Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Yr 2 - IBMS > Biology of Cancer > Flashcards

Biology of Cancer Flashcards

1
Q

Define Cancer

A

a group of diseases characterised by unregulated cell growth followed by the invasion and spread of cells from the site of origin to other sites in the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What % of Cancers arise in Epithelial Cells? Why

A

85%

it is a site of constant proliferation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a Cancer of Epithelial Origin Called?

A

Carcinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is a Cancer of Mesodermal Tissues Called?

A

Sarcomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a Cancer of Glandular Tissues Called?

A

Adenocarcinomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define Senescent

A

cell no longer replicates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

At what point do Cells become Senescent

A
  • at the end of each chromosome = telomere
    a telomere is a repeated sequence of DNA
  • telomere shortens with every round of replication
  • cell stops dividing when telomere reaches a certain length
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 6 Hallmarks of Cancer? Add 2 Extra Hallmarks

A
  1. Sustaining Proliferative Signalling
  2. Evading Growth Suppressors
  3. Activate Invasion and Metasis
  4. Enabling Replicative Immortality
  5. Induing Angiogenesis
  6. Resisting Cell Death
  7. Deregulating Cellular Energetics
  8. Avoiding Immune Destruction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Give 2 Enabling Characterstics of Cancer which Enhances the Hallmarks

A
  1. Genome Instability and Mutation
    - by causing dna to be faulty, it causes genome instability, passes down onto daughter cells
  2. Tumour Promoting Inflammation
    - all malignant cells contain inflammatory cells
    - can release reactive species, growth factors and enzymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Give 6 Environmental Factors Causing Cancer

A

smoking
obesity
radiation
diet
alcohol use
chemicals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is the Epidemiology of Nutrition and Cancer Found?

A

the links between cancer, nutrition and migration

  • someone moves from low risk to high risk areas
  • new local diets are adopted
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What 7 Cancers can Unhealthy Diets Lead to?

A

Oral and Upper Throat
Larynx
Oesophagus
Lung
Stomach
Bowel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the 3 Dietary Cancer Causative Factors?

A
  1. Genotoxic agents in food - dietary carcinogenics
  2. Lack of specific nutrients
  3. Public health Issues - alcohol and obesity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Give 3 Genotoxic Contaminants and Where they are found in Food

A

Aflatoxin and Fumonsin B
- mold growing on poorly stored food

Heterocyclic Amines
- high heat cooked meats like BBQ

Polychlorinated Biphenols
- occur in farmed salmons
- in a process called biomagnification, goes through the food chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which Deficient Nutrient Increases the Risk for Colorectal Cancer

A

Vitamin B9 (Folate)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does Folate Deficiency Increase risk for Cancer? (6)

A
  • hypomethylation of DNA
  • inhibits production of dTMP
    (deoxyythymidine monophosphate)

= imbalance of nucleotide availability
- Uracil incorporated into DNA due to no Thymine
- DNA repair to remove u and place with T but makes DNA breaks

= increased frequency of mutations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What 4 Cancers are Alcohol a Risk Factor?

A

oral, breast, colon and liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does Alcohol Increase the Risk for Cancer?

A

Ethanol is metabolised into Acetylaldehyde by endogenous alcohol dehydrogenase

  • binds to DNA
    = DNA adducts - have a cancer chemical bound to it
  • causes mutations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

After Drinking Alcohol, How much more Acetylaldehyde is Present in the Saliva?

A

100x

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 6 Common Cancer Tissues from Which Obesity Has a High Risk association

A
  • breast
  • colorectal
  • endometrium
  • oesophagus
  • kidney
  • liver
  • multiple myeloma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the Proposed Mechanisms for How Obesity Leads to Cancer?

A

1) endocrine organ, secretes hormones like oestrogen = links to breast cancer

2) adipose increases storage for carcinogens

3) induces a chronic inflam response, more IL6 and TNFa

4) shift in gut microbiome, increased production of deoxycholic acid bacterial metabolism, reaches liver, DNA damage

22
Q

What are Antioxidants?

A

compounds that significantly inhibit or delay the damaging action of ROS, may have a protective effect against cancer

23
Q

Give 4 Phytochemical Antioxidants

A

Vitamin C
Isoprenoids
Flavonoids
Organosulfur Compounds

= plant derived

24
Q

What is Isothiocynate?

A

a micronutrient from vegetables that can affect gene expression

25
Q

What Cancers does Increased Consumption of Red and Processed Meat Link to?

A

Gastroesophageal groups

26
Q

Why does Increased Consumption of Red/Processed Meat Link to Cancer?

A
  • high levels of haem in red meat
  • high levels of nitrate/nitrite preservatives in processed

can be converted into carcinogenic chemicals
- N-nitroso compounds (NOCs)

27
Q

What are the 2 Major Types of Mutated Genes Contributing to Carcinogenesis?

