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Proper development of organs leads to cells segregation. In many tissues, ephrins are present in one cell population and Eph receptors in the other.
When these cells come into contact, ephrins bind to their receptors, triggering signalling inside both cells that stops them from mixing.
When cells of different types contacted each other, they rebounded in opposite directions, this repulsion is the main force separating the cell types to form different borders.
In a normal condition, N-cadherin suppresses repulsion between ‘like’ cells. This suppression is vital for ‘like’ cells to stick together, and to prevent them from invading ‘non-like’ cells enabling a sharp border to form between different cell.
Ephrins and their receptors work to keep cells in the right places, and the critical role of N-cadherin to keep like-cells together. But cancer cells cross borders and spread through the body.
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