Carginogensis and cancer epidemiology

Question 1

malignant environmental factors

Answer 1

• smoking
• alcohol
• obesity

Question 2

chemical cargiongenesis stages

Answer 2

initiation
promotion
latent period

Question 3

initiation in chemical cargiongnesis

Answer 3

permanent DAN damage
e.g. change in bases
cell is primed to be stimulated more by something which may increase proliferation

Question 4

promotion in Chemical carginoensis

Answer 4

may be reversile

promotes proliferation

Question 5

latent period chemical cargiongensis

Answer 5

time from initiation to clinical tumour

Question 6

procarcinogen

Answer 6

often metabolised to ultimate carcinogen

Question 7

co carginogen

Answer 7

not carcinogen them selves

increase effect of carcinogen

Question 8

direct chemical carginogens

Answer 8

tumour arises at site of carcinogen application

Question 9

indirect chemical carcinogen

Answer 9

tumor arises at different site from carcinogen application

Question 10

physical carcinogenesis and what it does/examples

Answer 10

ionising radiation
damaged DNA causing mutations
- x rays, radium , radon ,atomic bomb

Question 11

radiation sensitivity - most to least senstitbe tissues

Answer 11

• embryonic tissues
• haematopoietic organs
• gonads
• epidermis
• intestinal mucous membrane (variable)
• connective tissue
• muscle tissue and nerve tissue

Question 12

UV light

Answer 12

damages DNA

skin (squamous cell carcinoma, basal cell car..)

Question 13

xeroderma pigmentosum

Answer 13

patients with this have a faulty system which fixes the damage by UV light

Question 14

viral carcinogenesis types

Answer 14

1) DNA viruses
- more common
- viral DNA inserted into host DNA
2) RNA viruses
- more complex, has to be reverse transcribed then inserted
- may contain oncogenes (genes that once are active become proteins which can cause the cells to divide or move more)

Question 15

what can HPV cause

Answer 15

cervical carnoma

oropharynx carnimoa

Question 16

what does HPV virus do

Answer 16

Viral proteins binds to and inactivates the tumour suppressors and p53 and Rb

• HPV genome does not have oncogenes that switch things on, it has proteins that switch things odd
• Cell cycle control no longer occurs, cells can divide rapidly

Question 17

other influences on carcinoma development

Answer 17

Often act as promoters

1) Hormones
- breast cancer, hormonal dependence, ovary adrenal
- Prostate cancer, testosterone influence
2) Drugs
- including alcohol
3) inflammation
- chronic inflammation especially increases the risk of cancer

Question 18

how can cancer develop (3 ways)

Answer 18

• denovo(just arises)
• via benign
• via premalignant lesion( change in tissue increases succeptibiktou to becoming malignant)

Question 19

premaliganancy

Answer 19

Some of the changes in cells and tissue architecture are seen before invasion occurs
this disorganisation of the tissue is called Dysplasia

Question 20

disorganisation of tissue

Answer 20

dysplasia