Antimitotics Flashcards
(13 cards)
What is the main mechanism of action of antimitotic cancer drugs?
They disrupt microtubule dynamics arresting cells in mitosis and leading to cell death
Name the two main classes of antimitotic drugs and given an example of each
Microtubule stabilising agents e.g. Paclitaxel
Microtubule de stabilising agents e.g. vincristine
How do taxanes work?
They stabilise microtubules by binding to beta tubulin preventing depolymerisation and causing mitotic arrest
For which cancers are taxanes usually used
Breast lung and ovarian cancers
What are common side effects of taxanes
Peripheral neuropathy, myelosuppression and skin reactions
How do Vinka alkaloids work?
They bind beta tubulin inhibit micro tubulin polymerisation and disrupt spindle formation leading to mitotic arrest
What are vinca alkaloids used to treat?
Lymphoma, leukaemia, breast cancer and lung cancer
Name a newer microtubule stabilising agent and its clinical use
Eribulin used for metastatic breast cancer that is resistant to taxanes and anthracycline
What is a key mechanism of resistance to antimitotic drugs in cancer cells?
Overexpression of efflux pumps like p glyco protein MDR1 which export drugs out of the cell
What is a notable side effect of Vinka alkaloids
Neurotoxicity especially peripheral neuropathy
What are epothilones and what are they used for?
Micro tubule stabilising agents used for metastatic or locally advanced breast cancer resistant taxes and anthracyclines
How does mitotic arrest by antimitotic drugs lead to cancer cell death?
Prolonged mitotic arrest triggers apoptosis via pathways involving BCL2 family proteins and sometimes death receptor signal
What is the influence of cremophor?
Concentration rises during infusion,
critical micellar concentration
sequesters Paxitaxel (hides away)
plasma paxitaxel concentration elevated
