FPR1 Antagonist (BOC-MLF) Inhibits Amniotic Epithelial-mesenchymal Transition

Objective:Premature rupture of membranes(PROM)is a common pregnancy disorder that is closely associated with structural weakening of fetal membranes.Studies have found that formyl peptide receptor 1(FPR1)activates inflammatory pathways and amniotic epithelial-mesenchymal transition(EMT),stimulates collagen degradation,and leads to membrane weakening and membrane rupture.The purpose of this study was to investigate the anti-inflammatory and EMT inhibitory effects of FPR1 antagonist(BOC-MLF)to provide a basis for clinical prevention of PROM.Methods:The relationship between PROM,FPR1,and EMT was analyzed in human fetal membrane tissue and plasma samples using Western blotting,PCR,Masson staining,and ELISA assays.Lipopolysaccharide(LPS)was used to establish a fetal membrane inflammation model in pregnant rats,and BOC-MLF was used to treat the LPS rat model.We detected interleukin(IL)-6 in blood from the rat hearts to determine whether the inflammatory model was successful and whether the anti-inflammatory treatment was effective.We used electron microscopy to analyze the structure and collagen expression of rat fetal membrane.Results:Western blotting,PCR and Masson staining indicated that the expression of FPR1 was significantly increased,the expression of collagen was decreased,and EMT appeared in PROM.The rat model indicated that LPS caused the collapse of fetal membrane epithelial cells,increased intercellular gaps,and decreased collagen.BOC-MLF promoted an increase in fetal membrane collagen,inhibited EMT,and reduced the weakening of fetal membranes.Conclusion:The expression of FPR1 in the fetal membrane of PROM was significantly increased,and EMT of the amniotic membrane was obvious.BOC-MLF can treat inflammation and inhibit amniotic EMT.

LncRNA MEG3 Inhibits the Epithelial-mesenchymal Transition of Bladder Cancer Cells through the Snail/E-cadherin Axis

Objective This study aimed to investigate the role of the long noncoding RNA(lncRNA)maternally expressed gene 3(MEG3)in the epithelial-mesenchymal transition(EMT)of bladder cancer cells and the potential mechanisms.Methods Cell invasion,migration,and wound healing assays were conducted to assess the effects of MEG3 on the invasive and migratory capabilities of bladder cancer cells.The expression levels of E-cadherin were measured using Western blotting,RT-qPCR,and dual luciferase reporter assays.RNA immunoprecipitation and pull-down assays were performed to investigate the interactions between MEG3 and its downstream targets.Results MEG3 suppressed the invasion and migration of bladder cancer cells and modulated the transcription of E-cadherin.The binding of MEG3 to the zinc finger region of the transcription factor Snail prevented its ability to transcriptionally repress E-cadherin.Additionally,MEG3 suppressed the phosphorylation of extracellular regulated protein kinase(ERK),c-Jun N-terminal kinase(JNK),and P38,thereby decreasing the expression of Snail and stimulating the expression of E-cadherin.Conclusion MEG3 plays a vital role in suppressing the EMT in bladder cancer cells,indicating its potential as a promising therapeutic target for the treatment of bladder cancer.

CALD1 facilitates epithelial-mesenchymal transition progression in gastric cancer cells by modulating the PI3K-Akt pathway

