Transcript Skin Cancer - Life Science Academy

Medical Interventions
Unit 3 Review
Lesson 3.1 Detecting Cancer
Activity 3.1.1 Who is Affected by Cancer?
Activity 3.1.2 Diagnostic Imaging Career Activity
Activity 3.1.3 When Cells Lose Control
Activity 3.1.4 DNA Microarray
Activity 3.1.5 Unlocking the Secrets in Our Genes (math activity)
Lesson 3.2 Reducing Cancer Risk
Activity 3.2.1 Am I at Risk?
Activity 3.2.2 Skin Cancer Prevention
Activity 3.2.3 Breast Cancer Screening and Prevention
Activity 3.2.4 Virology Career Activity
Activity 3.2.5 Routine Screenings
Lesson 3.3 Treating Cancer
Activity 3.3.1 Diary of a Cancer Patient
Project 3.3.2 Biofeedback Therapy
Project 3.3.3 Design of a Prosthetic Arm
Project 3.3.4 Occupational and Physical Therapy Careers
Lesson 3.1 Detecting Cancer
Activity 3.1.1 Who is Affected by Cancer?
Activity 3.1.2 Diagnostic Imaging Career Activity
Activity 3.1.3 When Cells Lose Control
Activity 3.1.4 DNA Microarray
Activity 3.1.5 Unlocking the Secrets in Our Genes
What fundamental characteristics do all
cancers have in common?
• Genetic component
• Environmental component – Smoking, radiation, diet/health
• If caught early and removed before it spreads the cancer may
not cause problems
• If it spreads/metastasizes there could be potential problems
• Incidence of cancer increases with age
• Cancer can affect any organ or tissue in the body
What fundamental characteristics do all
cancers have in common?
• Proto-oncogenes – Normally control cell division by telling the
cell to divide. Cancer can be caused by these genes being
turned on too much
– Mutation can cause them to be oncogenes, which lead to
uncontrolled division
– Translocation of a promoter can cause the oncogenes to be
turned on more than they are supposed to be
– A mutation can cause multiple proto-oncogenes, which will
cause it to be overexpressed and uncontrolled cell division
What fundamental characteristics do all
cancers have in common?
• Tumor-Suppressor Genes– Normally control cell division by
telling the cell to stop dividing. Cancer can be caused by
these genes being turned off
• Example is the p53 gene
– Triggers apoptosis (programmed cell death) if there is a
mutation
– Activates DNA repair enzymes to repair any mutations
– Halts the cell cycle so no copies of the cell are made with
the mutation
• Mutations in these genes can lead to cancer
What fundamental characteristics do all
cancers have in common?
• Cancer cells can proliferate indefinitely in culture.
• Cancer cells do not exhibit contact inhibition. Once cancer cells
cover the surface of the dish, the cells will continue dividing and
pile up on top of each other.
• Cancer cells undergo morphological changes and will exhibit
various shapes.
• Cancer cells can grow under less stringent conditions, and can
usually grow on simple culture medium.
• Cancer cells often have an abnormal number of chromosomes
and the chromosomes often have an abnormal structure.
In what ways are diagnostic imaging
technologies used to diagnose and treat
disorders?
• X-Ray – uses radiation to view broken bones bones, lung
diseases, and digestive system
• CT scan – uses multiple X-rays in a tube to produce crosssectional views of bone and soft tissue, like organs.
• MRI – uses magnets to produce detailed cross-sectional views of
soft body tissue to identify diseases.
• Bone Scan – Add radioactive tracers that are soaked up by the
bone to produce full skeletal view to identify abnormal bone
growth
What do DNA microarrays measure?
• DNA microarrays measure the number and amount of genes
turned on and off in cancer cells vs. normal cells
• We can do this by collecting mRNA from the cells, which will
only be made if the genes are turned on
• We can also determine if there is a correlation between genes
interacting with each other
How is DNA microarray technology used to
determine the differences in gene expression
between different tissue samples?
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Red – The genes are only on in cancer cells
Yellow – The genes are on in cancer and normal cells
Black – The genes are not on in either cells
Green – The genes are only on in normal cells
How is DNA microarray technology used to
determine the differences in gene expression
between different tissue samples?
• Microarrays can also tell us the relative intensity of the gene
expression because there will be varying shades of the colors.
• The bright red would be a high expression of the gene in cancer
cells, where as the dark red would be a low expression.
• The same would be true for the yellow and the green
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How is DNA microarray technology used to determine
the differences in gene expression between different
We can superimpose
tissue samples?
the colors from the
cancer gene and the
normal gene over each
other to get one single
color.
