Carla - Receptors and Disease

Question 1

Give some ways cell communication can go wrong
(3)

Answer 1

Cell fails to send out a signal at the proper time

A signal doesn’t reach its target

A target cell does not respond to a signal or a cell responds even though it hasn’t received a signal

Question 2

Give an example of a disease caused be a lose of a signal

Answer 2

Type 1 diabetes

Question 3

Give an example of a disease caused a signal not being able to reach it’s target

Answer 3

Multiple sclerosis

Question 4

Give an example of a disease caused by a target ignoring a signal

Answer 4

Type 2 diabetes

Question 5

Give an example of a disease caused by multiple breakdowns in signalling

Answer 5

Cancers

Strokes

Alzheimers

Chronic and complex diseases

Question 6

What are the two types of receptor linked diseases?

Answer 6

Congenital

Acquried

Question 7

What are the two types of receptor linked diseases?

Answer 7

Congenital

Acquired

Question 8

What causes familial hypercholesteremia

Answer 8

A defect in an LDL receptor

Question 9

What is familial hypercholesteremia (FH)

Answer 9

Significantly elevated low-density lipoprotein cholesterol

Early onset

20x higher risk of coronary artery disease

Question 10

Give an example of a congenital receptor disease

Answer 10

Myasthenia gravis

Question 11

What is myasthenia gravis?

Answer 11

A disease of the postsynaptic neuromuscular junction (NMJ) where nicotinic acetylcholine (ACh) receptors (ACHRs) are targeted by antibodies

Question 12

What are the symptoms of myasthenia gravis?

Answer 12

Weakness and rapid fatigue of any of the muscles under voluntary control

Question 13

In general what happens to the receptor in myasthenia gravis?

Answer 13

Loss of receptor function - the message is not heard

Question 14

What do practitioners have to consider when working with myasthenia gravis patients?

Answer 14

They are extremely sensitive to anaesthetic

Question 15

What happens in acquired receptor disease?

Answer 15

Good receptors turn bad

Question 16

Give an example of a receptor that can be affected by acquired receptor diseases?

Answer 16

Receptor tyrosine kinases

Question 17

What different alterations can be made to receptor tyrosine kinases?
(3)

Answer 17

Amplification

Overexpression

Somatic mutation resulting in increased receptor signalling

Question 18

List some diseases caused by RTK mutations

Answer 18

Dwarfism

Craniosynostosis

Heritable cancer susceptibility

Venous malformation

Piebaldism

Question 19

What happens when there is a gain of function mutation of a receptor tyrosine kinase?

Answer 19

Result in constitutive receptor activation

Question 20

What happens when there is a loss of function mutation of a receptor tyrosine kinase?

Answer 20

Result in non-functional or dominant negative receptors

Question 21

Write a note on receptors in oncogenesis

Answer 21

Cancer often caused by receptors involved in growth, proliferation and differentiation

e.g. breast cancer can have receptors which are hormone-positive

Question 22

What are the three types of hormone positive breast cancer?

Answer 22

ER positive
PR positive
HER2 positive

Question 23

Write a note on ER and PR positive breast cancer

Answer 23

The estrogen receptor is a regulator of cellular growth, proliferation and differentiation

Its an intracellular receptor

ER protein is expressed in 70-80% of breast cancer

=> cancer cells grow in response to estrogen

Approx 65 are also PR-positive -> these grow in response progesterone as well

Question 24

What is HER2?

Answer 24

Human epidermal growth factor receptor 2 (RTK)

A gene that makes a protein found on the surface of all breast cells

It is involved in normal cell growth

Question 25

Write a note on HER2 positive breast cancer
(3)

Answer 25

account for 20% of breast cancer

The cells make too much HER2 protein

Cancer is aggressive and fast-growing

Question 26

How can receptors act as biomarkers

Answer 26

The presence or absence of receptors can be used to detect and predict the outcomes of cancer