中华医学杂志（英文版）2012，Vol.125Issue(18)：3312-3317,6.DOI:10.3760/cma.j.issn.0366-6999.2012.18.021
Type 2 epithelial mesenchymal transition in vivo: truth or pitfalls?
Type 2 epithelial mesenchymal transition in vivo: truth or pitfalls?
摘要
Abstract
Epithelial-mesenchymal transition (EMT) is a process by which fully differentiated epithelial cells undergo a phenotypic conversion and assume a mesenchymal cell phenotype,including elongated morphology,enhanced migratory and invasiveness capacity,and greatly increased production of extracellular matrix (ECM) components.The EMTs associated with wound healing,tissue regeneration,and organ fibrosis are termed as type 2 EMT.Over the past two decades,emerging evidence suggested that injured epithelial cells,via type 2 EMT,may serve as important sources of fibroblasts and contribute to organ fibrosis,such as kidney,liver,lung and eyes.There is perhaps no doubt that adult epithelial cells can undergo EMT in vitro in response to transforming growth factor (TGF)-β1 and other inflammatory or pro-fibrotic stimuli.However,whether type 2 EMT really occurs in vivo,whethers it is actually a source of functional and activated interstitial fibroblasts and whether it contributes to tissue fibrosis have already been the subjects of heated debate.In this review,we will describe the main features of EMT,the major findings of type 2 EMT in vitro,the evidences for and against type 2 EMT in vivo and discuss the heterogeneity and pitfalls of the techniques used to detect EMT during fibrotic diseases.We suggest that in order to ascertain the existence of type 2 EMT in vivo,different proper phenotype markers of epithelial and mesenchymal cells should be jointly used and cell lineage tracking techniques should be standardized and avoid false positives.Finally,we believe that if EMT really occurs and contributes to tissue fibrosis,efforts should be made to block or reverse EMTto attenuate fibrotic process.关键词
epithelial mesenchymal transition/tissue fibrosis/fibroblastKey words
epithelial mesenchymal transition/tissue fibrosis/fibroblast引用本文复制引用
XU Xue-feng,DAI Hua-ping..Type 2 epithelial mesenchymal transition in vivo: truth or pitfalls?[J].中华医学杂志（英文版）,2012,125(18):3312-3317,6.基金项目
This work was supported by grants from the National Natural Science Foundation of China (No.30971312),Beijing Natural Science Foundation (No.7102059) and the Key Project of Beijing Municipal Education Commission Sci-Tech Development Program (No.KZ201110025026). （No.30971312）
