6/14 UWorld Flashcards
MOA of Cladribine
- Sketchy:
- caveman clad in bear skin
- Cytotoxic purine analog (–> purine stone hammer)
- Is resistant to adenosine deaminase, enzyme that normally degrades purine analogs
- Can incorporate into DNA causing
- DNA breaks
- Inhibition of DNA synthesis and repair by inhibiting DNA polymerase alpha and beta
MOA of Cytarabine
Sketchy = saber tooth tiger
Pyrimidine analog
Inhbitis DNA pol alpha and beta
MOA of Gemcitibine
Sketchy = geods with gems inside
Cytotoxic pyrimidine analog - inhibits DNA polymerase, blocking DNA synthesis and repair
What are the alkylating agent anti-neoplastics?
Cyclophosphamide - cyclops
Busulfan - beautiful sirens
Nitrosoureas - centaurs (“-mustine” - mustang)
MOA, uses, and adverse effects of Cyclophosphamide
- Mechanism of action:
- Works by attaching an alkyl group to the guanine base of DNA at the #7 nitrogen atom
- This leads to intra- and inter-strand cross-links
- Cell division halts and the cell undergoes apoptosis
- This is cell cycle NON-specific
- Uses:
- Hematologic and solid malignancies (e.g. leukemias and lymphomas, breast cancer, ovarian cancer
Immunosuppressive (e.g. nephrotic syndrome, nephritic syndrome, vasculitis, autoimmune hemolytic anemia)
- Adverse effects
- Myelosuppression (leading to cytopenias)
- Hemorrhagic cystitis
- Cyclophosphamide is metabolized by the kidney into a molecule that is toxic to uroepithelial cells if in contact with the cells for too long
- Increased risk for bladder cancer (high grade transitional cell carcinoma)
- Hyponatremia due to SIADH
- Toxic to ovaries and testes
- Can cause infertility and premature menopause
- Can cause decrease in sperm count and irreversible azoospermia
How do you prevent hemorrhagic cystitis from use of Cyclophosphamide
- Prevent with aggressive hydration and co-administration with 2-mercaptoethanesulfonate (MESNA), which will bind and inactivate the toxic metabolite
- Sketchy = protective maze around cystitis fountain
- Cyclophosphamide is metabolized by the kidney into a molecule that is toxic to uroepithelial cells if in contact with the cells for too long
MOA, uses, and adverse effects of Busulfan
- Mechanism of action
- Alkylating agent that forms DNA intra-strand cross-links, preventing DNA replication and leading to apoptosis
- Uses:
- Used as a conditioning agent prior to bone marrow transplant – aka significantly depletes the bone marrow
- Adverse effects:
- Lung toxicity (e.g. acute lung injury, interstitial fibrosis, alveolar hemorrhage)
- Skin darkening (“busulfan tan”)
Names of Nitrosoureas
- Drugs:
- “-mustine**” suffix (e.g. **Carmustine, Lomustine)
- à centaur is a mustang horse
-
Streptozotocin
- à striped zebra centaur
- “-mustine**” suffix (e.g. **Carmustine, Lomustine)
MOA, uses, and adverse effects of nitrosoureas
- Uses:
- Brain tumors (e.g. glioblastoma multiforme)
- Are highly lipophilic so can cross the BBB
- Adverse effects:
- Neurotoxicity (e.g. convulsions, dizziness, atazia)
Describe the correlation betweeen azathioprine and Allopurinol
Azathioprine and 6-MP are metabolized by xanthine oxidase
So they will have increased toxicity if given with Allopurinol (which inhibits xanthine oxidase, thus preventing the breakdown of AZA/6-MP)
MOA, uses, and adverse effects of platinum analogs (Cisplatin, Carboplatin
- MOA:
- Cross-links DNA
- Uses:
- Solid malignancies: Testicular, bladder, ovary, and lung carcnioma
- Adverse effects:
- Neurotoxoity
- Ototoxicity
- Peripheral neuropathy
- Nephrotoxicity
- Immunosuppression
- Myelosuppresion
- Neurotoxoity
What drug can be used to protect against Cisplatin-induced nephrotoxicity, and what is it’s MOA?
