Brainscape's Knowledge GenomeTM

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


See full index

Cancer Biology > Chemoprevention > Flashcards

Chemoprevention Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

In people under 85, what is the leading cause of death?

A

cancer

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

In people over 85, what is the leading cause of death?

A

Cardiovascular disease

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

Cancer death rates have decreased slightly, what is this a result of?

A

The reduction in lung cancer due to anti-smoking campaigns

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

How do hereditary facts commonly predispose people to cancer?

A

Initiating mutation to all stem cells

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

How can phase I enzyme induce neoplasia?

A

They produce reactive electrophiles which instead of being conjugated by phase II enzymes, they cause damage to macromolecules such as DNA and cause neoplasia

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

How can you stop phase I enzymes inducing neoplasia?

A

By the induction of phase II and phase III enzymes so the reactive electrophiles are conjugated by phase II enzymes and then removed by phase III drugs by drug efflux

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

What is glutathione?

A

An antioxidant

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

What is the role of glutathione transferases?

A

Conjugates the electophiles with glutathiones and helps with excretion

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

Where is glutatione present and how much is there?

A

Present in every cell in the body

Have as much as ATP

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

What is the purpose of the Quinone Reductase assay?

A

To detect the enzyme activity in a cell

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

What vegetable family has the highest inducer activity?

A

Cruciferous

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

Give examples of cruciferous vegetables

A 
Arabidopsis 
Cabbage
Broccoli 
Kale 
Cauliflower 
Brussel sprouts 
Rocket 
Watercress
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What do cruciferous vegetables contain?

A

Unique phytochemicals - Glucosinolates

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

What determines the diversity of glucosinolates?

A

The R group

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

How does the degradation of glucosinolates occur?

A

They are made in the plant and are stable and inert -> when the plant is damage it releases myrosinase -> myrosinase hydrolyses glucosinolate -> end product

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

What is the most reactive end product of glucosinolate degradation?

A

Isothiocyanate

17
Q

What does benzyl isothocyanate inhibit?

A

DMBA-induced mammory tumour formation in Sprague-Dawley rats
Formation of neoplasms of the forestomach and pulmonary adenomas in ICR/Ha mice

18
Q

How much do cruciferous vegetables lower the risk of colon cancer?

A

51%

19
Q

How much do cruciferous vegetables lower the risk of prostate?

A

67%

20
Q

how is sulforphane made?

A

Glucoraphanin (glucosinolate) -> Unstable Aglucon -> Sulforaphane

21
Q

What are the cytoprotective actions of sulforaphane?

A

Induces phase II enzymes and elevates gluathione levels
Inhibits tumour development in animal models
Causes cell cycle arrest and apoptosis
Week inhibitor of CYP2E1
Not mutagenic
Protects against oxidants through induction of phase II enzymes and glutathione (indirect antioxidant)

22
Q

How does sulforaphane induce an indirect antioxidant effect?

A

Cul3 is bound to Keap1 -> Keap1 has a highly reactive cysteine on its SH2 -> chemically modified by sulforaphane -> loses its activity and therefore Nrf2 is not degraded

23
Q

What is the role of Nrf2?

A

When it is not degraded, it moves into the nucleus -> binds to the promoter (ARE) as a heterodimer with sMaf -> production of cytoprotective gees

24
Q

What is the rate limiting factor in the Nrf2 process and why?

A

Nrf2 since it is less abundant than sMaf

25
Q

Apart from Keap1, what does sulforaphane inhibit? And what do they all induce?

A

NF-kappaB
STAT3
MIF (macrophage migration inhibitory factor)
Inflammation and cell growth

26
Q

When Keap1 is inhibited, what does it induce?

A

Redox balance

Resolution of inflammation

27
Q

What cancers is sulforaphane cytoprotective in?

A 
Breast 
Lung 
Skin 
CRC 
Stomach
28
Q

What can topical addition of sulforaphane do to nude mice?

A

Stop them getting skin cancer

29
Q

Apart from lung cancer, what else is tobacco smoke associated with?

A

Bladder cancer

30
Q

What can you measure sulforaphane metabolites in?

A

urine

31
Q

What does resveratrol reduce?

A

Carrageenan-induced inflammation in rats
Skin cancer formation in mice
Inhibits adenoma development in APCmin mice

32
Q

What is resveratrol found in?

A

Red grapes

33
Q

At what dose is resveratrol better at inhibiting adenoma development in APCmin mice?

A

Lower doses

34
Q

In terms of lung cancer, what do antioxidants do? And why?

A

Accelerate lung cancer progression in mice

Appears to lower Nrf2 expression and therefore lowers cytoprotection

Cancer Biology (13 decks)

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