BACKGROUND CALD1 has been discovered to be abnormally expressed in a variety of malignant tumors,including gastric cancer(GC),and is associated with tumor progression and immune infiltration;however,the roles and mechanisms of CALD1 in epithe-lial-mesenchymal transition(EMT)in GC are unknown.AIM To investigate the role and mechanism of CALD1 in GC progression,invasion,and migration.METHODS In this study,the relationship between CALD1 and GC,as well as the possible network regulatory mechanisms of CALD1,was investigated by bioinformatics and validated by experiments.CALD1-siRNA was synthesized and used to trans-fect GC cells.Cell activity was measured using the CCK-8 method,cell migration and invasive ability were measured using wound healing assay and Transwell assay,and the expression levels of relevant genes and proteins in each group of cells were measured using qRT-PCR and Western blot.A GC cell xenograft model RESULTS Bioinformatics results showed that CALD1 was highly expressed in GC tissues,and CALD1 was significantly higher in EMT-type GC tissues than in tissues of other types of GC.The prognosis of patients with high expression of CALD1 was worse than that of patients with low expression,and a prognostic model was constructed and evaluated.The experimental results were consistent with the results of the bioinformatics analysis.The expression level of CALD1 in GC cell lines was all higher than that in gastric epithelial cell line GES-1,with the strongest expression found in AGS and MKN45 cells.Cell activity was significantly reduced after CALD1-siRNA trans-fection of AGS and MKN45 cells.The ability of AGS and MKN45 cells to migrate and invade was reduced after CALD1-siRNA transfection,and the related mRNA and protein expression was altered.According to bioinfor-matics findings in GC samples,the CALD1 gene was significantly associated with the expression of members of the PI3K-AKT-mTOR signaling pathway as well as the EMT signaling pathway,and was closely related to the PI3K-Akt signaling pathway.Experimental validation revealed that upregulation of CALD1 increased the expression of PI3K,p-AKT,and p-mTOR,members of the PI3K-Akt pathway,while decreasing the expression of PTEN;PI3K-Akt inhibitor treatment decreased the expression of PI3K,p-AKT,and p-mTOR in cells overexpressing CALD1(still higher than that in the normal group),but increased the expression of PTEN(still lower than that in the normal group).CCK-8 results revealed that the effect of CALD1 on tumor cell activity was decreased by the addition of the inhibitor.Scratch and Transwell experiments showed that the effect of CALD1 on tumor cell migration and invasion was weakened by the addition of the PI3K-Akt inhibitor.The mRNA and protein levels of EMT-related genes in AGS and MKN45 cells were greatly altered by the overexpression of CALD1,whereas the effect of overex-pression of CALD1 was significantly weakened by the addition of the PI3K-Akt inhibitor.Animal experiments showed that tumour growth was slow after inhibition of CALD1,and the expression of some PI3K-Akt and EMT pathway proteins was altered.CONCLUSION Increased expression of CALD1 is a key factor in the progression,invasion,and metastasis of GC,which may be associated with regulating the PI3K-Akt pathway to promote EMT.

circPVT1 promotes silica-induced epithelial-mesenchymal transition by modulating the miR-497-5p/TCF3 axis

Epithelial-mesenchymal transition(EMT)is a vital pathological feature of silica-induced pulmonary fibrosis.However,whether circRNA is involved in the process remains unclear.The present study aimed to investigate the role of circPVT1 in the silica-induced EMT and the underlying mechanisms.We found that an elevated expression of circPVT1 promoted EMT and enhanced the migratory capacity of silica-treated epithelial cells.The isolation of cytoplasmic and nuclear separation assay showed that circPVT1 was predominantly expressed in the cytoplasm.RNA immunoprecipitation assay and RNA pull-down experiment indicated that cytoplasmic-localized circPVT1 was capable of binding to miR-497-5p.Furthermore,we found that miR-497-5p attenuated the silica-induced EMT process by targeting transcription factor 3(TCF3),an E-cadherin transcriptional repressor,in the silica-treated epithelial cells.Collectively,these results reveal a novel role of the circPVT1/miR-497-5p/TCF3 axis in the silica-induced EMT process in lung epithelial cells.Once validated,this finding may provide a potential theoretical basis for the development of interventions and treatments for pulmonary fibrosis.

VX-509 attenuates the stemness characteristics of colorectal cancer stem-like cells by regulating the epithelial-mesenchymal transition through Nodal/Smad2/3 signaling

