregulation of hsa_circRNA_102610.Cell proliferation assays were performed as described above in a rescue experiment with hsa-miR-130a-3p mimics.The interaction of hsa_circRNA_102610 and hsa-miR-130a-3p was verified by fluorescence in situ hybridization and dual luciferase reporter assays.The relative expression levels of CyclinD1,mothers against decapentaplegic homolog 4(SMAD4),E-cadherin,N-cadherin and Vimentin were detected by western blotting following hsa_circRNA_102610 overexpression,TGF-β1-induced EMT or hsa-miR-130a-3p mimic transfection(in rescue experiments).RESULTS Upregulation of hsa_circRNA_102610 was determined to be positively correlated with elevated fecal calprotectin levels in CD(r=0.359,P=0.007)by Pearson correlation analysis.Hsa_circRNA_102610 promoted the proliferation of HIECs and NCM460 cells,while hsa-miR-130a-3p reversed the cell proliferationpromoting effects of hsa_circRNA_102610.Fluorescence in situ hybridization and dual luciferase reporter assays showed that hsa_circRNA_102610 directly bound hsa-miR-130a-3p in NCM460 and 293T cells.An inverse correlation between downregulation of hsa-miR-130a-3p and upregulation of hsa_circRNA_102610 in CD patients was observed(r=-0.290,P=0.024)by Pearson correlation analysis.Moreover,overexpression of hsa_circRNA_102610 promoted SMAD4 and CyclinD1 protein expression validated by western-blotting.Furthermore,overexpression of hsa_circRNA_102610 promoted TGF-β1 induced EMT in HIECs and NCM460 cells via targeting of hsa-miR-130a-3p,with increased expression of Vimentin and N-cadherin and decreased expression of E-cadherin.CONCLUSION Hsa_circRNA_102610 upregulation in CD patients could promote the proliferation and EMT of intestinal epithelial cells via sponging of hsa-miR-130a-3p.

EDIL3 depletion suppress epithelial-mesenchymal transition of lens epithelial cells via transforming growth factor β pathway

AIM： To study the effect of discoidin I-like domaincontaining protein 3（EDIL3） depletion on the proliferation and epithelial-mesenchymal transition（EMT） in human lens epithelial cells（LECs）. METHODS： RNA interference was used to inhibit the expression of EDIL3 in human LECs in vitro. The morphology of cells was observed using an inverted microscope. Cell proliferation was assessed using Ed U kit. Cell migration was investigated using Transwell chamber and EMT of LECs was assessed using confocal microscope and Western blotting. The transforming growth factor β（TGFβ） pathway was investigated using Western blotting. RESULTS： The data showed that silencing EDIL3 expression changed LECs morphology and suppressed LECs proliferation（P〈0.05） and migration（P〈0.01）. Furthermore, the result of Western blotting showed that EDIL3 depletion reduced the expression of α-smooth muscle actin（α-SMA）（P〈0.001） and vimentin（P〈0.01）, while increased the expression of E-cadherin（P〈0.001）. EDIL3 depletion could suppress the phosphorylation of Smad2（P〈0.01） and Smad3（P〈0.01） and the activation of exracellular signal regulated kinase（ERK）（P〈0.05）. CONCLUSION： The findings indicate that EDIL3 might participate in the proliferation and EMT in LECs via TGFβ pathway and may be a potential therapeutic target for the treatment of posterior capsule opacification.

Inhibition of Ubiquitin-specific Protease 4 Attenuates Epithelial-Mesenchymal Transition of Renal Tubular Epithelial Cells via Transforming Growth Factor Beta Receptor Type Ⅰ

Objective Ubiquitin-specific protease 4(USP4)facilitates the development of transforming growth factor-beta 1(TGF-β1)-induced epithelial-mesenchymal transition(EMT)in various cancer cells.Moreover,EMT of renal tubular epithelial cells(RTECs)is required for the progression of renal interstitial fibrosis.However,the role of USP4 in EMT of RTECs remains unknown.The present study aimed to explore the effect of USP4 on the EMT of RTECs as well as the involved mechanism.Methods In established unilateral ureteral obstruction(UUO)rats and NRK-52E cells,immunohistochemistry and Western blot assays were performed.Results USP4 expression was increased significantly with obstruction time.In NRK-52E cells stimulated by TGF-β1,USP4 expression was increased in a time-dependent manner.In addition,USP4 silencing with specific siRNA indicated that USP4 protein was suppressed effectively.Meanwhile,USP4 siRNA treatment restored E-cadherin and weakened alpha smooth muscle actin(α-SMA)expression,indicating that USP4 may promote EMT.After treatment with USP4 siRNA and TGF-β1 for 24 h,the expression of TGF-β1 receptor type I(TβRI)was decreased.Conclusion USP4 promotes the EMT of RTECs through upregulating TβRI,thereby facilitating renal interstitial fibrosis.These findings may provide a potential target of USP4 in the treatment of renal fibrosis.

