2. Index
-Introduction.
-The characteristics of cancer.
-Cancer is genetic disease.
-Types of cancer genes.
-What causes cancer?
-Carcinogens.
-Benign and malignant.
-Cancer treatment and prevention.
3. Introduction of cancer
The division of normal cells is precisely
controlled. New cells are only formed for
growth or to replace dead ones.
Cancerous cells divide repeatedly out of
control even though they are not needed,
they crowd out other normal cells and
function abnormally. They can also
destroy the correct functioning of major
organs.
4. The Characteristics of Cance
As genes switch on and off, they
determine when and how fast the cell will
grow and divide, when it will stop
dividing, and even when it will die.
Cancer can result when controls over cell
division are lost…
5. Cancer is a Genetic Diseas
Cancer is a genetic disease that develops
in a predictable sequence of steps..
Carcinogenesis
• Transformation of a normal cell
into a cancerous cell.
• Step-by-step transformation.
7. A Common Type of Colorectal
Cancer May Develop by These
Steps
8.
9. Types of cancer genes
Type of gene Normal function Mutated function Types of proteins
Promotes
Oncogene Promotes division - Growth factors
division abnormal time
or cell type
Tumor
Suppresses Fails to Checkpoint
suppressor
cell division suppress molecules
gene
division
DNA repair Enzymes for
Repair DNA Fail to repair
gene mismatch or
mutations DNA mutations
mutation excision repair
10. What causes cancer?
Cancer arises from the mutation of a
normal gene.
Mutated genes that cause cancer are
called oncogenes.
It is thought that several mutations need
to occur to give rise to cancer.
Cells that are old or not functioning
properly normally self destruct and are
replaced by new cells.
However, cancerous cells do not self
destruct and continue to divide rapidly
producing millions of new cancerous cells.
11. A factor which brings about a mutation is
called a mutagen.
A mutagen is mutagenic.
Any agent that causes cancer is called a
carcinogen and is described as
carcinogenic.
So some mutagens are carcinogenic…
12. carcinogens
-Ionising radiation – X Rays, UV light.
-Chemicals – tar from cigarettes.
-Virus infection – papilloma virus can be
responsible for cervical cancer.
-Hereditary predisposition – Some
families are more susceptible to getting
certain cancers.
13. Other Factors Also May Lead to Canc
Breakdowns in immunity
Healthy immune system can target
and destroy cancer cells.
When cancer cells have altered
proteins at its surface, cells are not
destroyed.
Risk of cancer increases:
-With age.
-When an immune system has
been suppressed for a long time.
-HIV infection.
-Immunosuppressant drugs.
-Anxiety and depression.
14. Benign and malignant?
Benign tumours do not spread from their
site of origin, but can crowd out (squash)
surrounding cells eg brain tumour, warts.
Malignant tumours can spread from the
original site and cause secondary
tumours. This is called metastasis. They
interfere with neighbouring cells and can
block blood vessels, the gut, glands, lungs
etc.
Both types of tumour can tire the body
out as they both need a huge amount of
nutrients to sustain the rapid growth and
division of the cells.
17. Some Major Types of Cance
In general, a cancer is named according to the
type of tissue in which it first forms
Sarcomas: cancer of connective tissue
Carcinomas: cancer arising from
epithelium
Lymphomas: cancer of lymphoid tissue
Leukemias: cancer of stem cells
Gliomas: cancer of brain glial cells
18. Cancer Treatment and Preventio
When a person is diagnosed with cancer, a
variety of weapons are available to
combat it:
Chemotherapy drugs
Radiation therapy
Surgery
And other….
19. Chemotherapy
Drugs used to kill cancer cells; disrupt some
aspect of cell division.
Toxic to healthy cells; hair, bone marrow,
lymphocytes, and epithelial cells of intestinal
lining .
Side effects include hair loss, nausea, vomiting,
and reduced immune responses.
20. Radiation therapy
In radiotherapy, high-energy rays are used
to kill cancer cells and stop them from
growing and dividing. Like surgery,
radiotherapy is a local treatment; it can
affect cancer cells only in the treated area.
Radiotherapy is usually given on an
outpatient basis, 5 days a week, for
several weeks. Patients are not
radioactive during or after treatment.
21. The most common side effects are
tiredness, skin reactions such as rash or
redness, and loss of appetite. Radiation
therapy may also cause a temporary
lowering of the white blood cell count,
cells that help protect the body against
infection. The side effects are usually
temporary, developing gradually over the
weeks of the treatment, and improving
gradually after treatment is completed.
22. Surgery therapy
Surgery is the primary method of
treatment of most isolated solid cancers
and may play a role in palliation and
prolongation of survival. It is typically an
important part of making the definitive
diagnosis and staging the tumor as
biopsies are usually required. In localized
cancer surgery typically attempts to
remove the entire mass along with, in
certain cases, the lymph nodes in the
area. For some types of cancer this is all
that is needed for a good outcome.
23. Hormone therapy
Some types of cancer, for example, breast
cancer and prostate cancer, depend on
hormones to grow. For this reason,
doctors may recommend therapy that
prevents cancer cells from getting or using
the hormones they need. Sometimes, the
patient has surgery to remove the organs
(like the ovaries or testes) that make the
hormones. Or drugs are used to stop
hormone production or change the way
the hormones work.
24. Hormone therapy may cause nausea,
swelling of the limbs or weight gain
through water retention. In women, there
may be irregular periods and vaginal
dryness. In men, there may be impotence
or loss of sexual desire.
25. Biological Therapy
Biological therapy, also called
immunotherapy, uses the body's own
immune system to fight infection and
disease or protect the body from some of
the side effects of other forms of
treatment. Monoclonal antibodies,
interferon, interleukin-2, and colony-
stimulating factors such as GM-CSF and G-
CSF, are forms of biological therapy.
26. These treatments often cause temporary
flu-like symptoms such as fever and chills,
muscle aches and weakness, loss of
appetite and diarrhoea.
27. Good Lifestyle Choices Can Limit
Cancer Risk
-Avoid tobacco completely.
-Maintain a desirable weight; eat a low-fat
diet with plenty of fruits and vegetables.
-Avoid alcohol .
-Make sure your living and work
environment is safe from carcinogens.
-Protect your skin from the sun’s UV rays.
28. finally
. Remember you can’t inherit
cancer its just that you maybe
more susceptible to getting it. so
be careful and prevent your
self…….