Chemotherapy Drugs II: Specific Drugs Flashcards

1
Q

steroid hormones

A

induce apoptosis thru receptor activation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

antimetabolites

A

interfere with anabolic process of generating nucleotide triphosphates for DNA synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

cross-linking agents

A

blocks strand separation and template processing thru intra- or interstrand interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

topoisomerase inhibitors

A

interfere with enzymatic process of unwinding DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

alkylating agents

A

interfere with replication machinery thru multiple mechanisms of altered binding and base recognition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

anti-tubulin agents

A

interference with spindle fiber formation and separation of chromosomes into daughter cells during mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

targeted agents

A

block cancer associated pathways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

immune modulators

A

block suppressors of immune targeting of tumors or activate immune cells to tumor surveillance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

glucocorticoids MOA

A

bind to DNA, alter gene txn in response to hormone binding. direct lytic effect on malignant cells in lymphoid malignancies, leukemia, myeloma. ability to induce apoptosis dependent upon balance of pro and anti apoptotic proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

side effects of glucocorticoids

A
  • metabolic effects: inc blood GLU, protein degradation
  • circulatory effects: inc cardiac output, inc sensitivity to catecholamines, inc renal Na+ retention
  • musculoskeletal effects
  • immune modulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

nitrogen mustard is what type of drug

A

alkylating agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the common cellular target of alkylating agents?

A

crosslink DNA, cell cycle non-specific, so can bind DNA in any place of cell cycle. inhibits DNA synthesis thru damage to the nucleic acid template

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

MOA of alkylating agents

A

covalently binding to cellular macromolecules to inhibit DNA synthesis by damaging the nucleic acid template

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

side effects of alkylating agents

A

BAG: bone marrow suppression, alopecia, gastrointestinal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

BAG effects

A

bone marrow suppression
alopecia
gastrointestinal
basically all the rapidly dividing cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what type of drug is cyclophosphamide?

A

alkylating agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

cytoxan

A

cyclophosphamide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how is cyclophosphamide administered?

A

IV or oral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is unique about cyclophosphamide?

A

it must be metabolized in liver to be active!! makes active metabolites phosphoramide mustard and acrolein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is a negative sequelae of administering cyclophosphamide?

A

SHC: sterile hemorrhagic cystitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is cyclophosphamide used to treat?

A

lymphoma, sarcomas, mammary gland, mast cell tumor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what effects does cyclophosphamide have on cats?

A

GI effects more common in cats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

cyclophosphamide causes GI effects more common in what species?

A

cats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what drug is not active until it is in the liver?

