title: The mechanism of epithelial-mesenchymal transition induced by TGF-β1 in neuroblastoma cells.
abstract: Neuroblastoma is the second most common extracranial malignant solid tumor that occurs in childhood, and metastasis is one of the major causes of death in neuroblastoma patients. The epithelial-mesenchymal transition (EMT) is an important mechanism for both the initiation of tumor invasion and subsequent metastasis. Therefore, this study investigated the mechanism by which transforming growth factor (TGF)-β1 induces EMT in human neuroblastoma cells. Using quantitative RT-qPCR and western blot analyses, we found that the mRNA and protein expression levels of E-cadherin were significantly decreased, whereas that of α-SMA was significantly increased after neuroblastoma cells were treated with different concentrations of TGF-β1. A scratch test and Transwell migration assay revealed that cell migration significantly and directly correlated with the concentration of TGF-β1 indicating that TGF-β1 induced EMT in neuroblastoma cells and led to their migration. Inhibiting Smad2/3 expression did not affect the expression of the key molecules involved in EMT. Further investigation found that the expression of the glioblastoma transcription factor (Gli) significantly increased in TGF-β1-stimulated neuroblastoma cells undergoing EMT, accordingly, interfering with Gli1/2 expression inhibited TGF-β1-induced EMT in neuroblastoma cells. GANT61, which is a targeted inhibitor of Gli1 and Gli2, decreased cell viability and promoted cell apoptosis. Thus, TGF-β1 induced EMT in neuroblastoma cells to increase their migration. Specifically, EMT induced by TGF-β1 in neuroblastoma cells did not depend on the Smad signaling pathway, and the transcription factor Gli participated in TGF-β1-induced EMT independent of Smad signaling.
authors.affiliation: Department of Hematology/Oncology, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai 200040, P.R. China.
authors.forename: Jing-Bo
authors.initials: JB
authors.lastname: Shao
authors.affiliation: Department of Central Laboratory, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai 200040, P.R. China.
authors.forename: Zhi-Mei
authors.initials: ZM
authors.lastname: Gao
authors.affiliation: Department of Nephrology, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai 200040, P.R. China.
authors.forename: Wen-Yan
authors.initials: WY
authors.lastname: Huang
authors.affiliation: Department of General Surgery, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai 200040, P.R. China.
authors.forename: Zhi-Bao
authors.initials: ZB
authors.lastname: Lu
mesh_terms: D000199:Actins / Q000235:genetics; D015703:Antigens, CD; D017209:Apoptosis / Q000187:drug effects; D015820:Cadherins / Q000096:biosynthesis / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D002470:Cell Survival / Q000187:drug effects; D058750:Epithelial-Mesenchymal Transition / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D051741:Kruppel-Like Transcription Factors / Q000037:antagonists & inhibitors / Q000235:genetics*; D009447:Neuroblastoma / Q000235:genetics* / Q000473:pathology; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors / Q000235:genetics*; D011725:Pyridines / Q000008:administration & dosage; D011743:Pyrimidines / Q000008:administration & dosage; D012333:RNA, Messenger / Q000096:biosynthesis; D015398:Signal Transduction / Q000235:genetics; D051785:Smad Proteins / Q000235:genetics; D053773:Transforming Growth Factor beta1 / Q000096:biosynthesis / Q000235:genetics*; D000071676:Zinc Finger Protein GLI1 / Q000037:antagonists & inhibitors / Q000235:genetics*; D000075746:Zinc Finger Protein Gli2
chemical_list: C541116:ACTA2 protein, human; D000199:Actins; D015703:Antigens, CD; C513384:CDH1 protein, human; D015820:Cadherins; C551027:GANT 61; C400551:GLI1 protein, human; C082593:GLI2 protein, human; D051741:Kruppel-Like Transcription Factors; D009687:Nuclear Proteins; D011725:Pyridines; D011743:Pyrimidines; D012333:RNA, Messenger; D051785:Smad Proteins; D053773:Transforming Growth Factor beta1; D000071676:Zinc Finger Protein GLI1; D000075746:Zinc Finger Protein Gli2