CH 10 NEOPLASIA Flashcards
1
Q
What is the term for the process by which a normal cell becomes a neoplastic cell?
A
Cell transformation
2
Q
Describe the location of cell DNA mutations that cause neoplasia
A
In specific gene loci that alter cellular function in fundamental ways
3
Q
Name some examples of neoplastic alterations of cell function
A
- DNA repair
- Growth regulation
- Differentiation
- Cell division
- Apoptosis
4
Q
Why do neoplastic cell populations display heterogeneity?
A
Instability of neoplastic cell genome
5
Q
What is the term for the process by which normal cells become malignant?
A
Carcinogenesis
6
Q
Name 4 stages of tumour development
A
- Initiation
- Promotion
- Malignant conversion
- Progression
7
Q
What is the term for chemicals that induce neoplastic changes?
A
Initiating agents
8
Q
What initiating agent is found in by products of combustion?
A
Polycyclic aromatic hydrocarbons (PAHs)
9
Q
What initiating agents are associated with food preservation and some artificial food dyes?
A
Nitrosamines and aromatic amines
10
Q
Which are 2 other initiators that are not chemicals?
A
Ionizing radiation and viruses
11
Q
What is involved in tumor promotion?
A
Stimulation of cell division of initiated cells
12
Q
Why is rapid cell division dangerous?
A
Higher rate of error and higher diversity
13
Q
Which cells in a diverse cell population will thrive best?
A
Those with highest proliferation rate
14
Q
What makes a substance a tumour promoter?
A
Alter intracellular signalling systems that control cell division
15
Q
Name some examples of chemical promoters
A
- Benzoyl peroxide
- Phenol
- Estrogens
16
Q
Name some non-chemical promoting factors
A
- UV light
- Tissue irritation
- Bile acids
17
Q
What is another term for initiators
A
Mutagens
18
Q
What is malignant conversion?
A
Further genetic mutations in destabilized cells of promoted cell masses
19
Q
What may cause a tumour to regress?
A
Exposure to promoting factor ceases
20
Q
What is tumour progression?
A
Acquisition of malignantly aggressive traits through natural selection
21
Q
Name 5 examples of invasive phenotypic traits
A
- Proteases
- Genomic instability
- Loss of tumour suppression
- Immunological resistance
- Loss of cell binding
22
Q
What are the two categories of causes for neoplasia?
A
Endogenous (genetic) and exogenous (environmental)
23
Q
Which causes of neoplasia are more significant?
A
Environmental
24
Q
How does ionizing radiation relate to neoplasm?
A
Cause breaks in DNA strands, increasing rate of mutagenesis
25
What are environmental carcinogens that act synergistically?
Co-carcinogens
26
What are chemical carcinogens that must first undergo metabolic activation by the cell in order for them to initiate/promote tumour development?
Pro-carcinogens
27
Which WHO agency manages the full list of carcinogens and classifications?
International agency for research on cancer (IARC)
28
Which group of carcinogens has the strongest association with cancer?
Group I carcinogens
29
Define alkylating agents
Compounds that covalently link alkyl groups to biomolecules
30
How do alkylating agents alter cells?
Formation of cross-linking between strands of DNA, causing altered transcription
31
What are 4 places alkylating agents are found?
1. Industrial processes
2. Nature
3. Anti-neoplastic drugs
4. Cancer research
32
What is a malignancy that arises as a result of treatment of a pre-existing malignancy?
Secondary malignancy
33
Name 2 sources of nitrosamines
1. Nicotine
2. Meat preservatives
34
What kind of cancers are associated with nitrosamines?
GI tract
35
What is the toxin found in Aspergillus?
Aflatoxin
36
Name 3 examples of carcinogenic metals
Cadmium, chromium, nickel
37
What are molecules that acquire electrons from other molecules?
Oxidants
38
When would a molecule be considered oxidized?
When it loses electrons
39
What gives molecules capacity to strip electrons from other molecules?
Characteristics of electrons in outer orbital
40
When is oxidation present in normal biological processes?
Transfer of energy from bonds of energy substrates (e.g. fat, carbs, proteins)
41
Why is oxidative damage important in carcinogenic processes?
Denaturation of proteins, DNA mutation
42
What is unique about free radicals?
Have unpaired electron in fourth quantum number (spin number), which makes them more reactive
43
What are 3 sources of free radicals in cells?
Air, food, conversion
44
What are 3 structures in cells that generate reactive oxygen species?
1. Mitochondria
2. Peroxisomes
3. Endoplasmic reticulum
45
What are 3 examples of DNA damage caused by oxidation?
Deletions, cross linking, strand breaks
46
What homeostasis is necessary in cells to prevent carcinogenesis?
Between oxidative DNA injury and DNA repair
47
What 2 things may tilt the balance toward carcinogenic changes?
1. More intense exposure to oxidation
2. Reduced capacity to defend against normal oxidation
48
What may complicate patterns of cancer inheritance?
1. Involvement of multiple alleles
2. Gene-environment interactions
49
What are genes that, when mutated, are strongly linked to carcinogenesis?
Oncogenes
50
What are oncogenes that are not mutated?
Proto-oncogenes or cellular oncogenes
51
What are viruses that insert a viral oncogene into host cells?
Oncogenic viruses
52
What causes metaplasia?
Chronic irritation to tissues
53
What makes dysplasia different from metaplasia?
Abnormal morphology (e.g. shape, size, nucleus/organelles, division)
54
Why do pathologists classify dysplasia using morphological criteria?
Determine probability of tissue proceeding to necrosis or transformation
55
What is the term for diverse and abnormal morphology upon microscopic examination?
