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 cell culture, cells growing in vessels will generally continue to replicate until they form a continuous monolayer on the vessel surface. In this case, they would be subject to contact inhibition. Thus, cells in culture need to be repeatedly passaged (placed into new vessels at a lower density) to maintain normal growth.
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.
Famous quotes containing the word contact:
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