Figure 3.

Schematic illustration of the key events during MMT. Mesothelial to mesenchymal transition (MMT) occurs when mesothelial cells lose their epithelial-like characteristics, including dissolution of cell-cell junctions, that is, tight junctions, adherens junctions and desmosomes, and loss of apical-basolateral polarity, and acquire a mesenchymal phenotype, characterized by actin reorganization and stress fiber formation, migration, and invasion. The diagram shows four key steps essential for the completion of entire MMT, the most commonly used mesothelial and mesenchymal markers, and the molecules and signal transduction pathways that act either as inducer or modulator of the MMT process. See text for details.