Cancer drugs

Question 1

Recall the cell cycle

Answer 1

G1 phase - cell contents duplicate
*G1 checkpoint

S phase- DNA synthesis (replication). separated by helicase. topoisomerase II fixes the coils. nucleotides- pyrimidine cytosine and thymine. purines adenine, guanine. DNA polymerase makes a new strand.

G2 phase- DNA double-check for errors (cell prepares itself for M phase)
*G2 checkpoint

Mitosis (M phase) - cell splits into two identical daughter cells
*M checkpoint

Question 2

M phase inhibitors

Answer 2

• Eribulin
• Paclitaxel
• Vincristine
• Vinblastine

MOA: inhibit the microtubules so they can’t separate metaphase to anaphase. cells can’t divide.

Question 3

M phase inhibitor side effects

Answer 3

• eribulin- arthralgia
• paclitaxel- neuropathy
• vincristine/vinblastine- neurotoxicity.

Question 4

GI inhibitors

Answer 4

• cisplatin
• busulfan
• cyclophosphamide
• carmustine

MOA: they all cross-link DNA

Question 5

GI inhibitors side effects

Answer 5

• cisplatin: ototoxicity, nephrotoxicity
  treat with amifostine/saline
  “makes the kidney go (cis)SPLAT(in)”
• busulfan: pulmonary fibrosis
  fib*busulfan
• cylcophosphamide- haemorrhagic cystitis SIADH
  treat with mesna
  (HOSP if haemorrhagic cystitis)
• carmustine CNS toxicity.

Question 6

S phase inhibitors

Answer 6

azathioprine
6-mercaptopurine
*metabolised by xanthine oxidase

cladribine
cytarabine
5-fluorouracil
hydroxyurea
methotrexate

inhibit purine synthesis

Question 7

S phase side effects

Answer 7

methotrexate- myelosuppression

cladribine- nephron/neurotoxicity
cytarabine- pancytopenia

Question 8

G2 phase inhibitors

Answer 8

etoposide
teniposide
MOA: inhibit topoisomerase II
(side= two sides= II)

irinotecan
topotecan
inhibit topoisomerase I
(can= I= one)

Question 9

antitumor antibiotics

Answer 9

doxorubicin
danorubicin
MOA: intercalating DNA
Side effect: dilated cardiomyopathy

bleomycin
MOA: generate free radicals
side effects: pulmonary fibrosis

Question 10

mitosis

Answer 10

1. prophase
2. metaphase- attach to the centromeres
3. anaphase- chromosomes are separated and reach either end of the cells
4. telophase- cell membrane constricts ready to separate

Question 11

alkylating agents

Answer 11

bin covalently via alkyline groups to DNA. cell arrest

• cyclophosphamide
• cisplatin

Question 12

anti metabolites

Answer 12

interfere with normal cellular metabolism of nucleic acid.

MOA disrupts DNA/RNA metabolism production. interrupts the S phase of cell cycle.

Question 13

antitumour antibiotics

Answer 13

inhibits helicase
inhibits topoisomerase II
produces reactive oxygen species

doxorubicin
daunorubicin

Question 14

anti-microtubule agents

Answer 14

disrupts M phase of the cell cycle leading to cell arrest

M phase consists of prophase, metaphase, anaphase and telophase.