Mechanisms of fibrogenesis in liver cirrhosis:The molecular aspects of epithelial-mesenchymal transition

Liver injuries are repaired by fibrosis and regeneration.The cause of fibrosis and diminished regeneration,especially in liver cirrhosis,is still unknown.Epithelialmesenchymal transition(EMT) has been found to be associated with liver fibrosis.The possibility that EMT could contribute to hepatic fibrogenesis reinforced the concept that activated hepatic stellate cells are not the only key players in the hepatic fibrogenic process and that other cell types,either hepatic or bone marrow-derived cells could contribute to this process.Following an initial enthusiasm for the discovery of this novel pathway in fibrogenesis,more recent research has started to cast serious doubts upon the real relevance of this phenomenon in human fibrogenetic disorders.The debate on the authenticity of EMT or on its contribution to the fibrogenic process has become very animated.The overall result is a general confusion on the meaning and on the definition of several key aspects.The aim of this article is to describe how EMT participates to hepatic fibrosis and discuss the evidence of supporting this possibility in order to reach reasonable and useful conclusions.

Saponin Ⅰ from Shuitianqi(Rhizoma Schizocapasae Plantagineae) inhibits metastasis by negatively regulating the transforming growth factor-β1/Smad7 network and epithelial-mesenchymal transition in the intrahepatic metastasis Bagg's Albino/c mouse model

OBJECTIVE:To examine the influence of SaponinⅠfrom Shuitianqi(Rhizoma Schizocapasae Plantagineae)(SSPHⅠ)on hepatocellular carcinoma(HCC)metastasis,and to elucidate the underlying mechanism.METHODS:The intrahepatic metastasis Bagg's Albino/c(BALB/c)mouse model was established with human hepatocellular carcinomas(HepG2)cells,then treated with normal saline(once per day),cisplatin(2 mg/kg,once every 2 d),and SSPHⅠ(25,50,and 75 mg/kg,once per day).Then,we assessed alterations in the hepatic pathology and target protein expressions in the intrahepatic metastasis BALB/c mouse model using a series of molecular biology techniques.RESULTS:Based on our analysis,SSPHⅠsignificantly alleviated hepatocyte necrosis and tumor cells infiltration.Moreover,SSPHⅠsuppressed extracellular matrix(ECM)degradation and angiogenesis via a decrease in matrix etalloproteinase-2(MMP-2),MMP-9,CD31,CD34,and vascular endothelial growth factor(VEGF)levels.Furthermore,SSPHⅠrepressed invasion and metastasis by suppressing the transforming growth factor-β1(TGF-β1)/Smad7 axis and epithelial-mesenchymal transition(EMT),as evidenced by the scarce TGF-β1,Ncadherin,and Vimentin expressions,and elevated Smad7 and E-cadherin expressions.CONCLUSION:The SSPHⅠ-mediated negative regulation of the TGF-β1/Smad7 axis and EMT are critical for the inhibition of HCC invasion and metastasis.

The role of mechanical stretch and TGF-β2 in epithelial-mesenchymal transition of retinal pigment epithelial cells

