HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Choi, J. Articles by Joo, C.-K. Search for Related Content PubMed PubMed Citation Articles by Choi, J. Articles by Joo, C.-K.

Transforming Growth Factor-ß1 Represses E-Cadherin Production via Slug Expression in Lens Epithelial Cells

¹From the Department of Ophthalmology and Visual Science, College of Medicine, and the ³Korean Eye Tissue and Gene Bank, The Catholic University of Korea, Seocho-ku, Seoul, Korea.

PURPOSE. TGFß is a potent candidate for epithelial–mesenchymal transition (EMT) during the development of anterior polar cataracts in the human lens. The Snail superfamily is involved in EMT through the repression of E-cadherin production. This study was conducted to determine whether the Snail gene family is activated in the process of TGFß1-induced EMT and how TGFß1 regulates the expression of this gene family.

METHODS. Total RNA extracted from human cataract samples was subjected to the real-time PCR quantification of Slug mRNA. Induction of Slug expression by TGFß1 (10 ng/mL) in lens epithelial cells was determined by RT-PCR, immunostaining, immunoblot analysis, and Slug promoter analysis. A series of Slug promoter deletion constructs was used to identify the putative regulatory element responsive to TGF signaling. Chromatin immunoprecipitation was performed to determine whether Sp1 associates with the endogenous Slug promoter. Inhibition of Slug expression with Slug siRNA was used to investigate the role of Slug in TGFß-mediated EMT.

RESULTS. Slug levels were highly upregulated in lens epithelial cells obtained from patients with anterior polar cataracts. Treatment of TGFß1 induced the expression of Slug in both lens and other epithelial cells in vitro. TGFß1-induced Slug expression was significantly inhibited by the MEK- and JNK/SAPK-specific inhibitors, but not by transfection with dominant-negative forms of Smads or small GTPase proteins, indicating that MAPK pathways are involved in the regulation of Slug expression by TGFß1. The Slug promoter analysis revealed that the Sp1 binding site in the Slug promoter is responsible for TGFß1-induced Slug expression. In addition, the TGFß1-mediated repression of E-cadherin was significantly inhibited by Slug siRNA.

CONCLUSIONS. These data suggest that TGFß1 induces Slug expression and that the repression of E-cadherin production by TGFß1 is mediated by the induction of Slug in lens epithelial cells.

This article has been cited by other articles:

				D. D. Mruk, B. Silvestrini, and C. Y. Cheng Anchoring Junctions As Drug Targets: Role in Contraceptive Development Pharmacol. Rev., June 1, 2008; 60(2): 146 - 180. [Abstract] [Full Text] [PDF]

				M. Herfs, P. Hubert, N. Kholod, J. H. Caberg, C. Gilles, G. Berx, P. Savagner, J. Boniver, and P. Delvenne Transforming Growth Factor-{beta}1-Mediated Slug and Snail Transcription Factor Up-Regulation Reduces the Density of Langerhans Cells in Epithelial Metaplasia by Affecting E-Cadherin Expression Am. J. Pathol., May 1, 2008; 172(5): 1391 - 1402. [Abstract] [Full Text] [PDF]