Pharmacology of Chemotherapy

Question 1

What is the mechanism of action of cyclophosphamide?

Answer 1

Causes cross linking in DNA

Question 2

Which chemotherapy drug causes haemmorrhagic cystitis and why is this?

Answer 2

Cylophosphamide - When this is broken down in the liver it releases a toxic metabolite called acrolein. This is concentrated in the bladder and causes an inflammatory response which can lead to haemorrhagic cystitis

Question 3

How is the risk of haemmorrhagic cystitis reduced when on cyclophosphamide treatment?

Answer 3

Can be decreased by giving MESNA - this conjugates acrolein and decreases the inflammatory response

Question 4

How does cysplatin work?

Answer 4

Causes cross linking in DNA

Question 5

How does bleomycin work?

Answer 5

Degrades preformed DNA

Question 6

What is the main adverse effect of bleomycin?

Answer 6

Lung fibrosis

Question 7

What is the mechanism of action of anthracycline (eg doxorubicin)?

Answer 7

Stabilises DNA topoisomerase II complex and inhibits DNA and RNA synthesis

Question 8

What is the main adverse effect of anthracyclines?

Answer 8

Cardiomyopathy