AIM: To explore the effects and mechanisms of mechanical stress and transforming growth factor-beta2(TGF-β2) on epithelial-mesenchymal transition(EMT) in cultured human retinal pigment epithelial(RPE) cells. METHODS: Human RPE cells were inoculated on BioF ex 6-well plates and RPE cells received 0, 1, 2, 3, or 4 mild stretch injuries delivered 3h apart after 24h of culture. The device of mechanical stress parameters were set to sine wave, frequency 1 Hz, stretch strength 20%. For treatment with TGF-β2, when the inoculated RPE cells in 6-well plates were around 60% confluent, serum was reduced to 0 for 12h and recombinant human TGF-β2(0, 1, 5, 10 ng/mL)was added for 48h. α-SMA, Vimentin and N-Cadherin, fibronectin proteins expressions were detected by Western blotting, confocal cell immunofluorescence and quantitative real-time polymerase chain reaction(q RT-PCR). Then we detected the change of mi RNA-29b and ascertained the changes of phosphatidylinositol 3-kinase-serine threonine protein kinase(PI3K/Akt) pathway after RPE cells were stretched by the device of mechanical stress and induced by TGF-β2 by Western blotting, confocal cell immunofluorescence and qR T-PCR. RESULTS: Mechanical stress induce EMT and activate the PI3K/Akt pathway in ways that lead to the EMT process. TGF-β2 induce RPE cells EMT and in a certain range and TGF-β2 decrease the miR NA-29b expression in RPE cells, and the inhibitory effect is more obvious with the increase of TGF-β2 concentration. CONCLUSION: Our findings are crucial steps in determining the critical roles of the PI3K/Akt signaling pathway and mi RNA-29b in pathogenesis of proliferative vitreoretinopathy(PVR) which may be a potential target for preventing or treating PVR.

Side Population Cells in Human Gallbladder Cancer Cell Line GBC-SD Regulated by TGF-β-induced Epithelial-mesenchymal Transition

Mounting evidence has shown that side population （SP） cells are enriched for cancer stem cells （CSCs） responsible for cancer malignancy. In this study, SP technology was used to isolate a small subpopulation of SP cells in human gallbladder cancer cell line GBC-SD, and SP cells which had superior potential for proliferation in vitro and tumorigenesis in vivo were identified. Importantly, the abundance of GBC-SD SP cells was increased by a transforming growth factor-β （TGF-β）-induced epithelial-mesenchymal transition （EMT）, and this effect was accompanied with a strong up-regulation of ABCG2 mRNA expression, and a decreased sensitivity to mitoxantrone. SP cells were restored upon the removal of TGF-β and the reversion of the cells to an epithelial phenotype, and smad3-specific siRNA reduced SP abundance in response to TGF-β. In conclusion, TGF-β-induced EMT by smad-dependent signaling pathway promotes cancer development and anti-cancer drug resistant phenotype by augmenting the abundance of GBC-SD SP cells, and a better understanding of mechanisms involved in TGF-β-induced EMT may provide a novel strategy for preventing cancer progression.

Can a fibrotic liver afford epithelial-mesenchymal transition?

The question whether epithelial-mesenchymal transition (EMT) occurs during liver fibrogenesis is a controversial issue. In vitro studies confirm that hepatocytes or cholangiocytes undergo EMT upon transforming growth factor beta (TGF-beta) stimulation, whereas in vivo experiments based on genetic fate mapping of specific cell populations suggest that EMT does not occur in fibrotic animal models. In this review we present current data supporting or opposing EMT in chronic liver disease and discuss conditions for the occurrence of EMT in patients. Based on the available data and our clinical observations we hypothesize that EMT-like alterations in liver cirrhosis are a side effect of high levels of TGF-beta and other pro-fibrotic mediators rather than a biological process converting functional parenchyma, i.e., hepatocytes, into myofibroblasts at a time when essential liver functions are deteriorating.

Inhibition of TGF-β2-induced migration and epithelial-mesenchymal transition in ARPE-19 by sulforaphane

AIM: To investigate the effects of sulforaphane(SFN) on transforming growth factor(TGF)-β2 stimulated migration and epithelial-mesenchymal transition(EMT) in ARPE-19 cells.METHODS: ARPE-19 cells were cultured in the presence or absence of SFN or TGF-β2. SFN toxicity was assessed by performing a lactate dehydrogenase assay(LDH) and 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium(MTS) assays, and cell migration was evaluated by Transwell migration assay. Actin stress fiber formation in ARPE-19 cells was determined using immunofluorescence analysis. Immunoblotting analysis was used to determine fibronectin and α-smooth muscle actin expressions along with the degree of Smad and Akt phosphorylation.RESULTS: SFN inhibited ARPE-19 migration. Additionally, SFN attenuated TGF-β2-induced appearance of actin stress fibers as well as fibronectin and α-smooth muscle actin expressions in these cells. SFN also hindered the TGF-β2-stimulated phosphorylation of Smad2, Smad3, and Akt. SFN showed no cytotoxicity towards ARPE-19 cells. CONCLUSION: SFN inhibits TGF-β2-stimulated migration and EMT in ARPE-19 cells, probably by preventing the establishment of actin stress fibers and Akt and Smad2/3 signaling.