BACKGROUND Colorectal cancer stem cells(CCSCs)are heterogeneous cells that can self-renew and undergo multidirectional differentiation in colorectal cancer(CRC)patients.CCSCs are generally accepted to be important sources of CRC and are responsible for the progression,metastasis,and therapeutic resistance of CRC.Therefore,targeting this specific subpopulation has been recognized as a promising strategy for overcoming CRC.AIM To investigate the effect of VX-509 on CCSCs and elucidate the underlying mechanism.METHODS CCSCs were enriched from CRC cell lines by in conditioned serum-free medium.Western blot,Aldefluor,transwell and tumorigenesis assays were performed to verify the phenotypic characteristics of the CCSCs.The anticancer efficacy of VX-509 was assessed in HCT116 CCSCs and HT29 CCSCs by performing cell viability analysis,colony formation,sphere formation,flow cytometry,and western blotting assessments in vitro and tumor growth,immunohistochemistry and immunofluorescence assessments in vivo.RESULTS Compared with parental cells,sphere cells derived from HCT116 and HT29 cells presented increased expression of stem cell transcription factors and stem cell markers and were more potent at promoting migration and tumori-genesis,demonstrating that the CRC sphere cells displayed CSC features.VX-509 inhibited the tumor malignant biological behavior of CRC-stem-like cells,as indicated by their proliferation,migration and clonality in vitro,and suppressed the tumor of CCSC-derived xenograft tumors in vivo.Besides,VX-509 suppressed the CSC character-istics of CRC-stem-like cells and inhibited the progression of epithelial-mesenchymal transition(EMT)signaling in vitro.Nodal was identified as the regulatory factor of VX-509 on CRC stem-like cells through analyses of differen-tially expressed genes and CSC-related database information.VX-509 markedly downregulated the expression of Nodal and its downstream phosphorylated Smad2/3 to inhibit EMT progression.Moreover,VX-509 reversed the dedifferentiation of CCSCs and inhibited the progression of EMT induced by Nodal overexpression.CONCLUSION VX-509 prevents the EMT process in CCSCs by inhibiting the transcription and protein expression of Nodal,and inhibits the dedifferentiated self-renewal of CCSCs.

Research p rogress on Chinese herbal drugs in the TGF- β signaling pathway involved in epithelial-mesenchymal transition

Epithelial-mesenchymal transition is a well-defined,reversible process in which epithelial cells lose their epithelial phenotype and acquire mesenchymal-like features.Epithelial-mesenchymal transition contributes significantly to the metastasis,invasion,and development of treatment resistance in cancer cells.There have been many studies on suppression of tumor epithelial-mesenchymal transition by Chinese medicine in recent years,mainly based on Chinese herbal drug monomers and compounds.In this review,we aim to describe the research progress on Chinese medicine in the t ransforming growth factor beta(T GF-β)sig naling pathway,we hope these will provide some guidance for further research on Chinese medicine targeting epithelial-mesenchymal transition.

Investigating the mechanism of action of Bu-Yang-Huan-Wu decoction in treating bleomycin-Induced pulmonary fibrosis through the epithelial-mesenchymal transition pathway

Background:To explore the effects and mechanisms of Bu-Yang-Huan-Wu Decoction on pulmonary fibrosis in mice.Methods:Forty-five C57BL/6J mice were randomly divided into three groups:Control,Model,and Bu-Yang-Huan-Wu Decoction.Pulmonary fibrosis was elicited in mice through a solitary intratracheal administration of 2.5 mg/kg bleomycin.For the control group,mice were given a solitary intratracheal administration of a comparable volume of PBS.Treatment began on the first day after the successful model establishment and lasted for 21 days.The survival rate and body weight of the mice were recorded daily,and on the 22nd day,bronchoalveolar lavage fluid was collected to determine total cells and total protein.The wet/dry weight ratio of lung tissue and hydroxyproline were measured.Lung tissue pathology was observed using hematoxylin and eosin staining and Masson staining.The mRNA expression of epithelial-mesenchymal transition-related proteins(E-cadherin and vimentin)was detected by RT-qPCR,and their protein expression was analyzed by western blot.Results:Compared to the model group,the Bu-Yang-Huan-Wu Decoction treatment notably enhanced both the survival rate and body weight in pulmonary fibrosis mice,significantly reduced lung tissue wet/dry weight ratio,total cells,and protein in bronchoalveolar lavage fluid,and hydroxyproline content.The pathological morphology of lung tissue was significantly improved,with increased expression of the epithelial cell marker E-cadherin mRNA and protein,and decreased expression of the mesenchymal cell marker vimentin mRNA and protein.Conclusion:Bu-Yang-Huan-Wu Decoction can improve the degree of bleomycin-induced pulmonary fibrosis in mice by inhibiting epithelial-mesenchymal transition.

Induction of epithelial-mesenchymal transition (EMT) in human hepatocellular carcinoma after radiotherapy

Objective: Epithelial-mesenchymal transition (EMT) is a critical early event for the invasion and metastasis of many carcinomas. In the present study, we examined EMT markers in the residual cancer cells of hepatocellular carcinoma (HCC) after radiotherapy. Methods: Eight patients with large HCC who underwent hepatectomy with preoperative radiothera- py were studied. The expressions of E-cadherin and vimentin were determined immunohistochemically in the residual cancer cells of HCC following radiotherapy, and also in the pre-radiotherapy biopsy cancer cells. Results: Histological analysis showed that some residual cancer cells of HCC displayed an elongated spindle or fibroblast-like shape. The expression of E- cadherin was markedly reduced or negative in the spindle residual cancer cells, but the expression of vimentin significantly in- duced. However, the above changes were not found in the pre-radiotherapy biopsy cancer cells. Conclusion: EMT is induced in the residual cancer cells of HCC following radiotherapy, which may facilitate the systemic dissemination of cancer cells.

