Cancer - What is Cancer & Development Flashcards

Aoife

You may prefer our related Brainscape-certified flashcards:
1
Q

Cancer Terminology

Proliferation

A

The process of cell growth and cell division leading to the expansion of the cell population

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

Cancer Terminology

Differentiation

A

When early cells (for example stem cells or progenitor cells) give rise to specialised cells

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

Carcinogenesis

What is carcinogenesis

A

The process by which cancers are generated

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

Carcinogenesis

What does carcinogenesis result from

A

An accumulation of errors in vital regulatory pathways

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

Carcinogenesis

What is the core feature of cancer

A

Uncontrolled proliferation (cell division and expansion)

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

Carcinogenesis

What are normal cells subjected to that control cell growth and what happens to this during carcinogenesis

A

Internal and external inhibitory signals that control cell growth and this control is lost in carcinogenesis

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

Carcinogenesis

What is as important as increased proliferation for carcinogenesis and why

A

Decreased rate of cell death -> the longer a cell lives, the more likely for genetic errors to occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Carcinogenesis

What are essential for a tumour to survive and what is the name for the growth of these

A

New blood vessels are essential for a tumour to survive. The growth of new blood vessels is called angiogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Carcinogenesis

General carcinogenesis description

A
  • carcinogenesis is a multi step mechanism
  • results from an accumulation of errors in vital regulatory pathways
  • uncontrolled proliferation (cell division and expansion) is the core feature of cancer
  • normal cells are subject to internal and external inhibitory signals that control cell growth
  • this control is lost during carcinogenesis
  • cells multiply and acquire additional changes that give it a survival advantage
  • these changes generate billions of cells
  • decreased rate of cell death as important for carcinogenesis as increased proliferation as the longer a cell is alive, the more likely for genetic errors that generate cancer to occur
  • new blood vessels are essential for tumour survival (angiogenesis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what cancers are characterised with onset in childhood (2)

A
  1. Cancer of the eye
  2. Certain leukaemias
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Lifestyle influences on cancer (6)

A
  1. Occupational cancers -> lab work, construction, radiographers etc…
  2. Free radical generation
  3. Carcinogens in cigarettes
  4. Mutations in repressor genes and oncogenes
  5. Inherited predisposition
  6. Diet
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Cancer & genes

Cancers are generated by what (in terms of genes)

A

Changes in genes that have a role in controlling cell growth

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

Cancer & genes

What do gene changes in cancer cause

A

Changes in cell signalling pathways with the end result being uncontrolled growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Cancer & genes

Definition of a repressor gene

A

A gene whose protein product inhibits a cell function

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

Cancer & genes

Definition of an Oncogene

A

A genes whose protein product contributes to carginogenesis

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

Cancer & genes

Definition of a Proto-oncogene

A

A gene present in normal cells that can as a result of a mutation become an oncogene

17
Q

The 2 strategies that cancer cells use to make energy from sugar in the tumour environment

A
  1. Aerobic respiration: cells use both sugar molecules and oxygen to make energy
  2. Anaerobic respiration: cells that are anaerobic use sugars to make energy -> formation of toxic lactic acid which kills nearby healthy cells, making room for more cancer cells
18
Q

5 cancer risk factors

A
  1. Smoking
  2. Diet
  3. Sex hormones
  4. Increasing age
  5. Family history
19
Q

What is the most common cancer in Ireland and why is it so prevalent

A

Skin cancer (26%)
We have a thinner layer of the ozone layer

20
Q

Cancer risk factors

Smoking as a risk factor for cancer

A
  • USA: 30% of cancer deaths due to smoking
  • Non smoker who lives w a smoker has a 30% higher risk of dying from lung cancer than when living w a non smoker
  • Smoking linked to increase in lung, mouth, oesophagus, pharynx, kidney, bladder cancer
  • Over 40 potential carvinogens isolated from tobacco
  • 20 year gap between increased tobacco consumption and lung cancer changes
21
Q