D-tryptophan triggered epithelial-mesenchymal transition by activating TGF-βsignaling pathway

D-tryptophan is a special kind of nonprotein amino acid showing multiple physiological functions,but the detailed mechanisms are not fully revealed,impairing its further development and applications.This work was to investigate D-tryptophan physiological function and demonstrate the underlying mechanisms.D-tryptophan suppressed HaCaT cell proliferation but increased cell migration.Specifically,D-tryptophan decreased E-cadherin and increased Snail,Twist,and Slug expression,resulting in the development of an epithelial-mesenchymal transitions(EMT)phenomenon.Moreover,D-tryptophan promoted the expression of transforming growth factor-β(TGF-β)1,and Smad4 knockout damages D-tryptophan’s ability.These results indicated that D-tryptophan stimulated HaCaT cells to produce TGF-β1 and thus activated the TGF-β/Samd pathway,resulting in the triggering of EMT.This study revealed the molecular mechanisms of D-tryptophan activity,provided D-tryptophan as a potential approach for cancer treatment,wound healing,organ development and other relevant applications.

番泻叶苷A对糖尿病肾病大鼠足细胞自噬的影响

目的探究番泻叶苷A(sennoside A,SA)对糖尿病肾病(diabetic nephropathy,DN)大鼠足细胞自噬及上皮-间质转化(EMT)的影响及可能的作用机制。方法随机选择10只雄性Wistar大鼠作为正常组,剩余大鼠尾静脉注射55 mg·kg^(−1)链脲佐菌素(streptozotocin,STZ)诱导DN大鼠模型。将成模大鼠随机分为模型组、SA低剂量组、SA高剂量组及贝那普利组,每组10只。SA低剂量组、SA高剂量组大鼠每日分别灌胃给予SA 40、80 mg·kg^(−1),贝那普利组大鼠每日灌服给予盐酸贝那普利10 mg·kg^(−1),模型组及正常组大鼠每日灌服等量生理盐水,连续给药21 d。检测24 h尿白蛋白(albumin,Alb)含量、大鼠空腹血糖(fasting blood glucose,FBG)、血肌酐(serum creatinine,Scr)和血尿素氮(blood urea nitrogen,BUN)水平;染色观察肾组织学变化;透射电镜观察肾脏组织自噬体形成情况;蛋白印迹法(Western blotting)检测肾组织中微管相关蛋白1轻链3(icrotubule associated protein 1 light chain 3,LC3)、Bcl-2相互作用蛋白1(Bcl-2 interacting protein 1,Beclin-1)、E-钙黏蛋白(E-cadherin,E-cad)、波形蛋白(vimentin,Vim)、沉默信息调节因子1(silencing information regulator 1,Sirt1)和肾病蛋白nephrin蛋白的相对表达水平。结果与正常组比较,其他4组大鼠24 h Alb含量、FBG及Scr、BUN水平升高,肾小球和肾小管发生病理损伤,胶原纤维及糖原明显沉积,肾小球系膜及基底膜增厚,肾组织中自噬体数量减少,LC3Ⅱ/LC3Ⅰ比值、Beclin-1、E-cad、nephrin及Sirt1蛋白的相对表达量降低,Vim蛋白的相对表达量升高(P<0.05);与模型组比较,3个给药组大鼠24 h Alb含量、FBG及Scr、BUN水平降低,肾小球和肾小管病理损伤情况呈不同程度减轻,胶原纤维及糖原沉积减弱,肾小球系膜及基底膜增厚情况改善,自噬体数量增加,LC3Ⅱ/LC3Ⅰ比值、Beclin-1、E-cad、nephrin及Sirt1蛋白的相对表达量升高,Vim蛋白的相对表达量降低(P<0.05);SA低剂量组、SA高剂量组及贝那普利组对DN大鼠的作用效果逐渐增强(P<0.05)。结论SA可改善DN大鼠肾功能障碍,其作用机制可能与激活Sirt通路进而促进足细胞自噬并减轻EMT有关。

基于足细胞上皮-间充质转化探讨中医药对慢性肾脏疾病作用机制及研究进展

足细胞作为肾脏高能量需求的高度特化上皮细胞,对维持肾小球滤过屏障的完整性至关重要。上皮-间质转分化作为足细胞损伤的重要形式,易导致肾小球滤过功能障碍影响多种慢性肾脏疾病的发生和进展。因此未来针对足细胞上皮-间充质转化是治疗慢性肾脏疾病的重要研究方向。黄芪、雷公藤、三七、蝉花等中药可通过作用TGF-β1/Smad、Wnt/β-catenin、Notch等信号通路抑制足细胞上皮-间充质转化,从而起到保护肾脏的作用。因此,本研究拟从足细胞上皮-间充质转化角度对中医药治疗慢性肾脏疾病作用机制及研究进展进行综述,以期为中医药在慢性肾脏疾病临床治疗中的应用提供科学依据。

Subretinal fibrosis secondary to neovascular age-related macular degeneration:mechanisms and potential therapeutic targets

Subretinal fibrosis is the end-stage sequelae of neovascular age-related macular degeneration.It causes local damage to photoreceptors,retinal pigment epithelium,and choroidal vessels,which leads to permanent central vision loss of patients with neovascular age-related macular degeneration.The pathogenesis of subretinal fibrosis is complex,and the underlying mechanisms are largely unknown.Therefore,there are no effective treatment options.A thorough understanding of the pathogenesis of subretinal fibrosis and its related mechanisms is important to elucidate its complications and explore potential treatments.The current article reviews several aspects of subretinal fibrosis,including the current understanding on the relationship between neovascular age-related macular degeneration and subretinal fibrosis;multimodal imaging techniques for subretinal fibrosis;animal models for studying subretinal fibrosis;cellular and non-cellular constituents of subretinal fibrosis;pathophysiological mechanisms involved in subretinal fibrosis,such as aging,infiltration of macrophages,different sources of mesenchymal transition to myofibroblast,and activation of complement system and immune cells;and several key molecules and signaling pathways participating in the pathogenesis of subretinal fibrosis,such as vascular endothelial growth factor,connective tissue growth factor,fibroblast growth factor 2,platelet-derived growth factor and platelet-derived growth factor receptor-β,transforming growth factor-βsignaling pathway,Wnt signaling pathway,and the axis of heat shock protein 70-Toll-like receptors 2/4-interleukin-10.This review will improve the understanding of the pathogenesis of subretinal fibrosis,allow the discovery of molecular targets,and explore potential treatments for the management of subretinal fibrosis.

Degradation of FAK-targeting by proteolytic targeting chimera technology to inhibit the metastasis of hepatocellular carcinoma

Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expression of focal adhesion kinase(FAK),which increases the risk of metastasis and recurrence.Nevertheless,the efficacy of FAK phosphorylation inhibitors is currently limited.Thus,investigating the mechanisms by which FAK affects HCC metastasis to develop targeted therapies for FAK may present a novel strategy to inhibit HCC metastasis.This study examined the correlation between FAK expression and the prognosis of HCC.Additionally,we explored the impact of FAK degradation on HCC metastasis through wound healing experiments,transwell invasion experiments,and a xenograft tumor model.The expression of proteins related to epithelial-mesenchymal transition(EMT)was measured to elucidate the underlying mechanisms.The results showed that FAK PROTAC can degrade FAK,inhibit the migration and invasion of HCC cells in vitro,and notably decrease the lung metastasis of HCC in vivo.Increased expression of E-cadherin and decreased expression of vimentin indicated that EMT was inhibited.Consequently,degradation of FAK through FAK PROTAC effectively suppressed liver cancer metastasis,holding significant clinical implications for treating liver cancer and developing innovative anti-neoplastic drugs.

Research Progress of circRNAs during Epithelial- Mesenchymal Transition of Hepatocellular Carcinoma

Hepatocellular carcinoma is prone to invasion and metastasis.It often receives a low diagnosis rate in the early stage but has an extremely high mortality rate.Epithelial-mesenchymal transformation(EMT)is a key factor in promoting tumor cell invasion and metastasis.Circular RNA(circRNA)is involved in regulating EMT in hepatocarcinoma cells through multiple pathways,thereby affecting the occurrence and progression of hepatocellular carcinoma.This article mainly reviews the research progress of circRNA related to EMT core transcription factors,circRNA that promotes EMT in liver cancer,and circRNA that inhibits EMT in liver cancer.

