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Michael SheetsTopics in Bioengineering Fall 2014
GENETICS OF CANCER
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Doctors noticed a while back (i.e. ancient Greece 5) that some cancers run in families
Could be similar environment – smoking, food, radiation
But appeared to have more to it
INHERITED CANCER?
McPherson et al, 2000.
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Along came the HGP and huge advances in genetics…
Individuals can be tested for related genes
FAMILY CANCER SYNDROMES
Syndrome Associated Gene
Familial retinoblastoma RB1
Li-Fraumeni TP53
Familial adenomatous polyposis
APC
Hereditary nonpolyposis colorectal cancer
MLH1,2,6PMS1,2
Wilms’ tumor WT1
Breast and ovarian cancer
BRCA1,2
Von Hippel-Lindau VHL
Cowden PTEN
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Generally more screening: caught earlierLifestyle changes to help prevent itAff ect prognosis & treatment if cancer occursCan pass info on to family – may be aff ected as well
BENEFITS OF KNOWING
Bode & Dong, 2009.
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Once related genes are found, often look for why they cause increased likelihood
Can use this info to craft new ways of treating cancers2
Specific drugs to target proteins made by mutated genes HER2 oncogene – trastuzumab (Herceptin®), lapatinib
(Tykerb®) to attack HER2 positive cells BCR-ABL – target products to prevent chronic myeloid leukemia
Reactivate methylated (turned off) genes hypomethylating agents, ie decitabine (Dacogen®)
Test if a drug will work Some drugs don’t work
GENETIC TREATMENT OF CANCERS
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BRCA (TIMELINE)
McPherson et al, 2000.
1800s: ‘Latent state’ BC
1920s: More likely to die of BC if your mother did
1990: Correlation discovered between 17q21 (10x likelihood w/ mystery gene)
1994: BRCA1 discovered
1995: BRCA2 discovered
20??: BRCA3?
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BRCA (ISOLATION)
King, 2014.
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BRCA (FUNCTION)
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Gene patents (2013) No for natural Yes for artificial
INTERESTING ETHICS
Holman C. (2008). Science 322:198-99. Retrieved from http://www.patentdocs.org/2008/12/science-article-should-help-allay-fears-concerning-gene-patents.html
Genetic Discrimination By insurance agencies/
employers Led to… Genetic Information
Nondiscrimination Act (2008)
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1. Bode A. M. & Dong Z . (2009) . Cancer prevent ion research- then and now. Nat Rev Cancer 9 (7 )508-16 .
2. Genet i cs and Cancer. (2014) . Ret r ieved f rom ht tp : / /www.cancer.org /cancer /cancercauses /genet i csandcancer / index
3. Genet i c in format ion Nond isc r im inat ion Ac t o f 2008 . (2014) Ret r ieved f rom ht tp : / /www.genome.gov/10002328
4. Ha l l J . M. e t a l . (1990) . L inkage o f ear ly- onset fami l i a l breast cancer to chromosome 17q21 . Sc ience , 250 (4998)1684-89 .
5. K ing M-C. (2014) . “The race” to c lone BRCA1. Sc ience , 343 (1492)1462-65 .6. McPherson K . e t a l . (2000) . Breast cancer—epidemio logy, r i sk fac tors , and genet i cs .
Br i t i sh Medica l Journa l , 321 (7261)624-8 .7. Than K . (2013) . Takeaways f rom the Supreme Cour t ’s gene patent dec i s ion . Nat iona l
Geograph ic .
REFERENCES
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Cancer Immunology-The relationship between cancer and the immune system-
Inseong Joe
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What is Cancer Immunology?
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Why Cancer Immunology?
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Immunoediting: Process by which a person is protected from cancer growth and development of tumor immunogenicity by their immune system
The Connection
Elimination Equilibrium Escape
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EliminationPhase 1
• Initiation of antitumor immune response• Induction of inflammatory signals
Phase 2
• IFN-gamma induces tumor death + promotes production of chemokines• Recruitment of more immune cells
Phase 3
• Natural killer cells & macrophages transactivate one another• More tumor death via apoptosis
Phase 4
• Tumor-specific T cells at tumor site and cytolytic T lymphocytes destroyantigen-bearing tumor cells remaining
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• Equilibrium Phase: Lymphocytes and IFN-gamma exert selection pressure on tumor cells
• Escape Phase: Tumor cells continue to grow and expand
Equilibrium and Escape
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• Patient’s immune system stimulated to fight tumors
Tumor Immunotherapy
NonspecificImmunotherapy
Antigen-specificImmunotherapy
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• Bacile Calmette-Guerin (BCG) therapy– Administration of weakened forms of
mycobacterial strain– Probably activates macrophages and lymphocytes
• Cytokines– Direct antitumor effect– Indirect enhancement of antitumor immune
response• Cell therapy
– Transfer of live, whole cells into patients
Nonspecific Immunotherapy
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Specific Immunotherapy
AdoptiveTransfer Vaccination
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• All therapies that consist of transfer of components of immune system already capable of mounting immune response
• Antibody Therapy• Adoptive transfer of T cells
Adoptive Transfer
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• Place antigen within patient so that immune systems can be provoked to unleash killer T cells
• Design antigens that selectively activate specific T cells to kill cancer cells
• Success depends on – Mode of antigen delivery– Choice of adjuvant– Particular antigen
Vaccination
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cervical cancer + HPVPaige Cote
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HPV
● More than 150 types of virus, ~40 that are easily spread. >50% of sexualy active individuals
● Types 16 and 18 (high risk) are responsible for most cervical cancers
● Most high risk infections go away within 1-2 years
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HPV and Cancer
● Can cause cervical, anal, vaginal, vulvar, and penile cancers. Plus the cancer of the oropharynx.
