Brainscape's Knowledge GenomeTM

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


See full index

BS3003 > 27th Jan - Properties of Cancer Cells > Flashcards

27th Jan - Properties of Cancer Cells Flashcards

1
Q

What percentage of human cancers are of epithelial origin?

A

85%

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

Why do epithelial cells have the highest rate of cancer transformation?

A

Epithelial cells are the first exposed to any mutagens as they line external and internal surfaces

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

What are the two main components of environmental causes of cancer?

A

Infectious Agents

Lifestyle

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

Where does the main evidence for environmental causes of cancer come from?

A

Epidemiology - v. different cancer prevalence based on geographic location, and cancer rates in migrants become similar to that of the population

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

What percentage of worldwide cancer deaths is attributed to infectious agents?

A

20%

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

Give 5 examples of viruses that cause cancer in humans

A 
Epstein Barr virus
Heptatitis B virus
Human T-lymphocytic virus-1
HPV16 and HPV18
Hepatitis C virus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What cancers can be caused by the Epstein Barr Virus?

A 
Burkitt's lymphoma 
Nasopharanygeal carcinoma
Lymphoproliferative disorder
Some Hodgkin's 
Some non-hodgkins
GI lymphoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What cancers can be caused by the hepatitis B virus?

A

some Hepatocellular carcinomas

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

What cancers can be caused by the hyman T-lymphotropic virus -1?

A

Adult T-cell leukaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What cancers can be caused by HPV16 and HPV18?

A

Most cervical cancers
Most penile cancers
Angogenital cancers
Head and neck cancer

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

What cancers can be caused by the Hepatitis C virus?

A

Some hepatocellular carcinomas

Some lymphomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Name a bacteria that can cause cancer

A

Helicobacter pylori can cause gastric carcinoma

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

What are the key lifestyle factors that can cause cancer?

A

Smoking, diet, reproductive hormones, alcohol, ionising radiation and infection

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

What are tumour promoters?

A

Agents in the environment that do do not damage DNA but promote cell proliferation

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

What are tumour initiators?

A

Agents in the environment that cause DNA damage

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

Outline an experiment that shows how promoters and initiators work together to cause cancer

A

Painted initiators and promoter on mouse and monitored effects for 3 months

Paint once w/ initiator -> No effect

Multiple paintings once w/promoter –> No change

Paint once w/ initiator –> Multiple w/ promoter –> papilloma

Paint once w/ initator –> multiple w/ promoter in different region–> no change

1st initiator, then promoter –> papilloma –> stop promoter painting –> no tumour

1st initiator, then promoter –> papilloma –> keep painting w/ promoter extensively –> stop painting –> papilloma

1st initiator, then promoter –> papilloma –> paint w/ initiator –> Carcinoma

17
Q

Give examples of human tumour promoters and the cancer they promote

A 
Oestrogen --> Endometrium
Oestrogen and progesterone --> breast
Diuretics --> kidney
Hepatitis B/c virus --> liver
Bile --> small intestine
Gall stones --> gall bladder
18
Q

Give examples of chemical carcinogens

A

Polycyclic aromatic hydrocarbons
Aromatic amines
A20 dyes

19
Q

Give examples of ionizing radiation

A

Atomic particles
X-rays
UV

20
Q

What is the role of cytochrome p-150 in cancer?

A

It is a chemical carcinogen which converts PAHs into ultimate carcinogens (BPDE)

21
Q

How does UV exposure –> cancer?

A

It causes mutations by creating pyrimidine dimers

22
Q

How do you test for DNA damage?

A

the Ames test

23
Q

Outline the Ames test

A

A test for DNA damage in which you use rat liver.

Homogenize rat liver and add test compound.
Metabolically activate the compound
Add to the salmonella HIS- on HIS- media
Count the number of colonies that are now on His+

24
Q

What are the defences that protect DNA from attack by mutagens?

A

Physical shielding
Detoxification enzymes
DNA repair enzymes

25
Q

What are the main families of DNA repair enzymes?

A

Mismatch repair enzymes
Methylguanine DNA methyltransferase (MGMT)
Base excision repair (BER)
Nucleoside excision repair (NER)

26
Q

Outline mismatch repair

A

Mismatch repair, repairs incorrect base insertions

MSH2 and MSH3 flag base
Endonuclease 1 removes bases
RPA, PCNA< RFC, Pol delta or Pol epsilon replace excised DNA

27
Q

What is the role of methylguanine DNA methyltransferases in DNA repair?

A

MGMT removes methyl or ethyl adducts from the O6 position of guanine by alkylating agents e.g. ENU

28
Q

Give an example of a defect in a DNA repair gene which causes cancer

A

Familian Breast and Ovarian Cancer –> BRCA1

BS3003 (26 decks)

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