Cancer Biology Final Flashcards
(94 cards)
1
Q
How are antimetabolites used for treatment?
A
They resemble substances involved in normal cellular metabolism and disrupts pathways of DNA synthesis and repair; killing cancer cells.
2
Q
Anti-Her2 Ab/Herceptin
A
Treats HER2-Positive breast cancer (which responds to progesterone). Herceptin binds to HER2, inhibiting the cancer cells by blocking the growth signal, recruiting NK cells, and preventing angiogenesis.
3
Q
Describe hybridoma production
A
Tumor cells are injected into a mouse, whose B-cells create antibodies that can be isolated, fused with myeloma cells that can allow the b-cell to be immortal (hybridoma), and then introduced to a human patient.
4
Q
Properties of cancer cells needed in order to invade adjacent tissues.
A
- Decreased adhesion, expresses less E-Cadherin
- Increased motility, cells are able to move away from other cells
- Increased MMP production, proteases that can cut through the extracellular matrix
5
Q
How does aspirin prevent cancer?
A
It is anti-inflammatory. Increases CTL (Cytotoxic T-lymphocytes) and inhibits angiogenesis.
6
Q
Methods for cervical cancer screening
A
- Pap-smears (cervical tissue swabbed and looked under microscope)
- Vinegar test (used in countries like India)
7
Q
What is PCR (Polymerase Chain Reaction)
A
A laboratory nucleic acid amplification technique used to denature and renature short segments of DNA. Helps to isolate and replicate genes of interest.
8
Q
How does radiation therapy induce cell death?
A
- By activating P53, inducing apoptosis
- Inducing mitotic death
9
Q
Cancer grade
A
A description of a tumor based on how abnormal the tissue looks under a microscope.
10
Q
Methods for lung cancer screenings
A
- Low-dose CT scanning (mostly done for smokers or those with higher risk)
11
Q
How are antibiotics used for treatment?
A
Certain antibiotics, like streptomycin, doxorubicin, and doxycycline can hurt the DNA synthesis of cancer cells similarly to how it kills bacteria.
12
Q
Angiogenesis
A
The process of cancer cells stimulating the development of blood supply by growing new blood vessels from existing blood vessels.
13
Q
Specificity
A
Ability for a test to accurately identify a disease as being absent. (Looking for a True Negative, can sometimes get a false positive)
14
Q
Macrophage therapy
A
Macrophages are programmed to ignore the CD47 signals released by cancer cells (which normally act as a ‘do not eat me’ signal), killing cancer cells.
15
Q
When is radiation therapy used for treatment?
A
If cancer has invaded the adjacent tissues and possibly metastasized or surgery is not practical.
16
Q
Bacterial transduction
A
Using bacteriophage to insert genes/DNA into bacteria and have it produced within.
17
Q
Complement system (CDC)
A
Complement-dependent cytotoxicity (CDC) sees complement proteins binding to antibodies that are bound to tumor antigens. This system of proteins punch holes into the tumor cell, killing it.
18
Q
Sensitivity
A
Ability for a test to accurately identify a disease as being present. (Looking for a true positive, can sometimes get a false negative).
19
Q
How does BRC-ABL/Philadelphia Chromosome cause cancer?
A
Translocation occurs between chromosome 9 and 22, resulting in a fused BRC-ABL protein, which decreases apoptosis.
20
Q
What are the mechanisms for oncogene mutation?
A
- Point mutations: A single or multiple nucleotide base change. (RAS)
- Gene amplification: (WITHOUT CHANGING DNA SEQUENCE) DNA replicated numerous times, creating hundreds/thousands; this results in expression of abnormally high levels of proteins. (MYC)
- Chromosomal translocation: Process in which one piece of one chromosome is broken off and brought to another chromosome. (BRC-ABL/Philly)
- DNA rearrangement: Movement of DNA base sequences in a particular region of a chromosome, altering the expression or structure of a proto-oncogene in that region. (TRK)
- Insertional mutagenesis: In which viral DNA is integrated into the host’s chromosome, leading to the disruption or activation of a certain gene, altered expression. (v-SRC)
21
Q
Chemoprevention
A
The use of specific chemical substances to protect against cancer.
