401- 403 - Cancer drugs 1 Flashcards
(23 cards)
Etoposide
Bleomycin
Vinca alkaloids and taxols
Antimetabolites
Inhibitors of Nucleotide Synthesis:
- MTX, 5-FU: decrease thymidine synthesis
- 6-MP: decrease purine synthesis
Things that mess with DNA:
- Alkylating agents, cisplatin: cross-link DNA
- Dactinomycin, doxorubicin: DNA intercalators
- Etoposide: Inhibits topoisomerase II
Things that inhibit cell division:
- Vinca alkaloids: inhibit microtubule formation
- Paclitaxel: inhibits microtubule dissasembly
What does methotrexate do?
Folic acid analog that inhibits DHF reductase–> decreased dTMP –> decreased DNA and decreased protein synthesis

What cancers can be treated with methotrexate?
- leukemias
- lymphomas
- choriocarcinoma
- sarcomas
What are the 5 non-neoplastic uses for methotrexate?
- abortion
- ectopic pregnancy
- rheumatoid arthritis
- psoriasis
- IBD
What are the toxicities of MTX?
- Myelosuppression (reverisble with leucovorin)
- Macrovesicular fatty change in liver
- Mucositis
- Teratogenic
What is the mechanism of action of 5-fluorouracil?
Pyrimidine analog bioactivated to 5F-dUMP which covalently complexes folic acid –> inhibits thymidylate synthase –> –> decreased protein synthesis

What are the clinical uses for 5-fluorouracil?
- Colon cancer
- Pancreatic cancer
- Basal cell carcinoma (topical)
What are the toxicities of 5-FU?
- Myelosuppression (not reversible w/ leucovorin; rescue with uridine)
- Photosensitivity
How do you treat an overdose of 5-FU?
Uridine
What is the mechanism of action of cytarabine?
Pyrimidine analog –> inhibition of DNA polymerase
What is the clinical use of cytarabine?
Leukemias and lymphomas
What are the toxicities of cytarabine?
Leukopenia, thrombocytopenia, megaloblastic anemia
CYTarabine causes panCYTopenia
What are 3 purine analog drugs?
- Azathiopurine
- 6-mercaptopurine (6-MP)
- 6-thioguanine (6-TG)
What enzyme activates purine analog drugs?
HGPRT
What are the clinical uses of purine analogs?
- Preventing organ rejection
- RA
- SLE (azathioprine)
- Leukemia
- IBD (6-MP, 6-TG)
What are the three main organs affected by purine analog toxicity?
- Bone marrow
- GI
- Liver
Why does allopurinol increase the toxicity of 6-MP and Azathioprine?
These drugs are metabolized by xanthine oxidase, so allopurinol inhibits their metabolism