We assign this color a
number (ratio)
A number over 1 the
gene is expressed more
in cancer cells
A number under 1 the
gene is less expressed in
cancer cells
A number equal to 1 the
gene is expressed the
same in both cells
0 means the gene is not
expressed in either cell
How are the similarities of gene expression patterns
between different individuals calculated?
• Using statistical analyses we look at gene expression of several
genes in several patients that have the same disease.
• We use correlation coefficients to determine if there is a
pattern between what genes are turned on and what genes
are turned off
• If there is a positive correlation then both of the genes are
behaving in the same way
• If there is a negative correlation then the genes are behaving
in opposite ways (one is on and the other is off)
• Correlation of 1 means that gene expression is identical
• Correlation of 0 means there is no correlation
• A number further from 0 and closer to 1 means that there is a
stronger correlation
REVIEW ACTIVITY 3.1.5 (MATH ACTIVITY)
Lesson 3.2 Reducing Cancer Risk
Activity 3.2.1 Am I at Risk?
Activity 3.2.2 Skin Cancer Prevention
Activity 3.2.3 Breast Cancer Screening and Prevention
Activity 3.2.4 Virology Career Activity
Activity 3.2.5 Routine Screenings
In what ways do different risk factors increase the
chance that a person will develop cancer? How can
lifestyle changes reduce the risk for developing cancer?
• Biological
– Age – the risk for all cancers increase
– Infections – Some viral and bacterial infections can cause an
increase risk of cancer
– Reduce these risks by being screened often and getting
vaccinations
• Genetic
– Sometimes a gene can be inherited from parents that
increases the risk of cancer, because you already one step
(mutation) towards cancer.
– Hereditary cancer and familial cancer would be genetic.
Sporadic cancer (most cancers) are not genetic.
In what ways do different risk factors increase the
chance that a person will develop cancer? How can
lifestyle changes reduce the risk for developing cancer?
• Environmental
– Pollution – Smoke and chemicals, like asbestos, can damage
DNA
– UV Radiation - More on this later
– Radiation – Excessive radiation from sources, like Xrays
• Behavioral
– Red meat and other foods have been shown to increase risks
of cancer (other foods, like antioxidants have been shown to
lower cancer)
– Smoking increases risk of lung cancer (same with smokeless
tobacco and mouth cancer)
– Not taking preventative measures, like staying out of the sun
Skin Cancer
• Types
– Basal/Squamous – most common and least dangerous form
that can be found anywhere on the body
– Melonoma – most common on face, chest, and legs, and are
more likely to metastize
• ABCDE
– Asymmetry
– Border irregularity
– Color changes
– Diameter greater than 1/4 inch
– Evolving
Skin Cancer
Skin Cancer
Treatment
– pyrimidine antagonists
(5-Fluorouracil or 5-FU)
inhibit the enzyme that
makes pyrimidines
(thymine, uracil, cytosine),
which stops production of
DNA and RNA.
– While this works in some
patients it has a variety of
side effects including
burning and sun sensitivity
How can molecular tests be used to detect inherited
genetic mutations associated with certain cancers?
Genetic Marker Analysis – Easier and cheaper genetic analysis than
DNA Sequencing.
– Markers are located directly in front of the gene in question
(therefore, often passed on with the gene)
– Markers are Short Tandem Repeats (non-coding DNA that are
repetitive sequences of DNA)
• STRs are highly variable by length (sequence can repeat any
number of times making them different lengths)
• Easy to identify STRs using gel electrophoresis because they
are simply different lengths
How can molecular tests be used to detect inherited
genetic mutations associated with certain cancers?
Genetic markers used in conjunction with pedigrees
1. Identify people with gene for cancer
2. Conduct a marker analysis on family members and unknown
family member using gel electrophoresis
3. Identify STR sizes using standard curve
4. Compare STRs and identify alleles possessed by each family
member
5. Analyze allele to see if there is a correlation between alleles
and family members with cancer
Breast Cancer
Genetic Component
– BRCA 1 and BRCA 2 are tumor suppressor genes
– Mutations in these may lead to tumors
– 5-10% of breast cancers are related to these genes
– BRCA 2 genes are linked to male breast cancer
Preventative measures
– Prophylactic mastectomy – reduces breast cancer risk by 90%
– Get it test positive for BRCA 1 or 2 genes, calcium deposits,
radiation therapy, or previous breast cancer
– Hormonal therapy – medicines or removal of the ovaries in
order to reduce estrogen
– Nutrition
– Physical Activity
How can viruses lead to cancer?
