Cadherins (named for 'calcium-dependent adhesion') are a type of cell adhesion molecule (CAM) that is important in the formation of adherens junctions to bind cells with each other. Cadherins are dependent on calcium to function. Cell-cell adhesion is mediated by extracellular cadherin domains. Cadherins behave as both receptors and ligands for other molecules. During development, their behavior assists in properly positioning cells: they are responsible for the separation of the different tissue layers, and for cellular migration. Many cadherins are specified for specific functions in the cell, and they are differentially expressed in a developing embryo. It is a tumor suppressor gene. Besides its role in normal cells, this highly conserved gene can play a major role in malignant cell transformation, and especially in tumor development and progression. The suppression of E-cadherin expression is regarded as one of the main molecular events responsible for dysfunction in cell-cell adhesion.