Anticancer Drugs Flashcards
Alkylating drugs (mitomycin & cisplatin) MOA
carbonium ion –> covalent bonds w/ DNA –>impedes replication
Antimetabolites MOA
block or subvert one or more metabolic pathways in DNA synthesis
Cytotoxic antibiotics MOA
blocks mammalian cell division
Vinca Alkaloids MOA
binds to tubulin –> prevents formation of mitotic spindles–> arrests cell at metaphase
Protein kinase inhibitor MOA
blocks tyrosine kinases that tranduce growth signals
Methotrexate MOA (2)
inhibits dihydrofolate reduction,
block DTMP & purine synthesis
Doxorubicin MOA
blocks topoisomerase II fxn
5-fluorouracil MOA
inhibits DTMP synthesis (DNA only)
L-asparaginase MOA
catalyses hydrolysis of l-asparagine to l-aspartic acid & ammonia –> deaminates asparagine & inhibits protein synthesis
Paclitaxel & Docetaxel (Taxanes) MOA
Stabilizes microtubules in the polymerized state
What is commonly seen w/ BM toxicity due to chemotherapuetics?
leukopenia
BCG MOA
stimulates immune system to recognize tumor cells
What molecule dissociates once Cisplatin enters the cell?
Cl
Methotrexate is a _____ ANTagonist.
folate
Solubility of methotrexate
low lipid solubility
actively taken up by cells via folate transport system
4 reasons for using combos of cancer drugs on a TX schedule (TQ)
- Incr. cytotoxicity w/o increasing gen. toxicity
- Decr. resistance to individual agents
- Permit BM regeneration
- More effective when given as 1 or 2 LG doses
Main problem of alkylating agents
Strong cross-resistance
What enzyme activates Cyclophosphamide in the liver? (it’s a pro-drug) (TQ)
CYP450
Slowest working alkylating agent? Benefits?
Chlorambucil
lowest toxicity
Do NOT use cytotoxic antibiotics w/ what other form of therapy?
radiotherapy (toxicity)
Doxorubicin & dactinomycin inhibit DNA synthesis by interferring w/ _____.
Topoisomerase II
What type of cells does bleomycin work on?
non-dividing cells
Depletion of EXTRAcellular stores of _____ lead to inhibition of protein synthesis.
L-asparaginase
L-asparaginase only attacks cells lacking what enzyme?
L-asparagine synthetase
List 2 taxanes derived from Taxus spp plants (bark of yew tree).
Paclitaxel
Docetaxel
Which drugs should you NEVER give to horses (death!)?
Paclitaxel
Docetaxel
List the 3 tyrosine kinase inhibitors
Imatinib
Toceranib
Mastinib
Tyrosine kinase inhibitors block _______.
angiogenesis (slows down tumor growth)
Bevacizumab blocks the ______ receptor.
vascular endothelial growth factor receptor
Cetuximab blocks the _____ receptor.
epidermal growth factor receptor
Trastuzumab blocks the _____ receptor.
human epithelial R2
Imatinib blocks the ______ receptor.
platelet derived growth factor receptor
List the 3 antibodies that target epidermal growth factor receptors.
Cetuximab
Trastuzumab
Bevacizumab
Which antibody works on ErbB-1 expressing tumors?
Cetuximab
Which anitbody works on ErbB-2 expressing tumors?
Trastuzumab
Which antibody works on VEGFR in mastocytoma cells?
Bevacizumab
Possible problem when using glucocorticoids & chemotherapeutics together.
Mutli-drug resistance
via induction of PgP (permeability glycoprotein)
Which 3 drugs have demonstrated resistance due to decreased accumulation of cytotoxic drugs? (TQ)
Doxorubicin
Vinblastine
Dactinomycin
Mode of resistance for methotrexate? (TQ)
Decreased drug uptake by the cell
Mode of resistance for 5-fluorouracil? (TQ)
Insufficient activation of the drug
Mode of resistance for antimetabolites. (TQ)
Increased utilization of alternative metabolic pathways
Mode of resistance for alkylating agents. (TQ)
Rapid repair of drug induced lesions
Mode of resistance for Doxorubicin? (TQ)
Altered activity of the drug’s target (topoisomerase II)
Active metabolite of Cyclophosphamide
Acrolein
List 5 nitrogen mustards (alkylating agents).
Cyclophosphamide
Melphalan
Chlorambucil
Ifosfamide
Alkyl sulfonate alkylating agent
Busulfan
Non-classical alkylating agent
Dacarbazine
Nitrosurea alkylating agent
Lomustine
List 2 platinum coordination complex alkylating agents
Cisplatin
Carboplatin
List 4 cytotoxic antibiotics
Doxorubicin
Dactinomycin
Bleomycin
Mitomycin