Brainscape's Knowledge GenomeTM

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


See full index

Mechanisms Of Disease > Neoplasm III > Flashcards

Neoplasm III Flashcards

1
Q

What does Retinitis (Xeroderma) Pigmentosum make people more susceptible to?

A

Increased risk of skin cancer in people exposed to UV light

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

Which gene is inherited in familial breast cancer?

A

BRCA1/BRCA2

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

What is a proto-oncogene?

A

A normal gene that can become an oncogene due to mutations or increased expression

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

How many alleles need to have an oncogene to cause a neoplasm?

A

Only one allele of a proto-oncogene needs to be mutated to cause neoplasia

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

How can proto-oncogenes be modified to create oncogenes?

A

Mutation, amplification, translocation

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

What is a tumour suppressor gene?

A

A gene that encodes proteins that suppress growth and therefore cancer

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

How many tumour suppressor genes need to be modified to create a neoplasm?

A

Both alleles of a Tumour Suppressor gene need to be mutated to produce neoplasia (Knudson’s 2-hit hypothesis).

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

What is Knudson’s 2 hit hypothesis?

A

Developed looking at retinoblastoma
2 hits needed for them to develop
Familial cancers - one hit immediately so higher risk of cancer

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

How is Ras important in the development of cancers?

A

Normally transmits growth-promoting signals to the nucleus

Mutant Ras is permanently activated resulting in continuous stimulation of cells

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

How is C-myc important in the development of cancers?

A

Binds to DNA, stimulates synthesis
Amplified (over-expressed) -Neuroblastoma, breast cancer
Translocation 8 –> 14 -Burkitt’s lymphoma

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

How is HER2 important in the development of cancers?

A

Encodes for a growth factor receptor
Amplified (over-expressed)
~25% of breast cancers
Herceptin is a competitive antagonist of HER2 receptor

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

Why is the pRB tumour suppressor gene important?

A

Passage beyond the R checkpoint at G1–>S boundary is governed by the phosphorylation of pRb.
A defect in both alleles of pRb leads to the cell escaping cell cycle control.
Retinoblastoma

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

Why is the p53 tumour suppressor gene important?

A

Approximately 50% of tumour contain p53 mutations
Gene encodes a nuclear protein, which binds to and modulates expression of genes important for cell-cycle arrest, DNA repair and Apoptosis

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

What is an initiator?

A

Carcinogenic agent

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

What is a promoter?

A

Enhance proliferations, especially in mutated cells and increase incidence of further mutations – can result in cancer

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

What does a cell need to become cancerous?

A

Initiators and promotors

17
Q

How can radiation lead to cancers?

A

single/double strand breaks
base damage.
effect depend on the quality of radiation and the dose.

18
Q

Name 2 radiations that can lead to cancer

A

UV

Ionising

19
Q

How can chemicals lead to cancers?

A

Carcinogens interact with DNA in one of a number of ways.

Some act directly, others require metabolic conversion to an active form.

20
Q

How are Polycyclic aromatic hydrocarbons produced?

A

Combustion of tobacco and fossil fuels

Hydroxylated into active form

21
Q

How can Aromatic Amines lead to cancer?

A

Hydroxylated in liver and conjugated with glucuronic acid (Phase 2 drug metabolism, non toxic)
Deconjugated to active form in urinary tract by urinary glucuronidase
Active form sits in bladder –> Bladder cancer
Common in old dye workers

22
Q

How can Alkylating Agents lead to cancer?

A

Bind directly to the DNA

An example is mustard gas

23
Q

How can Hepatitis B lead to cancer?

A

Virus causes liver cell injury –> Regenerative hyperplasia

Increased cell division gives increased risk of genetic changes

24
Q

How can Epstein Barr lead to cancer?

A

Infects epithelial cells or oropharynx and B cells
Viral genes dysregulate normal proliferative and survival signals
Sets the stage for acquisition of mutations

25
Q

How can the Human Papilloma lead to cancer?

A

HPV genes disrupt normal cell cycle

Viral genes incorporated into host cell genome, driving proliferation

26
Q

What does Asbestos exposure lead to?

A

Malignant mesothelioma

lung cancer

27
Q

What does Aflatoxins exposure lead to?

A

Hepatocellular carcinoma

28
Q

What does Schistosoma exposure lead to?

A

Bladder cancer

29
Q

What does Helicobacter exposure lead to?

A

Gastric cancer

Lymphoma

30
Q

Which cancers can hormones lead to?

A

Androgens and hepatocellular carcinoma

31
Q

What conditions can predispose to cancer?

A

Cirrhosis
Adenoma of colon/rectum (Adenocarcinoma)
Ulcerative colitis (DNA damage and microstatic instability)

Mechanisms Of Disease (11 decks)

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