22
Q
Tamoxifen
A
A drug that binds to estrogen receptors of breast cancers and inhibits estrogen-driven cell proliferation. NOT used for uterine cancer prevention, as it can induce it.
23
Q
When is chemotherapy used for cancer treatment?
A
When the cancer has already metastasized as drugs can reach cancer cells through the bloodstream.
24
Q
How are hormones used for treatment?
A
Hormones involved with the cancer cell growth are removed or inactivated. (i.e, estrogen responsive breast cancer)
25
What are oncogenes?
Genes whose presence can contribute to uncontrolled cell proliferation and cancer. Always on.
26
Describe MMPs (Matrix metalloproteinase)
An enzyme that breaks down the extracellular matrix and allows endothelial cells to migrate and organize new blood vessels.
27
Describe inflammation
Process in which all of your immune cells rush to the site of infection/damage through leaky blood vessels as a result
of histamine release.
28
Killer T-Cells/CTLS and Cancer
These kill the cancer cells directly.
29
Gleevec
Targets Philadelphia Chromosome, which is related to Chronic myelogenous leukemia, blocking cell proliferation by removing the CML enzyme’s ability to use ATP to power cancer protein production.
30
Describe a liquid biopsy
A way to identify cancer at its earliest stages, in which physicians examine ctDNA (tumor DNA fragments) and CTCs (circulating tumor cells) released into circulation by tumors. Shown promise in identifying lung, breast, and colorectal cancer.
31
List the immune organs and their functions.
Bone marrow: Where ALL immune cells originate.
Thymus: Where T-cells are 'educated' and mature. Larger in children.
Spleen: Filters pathogens in the blood, B and T cells present.
Lymphatic System: Collects the fluids of the body's tissues before returning them to the body.
Lymph Nodes: Assist with adaptive immunity.
32
What are phytochemicals?
Plant-derived molecules.
33
Describe the seed/soil hypothesis.
Nonrandom distribution of metastases arise in part because individual cancer cells have a special affinity for the environment provided by particular organs.
- Explains why breast/prostate cancers tend to metastasize into the bones, where the environment is rich for the cancer.
34
List some oncogenes
1. RAS
2. BRC-ABL ("Philadelphia Chromosome")
3. MYC
4. TRK
5. v-SRC
35
Describe laser surgery
Using a laser beam to cut through cancer.
36
Adaptive immune cells
T-Cells, B-Cells
37
Two angiogenesis inhibitors
1. Endostatin
2. Angiostatin
38
Primers
Short piece of single stranded DNA to mark the DNA needed to be copied.
- Forward (Start)
- Reverse (End)
39
Taq DNA polymerase
Enzyme which adds complementary nucleotides to a DNA strand during DNA synthesis. Derived from heat-stable bacteria.
40
NK Cell therapy
The NK cell binds to an antibody that is
bound to a cancer cell, and releases chemicals to kill the cells directly. This is known as ADCC, or Antibody-dependent cell-mediated cytotoxicity.
Tumor debris are picked up by dendritic cells and presented to B cells, which help to create tumor antibodies.
41
Antioxidant found in high concentrations within grapes
Resveratrol
42
Adaptive immunity
Immunity that results from an 'education'.
- Specific, memory via antibodies
- Delayed
43
Why do certain cancers metastasize into specific areas of the body?
Blood flow patterns.
- Stomach/Colon cancers metastasize to the liver.
- Cancers from the lungs metastasize easily as most of the body's blood travels into the lungs and out at some point.
44
How are alkylating/platinating agents used for treatment?
Alkylating: These highly-active organic molecules trigger DNA damage by linking themselves directly to DNA.
Platinating: These substances contain platinum that crosslink DNA.
45
Innate immune cells
Macrophages, neutrophils, natural killer cells, dendritic cell, mast cell, basophils
46
Describe the relationship between Natural Killer cells and cancer
NK cells, when bound to cancer antigens, release cancer-killing toxins. This is known as Antibody-dependent cellular cytotoxicity (ADCC).
