Download Cancer

Cancer

Normal cells have regulation that keeps
their rates of cell division in check.

Normal cells generally remain in one
location

Cancer is unregulated growth of a cell
population
Bio 130 Human Biology
Characteristics of Benign
Tumors and Cancers
Bio 130 Human Biology
Table 18.1
Terms





Hyperplasia – increased formation
Tumor – new growth
Benign tumors- have defined
characteristics
Dysplasia- cells change form
Cancer- at least some cells loose
organization.
Bio 130 Human Biology
Tumors

Benign:




Remain in one location
Single, well-defined mass
May be surrounded by connective tissue
Cancerous:



Abnormal cell structure, may appear undifferentiated
May spread
Edge of tumor not clearly defined
Bio 130 Human Biology
Malignant Tumor
Development
Bio 130 Human Biology
Figure 18.2
How cancers develop





Is genetic in character
Proto-oncogenes
Oncogenes
Tumor suppressor genes
p53
Bio 130 Human Biology
How Cancer Develops

Mutated or damaged genes



Proto-oncogenes: normal regulatory genes
Oncogenes: mutated or damaged proto-oncogenes
Tumor suppressor genes: regulatory genes repress cell
growth, division, differentiation, adhesion


May be turned off, damaged, or mutated in cancers
Mutator genes: genes of DNA repair, when they are
damages the cell is more likely to make a mistake.
Bio 130 Human Biology
Indicated cause of cancer




Carcinogens
Inherited susceptibility
Viruses and bacteria
Starts with a single cell that is no longer
under normal control
Bio 130 Human Biology
Cancer Characteristics





loss of contact inhibition
Cancer cells do not self-destruct when
their DNA is damaged
Cancer cells divide indefinitely
Cancer cells attract a blood supply
Cancer cells do not adhere to neighboring
cells
Bio 130 Human Biology
The immune system plays an
important role

If your immune system recognizes a cell
as being cancerous then it will be
destroyed
Bio 130 Human Biology
Progredssion of
cancer requires
multiple genetic
changes in
regulatory genes.
Bio 130 Human Biology
Testing for Cancer

Tumor Imagine




PET and MRI focus on
metabolic differences
Ethaical problems
withgenetic testing?
Large scale testing.
X rays
Positron emis
temography
Magnetic resonance
imaging

Genetic testing


Enzyme markers

Bio 130 Human Biology
Cancer Treatments





Conventional treatments: surgery, radiation, and
chemotherapy
Delivery mechanisms: coated metal beads, lightsensitive drugs
Immunotherapy: promotes the immune response
Starving cancers: inhibits angiogenesis
Molecular treatments: target oncogenes
Bio 130 Human Biology
Treatment of cancer





Surgery
Radiation
Chemotherapy
Immunotherapy
Inhibiting angiogenesis
Bio 130 Human Biology
Surgery, Radiation, and
Chemotherapy Are Conventional
Ways to Treat Cancer






Surgery is used to remove tumors
Radiation therapy is used to kill localized cancer cells
Chemotherapy is used to kill cancer cells throughout the
body
Immunotherapy boosts the immune responses against
cancer cells
Inhibition of blood vessel formation may slow the spread
of cancer cells
Gene therapy may someday help fight cancer in several
ways
Bio 130 Human Biology
Some common cancers





Skin
Breast
Prostate
Lung
Colon rectum
Bio 130 Human Biology
Ten Most Common Cancers
Bio 130 Human Biology
Table 18.3
Prevention

Best way to beat cancer is to not get it.
Bio 130 Human Biology
Most Cancers Are Preventable








Know family history
Get regular medical screenings
Learn self-examination techniques
Avoid direct sunlight 10 a.m. to 4 p.m., avoid
sunlamps and tanning salons
Watch diet and weight
Don’t smoke
Drink in moderation, if at all
Be informed
Bio 130 Human Biology