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What is cancer? How do people know they have cancer?
How do tumors develop and cancer spread?
Why are older people more likely to get cancer?
What regulations do cells have that help prevent cancer?
What are some of the causes of cancer?
How can one’s environment affect their chances of getting cancer?
How Can Chemicals Cause Cancer?
How can viruses cause cancer?
Why does one family have a history of cancer?
What can you and your body do to help prevent getting cancer?
What can you eat to help prevent you from getting cancer? Why do these
foods help?
How can my body fight cancer?
How common is cancer?
What are some of the common treatments for cancer and how do they
work?
What is cancer?
How do people find out if they have cancer?
Cancer Simplified
Cells that have gone awry, because the genes that help
cells “follow the rules” have mutated. Thus they can
divide rapidly, start acting like other cells and move from
where they are supposed to stay.
How do tumors develop
and cancer spread?
http://science.education.nih.gov/supplements/Supplements
Corrections.nsf/Movies/Cancer_Movies.htm
Differences between normal and
cancerous cell
Why are older people more likely to
get cancer?
Cancer develops step-by-step, across time, as an
accumulation of many molecular changes, each
contributing some of the characteristics that
eventually produce cancer cells.
What regulations do cells
have that help prevent
Cancer?
Cell Cycle
Can anyone think of an Analogy
for the Cell Cycle?
Cells maintain strict
control over Cell
Division
We have genes in our DNA called
tumor suppressor genes that code
for proteins that interact with the
molecules cyclin and CDK which
are controlling the cell cycle at
certain checkpoints to determine if
the DNA is good enough shape to
proceed to division. If the DNA is
damaged in anyway it is either
repaired or the cell undergoes
programmed cell death.
DNA can only replicate once
with each cell divison.
A cell with to much DNA material
does not behave correctly so DNA
must only replicate once with each
cycle and each daughter cell must
have the correct amount of genetic
material.
DNA Damage must be
repaired before
replication.
To prevent a cell from having the
ability to become cancerous,
damage must be repaired.
If a cell fails to pass a checkpoint…
It will undergo programmed cell death, also known as apoptosis.
This prevents damaged cells from dividing and leading to
cancerous cells.
Class Demo
What are some causes of cancer?
environment (ex: sun), chemicals, infection, genes, toxins etc.
Cancer has multiple causes
-mutated tumor suppressor genes
-mutated cell cycle regulators
-mutated repair proteins
-mutated receptor signaling
constant division, etc.
How can one’s environment affect
their chances of getting cancer?
Example: UVA and UVB light exposure
By damaging the skin’s cellular DNA, excessive UV
radiation produces genetic mutations that can lead to skin
cancer.
How Can Chemicals Cause
Cancer?
By causing DNA Damage
• Chemicals can cause mutations in DNA
such as missense and nonsense.
• They can cause the bases to stick
together in a process called dimerization.
• Various chemical modifications.
• Cancer causing chemicals are known as
carcinogens.
How can viruses cause cancer?
Think about it!
Viruses insert their own DNA into
our cells so our cells will make
more viruses. The viral genes that
cause cancer activate or over
express similar human genes that
cause the cells to exhibit
uncontrolled cell divison.
Cell communication gone awry
• One way viruses have been found to
cause cancer is through mutated receptors
on the cell surface. What might the
receptor be for?
Why does one family have a
history of cancer?
Heredity-This is the process by which an offspring cell or organism
acquires or becomes predisposed to the characteristics of its parent
cell or organism.
Xeroderma pigmentosum
Autosomal recessive disorder caused by mutations in
genes that code for DNA repair proteins
Retinoblastoma and RB1
Retinoblastoma is a form of cancer that young children
usually get because of one mutated copy of a protein called
RB1. What must happen for retinoblastoma to occur?
Remember we have two copies
of a gene.
• With only one good copy of the gene, all it
takes is one hit on that gene for the stage
to be set for retinoblastoma to occur.
Game Time!
Game
What can you and your body do to
help prevent getting cancer?
Don’t Smoke!
What can I eat to help prevent me
from getting cancer?
Why do these foods help prevent
cancer?
ANTIOXIDANTS
Antioxidants are substances that may protect your
cells against the effects of free radicals. Free
radicals can damage cells, and may play a role in
heart disease, cancer and other diseases.
How can my body fight cancer?
The Immune System
The Immune System
The Immune System
The Immune System
Statistics
How common is cancer?
• Approximately 6 of 10 people in will have children
– 2,3,5,6 stand
• Approximately 3 in 10 of the people in the room will be
involved in an alcohol-related automobile accident
sometime in their lifetimes.
– 3 and 6 stand
• Approximately 1 in 3 (or in this case, 2 in 6) of the people
in the room will develop cancer sometime during their
lifetimes.
– 1 and 4 stand
• Approximately 25 % of the U.S. population who will die
of cancer.
– ¼ of people standing should sit
What are some of the common treatments
for cancer?
How does biological therapy work?
It uses the body's immune system, either directly or
indirectly, to fight cancer or to lessen the side effects that
may be caused by some cancer treatments.
How does surgery help?
Surgery may be used for cancer prevention to remove
tissue before cancer develops, diagnosis to determine if
tumor is cancerous or not, staging to see how advanced
the cancer is, and primary treatment to remove
cancerous tumors.
How does chemotherapy work?
It uses drugs to destroy cancer cells, stop cancer cells
from spreading, and slow the growth of cancer cells. It
can be given through an IV, a shot into part of the body,
a pill or liquid to swallow, or a cream to rub on skin.
How does radiation work?
It uses high powered x-rays or radioactive seeds
to damage the DNA and kill cancer cells. Other
rapidly growing cells may also be damaged in
the process.