Correlation of Claudins6 (CLDN6) gene expression in meningioma tissue with the expression of matrix metalloproteinases (MMPs)/tissue inhibitors of matrix metalloproteinase (TIMPs) and epithelial-mesenchymal transition (EMT) genes

Objective:To study the correlation of Claudins6 (CLDN6) gene expression in meningioma tissue with the expression of matrix metalloproteinases (MMPs)/tissue inhibitors of matrix metalloproteinase (TIMPs) and epithelial-mesenchymal transition (EMT) genes.Methods:Meningioma tissue samples that were surgically removed in Yibin First People's Hospital between April 2014 and May 2017 were selected, normal arachnoid tissue samples that were collected from decompressive craniectomy in Yibin First People's Hospital during the same period were selected, and the expression of CLDN6, MMPs/TIMPs and EMT genes in tissues were determined.Results: CLDN6 protein expression in meningioma tissue was significantly lower than that in normal arachnoid tissue;EMMPRIN, MMP2, MMP9, Vimentin and N-cadherin protein expression in meningioma tissue were significantly higher than those in normal arachnoid tissue while TIMP1, TIMP2, E-cadherin andα-catenin protein expression were significantly lower than those in normal arachnoid tissue;EMMPRIN, MMP2, MMP9, Vimentin and N-cadherin protein expression in meningioma tissue with higher CLDN6 expression were significantly lower than those in meningioma tissue with lower CLDN6 expression while TIMP1, TIMP2, E-cadherin andα-catenin protein expression were significantly higher than those in meningioma tissue with lower CLDN6 expression. Conclusion: Lowly expressed CLDN6 gene in meningioma tissue can increase the hydrolysis activity of MMPs, induce epithelial-mesenchymal transition and thus promote the invasive growth of meningioma.

Epithelial-mesenchymal transition mediated tumourigenesis in the gastrointestinal tract

Epithelial-mesenchymal transition (EMT) is a highly conserved process that has been well characterised in embryogenesis. Studies have shown that the aberrant activation of EMT in adult epithelia can promote tumour metastasis by repressing cell adhesion molecules,including epithelial (E)-cadherin. Reduced intracellular adhesion may allow tumour cells to disseminate and spread throughout the body. A number of transcription proteins of the Snail superfamily have been implicated in EMT. These proteins have been shown to be over-expressed in advanced gastrointestinal (GI) tumours including oesophageal adenocarcinomas,colorectal carcinomas,gastric and pancreatic cancers,with a concomitant reduction in the expression of E-cadherin. Regulators of EMT may provide novel clinical targets to detect GI cancers early,so that cancers previously associated with a poor prognosis such as pancreatic cancer can be diagnosed before they become inoperable. Furthermore,pharmacological therapies designed to inhibit these proteins will aim to prevent local and distant tumour invasion.

Role of epithelial-mesenchymal transition in gastric cancer initiation and progression

Gastric cancer is one of the most common malignant tumors worldwide.Due to its intricate initiation and progression mechanisms,early detection and effective treatment of gastric cancer are difficult to achieve.The epithelial-mesenchymal transition(EMT)is characterized as a fundamental process that is critical for embryonic development,wound healing and fibrotic disease.Recent evidence has established that aberrant EMT activation in the human stomach is closely associated with gastric carcinogenesis and tumor progression.EMT activation endows gastric epithelial cells with increased characteristics of mesenchymal cells and reduces their epithelial features.Moreover,mesenchymal cells tend to dedifferentiate and acquire stem cell or tumorigenic phenotypes such as invasion,metastasis and apoptosis resistance as well as drug resistance during EMT progression.There are a number of molecules that indicate the stage of EMT(e.g.,E-cadherin,an epithelial cell biomarker);therefore,certain transcriptional proteins,especially E-cadherin transcriptional repressors,may participate in the regulation of EMT.In addition,EMT regulation may be associated with certain epigenetic mechanisms.The aforementioned molecules can be used as early diagnostic markers for gastric cancer,and EMT regulation can provide potential targets for gastric cancer therapy.Here,we review the role of these aspects of EMT in gastric cancer initiation and development.

