The concept of epithelial-mesenchymal transitions (EMT) has brought valuable insights to the study of complex processes involved in early embryo development, wound healing, carcinoma progression or kidney fibrosis. Major advances are reported in identifying new model systems, transcriptional regulators (including chromatin structure and microRNA), specific signaling pathways, and effector molecules.  In this special issue, recent developments in the EMT field are reviewed, including the first localizations of Snail proteins in human cancers. Snail signaling and targets are carefully explored in several systems. Another emerging signaling pathway discussed involves TGF-beta. Several new concepts are consolidated including partial EMT, resulting in a metastable phenotype in cancer systems, and reversed EMT, described during bladder cancer progression as a mesenchymal-epithelial transition. Some of the papers focus on the first therapeutic approaches and different microarray analysis approaches specifically targeting the EMT process.  Basic and clinical reseachers, clinicians as well as graduate and PhD students in the fields of cell and developmental biology, oncology and nephrology will appreciate this multidisciplinary and up-to-date overview of the EMT process.

Table of Contents:
Epithelial-Mesenchymal Transitions - New Insights into Signaling, Development and Pathogenesis: Thompson, E.W. et al.; Mesenchymal to Epithelial Transition in Development and Disease: Chaffer, C.L. et al.; A Human Three-Dimensional Cell Line Model Allows the Study of Dynamic and Reversible Epithelial-Mesenchymal and Mesenchymal-Epithelial Transition That Underpins Colorectal Carcinogenesis: Vincan, E. et al.; Epithelial-Mesenchymal Transition and Colon Cancer: Gaining Insights into Tumor Progression Using LIM 1863 Cells: Bates, R.C. et al.; Signal Transduction Pathways Involved in Epithelial-Mesenchymal Transition in Oral Cancer Compared with Other Cancers: Chang, J.Y.F. et al.; Epithelial-Mesenchymal Transition in Rhesus Monkey Embryonic Stem Cell Colonies: A Model for Processes Involved in Gastrulation?: Denker, H.-W. et al.; [beta]-Catenin/LEF-1 Signalling in Breast Cancer - Central Players Activated by a Plethora of Inputs: Gebeshuber, C.A. et al.; [beta]-Catenin and ZO-1: Shuttle Molecules Involved in Tumor Invasion-Associated Epithelial-Mesenchymal Transition Processes: Polette, M. et al.; Nuclear Localization Signals of the E-Cadherin Transcriptional Repressor Snail: Ko, H.S. et al.; Role of Glycogen Synthase Kinase-3 in Cell Fate and Epithelial-Mesenchymal Transitions: Doble, B.W.; Woodgett, J.R.; Epithelial-Mesenchymal Transition in Ovarian Cancer Progression: A Crucial Role for the Endothelin Axis: Bagnato, A.; Rosano, L.; CCN6 (WISP3) as a New Regulator of the Epithelial Phenotype in Breast Cancer: Kleer, C.G. et al.; Rho Proteins and Cell-Matrix Interactions in Cancer: Wu, M. et al.; Matrix Metalloproteinase-Induced Malignancy in Mammary Epithelial Cells: Stallings-Mann, M.; Radisky, D.; Epithelial-Mesenchymal Transition in Prostate Cancer and the Potential Role of Kallikrein Serine Proteases: Lawrence, M.G. et al.; Regulation of Extracellular Matrix Remodeling following Transforming Growth Factor-[beta]1/Epidermal Growth Factor-Stimulated Epithelial-Mesenchymal Transition in Human Premalignant Keratinocytes: Wilkins-Port, C.E.; Higgins, P.J.; Smad4-Independent TGF-[beta] Signaling in Tumor Cell Migration: Giehl, K. et al.; Complexity in Interpretation of Embryonic Epithelial-Mesenchymal Transformation in Response to Transforming Growth Factor-[beta] Signaling: Ahmed, S.; Nawshad, A.; Multiple Transforming Growth Factor-[beta] Isoforms and Receptors Function during Epithelial-Mesenchymal Cell Transformation in the Embryonic Heart: Mercado-Pimentel, M.E.; Runyan, R.B.; Transforming Growth Factor-[beta] and microRNA:mRNA Regulatory Networks in Epithelial Plasticity: Zavadil, J. et al.; Chromatin Structure Regulation in Transforming Growth Factor-[beta]-Directed Epithelial-Mesenchymal Transition: Blumenberg, M. et al.; Posttranslational Truncation of E-Cadherin and Significance for Tumour Progression: Masterson, J.; O'Dea, S.; Signaling Pathways Involved in Collagen-Induced Disruption of the E-Cadherin Complex during Epithelial-Mesenchymal Transition: Imamichi, Y.; Menke, A.; Vimentin and Epithelial-Mesenchymal Transition in Human Breast Cancer - Observations in vitro and in vivo: Kokkinos, M.I. et al.; Analysis of the E-Cadherin Repressor Snail in Primary Human Cancers: Becker, K.-F. et al.; Liver Fibrosis: Possible Involvement of EMT: Ikegami, T. et al.; The Role of Tubular Epithelial-Mesenchymal Transition in Progressive Kidney Disease: Burns, W.C. et al.; PRL-3: A Metastasis-Associated Phosphatase in Search of a Function: Bessette, D.C. et al.; A Protein-Permeable Scaffold of a Collagen Vitrigel Membrane Useful for Reconstructing Crosstalk Models between Two Different Cell Types: Takezawa, T. et al.