Carla - Receptors and Disease Flashcards
Give some ways cell communication can go wrong
(3)
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
Give an example of a disease caused be a lose of a signal
Type 1 diabetes
Give an example of a disease caused a signal not being able to reach it’s target
Multiple sclerosis
Give an example of a disease caused by a target ignoring a signal
Type 2 diabetes
Give an example of a disease caused by multiple breakdowns in signalling
Cancers
Strokes
Alzheimers
Chronic and complex diseases
What are the two types of receptor linked diseases?
Congenital
Acquried
What are the two types of receptor linked diseases?
Congenital
Acquired
What causes familial hypercholesteremia
A defect in an LDL receptor
What is familial hypercholesteremia (FH)
Significantly elevated low-density lipoprotein cholesterol
Early onset
20x higher risk of coronary artery disease
Give an example of a congenital receptor disease
Myasthenia gravis
What is myasthenia gravis?
A disease of the postsynaptic neuromuscular junction (NMJ) where nicotinic acetylcholine (ACh) receptors (ACHRs) are targeted by antibodies
What are the symptoms of myasthenia gravis?
Weakness and rapid fatigue of any of the muscles under voluntary control
In general what happens to the receptor in myasthenia gravis?
Loss of receptor function - the message is not heard
What do practitioners have to consider when working with myasthenia gravis patients?
They are extremely sensitive to anaesthetic
What happens in acquired receptor disease?
Good receptors turn bad
Give an example of a receptor that can be affected by acquired receptor diseases?
Receptor tyrosine kinases
What different alterations can be made to receptor tyrosine kinases?
(3)
Amplification
Overexpression
Somatic mutation resulting in increased receptor signalling
List some diseases caused by RTK mutations
Dwarfism
Craniosynostosis
Heritable cancer susceptibility
Venous malformation
Piebaldism
What happens when there is a gain of function mutation of a receptor tyrosine kinase?
Result in constitutive receptor activation
What happens when there is a loss of function mutation of a receptor tyrosine kinase?
Result in non-functional or dominant negative receptors
Write a note on receptors in oncogenesis
Cancer often caused by receptors involved in growth, proliferation and differentiation
e.g. breast cancer can have receptors which are hormone-positive
What are the three types of hormone positive breast cancer?
ER positive
PR positive
HER2 positive
Write a note on ER and PR positive breast cancer
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
What is HER2?
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
Write a note on HER2 positive breast cancer
(3)
account for 20% of breast cancer
The cells make too much HER2 protein
Cancer is aggressive and fast-growing
How can receptors act as biomarkers
The presence or absence of receptors can be used to detect and predict the outcomes of cancer