Systematic review of the old and new concepts in the epithelial-mesenchymal transition of colorectal cancer

Epithelial-to-mesenchymal transition(EMT) is defined as the transformation of an epithelial cell into a spindle cell with the loss of membrane E-cadherin expression and the gain of mesenchymal markers positivity. In the field of colorectal cancer(CRC), first data about EMT was published in 1995 and more than 400 papers had been written up to March 2016. Most of them are focused on the molecular pathways and experimentally-proved chemoresistance. In the present article, an update in the field of EMT in CRC based on the review of the literature and personal experience of the authors is presented. The information about the molecular and immunohistochemical(IHC) particularities of these processes and their possible role in the prognosis of CRC were also up-dated. This article focuses on the IHC quantification of the EMT, the immunoprofile of tumor buds and on the relation between EMT, angiogenesis, and stem cells activation. The EMT-induced chemoresistance vs chemotherapyor radiotherapy-induced EMT and cellular senescence was also synthesized for both conventional and targeted therapy. As a future perspective, the EMTangiogenesis-stemness link could be used as a possible valuable parameter for clinical follow-up and targeted therapeutic oncologic management of patients with CRC. Association of dexamethasone and angiotensin converting enzyme inhibitors combined with conventional chemotherapies could have clinical benefits in patients with CRC. The main conclusion is that, although many studies have been published, the EMT features are still incompletely elucidated and newly discovered EMT markers provide confusing data in understanding this complicated process, which might have significant clinical impact.

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.

GSK3β inhibits epithelial-mesenchymal transition via the Wnt/β-catenin and PI3K/Akt pathways

AIM： To investigate the regulatory mechanism of glycogen synthase kinase 3β（GSK3β） in epithelialmesenchymal transition（EMT） process after proliferative vitreoretinopathy（PVR） induction. METHODS： Experimental PVR was induced by intravitreal injection of retinal pigment epithelium（RPE） cells in the eyes of rabbits. A PI3 K/Akt inhibitor（wortmannin） and a GSK3β inhibitor（Li Cl） were also injected at different time during PVR progress. Electroretinogram（ERG）, ocular fundus photographs, and B-scan ultrasonography were used to observe the PVR progress. Western blot test on the extracted retina were performed at 1, 2, 4 wk. The expression of the mesenchymal marker vimentin was determined by immunohistochemistry. Toxicity of wortmannin and Li Cl were evaluated by ERG and Td Tmediated d UTP nick-end labeling（TUNEL） assay. The vitreous was also collected for metabolomic analysis. RESULTS： Experimental PVR could significantly lead to EMT, along with the suppressed expression of GSK3β and the activation of Wnt/β-catenin and PI3 K/Akt pathways. It was verified that upregulating the expression of GSK3β could effectively inhibit EMT process by suppressing Wnt/β-catenin and PI3 K/Akt pathways. CONCLUSION： GSK3β effectively inhibits EMT via the Wnt/β-catenin and PI3 K/Akt pathways. GSK3β may be regarded as a promising target of experimental PVR inhibition.

Dexmedetomidine Attenuates High Glucose-induced HK-2 Epithelial-mesenchymal Transition by Inhibiting AKT and ERK

Objective To explore the protective effects of dexmedetomidine(Dex)against high glucose-induced epithelial-mesenchymal transition in HK-2 cells and relevant mechanisms.Methods HK-2 cells were exposed to either glucose or glucose+Dex for 6 h.The production of ROS,morphology of HK-2 cells,and cell cycle were detected.Moreover,the expression of AKT,p-AKT,ERK,pERK,PI3 K,E-Cadherin,Claudin-1,andα-SMA were determined and compared between HK-2 cells exposed to glucose and those exposed to both glucose and Dex with or without PI3 K/AKT pathway inhibitor LY294002 and ERK pathway inhibitor U0126.Results Compared with HK-2 cells exposed to high level of glucose,the HK-2 cells exposed to both high level of glucose and Dex showed:(1)lower level of ROS production;(2)cell morphology was complete;(3)more cells in G1 phase;(4)lower expression of p-AKT,p-ERK andα-SMA,higher expression of ECadherin and Claudin-1.PI3 K/AKT inhibitor LY294002 and ERK inhibitor U0126 decreased the expression of p-AKT,p-ERK andα-SMA,and increased the expression of E-Cadherin and Claudin-1.Conclusion Dex can attenuate high glucose-induced HK-2 epithelial-mesenchymal transition by inhibiting AKT and ERK.

