and necrosis are two major
ways by which cells die. Apoptosis is the ordered disassembly of
the cell from within. It's a natural mechanism by which cells "commit suicide" when
they have outlived their purpose, become defective, or have
... The old or defective cells "take
one for the team." That some cells die and other live on to
replicate helps to achieve a balance in the body.
What happens in a cancer cell is that some parts of the cell machinery
that carry out, signal for, or authorize apoptosis no longer function
... because of damage to genes that produce proteins that regulate or
carry out these functions.
So the search has been on to identify how cancer cells resist cell death
and then to design a drug that inhibits this mechanism. This class
of drugs is sometimes called inhibitors of the inhibitors of
apoptosis - agents that allows the "red KILL button" to be pressed.
you've seen a movie with apoptosis as part of the plot ... in almost
any James Bond film. A fortress containing classified
information is rigged for destruction by the owners if the security of
the building is compromised. The process requiring a series of
commands, which are relayed from one authorized person to another.
This to prevent a programmed self-destruction by a careless mistake or
a rouge individual. The fail-safe system is carried out from within by specialists, and
regulated by others.
... The trigger is not pulled until all the criteria
is met: the security threat is real and it can't be corrected; the
command has been given by authorized individuals and verified by
others, and the actions carried out by specialized personnel.
The security breach starts a chain of events (a cascade); each player
communicating to the other until the big red button is pushed and the
building destroyed; the sensitive information within it evaporating.
Similarly, our cells are rigged for self destruction.
Many chemotherapy treatments are designed to exploit apoptosis ... by
causing sufficient damage to the cells that force the issue,
magnifying the urgency to self-destruct. Waking up the components in
the cell that authorize apoptosis, such as the P53 gene.
Imagine that a key protein within the cell is overactive and is giving
a STOP order. Then imagine a small molecule drug that fits the shape
of this protein, stopping the STOP order.
for a video explanation of apoptosis by Cancerquest.org: