Cancer Chemoprevention

Question 1

Cure is better than prevention, true or false?

Answer 1

False, prevention is better than cure

Question 2

What percentage of patients can be cured of cancer?

Answer 2

~50%

Question 3

Once cancer has occurred, what can be the downsides to treatment?

Answer 3

It may be unpleasant, ineffective and extremely expensive

Question 4

Who do cancer treatments impact?

Answer 4

Patients
Families
Society

Question 5

Give an example of how cancer cells can induce angiogenesis

Answer 5

Through the production of VEGF

Question 6

Give an example of how cancer cells can activate invasion and metastasis

Answer 6

Though the inactivation of E-cadherin

Question 7

Give an example of how cancer cells can cause tumour-promoting inflammation

Answer 7

Through COX overexpression

Question 8

Give an example of how cancer cells can enable replicative immortality

Answer 8

By turning on telomerase

Question 9

Give an example of how cancer cells can avoid immune destruction

Answer 9

By infiltrating tumour-promoting inflammatory cells

Question 10

Give an example of how cancer cells can evade growth suppressors

Answer 10

Through the loss of the Rb suppresssor

Question 11

Give an example of how cancer cells can sustain proliferative signalling

Answer 11

Through the activation of Ras oncogenes

Question 12

Give an example of how cancer cells can deregulate cellular energetics

Answer 12

By increasing glycolysis

Question 13

Give an example of how cancer cells can resist cell death

Answer 13

Through the production of IGF survival factors

Question 14

Give an example of how cancer cells can acquire genomic instability and mutations

Answer 14

Through an increase in mutation rate

Question 15

What are the 4 biggest causes of cancer?

Answer 15

Tobacco
Diet
Overweight and obesity
Alcohol

Question 16

What are the eight recommendations to decrease cancer risk?

Answer 16

1. Be as lean as possible without becoming underweight
2. Be physically active for at least 30 minutes every day
3. Avoid sugary drinks and limit consumption of energy-dense foods (particularly process foods high in sugar, or low in fibre, or high in fat)
4. Eat more variety of vegetables, fruits, wholegrains and pulses such as beans
5. Limit consumption of red meats and avoid processed meats
6. If consumed at all, limit alcoholic drinks to 2 for men and 1 for women a day
7. Limit consumption of salty foods and food processed with salt (sodium)
8. Don’t use supplements to protect against cancer

Question 17

Define chemoprevention

Answer 17

Use of natural or synthetic compounds to reverse, suppress, prevent or delay carcinogenic progression to invasive cancer

Question 18

What should the ideal chemopreventative agent have?

Answer 18

High efficacy
No or low toxicity
Known mechanism(s)
Acceptance by humans
Oral formulation
Low cost

Question 19

Define blocking agents

Answer 19

Compounds which inhibit carcinogenesis by preventing carcinogens from being generated or from reaching, or reacting with, critical target sites in tissues

Question 20

Define suppressing agents

Answer 20

Compounds which act after carcinogenic exposure by suppressing the expression of neoplasia

Question 21

What would the use of surrogate endpoint biomarkers allow?

Answer 21

Smaller trials, quicker assessment of efficacy without waiting for tumours

Question 22

What would the use of surrogate endpoint biomarkers require?

Answer 22

A detailed understanding of the cancer process in any given tissue
A detailed understanding of the mechanism of action of the chemopreventive agent

Question 23

What percentage of high risk women saw a reduction in breast cancer after treatment with tamoxifen?

Answer 23

38%

Question 24

Tamoxifen has no real adverse effects, true or false?

Answer 24

False, it can have serious adverse effects including endometrial cancer and venous thromboembolic events

Question 25

During the development of cancers, at what stages are there opportunities for prevention?

Answer 25

Between a cell changing from normal to hyperproliferating
Between an adenomatous polyp changing from small to large
Between a pre-cancerous polyp to an adenocarcinoma