Integrin-linked kinase overexpression promotes epithelial-mesenchymal transition via nuclear factor-κB signaling in colorectal cancer cells

AIM: To investigate the effect of integrin-linked kinase (ILK) on proliferation, metastasis, and invasion of the colorectal cancer cell line SW480.METHODS: In this study, the colorectal cancer cell line SW480 was stably transfected with ILK plasmids, and small interfering RNA (siRNA) was used to knockdown expression of nuclear factor (NF)-κB/p65. Methylthiazole tetrazolium (MTT) assay was performed to measure proliferation, and the wound healing migration assay and matrigel invasion assay were used to test the metastasis and invasion ability of SW480 cells. To explore the epithelial-mesenchymal transition (EMT) process, embryonic development, and the invasion and metastasis of tumors, the protein level of E-cadherin, vimentin, snail, and slug was detected by western blot. Immunofluorescence was also used to detect E-cadherin expression. Western blot was used to determine the level of phosphorylated-inhibitor of kappa B (IκB)a, inhibitor of gamma B (IγB)a, and nuclear factor kappa B (NF-κB) expressions and to explore the ILK signaling pathway.RESULTS: Western blot results revealed that ILK expression significantly increased when ILK was overexpressed in SW480 cells (P < 0.05). Proliferation, metastasis, and invasion ability were improved in the vector-ILK group compared to the vector group (P < 0.05). Immunofluorescence results revealed that E-cadherin fluorescence intensity decreased after ILK was overexpressed (P < 0.05). Western blot results revealed that the protein expression of E-cadherin was reduced, while vimentin, snail, and slug were upregulated when ILK was overexpressed in SW480 cells (P < 0.05). In order to determine the role of the NF-κB signaling pathway in ILK overexpression promoted EMT occurrence, we overexpressed ILK in SW480 cells and found that levels of NF-κB/p65 and cytoplasmic phosphorylated-IκBa were increased and that cytoplasmic IкBa levels were decreased compared to the control group (P < 0.05). Furthermore, NF-κB/p65 knockout revealed that E-cadherin was increased in the overexpressed ILK group.CONCLUSION: ILK overexpression improved the proliferation, metastasis, and invasion ability of SW480 cells, and this effect may be mediated by the NF-κB signaling pathway.

Epithelial-mesenchymal transition as a therapeutic target for overcoming chemoresistance in pancreatic cancer

Pancreatic cancer has one of the worst prognoses among all cancers due to the late manifestation of identifiable symptoms and high resistance to chemo- and radiation therapies. In recent years, a cancer development phase termed epithelial-mesenchymal transition(EMT) has gained increasing research focus. The process is implicated in tumour metastasis, and emerging evidence suggests EMT also contributes or induces chemoresistance in several cancers. Nevertheless, the applicability of therapeutic targeting of EMT faces many challenges. In this mini-review, we summarise the evidence supporting the role of EMT in pancreatic cancer progression, focusing particularly on its association with chemoresistance.

KAI1 reverses the epithelial-mesenchymal transition in human pancreatic cancer cells

Background: Epithelial-mesenchymal transition (EMT) plays an important role in pancreatic cancer (PC). In the present study, we investigated the effects of KAI1 gene overexpression on the EMT of human PC cell lines, MIA PaCa-2 and PACN-1. Methods: Plasmids overexpressing KAI1 and pCMV were transfected into MIA PaCa-2 and PACN-1 cells, respectively. After selection of differently transfected cells by G418, KAI1 protein levels were examined by Western blotting, and transfected cells were renamed as MIA PaCa-2-K, MIA PaCa-2-p, PACN-1-K and PACN-1-p. Wound healing and Transwell migration assays were then performed comparing the two groups of cells. EMT-related markers were analyzed by Western blotting. Results: The percentage of wound closure significantly decreased in MIA PaCa-2-K cells compared with MIA PaCa-2-p and MIA PaCa-2 cells after 24, 48 and 72 h ( P < 0.05). In PACN-1-K cells, the percentage of wound closure significantly decreased as well ( P < 0.05). Numbers of invading MIA PaCa-2, MIA PaCa-2-p and MIA PaCa-2-K cells were determined as 48.0 ±15.4, 50.0 ±12.4, and 12.0 ±3.8, respectively. The corresponding numbers of invading PACN-1, PACN-1-p and PACN-1-K cells were 29.0 ±10.6, 31.0 ±11.4, and 8.0 ±4.2, respectively. KAI1 overexpression induced a significant upregulation of E-cadherin and also significant downregulation of Snail, vimentin, matrix metalloproteinase 2 (MMP2) and MMP9 (all P < 0.05) in PC cells. Conclusions: KAI1 reversed EMT-related marker expression and inhibited migration and invasion of PC cells. Thus, KAI1 might represent a novel potential therapeutic target for PC.