Cancer risk factors

Free radicals as a risk factor for cancer

A
  • They are ions/ molecules with unpaired electrons
  • They are highly reactive and likely to take part in chemical rxns
  • Superoxide and hydroxyl radicals can partake in unwanted side rxns, causing cell damage
  • Many cancers thought to be a result of reactions between free radicals and DNA, resulting in mutations that can affect the cell cycle and lead to malignancy
22
Q

Cancer risk factors

How does the body minimise damage by free radicals

A
  • As free radicals essential for life, body has mechanisms to minimise the cell damage done by them and to repair cell damgage that does occur
  • The enzyme, superoxidase dismutase, minimises free radical induced cell damage and repairs some of the damage
  • Antioxidants neutralise free radicals -> vitamins A, C, E are antioxidants
23
Q

Cancer risk factors

Diet as a risk factor for cancer

A
  • Fruit and veg (contain antioxidants) are protective against cancers
  • Eastern diet containing many plant products contains many beneficial ingredients
  • Western diet, opposite effect
  • Mediterranean diet: good as high in fruit and veg, red wine (phenols), complex carbohydrates and low saturated fat content
24
Q

Cancer risk factors

Diet - Fruit and Veg

A
  • High fruit and veg consumption associated w decreased risk of many cancers
  • High fruit and veg linked to low animal fat consumption
  • Carotenoids, found in many plants, are: rich in antioxidants, precursors of Vit A which hinders cellular proliferation
  • Plant derived vitamins, A,C,E have antioxidant properties
25
Q

Cancer risk factors

In what ways does fibre in the diet have a protective effect (3)

A
  1. Fibre may inactivate carcinogens
  2. Fibre may alter profile of gut micro flora
  3. High fibre diet is often one low in fat
26
Q

Cancer risk factors

Diet: In terms of fat and meat consumption, what increases the risk of cancer

A
  • A high total fat consumption especially of animal origin increases cancer risks in many sites
  • Animal fat high in saturated fatty acids and cholesterol, increases risk of cancer
27
Q

Cancer risk factors

Obesity: Why has obesity been identified as a risk factor for breast and uterine cancers

A

Due to its effect on the production of the female sex hormone, oestradiol. Fat cells can synthesise the production of the mitogenic steroid oestradiol, that triggers hyper proliferation.

28
Q

Cancer risk factors

Diet: a high salt intake inreases the risk of what

A

Stomach cancer

29
Q

Cancer risk factors

Diet: What does a high alcohol consumption increase the risk of

A
  • The risk of breast, colon, liver and upper digestive tract cancers
30
Q

Cancer risk factors

Diet: What kind of effect do smoking and alcohol consumption have

A

A synergistic effect in cancers of the mouth, oesophagus and larynx. Synergistic = their combined effect is greater than if only one of them occured

31
Q

Cancer risk factors

Sex hormones: How does diet affect the level of testosterone

A

A low fat diet decreases the level of testosterone and is associated with a low prostate cancer risk

32
Q

Cancer risk factors

Sex hormones: How does diet affect the level of oestrogen

A

Obesity in women increases oestrogen synthesis which increases growth factors that stimulate proliferation of cells and particularly increasing risk of breast cancer

33
Q

Cancer risk factors

What do male and female hormones do to their target cells

A

Influence proliferation of their respective cancer cells

34
Q

Cancer risk factors

Is there a genetic association with cancer

A

There is with some cancers, but in none of them does it account for more than 10% of cases

35
Q

Cancer risk factors

What is a major trigger for skin cancer such as melanoma

A

UV light (from sun and tanning equipment)

36
Q

Cancer risk factors

The 4 viruses that cause human cancer and the cancers they cause

A
  1. Hep B&C -> liver
  2. Human Papilloma Virus (HPV) -> cervix
  3. Human Immunodeficiency -> sarcoma (cancer in connective tissues)
  4. Human T-cell Lymphotrophic -> leukaemia