Contact inhibition

Contact inhibition is the natural process of arresting cell growth when two or more cells come into contact with each other. Oncologists use this property to distinguish between normal and cancerous cells.

Cell lines used widely in animal cell culture laboratories are genetically modified to suppress apoptosis however maintain this phenomenon. Therefore, cells are cancerous however their proliferation could be controlled when present in low serum levels or when in contact with neighbouring cells (i.e. contact inhibition).

In tissue culture laboratories cells growing on T25 and T75 flasks need constant replacements to maintain their normal cell numbers otherwise cells would display contact inhibition and therefore, die as a result.

Cancerous cells typically lose this property and thus grow in an uncontrolled manner even when in contact with neighbouring cells. Cells of naked mole rats, a species in which cancer has never been observed, show hypersensitivity to contact inhibition.