47
List the forms of surgery used for cancer treatment
1. Traditional Surgery
2. Cryosurgery
3. Electrosurgery
4. Laser Surgery
5. High intensity focused ultrasound (HIFU)
48
Steps for PCR
1. Denaturing: At 96*C, double stranded DNA denatures
2. Annealing: At 50*-60*C, primers anneal to DNA template
3. Elongation: At 72* C, Taq DNA polymerase adds nucleotides to primer, copying template
49
Describe the relationship between macrophages and cancer
Macrophages can be both anti and pro-cancer.
- Anti: 'Eats' cancer cells and rids the body of dead cancer cells
- Pro: Can contribute to chronic inflammation
50
Describe electrosurgery
High frequency electrical current to kill cancer cells. Used for skin and mouth cancers.
51
Describe HIFU
High intensity focused ultrasound which focuses energy at the selected part of the body. Used predominately for prostate cancer treatment.
52
How does MYC cause cancer?
Transcription factor replicated, creating high levels of cell proliferation proteins. High levels of MYC proteins induce high levels of gene expression, promoting uncontrolled cell proliferation.
53
TRegs and Cancer
Regulatory immune cells that prevent autoimmune conditions by suppressing the immune system, encourage cancer growth in the process.
54
Cons for regular cancer screening
Overdiagnosis/overtreatment
55
Methods for breast cancer screening
1. Self examination (NOT recommended)
2. Regular mammograms
56
Steps of metastasis
1. Invasion into surrounding tissues
2. Entering the blood stream and traveling throughout the body.
57
Adaptive cell transfer
Lymphocytes from the tumor site are taken and grown in petri dish. The T-cells from the site, TUMOR INFILTRATING LYMPHOCYTES WITH THE MOST TUMOR KILLING PROMISE, are cultured and proliferated with interleukin-2 to enhance their cancer destroying properties. These T-cells are injected back into the patient after their pre-existing lymphocytes are destroyed.
58
Biopsy
A secondary test of tissues after a cancer screening shows positive results. Also helps to grade tumor.
59
Multivitamin impact on cancer
15+ year intake of multivitamins can reduce risk of colorectal cancer.
60
Plan A for the Immune System
Blocking entry from pathogens.
1. Skin (acidic, covered in healthy bacterial flora, layers of dead cells)
2. Lungs (mucus and cilia)
3. Stomach (acid)
4. Urinary tract
5. Mouth (digestive enzymes in saliva)
6. Eyes (tears)
61
List phytochemicals and modes of cancer prevention.
1. Lycopene -> Tomatoes, a potential antioxidant.
2. Isothiocyanates -> Broccoli, cauliflower, etc; could lower the risk of prostate/colorectal/lung cancers. Anti-inflammatory, stops angiogenesis, and induces apoptosis.
3. Epigallocatechin Gallate (EGCG) -> Green tea, antioxidant; also stops cell proliferation and angiogenesis, induces apoptopsis/cell cycle arrest.
4. Resveratrol -> Grapes, antioxidant.
5. Isoflavones (Geinstein) -> Soy, slows/stops cancer metastasis.
6. Sulfides -> Garlic, stimulates DNA repair while inducing apoptosis. Decreases cell proliferation.
62
Describe VEGF (Vascular endothelial growth factor)
An angiogenesis stimulator found within most cancer cells. Increases MMP production, endothelial cell proliferation, and organizes cells into new blood vessels.
63
How does TRK cause cancer?
Two growth factor receptors are permanently joined together by a coiled tail, which signals cells to proliferate non-stop.
64
CRISPR T-Cell therapy
Cytotoxic T Lymphocytes (CTL) are isolated from a cancer patient. T-cell receptors (TCR) are programmed to recognize cancer cells. CTLs attack and kill these cells through antigen presentation.
65
Describe cryosurgery
Uses liquid nitrogen spray to freeze and kill cancer cells. Used for skin, cervical, and prostate cancers.
66
What is missing from a negative control PCR?
DNA template.
67
Plan B for the Immune System
Innate and adaptive immune cells work together to kill pathogens.
1. Phagocytosis
2. Natural killer cells induce apoptosis
3. Dendritic cells present antigens to t-cells
4. B-cells create antibodies
68
What is E-Cadherin?
The ‘hook’ that keeps cells attached to primary tumors, expressed in smaller quantities by cancerous cells.