• Viruses can cause cancer by injecting DNA into cells and
thereby causing a mutation
• HPV – linked strongly to cervical cancer, vaccines may help, but
will not guard against every strain
• EBV – may lead to lymphomas
• Hepatitis B – Vaccine
• Hepatitis C – No vaccine both may lead to liver cancer
Human Papilloma Viruses (HPVs)
• HPV is a sexually transmitted infection
• HPV causes abnormal cells to start growing and
eventually can turn into cancer cells
• HPV is the main cause of cervical cancer
• HPS is linked to mouth and throat cancer
• There is a vaccine available that protects against 4
types of the HPV virus.
Epstein-Barr Virus (EBV)
• EBV is a type of herpes virus known for causing infectious
mononucleosis (commonly known as “mono”)
• EBV infects and stays in B lymphocytes
• EBV infection increases a person’s risk of developing
nasopharyngeal cancer and Burkitt lymphoma
• EBV is also linked to Hodgkin diseases and stomach
cancer
• No vaccine or medications are available
Hepatitis B Virus (HBV) and
Hepatitis C Virus (HCV)
• Both viruses are known to cause liver infection
• The long-term infection caused by these viruses
increases a person’s chance of developing liver cancer
• There is a vaccine available to prevent HBV infection
• There are a few medications available that are effective
in treating HBV and HCV infections
What is the importance of routine
cancer screenings?
• You should get routine screenings for:
– Prostate
– Colon
– Cervical
– Breast
– Skin, Testicular, and lung
• Early detection of cancers is crucial to stop the
metastases process before the cancer spreads and cause
problems elsewhere.
• It is easier to treat and cure cancer when caught early
Lesson 3.3 Treating Cancer
Activity 3.3.1 Diary of a Cancer Patient
Project 3.3.2 Biofeedback Therapy
Project 3.3.3 Design of a Prosthetic Arm
Project 3.3.4 Occupational and Physical Therapy Careers
What can a cancer patient receiving chemotherapy
and/or radiation therapy expect during treatment?
• Chemotherapy is the use of drugs to kill, prevent the
spreading, slow growth, and treat symptoms of cancer.
• The side effects are different for everyone, but typical
side effects are hair loss, anemia and symptoms that
occur with anemia, increased infections, bleeding, and
bruising, and nausea
• Most of these symptoms are due to the fact that chemo
affects fast growing cells, like blood forming cells in the
bone marrow. Therefore, not as much blood is being
formed.
What can a cancer patient receiving chemotherapy
and/or radiation therapy expect during treatment?
• Radiation is more of local treatment that focuses
radiation onto cancer cells to destroy DNA, causing cells
to stop dividing.
• Radiation can be given externally or internally through
an implant
• Most side effects are localized skin and hair changes
along with fatigue
• This may lead to anger, depression, and helplessness
How is biofeedback therapy used to help patients
improve their health or manage pain?
• Biofeedback changes the mental state of the patient,
which allows them to calm down.
• The patient learns to use their mind to control
involuntary actions of the body, like heart rate, muscle
tension, and respiration rate.
• They can overcome pain by relaxing specific muscle
groups to relieve certain chronic pain and migraines
• This can also help lower blood pressure, anxiety
attacks, asthma attacks, or urination problems
In what ways do artificial limbs allow patients who
suffered the loss of a limb regain lost function?
• Other limbs can offer simple movements, like hooks or
pinchers to allow the person to pick objects up
• Prosthetics can be hooked to other functional parts of
the body that are used to move the prosthetic.
• A patient can use switches and toggles to control the
prosthetic
• Myoelectrics can you muscle impulses to control the
movement of the prosthetic.
How do advances in technology allow for the
development of artificial limbs that look and
move like actual human limbs?
• Special dyes can be used to make the prosthetic the
same color, with freckles, fingerprints and a life like
appearance
• Myoelectrics can use muscle contractions and EMG
signals to control the prosthetic
• Current research is ongoing into the use of brain signals
connected to the motor cortex to move robotic arms,
which could be the new wave of prosthetics.
How do physical and occupational therapists help
patients with disabilities or patients recovering
from surgery or injury?
• PT focus on range of motion, movement, and ability to regain
proper movement
• OT work with patients to practice normal, routine practices
that they have to do everyday, like driving, cooking, and using
the restroom
• They design appropriate exercises for the patients to practice
the intended movement
• They use electric shock, stretching, and massage therapy to
relax and test muscles
• They assign appropriate tools and rehab equipment for the
patients to use and guide the patient in proper use
END