Cadherins in Tissue Organization

Cadherins, a class of cell adhesion molecules, mediate selective adhesion between cells and thus, play a crucial role in establishing and maintaining tissue structures.

During development, undifferentiated cells express specific cadherins on their surface as they differentiate into distinct tissue types, such as E-cadherins on epithelial cells and N-cadherins on neurons.

Because cadherins generally bind other cadherins of the same type, cells can selectively adhere to each other.

Additionally, cells expressing higher cadherin levels segregate from those with lower levels.

Thus, both quantitative and qualitative specificity of cadherins help sort and organize the cells into tissues.

Conversely, the downregulation of cadherin expression leads to the loss of cell adhesion.

For instance, tumor cells that stop expressing cadherins can detach from neighboring cells and overcome the tissue constraints.

This transition, called epithelial to mesenchymal transition or EMT, is an essential step in the progression of tumor cells to malignant cells.