● Cancer more likely when combined with certain risk factors
● Prevent with abstinence or vaccines● Testing only available for women
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How?
● Epithelial Cells● Proteins● Time● High grade lesions● Other factors in your health
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This is what it looks like, sorry!
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Removal
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CANCER BIOINFORMATICSShrinidhi Thirumalai
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Why Bioinformatics?
Problem: High Variation in Cancer:
• Severites, Resistance, Origins,
Genes, environment etc.
• Makes it extremely hard to quantitatively assess specific treatments
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Why Bioinformatics?
Solution: Systems Clinical Medicine with Bioinformatics as a tool
• Iterative process between:• data-driven computational and mathematical models• model-driven translational and clinical investigations.
• Takes a variety of factors such as environment and genes into account
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Applications• Personalized Medicine
• Pharmaceutical drug/vaccine development• production, delivery and safety• Ex: Most optimum patient groups to focus on first
• Discovery of biomarkers• effective diagnosis
• Design of combinatorial therapies• Ex: Dosing and administration patterns
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Biomarkers
• Phenotypes related to early diagnoses
• measurements to monitor progress of disease
• measurements to monitor response to therapy
• predictors for the improvement of life quality
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Network Biomarkers• Set of biomarkers and their
interactions
• Analyze gene or protein expression data and other high-dimensional profile data with over thousands of measurements
• Achieved higher accuracy
• Dynamic Biomarkers: connect to clinical informatics as well (patient complaints, histories, etc)
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Molecular Markers of
CancerAnna Knapp
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Biomarkers
From Wikipedia
Lynn Henry et. Al.
• Can be almost any type of molecule
• Protein, nucleic acids, antibodies, peptides etc…
• Can also be a change in a group of things – gene expression, metabolic signatures, etc…
• Detection is non-invasive
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DetectionTechniques
• Assays• Used to detect the presence
of a small number of markerso Proteins often measured using standard
antibody testing
• Protein profiling – Higher throughput methods of detecting and quantifying multiple Biomarkerso Mass Speco Chromatographyo surface-enhanced laser
desorption/ionization
• QRT-PCRo Used to measure gene expressiono Faster than microarrays
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HYPERTHERMIA TO TREAT
CANCER
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HYPERTHERMIA TO TREAT
CANCER
Felix Kinger
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WHAT DOES IT MEAN? Hyperthermia = body temperature that
is higher than normal Can be used to make other treatments
more effective Can kill cancer cells outright
(but also normal cells and tissue!)
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LOCAL HYPERTHERMIA
Local hyperthermia (high heat):very high temperatures to destroy a small area of cells
Two ways of application1) External:
High energy waves are aimed at tumor from outside the body2) Internal:
A thin needle or probe is put right into the tumor and releases energy
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HOW?
Microwaves Ultrasound waves Radiofrequency ablation (RFA)
-> high energy radio waves-> internal application-> creates heat between 122-212F-> most effective for liver, kidney, lung cancer
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REGIONAL HYPERTHERMIA
Regional hyperthermia (low heat):temperature of a part of the body is raised by a few degrees higher then normal
Supportive effect, combined with other treatment
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HOW?