69
Dendritic cell therapy
Tumor cell antigen is bound to a dendritic cell, which is infused back into the patient and presented to a T cell, activating the immune system against the cancer.
70
Forms of innate immunity cancer therapies
1. Dendritic cell therapy
2. Macrophage therapy
3. NK cell therapy
71
How do antioxidants prevent cancer?
Antioxidants donate an electron to free radicals and therefore preventing DNA damage.
72
Pros for regular cancer screenings
With regular cancer screenings, someone can catch their cancer early, prior to any significant tissue invasion and/or metastasis.
73
Cancer stage vs Survival rate
The more advanced a cancer is (local vs regional vs distant), the lower the rate of survival.
74
Describe the ECM (Extracellular matrix)
A large network of proteins and molecules that surround tissues and provide support, structure.
75
Vasculogenesis
Process of blood vessel formation in EMBRYONIC development. Undifferentiated cells are converted to form the lining of the blood vessels called endothelial cells.
76
What are the steps for clinical trials?
0. Pre-clinical trials, including formula creation and animal trials.
1. Safety: Looking for safe doses.
2. Efficacy: Preliminary effectiveness testing.
3. Randomized double-blinded trials.
4. Production/ongoing monitoring of long-term side-effects
77
Common signs/symptoms of cancer
- Unintentional weight loss of 20+ lbs
- Unexplained bleeding
- Cramping, general pain/aches
- Night sweats/heat flashes
Difficult to use these symptoms alone as they are incredibly broad, which is why someone may not be diagnosed early without screening.
78
How does RAS cause cancer?
C to A nucleotide base change, leaving the RAS receptor in a constant active position. Results in the uncontrolled release of RAS proteins.
79
Dendritic cells and cancer
Dendritic cells activate the T-cells which can formulate an immune response against cancer.
80
Methods for prostate cancer screening
1. PSA (prostate-specific antigen) blood tests
2. Physical examination
81
Methods for colorectal cancer screening
1. Colonoscopy
2. Fecal immunochemical tests
3. Guaiac-based fecal blood tests
82
List the types of drugs used for chemotherapy.
1. Antimetabolites
2. Alkylating and platinating agents (heavy metals)
3. Antibiotics
4. Hormones
83
Nucleotides
Free floating single nucleotides to put added by Taq DNA polymerase to the primers to make DNA sequence copies
84
How does v-SRC cause cancer?
An encoded version of SRC, v-SRC, is created which locks SRC protein into a state of constant production, allowing virus to proliferate nonstop.
85
Impact of Vitamins A and E and cancer
They found to have no impact on preventing cancer. High vitamin A intake can be associated with increasing cancer risk.
86
Anti-CD20 Ab/Rituximab
Used to treat non-Hodgkin's' B cell lymphoma. CD20-specific antibodies are injected into patients, which bind to cancerous and mature B cells that promotes an immune response that eliminates these B cells. As immature B-cells do not produce CD20, they’re allowed to develop into normal B cells.
87
What is a bacteria plasmid?
This acts as an extra piece of DNA for gene expression, like antibiotic resistance. This is exchanged via (sex) pili, how the bacteria reproduces (bacterial conjugation).
88
Describe Photodynamic Therapy
A form of cancer treatment.
Drugs known as photosynthesizers are administered and absorbed by cancer cells. When exposed to a specific wavelength, these drugs are activated, damaging and killing cancer/tumor cells.
89
DNA Template
Double-stranded genomic DNA isolated from the cells of organism
90
Innate Immunity
The immune system at its base level, what we have when we are born.
- Nonspecific, no memory
- Immediate
91
How do we force bacteria to take in pGLO plasmid for transformation?
The bacteria are made hungry/uncomfortable with a leaky cell wall so that they are more likely to take in GFP proteins. This is through heat shock.
92
Coley's Toxins
Essentially how immunotherapy was discovered. In 1891, Coley injected streptococcal organisms into a patient with inoperable cancer. This infection helped to shrink the tumor.
93
Signal transduction
Growth factor meets receptor -> activation -> inactivated downstream effector activated -> transcription factor made active -> signal enters nucleus -> gene expression.
94
CRISPR
Derived from bacteria. Gene editing technology that can be used as gene therapy. Used to cut/edit portions of a gene.