A

cyclophosphamide- must be metabolized in liver to be active!!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
sterile hemorrhagic cystitis MOA
- cyclophosphamide - acrolein damages bladder tissue when excreted in the urine - 10% of dogs develop SHC when treated with CP
24
T/F: you can give cyclophosphamide orally in addition to IV, but it will have decreased exposure to the "active drug"
false- oral dosing of CP has same exposure to active drug as IV, exposure to parent drug is decreased
25
you are treating a lovely golden retriever named Buddy for lymphoma with cyclophosphamide. you are very astute and remember from your CSU days that Buddy is at increased risk for sterile hemorrhagic cystitis. what are your options if this develops?
- furosemide diuresis: increases clearance of acrolein in bladder - Mesna: decreases incidence by collecting in bladder and "capturing" the acrolein - switch to another alkylator like Chlorambucil
26
the owner of Buddy is concerned about potential GI effects of cyclophosphamide. what do you tell her?
not worried about them in Buddy because he is a dog; GI effects seen more commonly in cats
27
why would administering cyclophosphamide not be useful?
it is a pro-drug and requires metabolic activation by the liver
28
chlorambucil
- alkylating agent, alternative to cyclophosphamide - oral only, delayed onset of action. metabolized to mustard - cerebellar toxicity ? brain fog? - used for chronic lymphocytic leukemia, lymphoma, mast cell tumors
29
melphalan (Alkeran)
- alkylating agent - oral, active parent drug - multiple myeloma - active uptake by amino acid transporters
30
CCNU
Lomustine, CeeNU
31
CCNU (Lomustine, CeeNU)
- oral, completely absorbed - crosses BBB by passive diffusion - myelosuppression, thrombocytopenia, hepatic toxicities associated with chronic use - mainly used for mast cell tumors and lymphoproliferative disorders in cats, but also in dogs with mast cell and histiocytic sarcoma too
32
non-classic alkylating agents
dacarbazine and procarbazine not 1st line drugs, likely won't see both act as methylating agents: inhibits DNA and RNA synthesis
33
antimetabolites
interferes with cellular metabolism associated with making the building blocks of DNA and interfering with DNA and RNA synthesis
34
ultimate effect of antimetabolites
purine/pyrimidine biosynthesis: depletes building blocks/things needed for making DNA
35
what classes are included in the antimetabolites?
- antifolates - 5-fluoropyrimidines - cytidine analogs
36
methotrexate
- antimetabolite, folate analog that blocks purine and thymidylate biosynthesis by inhibiting dihydrofolate reductase
37
methotrexate toxicity
GI toxicity bc of enterohepatic recycling and it accumulates in GI tissue not really used anymore
38
cytosine arabinoside/ara-C, cytarabine
- antimetabolites - analog to deoxycytidine, phosphorylated to ara-CTP because cells thing it's cytadine - ara CTP is an inhibitor of DNA polymerase a: gums up works
39
what is cytosine arabinoside/ara-C/cytarabine good for?
- crosses into CNS: used for tumors that have potential CNS involvement!! - can be delivered as SC inj - makes things not H bond right; DNA helix won't work right
40
gemcitabine
- antimetabolite, phosphorylated into many things - dFdCTP inhibits DNA polymerase: depletes deoxyribonucleotide pools thru inhibition of ribonucleotide reductase - incorporated into DNA strands is a toxic lesion X0 - veterinary use is sparse, dosed IV
41
5-Fluorouracil MOA
- antimetabolite - gets in via facilitated transport, metabolized to phosphorylated forms - incorporated into both DNA and RNA: messes up synthesis and function - FdUMP depletes thymidine pools - metabolized to an inactive form by dihydropyrimidine dehydrogenase (DPD)
42
what is 5-Fluorouracil used for?
treatment of epithelial tumors
43
5-Fluorouracil is contraindicated in what species and why?
cats, deficiency in DPD leading to serious toxicity (DPD is what metabolizes drug to inactive form)
44
antitumor antibiotics
multiple MOA: form complexes w DNA, inhibit DNA/RNA synthesis, cell cycle nonspecific BAG most common used in vetmed!!
45
single most active agent used in vet oncology
doxorubicin
46
MOA of doxorubicin
- inhibition of DNA/RNA polymerases - topoisomerase II inhibition - alkylation of DNA - reactive oxygen generation - perturbation of cellular Ca2+ homeostasis - inhibition of thioredoxin reductase - interaction with plasma membrane components
47
metabolism of doxorubicin
- widely distributed to tissues - metabolized hepatically and extra-hepatically
48
toxicities of doxorubicin
GI, hematopoietic, cardiac***!!! associated w lifetime dose
49
why should you be super careful w PPE when administering doxorubicin?
it is a severe vessicant, causing extravasation damage: if it comes out of blood and into tissue, that tissue will become necrotic and will kill tissue!!!
50
what drug is known for its unique cardiac toxicities?
doxorubicin
51
how does doxorubicin cardiac toxicity relate to dose?
cumulative cardiac toxicity is related to total lifetime dose (250mg/m^2)
52
what is the best way to administer doxorubicin?
10-30 minute infusion times to decrease acute cardiotoxic events: acute cardiotoxicity has been observed with rapid infusion
53
red death
doxorubicin
54
doxorubicin summary
- unique toxicities: cardiac in dog, renal in cat - most widely used drug in vet oncology
55
what is doxorubicin toxicity in cats
renal
56
dosing doxorubicin in small animals
A standard dose is 30 mg/m2 but for smaller dogs (<15 kg) and all cats a dose of 1 mg/kg is commonly used.
57
doxorubicin in humans and dogs
similar variability observed, time-course of drug exposure is similar. not the DOSE, it's the exposure and metabolism
58
what is doxorubicin used for?
lymphoma, osteosarcoma, mammary gland tumors, thyroid, sarcomas
59
other "rubicins" vs doxorubicin
epirubicin, daunarubicin, idarubicin (oral) less cardiac toxicity, greater expense and generally not much of an advantage over doxorubicin
60
mitoxantrone
- antitumor abx - synthetic doxorubicin analog with similar MOA - not near as active in terms of generation of RO
61
MOA of mitoxantrone
similar to doxorubicin, DNA intercalation and inhibition of DNA and RNA polymerases, topoisomerase II inhibition
62
when do you use mitoxantrone?
- used as cardiac-sparing drug in dogs that have reached cumulative max level of doxorubicin dosing, or that show cardiac abnormalities - primarily used in lymphoproliferative disorders and recently in TCC of bladder
63
actinomycin D
- antitumor abx - interacts w double-stranded DNA to block txn, binds to single-stranded to inhibit txn - inhibition of txn leads to inhibition of RNA and protein synthesis
64
when do you use actinomycin D?
- rapidly distributes, slowly eliminated - multi agent protocol use for lymphoproliferative disorders in relapse setting and as sub for doxo in dogs with cardiac abnormalities
65
how are mitoxantrone and actinomycin D administered?
IV both have BAG
66
microtubule targeting
interfere with tubulin formation/function. cell cycle specific phase! M phase: doesn't allow to separate or assemble
67
what are the 2 classes of microtubule targeting drugs
1. vinca alkaloids - pink periwinkle 2. taxanes - japanese yew tree
68
what is the difference between vinca alkaloids and taxanes?
vinca alkaloids prevent microtuble ASSEMBLY taxanes prevent microtubule DISASSEMBLY
69
vinca alkaloids drugs
vincristine and vinblastine
70
vinca alkaloids uses
- inhibit MT assembly, delivered by IV - vincristine is part of the CHOP protocol used in lymphoma - vinblastine is used for k9 mast cell tumors
71
vincristine
antimicrotubule agent, vinca alkaloid used for lymphoma in CHOP protocol
72
vinblastine
antimicrotubule agent, vinca alkaloids used for canine mast cell tumor txt
73
taxane drugs
paclitaxel & docetaxel - inhibit MT de-polymerization, delivered IV - highly insoluble, so has to be given with another thing that causes hypersensitivity reactions. this has limited its use, but new formulations may change that !
74
side effects of vincristine
- peripheral neuropathy - minimal myelosuppression = AG of side effects
75
side effects of vinblastine
- IV! vessicant - BAG, less neurotoxicity
76
which vinca alkaloid cures transmissible venereal tumor?
vincristine
77
78
79