MiR-301a transcriptionally activated by HIF-2αpromotes hypoxiainduced epithelial-mesenchymal transition by targeting TP63 in pancreatic cancer

BACKGROUND Pancreatic cancer(PC)is one of the deadliest cancers worldwide.PC metastasis involves a complex set of events,including epithelial-mesenchymal transition(EMT),that increase tumor cell invasiveness.Recent evidence has shown that hypoxia is a major EMT regulator in pancreatic cancer cells and facilitates metastasis;however,the mechanisms remain elusive.AIM To investigate the role of miR-301a in hypoxia-induced EMT in PC cells.METHODS Real-time PCR and Western blot analysis were used to detect the expression of miR-301a and EMT markers in PDAC cells cultured in hypoxic and normoxic conditions.Western blot analysis was used to detect the expression of EMT markers in PDAC cells with miR-301a overexpression.Wound healing assay and Transwell assay were used to detect the migration capabilities of PDAC cells with miR-301a overexpression and knockout.Luciferase assay was used to detect the miR-301a promoter and the 3’untranslated region activity of TP63.Orthotopic PC mouse models were used to study the role of miR-301a in metastasis of PDAC cells in vivo.In situ hybridization assay was used to detect the expression of miR-301a in PDAC patient samples(adjacent paratumor and paired tumor tissues).RESULTS Hypoxic environment could directly promote the EMT of PC cells.The expression level of miR-301a was increased in a HIF2αdependent manner in hypoxia-cultured CFPAC-1 and BxPC-3 cells.Overexpression of miR-301a enhanced the hypoxia-induced EMT of PC cells,while knocking out miR-301a result in the suppression of hypoxia-induced EMT.TP63 was a direct target of miR-301a and involved in the metastatic process of PC cells.Furthermore,miR-301a upregulation facilitated PDAC distant metastasis and lymph node metastasis in vivo.Additionally,miR-301a overexpression was indicative of aggressive clinicopathological behaviors and poor prognosis.CONCLUSION The newly identified HIF-2α-miR301a-TP63 signaling pathway may play a crucial role in hypoxia-induced EMT in PDAC cells.

In vitro inhibition of proliferation,migration and epithelial-mesenchymal transition of human lens epithelial cells by fasudil

AIM： To study the potential role of fasudil as a treatment for posterior capsular opacification（PCO） of the human crystalline lens.METHODS： Human lens epithelial cells（HLECs; line SRA01/04） was exposed to transforming growth factor-β2（TGF-β2） to induce the process of epithelial-mesenchymal transition（EMT）. Fasudil was applied to the cell samples. Its effect on overall HLECs proliferation and migration was studied, as was its influence on EMT induction by TGF-β2 using cell migration assay, MTT colorimetric assay and Western blot assay.RESULTS： Fasudil inhibited the proliferation of SRA01/04. Its effect was time-and concentration-dependent. The migration of SRA01/04 cells was significantly reduced 24-72 h after fasudil treatment, and the half maximal inhibitory concentration（IC50） was 22.37 μmol/mL at 72 h. Reversal of the elongated, fibroblast-like shape changes induced by TGF-β2 in SRA01/04 cells was observed. Fasudil up-regulated the expression of Connexin43 protein and down-regulated the expression of α-SMA protein compared with the cells treated with TGF-β2. Furthermore, when exposed to fasudil, the phosphorylation of Rhoassociated protein kinase（Rock） and myosin light chain（MLC） could not be activated in the cell preparations.CONCLUSION： Fasudil suppresses the proliferation and migration of SRA01/04 cells, and inhibits the process of EMT induced by TGF-β2. These results suggest that fasudil may serve as a therapeutic agent for PCO.