Unit 22

Question 1

Cancer:

What are the top 3 leading causes of death in Canada for males?

Answer 1

1. Lung
2. prostate
3. colon and rectum

Question 2

Cancer:

What are the top 3 leading causes of death in Canada for females?

Answer 2

1. lung
2. breats
3. colon and rectum

Question 3

What are the 4 steps of cancer?

Answer 3

1. intitiation
2. promotion
3. progression
4. metastasis

Question 4

What is initiation?

Answer 4

carcinogen causes permenant genetic change in a cell which carries the mutation until death

Question 5

Cancer

Explain promotion

Answer 5

Compounds cause the initiated cells to dived and accumulate - large number of daughter cells with the mutation (benign tumors)

Question 6

cancer

Explain progression.

Answer 6

benign tumor to neoplasm, cells can undergo further mutations with metastatic potential

Question 7

cancer

Explain metastasis

Answer 7

invade surrounding tissues and/or spread

Question 8

What factors affect cancer development?

Answer 8

1. genetic factors - affects risk
2. immune factors - inneffective immune system may not recognize tumor as foreign (age and immunosuprressive drugs and viral infection decreases immune function)
3. Environmental factors - UV light, smoking, toxic environment/contaminants
4. dietary factors

Question 9

Dietary factors:

What are initiators? Give some examples

Answer 9

Carcinogens
- pesticides at high doses
- nitrosamines, which occur naturally or are formed during processing

Question 10

How are nitrosamines formed? What type of cancer are they linked to?

Answer 10

• alcohol (beer and scotch)
• processed meats – in the stomach, nitrates (preservative) can combine with amines to form nitrosamines\

linked to:
- stomach, esophagus, liver and bladder cancer

Question 11

What are some the different class one carcinogens?

Answer 11

Group 1: carcinogenic to humans
- processed meats
Group 2A: probably carcinogenic to humans
- red meat
Group 2B: possible carcinogenic to humans
Group 3: unclassifiable as to carcinogenicity to humans
Group 4: probably not carcinogenic to humans

Question 12

Dietary factors:

What are promoters? What is a main promotor

Answer 12

accelerate tumor development

mainly linked to fats
- excess dietary fat
- omega-6 fatty acids
- fat used to deep fry food for too long
- old fat (oxidized fat – free radicals)

Question 13

dietary factors:

What are antipromoters?

Answer 13

reduce cancer risk
- high fruits and vegatbles
- fiber protective aganst colon cancer
- phytochemicals - cruciferous vegetables

Question 14

How can you redcue cancer risk?

Answer 14

slect foods low in salt and fat
prepare foods safely
- don’t eat charred foot (eat food cooked in direct flame only occasionally) – causes chamicals that damage DNA

Question 15

When do HCAs form?

Answer 15

when amino acis. sugars and creatine in muscle meats react at high temperatures

Question 16

When do PAHs form?

Answer 16

when fat or juices from meat grilled over a heated surface or open fire drip onto the surface or fire and cause flames and smokes. smoke contains PAHs and that sticks to surface of meat

also formed during smoking of food

Question 17

Tips for cooking meat to reduce cancer risk.

Answer 17

• don’t burn food and remove charred portions
• marinating meats
• trim the fat (fit dripping produces harmful smoke)
• lower the temperature – low and slow
• indirect heat methods like stewing, steaming or poaching