Regulatory role of the transforming growth factor-β signaling pathway in the drug resistance of gastrointestinal cancers

Gastrointestinal(GI)cancer,including esophageal,gastric,and colorectal cancer,is one of the most prevalent types of malignant carcinoma and the leading cause of cancer-related deaths.Despite significant advances in therapeutic strategies for GI cancers in recent decades,drug resistance with various mechanisms remains the prevailing cause of therapy failure in GI cancers.Accumulating evidence has demonstrated that the transforming growth factor(TGF)-βsignaling pathway has crucial,complex roles in many cellular functions related to drug resistance.This review summarizes current knowledge regarding the role of the TGF-βsignaling pathway in the resistance of GI cancers to conventional chemotherapy,targeted therapy,immunotherapy,and traditional medicine.Various processes,including epithelial-mesenchymal transition,cancer stem cell development,tumor microenvironment alteration,and microRNA biogenesis,are proposed as the main mechanisms of TGF-β-mediated drug resistance in GI cancers.Several studies have already indicated the benefit of combining antitumor drugs with agents that suppress the TGF-βsignaling pathway,but this approach needs to be verified in additional clinical studies.Moreover,the identification of potential biological markers that can be used to predict the response to TGF-βsignaling pathway inhibitors during anticancer treatments will have important clinical implications in the future.

The progression of epithelial-mesenchymal transformation in gliomas

Epithelial-mesenchymal transformation(EMT) is a coordinated process in which polarized epithelial cells are induced to lose adhesion from the basement membrane and obtain the properties of mesenchymal cells, including invasion and metastasis. It has been proved that EMT greatly contributes to the invasion and therapeutic resistance of various solid human cancers. However, the role of EMT in brain glioma has not yet been fully clarified. So in this review, we mainly elaborate the latest progression about the related regulatory transcription factors, key signaling pathways and microRNAs (miRNAs) of EMT in gliomas.

NADPH Oxidase-Dependent Formation of Reactive Oxygen Species Contributes to Transforming Growth Factor β1-Induced Epithelial-Mesenchymal Transition in Rat Peritoneal Mesothelial Cells,and the Role of Astragalus Intervention

Objective： To investigate the role of nicatinamide-adenine dinucleotide phosphate （NADPH） oxidase- dependent formation of reactive oxygen species （ROS） in the transforming growth factor β1 （TGF-β 1）-induced epithelial-mesenchymal transition （EMT） in rat peritoneal mesothelial ceils （RPMCs）, and the effect of Astragalus injection （AGI） intervention. Methods： Primary RPMCs were cultured to the second generation in vitro. After synchronization for 24 h, the calls were randomly assigned to the following groups： control （Group A）, AGI （2 g/mL; Group B）, TGF- β1 （10 ng/mL; Group C）, TGF- β1 （10 ng/mL） ＋ AGI （2 g/mL; Group D; pretreated for 1 h with AGI before TGF-β 1 stimulation）. Reverse transcription-polymerase chain reaction （RT-PCR） and Westem blot analysis were employed to evaluate the mRNA and protein expression of the NADPH oxidase subunit p67phox, e-smooth muscle actin （α -SMA） and E-cadherin. The dichlorofluorescain-sensitive cellular ROS levels were measured by a fluorometric assay and confocal microscopy. Results： TGF- β1 significantly induced NADPH oxidase subunit p67phox mRNA and protein expression in RPMCs, as well as inducing the production of intracellular ROS. AGI inhibited this TGF- β1-induced up-regulation by 39.3% and 47.8%, respectively （P〈0.05）, as well as inhibiting the TGF- β 1- induced ROS generation by 56.3% （P〈0.05）. TGF- β 1 also induced α-SMA mRNA and protein expression, and down-regulated E-cadhedn mRNA and protein expression （P〈0.05）. This effect was suppressed by AGI （P〈0.05）. Conclusions： NADPH oxidase-dependent formation of ROS may mediate the TGF- β1-dependent EMT in RPMCs. AGI could inhib/t this process, providing a theoretical basis for AGI in the prevention of peritoneal fibrosis.