Unit 3 - Cancerous Cells + Adrenaline Pathway

Question 1

How are cancer cells created?

Answer 1

Through uncontrollable and rapid cell division.

• creates error allowing for cells to have mixed chromosomal levels, and cells will not have the correct number of chromosomes –> mutations

Question 2

What is the function of the EGF and MAPK Pathway?

Answer 2

Stimulates Cell Division

1. Triggers cell replication
2. Triggers growth of the cell
3. Shuts down mutated cells and forces it into cell death, decreasing cancer cells

Question 3

What does the Receptor Tyrosine Kinase (RTK) do?

Answer 3

EGF Receptor that activates the Ras and MAP Kinase pathway

Question 4

What does GEF do?

Answer 4

• Activates RAS
• Replaces GDP with GTP

Question 5

What does GAP do?

Answer 5

• Deactivates RAS
• turns RAS GTPase (self regulating aspect)

Question 5

How does RAS Self Regulate and turns itself off?

Answer 5

Through using GTPase

–> an enzyme which removes a Phosphate group and changes the GTP to GDP and it is no longer active

Question 6

What is the Her 2?

Answer 6

• A membrane tyrosine kinase and has potential to
  cause cancer
• A certain Receptor Protein
• “Her 2 Receptors”

Question 6

What happens if a person is Her 2+

Answer 6

• Causes more aggressive cancer
• Easier to treat because there is a way to pinpoint
  the issue

Activates cell division when not signaled too
–> cause rapid and uncontrollable cell division

Question 6

What does it mean if the patient is Her 2-?

Answer 6

• Cancer not as aggressive
• Harder to treat since there is not a direct issue
• Do not have an abnormal amount of Her 2 proteins
• Her 2 proteins are not the issue that cause cancer
• cancer is caused by other issues

Question 7

What happens if patients are given drugs that target different parts of the mutated pathway?

Answer 7

Does NOT remove the cancer

But it helps increase life span

Question 8

Where are the checkpoints in mitosis?

Answer 8

G1 G2 and G0

Question 9

What is the order of the RAS and MAPK pathway?

Answer 9

RAS –> RAF –> MEK –> MAPK / ERK

Question 10

What does EGF (Epidermal Growth Factor) signals cause?

Answer 10

They activate cell division pathways

Question 11

Explain the EGF and MAPK pathway

Answer 11

1. A EGF Factor comes in
2. The EGF Receptor (Tyronise Kinase Receptor) is activated
3. Receptor activates GEF
4. GEF turns Ras On
5. Ras touches RAF and activates it
6. GAP activates GTPase turning RAS off
7. RAF Phosphorylates MEK
8. MEK phosphorylates ERK
9. ERK activates transcription factors

Question 12

What does the Adrenaline Pathway do?

Answer 12

Activated by Epinepherine which causes a fight or flight response

Question 13

What are G coupled receptors

Answer 13

Receptor types which have a Gprotein complex attached to the receptor, that when the receptor is activated it will let go of the G protein and it can activate its cascade

Question 14

In the adrenaline pathway how does the receptor activate the g protein alpha to activate the effector

Answer 14

through exchanging GDP to GTP

Question 15

What happens to the g protein once activated

Answer 15

it lets go of the gamma and beta parts of the g protein and activates the effector = Adenylyl Cyclase

Question 16

What does the Adenylyl Cyclase effector do?

Answer 16

• once g protein alpha activates the Adenylyl Cyclase
• takes in ATP from donating mitochondria
• Converts to cAMP = removes 2 Phosphate groups
• cAMP binds to the regulatory subunit –> once binded it can release the Protein Kinase “A”
• PKA then activates targeted proteins

Question 17

What is a second messenger protein

Answer 17

It is an activated proteins which relay a message sent by extracellular signals