chemotherapeutics

Question 1

goals of chemotherapy

Answer 1

1) kill tumor without killing healthy tissue
2) appropriate drug for tumor
3) dosages calculated to obtain sufficient concentration at tumor site
4) complementary drug combos

Question 2

log kill/fractional kill

Answer 2

1) most anti-cancer drugs kill a constant fraction of cells
2) eg. drugs kills 50% of each dose
3) aims to maintain without increasing tumor burden, or preferably to reduce it

Question 3

antineoplastic drugs inhibit cell cycle specificity

Answer 3

1) act on DNA
2) inhibit parts of cell cycle

Question 4

drug target summary

Answer 4

1) antimetabolites
2) topoisomerase inhibitors
3) alkylating agents

Question 5

FDA approved head and neck cancer drugs (KNOW)

Answer 5

1) methotrexate
2) cisplatin
3) bleomycin
4) docetaxel
5) fluorouracil
6) hydroxyurea
7) cetuximab
8) pembrolizumab
9) nivolumab

Question 6

DNA cross linkers

Answer 6

1) form covalent bones with DNA or RNA
2) increase head and neck survivial by 15%

Question 7

examples of DNA cross linkers

Answer 7

1) cisplatin, oxaliplatin, carboplatin
- centered around platinum
2) nitrosoureas
- lomustine and carmustine
- cross BBB
3) nitrogen mustards
- cyclophosphamide, methchlorethamine

Question 8

cell overcomes DNA cross linkers

Answer 8

1) can increase tolerance
- loss of DNA mismatch repair
- bypass DNA adducts
- decreases apoptosis
2) increase removal from DNA
- increased nucleotide excision repair

Question 9

nitrosoureas dental considerations

Answer 9

1) stomatitis
2) nausea and vomiting
3) mucositis
4) dysphagia
5) Gi toxicity, hepatotoxicity
6) immunosuppression
7) myelosuppression
8) thrombocytopenia
9) secondary neoplasm

Question 10

platinum compounds dental considerations

Answer 10

1) same as nitrosoureas
2) loss of hearing

Question 11

antimetabolites (DNA synthesis inhibitors) examples

Answer 11

1) methotrexate
- inhibits dihydrofolate reductase
- inhibit thymine production
2) purine or pyrimidine analogues
- fluorouracil
- capecitabine

Question 12

methotrexate ADR

Answer 12

1) very toxic!
2) significantly enhanced by NSAIDs and fatal interaction

Question 13

antibiotics examples

Answer 13

1) non-anthracyclines
2) bleomycin
- DNA double strand scission
3) actinomycin-D
- intercalating agent

Question 14

bleomycin potential mechanism

Answer 14

1) metal chelation
2) free radical formation
3) DNA disruption

Question 15

antibiotics side effects

Answer 15

1) bleomycin
- pulmonary pneumonitis, fibrosis
- low myelosuppression, minimal nausea, lack of local tissue toxicity
2) actinomycin D
- dose limiting mucositis, stomatitis
- nematotoxicity
- tissue necrosis at injection site

Question 16

plant alkaloids examples

Answer 16

1) vinca alkaloids
- vincristine, vinblastine
- prevents polymerization
2) taxoids
- paclitaxel
- docetaxel
- stabilizes skeleton, doesn’t break down

cell skeleton poisons, prevent cell division

Question 17

hydroxyurea/hydroxycarbamide

Answer 17

1) selectively inhibit ribonucleoside diphosphate reductase
2) halts cell cycle in G1/S
3) radiotherapy sensitizer

Question 18

immunotherapy examples

Answer 18

1) cetuximab
- anti epidermal growth factor receptor
- direct inhibition of cancel cell growth signals
2) tremelimumab and pembrolizumab
- act on the T cells