Pleiomorphism
56
What is the term for the state of interrupted or diverted differentiation?
Anaplasia
57
How is anaplasia related to malignancy?
The less differentiated, the more malignant
58
What are some examples of anaplastic protein products?
1. Lung carcinomas secreting ADH
2. Neoplasms producing fetal proteins
59
Why is the decreased cell adhesion of neoplastic cells significant?
Loss of normal contact inhibition
60
Name 5 factors that influence tumour growth rate
1. Cell type
2. Level of differentiation
3. Vascularization
4. Anti-tumour response
5. Hormones
61
What is another term to describe growth rate?
Cellular doubling time
62
Name 7 ways benign tumours are different from malignant tumours
1. Cells resemble parent tissue
2. Few mitotic figures
3. Grow slowly
4. Well-organized
5. Encapsulated
6. Less vascularized
7. Less complications
63
Name 4 ways benign tumours can cause serious complications
1. Pressure atrophy
2. Obstruction
3. Compression of cranium/spinal cord
4. Transformation
64
Name 6 ways malignant tumours are different from benign tumours
1. Little resemblance to parent tissue
2. Abnormal/weak cohesiveness
3. Spread in "fingers"
4. Abnormal mitotic figures
5. Well vascularized
6. No capsule
65
What happens after tumour emboli enter the bloodstream?
Become entrapped in capillary networks and establish a secondary tumour
66
How do malignant tumours develop their own blood supply?
Tumour angiogenesis factors
67
What kind of tissues are favoured as the target of tumour emboli?
Soft tissues (e.g. lung, liver)
68
Name 6 effects of malignant tumours
1. Inflammation
2. Mechanical pressure/obstruction
3. Enzymatic destruction
4. Hemorrhage/anemia
5. Starvation/cachexia
6. Hormone abnormalities
69
What are 3 ways malignancy can affect blood?
1. Erosion of blood vessels: slow blood loss
2. Bone marrow neoplasia: suppression of hematopoiesis/thrombopoiesis
3. Metastases to bone marrow
70
How does liver malignancy contribute to anemia?
Reduced synthesis of coagulation factors
71
How does kidney malignancy contribute to anemia?
Impaired production of erythropoietin
72
How does intestinal malignancy contribute to anemia?
Reduced absorption of vitamin B12 (required for erythropoiesis)
73
How does impaired immune reactions as a result of malignancy contribute to anemia?
Hemolysis of blood cells
74
What is another process associated with malignancy that leads to hemolysis of blood cells?
Activation of cytokines
75
Name 3 ways mutated cells die
1. Apoptosis
2. Necrosis
3. Autophagy
76
What is the term for spontaneous resolution of malignancy without treatment?
Spontaneous regression
77
What is the term for ongoing detection abnormal antigens?
Immune surveillance
78
What is the term for cell-mediated removal of abnormal cells?
Immuno-editing
79
What is the term for imperfect activation of the immune system so it holds the tumour at bay without entirely destroying it?
Immune equilibrium
80
What is the term for when mutations completely block the immune system from being able to detect/destroy abnormal cells?
Immune escape
81
Why are oncofetal proteins expressed by neoplastic cells, and what is one example?
Cells fail to differentiate fully; alpha-fetoprotein
82
Name one example of malignancy caused by viral infection
Burkitt's lymphoma (EBV)
83
Neoplasm classification is generally based on what 2 things?
Cell of origin, benign/malignant
84
What are the 2 categories of solid tumours, and what are their origins?
Carcinomas: Epithelium
Sarcomas: Mesoderm
85
Name 4 methods for biopsy analysis
1. Cellular
2. Chemical (staining)
3. Immunological (antigens)
4. Molecular (DNA/proteins)
86
Name 3 biopsy techniques
1. Fine needle aspiration
2. Large bore needle
3. Excision
87
What does TNM refer to?
T: tumour (size and extent)
N: nodes
M: metastasis
88
Name 4 principles of cancer therapy
1. Chemo is best against small active tumours with rapid division and extensive blood supply
2. Surgery can improve the effectiveness of chemo
3. Adjuvant chemotherapy can help by reducing mico-metastases
4. Combination therapy permits the use of lower doses of each individual drug to reduce damage
89
Name 4 surgical techniques
1. Cryosurgery
2. Electrosurgery
3. Chemosurgery
4. Laser
90
What is the term for internal radiation that involves implanting a radioactive device in/near the tumour?
Brachytherapy
91
Why do common side effects of radiation include hair loss, stomatitis, malabsorption, anemia, and hemorrhage?
Tissues that replace themselves quickly are more affected by the radiation
92
Name 4 purposes of chemotherapy
1. Reduce tumour size
2. Improve effectiveness of other treatment
3. Reduce metastases
4. Reduce pain
93
Name 3 categories of chemo drugs
1. Traditional highly toxic, low specificity
2. High specificity
3. Immune mediators
94
Name two kinds of cytotoxic drugs
1. Cell cycle non-specific agents
2. Cell cycle specific agents
95
Name 3 groups of cell cycle specific agents
Alkylating agents
Anti metabolites
Antibiotics
96
What does it mean that traditional cytotoxic drugs have a therapeutic index of 1?
The therapeutic dose is the same as the toxic dose
97
What are some cellular phenotypes that allow malignancy to become resistant to treatment?
1. Rapid DNA repair
2. Rapid drug elimination
3. Drug target alteration
4. Cell death inhibition
98
Name 2 kinds of highly specific chemotherapy drugs
1. Lab synthesized monoclonal antibodies
2. Intracellular enzyme inhibitors
99
What is the goal of immune therapy?
Induce the immune system to recognize and attack tumour cells