- Amifostine
- Sketchy = amethyst
- Mechanism of action
- Is an organic thiophosphate
- Can bind to and detoxify the reactive metabolites (free radicals) of Cisplatin
MOA, uses, and adverse effects of Bleomycin
- Mechanism of action
- Antitumor antibiotic
- Small peptide with a DNA binding region on one end and an iron binding region on the other end
- After binding to DNA, it chelates metal ions, producing a pseudo-enzyme that reacts with O2 to produce superoxide and hydroxide free radicals that cleave DNA
- Free radicals leads to single and double-stranded breaks of DNA
- Is cell cycle specific – cells become arrested in G2
- = Galleon (GII)
- Uses:
- Hematologic and solid malignancies (e.g. Hodgkin and Non-Hodgkin lymphoma, germ cell tumors, squamous cell carcinoma of the skin, cervix, and vulva
- Adverse effects:
- Pulmonary toxicity
- Skin toxicity (e.g. rash, exfoliation, hyperpigmentation, atrophic striae)
- Stomatitis and mucositis
- Alopecia
What drugs are part of the Anthracyline family and what is their MOA
- Sketchy = Santa Anthracycline
- Drugs:
- “-rubicin**” suffix (e.g. **Doxorubicin, Daunorubicin)
- Mechanism of action:
- Antitumor antibiotic
- Promote the generation of oxygen free-radical through an iron-dependent reductive process
- Also bind to DNA through intercalation – are planar molecules that can fit themselves between base pairs of DNA – leading to blocking of DNA and RNA synthesis
- Uses:
- Broad range of solid and hematologic malignancies
Adverse effects of anthracyclines
Drug used to prevent adverse effect
- Cardiotoxicity secondary to buildup of free radicals in cardiac myocytes
- Presents as dilated cardiomyopathy with symptoms presenting months after drug is stopped
-
Dexrazoxane is an iron chelator that prevents anthracycline-induced cardiotoxicity
- = chelating/clinging the heart sack
- = is on the deck (dex-) with a razor (-razoxane)
- Myelosuppression
- Stomatitis and mucositis
- Alopecia
MOA, uses, and adverse effects of Actinomycin D
- Sketchy = artifact-inomycin (doll artifact)
- Mechanism of action:
- Is an antitumor antibiotic
- Intercalates into DNA, blocking DNA and RNA synthesis
- Uses:
- Numerous pediatric malignancies (e.g. Wilms tumor, Ewing sarcoma, rhabdomyosarcoma)
- Adverse effects:
- Alopecia
- Myelosuppression
MOA of Etoposide and Teniposide + what part of the cell cycle they work on?
- Mechanism of action
- Topoisomerase II inhibitors (double stranded breaks to relieve supercoiling)
- Prevent the re-ligation of double strand breaks induced by topoisomerase II
- Cycle specific
- Inhibit DNA synthesis, arresting cells in the S phase
- Also block the G2 phase (double check and repair) of the cell cycle in cells that happen to make it past the S phase
MOA, uses, and adverse effects of Topotecan and Irniotecan
- Mechanism of action
- Topoisomerase I inhibitors (single stranded nicks to relieve supercoiling)
- Uses:
-
Topotecan
- Ovarian cancer and small cell lung cancer
-
Irinotecan
- Colon cancer
-
Topotecan
- Adverse effects:
- Myelosuppression
- Severe diarrhea
- = loose bird stool
MOA, cell cycle, and adverse effects of Vincristine and Vinblastine
- Mechanism of action
- Cytotoxic vinca alkaloid
- Inhibit microtubule production and mitotic spindle assembly
- This arrests the cell in metaphase and cell division is brought to a halt
- Cell cycle specific
- Block mitosis – M phase
- Uses:
- Hematologic and solid malignancies (e.g. leukemias, lymphomas, pediatric tumors, breast cancer, and germ cell cancer
- Adverse effects:
- Neurotoxicity (e.g. peripheral sensory neuropathy)
- Autonomic dysfunction (e.g. paralytic ileus, constipation)
- = plunger
- Alopecia
- = bald monkey
- Myelosuppression (especially Vinblastine)