Regional perfusion
-> Blood supply from part of the body is isolated-> Blood goes into heating device and back to the body-> Chemotherapy may be applied at the same time-> Temperature ranges from 104F to 113F-> Mostly to treat cancer in arms and legs
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WHOLE BODY HYPERTHERMIA
Mostly used against metastatic cancer
Heating blankets Warm water immersion Thermal chambers Temperature around ‘fever-level’ (100F)
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PROS & CONS
PROS CONS
- Can destroy tumors without surgery
- Can be combined with other treatment methods
- Holds potential in the future
- experimental technique- Requires special and not
easily accessible equipment
- Can cause damage to skin, muscles and nerves near the treated area
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http://www.cancer.org/treatment/treatmentsandsideeffects/treatmenttypes/hyperthermia
http://www.cancer.gov/cancertopics/factsheet/Therapy/hyperthermia
http://www.wjgnet.com/1948-5204/full/v3/i12/WJGO-3-169-g001.jpg
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Laser Treatment for CancerKevin Suzuki
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What is Laser Treatment
● Lasers are used to burn away abnormal or cancerous cells in a process known as laser ablation
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Methods of Using Lasers
1. Laser can shrink or destroy tumor with heat2. Laser can activate a chemical
(photosensitizing agent) that kills only the cancer cells
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Types of Lasers
-CO2 lasers: can cut or vaporize tissue with little bleeding and is used to remove thin layers from surface-Argon lasers: Treat skin problems and eye surgeries and is used in photodynamic therapy-Neodymium: Yttrium-Aluminum-Garnet Lasers: used for hard to get places like esophagus and is much stronger
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What Cancers is this Applicable to?
● Used for precancerous changes and cancers on the surface of body like basal cell skin cancer (Photodynamic Therapy)
● Cervical cancer, Penile cancer, Vaginal cancer, Vulval cancer and melanoma of the eye
● Some internal organs like oesophagus and trachea and early stages of non small cell lung cancer (85-90%)
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Photodynamic Therapy
● Phototherapy using non toxic light-sensitive compounds that are exposed selectively to light where they become toxic to targeted malignant and other diseased cells
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Photodynamic Therapy Continued
3 Key components to success
1. Photosensitizer is excited from 2. Light Source which produces3. Oxygen which is reactive and actively
attacks any organic compounds it encounters
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Advantages of Photodynamic Therapy
- Cancer cells can be singled out and destroyed
- Damaging effect of photosensitizing agent happens only when drug is exposed to light
- Mild side effects
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Cons of Photodynamic Therapy
- Laser cannot hit deep tumors- Photosensitizing agents can leave people
very sensitive to light, causing sunburn- like reactions after very brief sun exposure
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Laser Therapy for Cervix, Vagina or Vulva
● Goal: Doctor uses laser to burn away abnormal cells
● Steps: 1) Doctor puts a speculum into vagina and holds it open and puts anaesthetic onto cervix and vaginal wall to numb it
● 2) Points laser at abnormal area where laser burns away abnormal tissues
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Laser Therapy for Penile Cancer
● Used for only early cancer of penis● Steps: 1) Doctor puts anaesthetic on penis● 2) Doctor uses powerful beam that acts like
a knife which cuts away tumor but doesn’t go deep into tissue
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Laser Therapy for Cancer in Body (Endoscopic Resection)
● Goal: Laser cuts and burns away cancerous tissue
● Ex. Lung cancer: 1) Doctor uses bronchoscopy to position laser and tube has a light at end and an eyepiece so doctor can see any abnormal areas
● 2) Doctor positions end of tube close to tumor and laser cuts cancerous tissue
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Laser Treatment of Esophagus
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Advantages:
● Seals off blood vessels as it cuts so minimizes bleeding
● Lasers are more precise than blades● Heat produced by laser sterilizes edges of
body tissue it is cutting● Operating time is shorter● Healing time is often shorter
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Cons of Laser Surgery
Few doctors know how to use lasersVery expensive and bulky Strict safety precautions must be followedEffects may not last as long so some treatment may have to be repeated
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Works Cited
http://www.cancer.org/cancer/lungcancer-non-smallcell/detailedguide/non-small-cell-lung-cancer-what-is-non-small-cell-lung-cancerhttp://www.cancerresearchuk.org/about-cancer/cancers-in-general/treatment/other/laser-treatment http://www.cancer.org/treatment/treatmentsandsideeffects/treatmenttypes/lasers-in-cancer-treatment
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Photodynamic therapy
• Phototherapy using nontoxic light sensitive chemicals called Photosensitizing agents
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Photodynamic Therapy
• Photosensitizing agents applied to skin or in the blood
• 24-72 hours later agents has left normal cells but remain in tumors
• Large tumors may shrink but not be destroyed
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Photodynamic Therapy
• Outpatient Procedure• Less invasive• Repeatable• Used with other therapies• No scar tissue• Even used outside the
body Extracorporeal photopheresis (ECP) for cancers that affect blood
• No long term side affects
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Photodynamic Therapy
• Several short term side affects• Light can’t penetrate more than about 1 cm• Can’t break down large tumors• Can’t treat metastasized tumors• People who have certain blood diseases or allergies
to porphyrins cannot undergo PDT
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Photodynamic Therapy