WEBVTT

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Reproduction of our body’s cells
is normally strictly regulated:

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cells only divide

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when they are prompted to do so.

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And cells that are no longer needed

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die off and make space.

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In cancer cells,
these control mechanisms are compromised.

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They reproduce in an uncontrolled manner

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and form cancerous growths or tumors.

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Cancer cells also acquire properties

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that turn them into malignant cells.

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These enable them to invade
surrounding tissue and blood vessels

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and form growths in other parts of the body
known as “metastases”.

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But what causes cancer?

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All of the body’s cells
have genetic material (a “blueprint”).

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The parts of the blueprint
that are implemented in a cell

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determine its properties.

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When a cell divides,
it duplicates its genetic material

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to pass on to the two daughter cells.

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Errors can creep
into the genetic material at this point.

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Normally
a number of errors need to coincide

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to alter the properties of the cells
to such an extent

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that they become malignant.

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• Most genetic errors occur randomly

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and may accumulate in a single cell.

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So the risk of cancer increases with age.

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• Our lifestyle can increase the risk,

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for example smoking,

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UV radiation from the sun,

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infection with certain viruses.

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Being overweight and a lack of exercise

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can make cancer more likely.

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• Environmental factors may also cause
errors in the genetic material,

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such as radiation or particulate matter.

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• However some genetic changes

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which make cancer more likely

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can also be inherited.

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In short:

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Cancers are caused
by changes in genetic material.

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These changes cause the body’s cells

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to start dividing
in an uncontrolled manner.

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Malignant tumors,

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which can invade surrounding tissue
and blood vessels

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and form metastases,

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are referred to as cancer.