A

Oncogenes
Tumour Suppressor Genes

28
Q

Define an Oncogene

A

product of the mutated gene that is increased in high quantities, therefore acts in a dominant fashion, a positive factor

29
Q

What are Unmutated Forms of Oncogenes?

A

proto-oncogenes

30
Q

What is the Function of a Tumour Suppressor Gene?

A

inhibiting growth and tumour formation

mutation = loss of function, allows growth

usually recessive, a negative factor

31
Q

What are Germline mutations?

A

inherited cancer genes

32
Q

What are Somatic Mutations?

A

spontaneous cancer genes

33
Q

What are 4 Common Protoco-Oncogenes?

A

growth factors
components of signal transduction cascades
nuclear DNA binding
DNA repair

34
Q

How is Cell Division Initiated?

A
  • signalling molecule binds to signal receptor
  • signal passed through the cell via signal cascade
  • protein are phosphorylated and activated by protein kinase
  • phosphorylated proteins activate transcription factor
35
Q

How can Mutation Affect Proto-oncogenes?

A
  • increased growth factors
  • increased signal receptors
  • increased protein kinases
  • increased transcription factors
    ==== more division
36
Q

What is a Tyrosine Kinase Receptor and how does it work?

A

a receptor on the extracellular surface of the cell

  1. substrate binds to receptor in its inactive form
  2. kinase activity is stimulated
  3. tyrosines on the in the cystol are phosphorylated
  4. intracellular proteine bind to phospho-tyrosin docking sites
37
Q

What are 2 Examples of Mutated TKRs, linked to Cancer?

A

FGFR - Fibroblast growth factor receptor
ERBB2

38
Q

What Gene Helps Control Cell Division?

A

CDK4, a cyclin dependent kinase

39
Q

What Happens to a Mutated CDK4?

A

altered CDK4 protein
= abnormally overreactive
= fast division, tumour

40
Q

Name a Mutated Transcription Factor

A

myc gene

41
Q

How does p53 Mutate and then Link to Cancer?

A
  • mutations on chromosome 17
  • loss of heterozygosity at the short arm
  • tumour of lung, colon and breast
  • mutations on p53 locus
  • cancers of lung, colon, breast and liver
42
Q

What can p53 be Activated by?

A

Telomere shortening
DNA damage
hypoxia
hyper proliferative signals

43
Q

What 3 things can p53 lead to?

A

Senescene
Apoptosis
Cell-Cycle Arrest

44
Q

How does DNA Damage Activate p53, and lead to cell death?

A
  • phosphorylated p53 can no longer bind to protein Mdm2
  • not sent to the proteasome for next steps
  • begins to accumulate
  • induces transcription of several genes
  • activation of p21 gene
  • transcription and translation of p21 protein
  • p21 binds and inhibits cyclin-dependent kinases
  • cells dont progress to s phase of cell cycle
  • doesn’t complete cell cycle = apoptosis
45
Q

Which 4 Processes allow a Proto-oncogene Form an Oncogene?

A
  1. Translocation
  2. Gene Amplification
  3. Point Mutation within control element
    = excess growth stimulating protein
  4. Point mutation within the gene
    = hyperactive or degradation resistant protein
46
Q

What are 3 Functions of Macrophages in Inflammation?

A

release pro inflam cytokines
ROS and RNS release
suppression of anti-tumour immune response

47
Q

How do Pro Inflam Cytokines Link to Gene Regulation?

A

pro inflam cytokines induced NF-kB
- NF-kB regulates genes
- drive cell cycle
- cell survival
- anti-apoptotic

48
Q

What are the 2 Types of Tumour Viruses?

A

DNA Genome
RNA Genome (retrovirus)

49
Q

Describe the Features on How Cancer Develops in the Benign Stage NAHAKATAPCI

A

Hyperproliferation
Small to Larger Polyps

  1. normal epithelial
  2. loss of APC
  3. hyper plastic epithelium
  4. early adenoma
  5. activation of K-ras
  6. intermediate adenoma
  7. loss of 18q TSG
  8. late adenoma
50
Q

Describe the Development of Cancer in the Malignant Stage NAHAKATAPCI

A

Abnormal cell growth and severe dsyplasia
Adenocarcinoma
Cancer

  1. late adenoma
  2. loss of p53
  3. carcinoma
  4. invasion and metastasis
51
Q

Describe the Steps for Metastasis

A
  1. primary tumour formation
  2. localised invasion
  3. intravasation - interaction with blood components
  4. transport through blood circulation
  5. arrest in micro vessels of various organisms
  6. extravasation
  7. formation of micro metastasis
  8. colonisation - formation of macrometasasis

Yr 2 - IBMS (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions