Vincristine and Vinblastine MOA
Antimicrotubule agents
Inhibit microtubule assembly (disruption of the mitotic spindle)
VinCRISTINE use
Lymphoma
Transmissible venereal tumors
VinBLASTINE uses
Canine mast cell tumors
Which chemotherapeutic agents are topoisomerase inhibitors?
Epipodophyllotoxins (Etoposide and Teniposide)
But also mitoxantrone (inhibits topoisomerase II)
Steroids MOA
Induces killing of hematopoietic cancer
cells through interaction with the glucocorticoid receptor and the
induction of apoptosis
Platinum (Carboplatin and Cisplatin) MOA
Covalent binding to DNA through displacement reactions resulting in bifunctional lesions and interstrand
or intrastrand cross-links.
Toxicity with cisplatin
Nephrotoxicity
Cisplatin/carboplatin use
Cisplatin - Canine osteosarcoma (OSA)
Carboplatin - Better tolerated - OSA, other sarcomas and carcinomas
Why is carboplatin preferred to cisplatin?
Carboplatin is preferred to cisplatin because of the reduced incidence of
nausea/vomiting, the absence of nephrotoxicity, and ease of administration.
Hydroxyurea MOA
Inhibitor of ribonucleotide reductase - inhibition of DNA synthesis
Hydroxyurea clinical use
bone marrow disorders such as polycythemia vera and granulocytic
leukemias
L-asparginase MOA
Hydrolysis of L-asparagine to L-aspartic acid»_space; depletion of L-asparagine»_space; inhibition of protein synthesis»_space; apoptosis
L-asparginase use
Lymphoproliferative disorders
Relapsed lymphoma
Mechlorethamine MOA
Alkylating agent (Nitrogen mustard) - DNA cross-linking
Mechlorethamine Use
Lymphoma in dogs
Melphalan MOA
Alkylating agent (nitrogen mustard) - direct alkylating activity
How is melphalan transported into the cell?
How is transport into the cell blocked?
2. Blocked by the amino acid leucine.
Melphalan use
Myeloma
Cyclophosphamide MOA
Alkylating agent (nitrogen mustard) Bifunctional alkylation and cross-link production.
What is the active metabolyte of cyclophosphamide?
Phosphoramide mustard
What is a major side effect of cyclophosphamide?
Hemorrhagic cystitis
Cyclophosphamide USE
Multiagent protocols for lymphoma in both dogs and cats.
Chlorambucil MOA
Alkylating agent (nitrogen mustard derivative) Direct bifunctional alkylating ability
Chlorambucil clinical use
Dogs - control of chronic lymphocytic leukemia (CLL)
Cats - Low-grade GI lymphoma in cats.