Cancer 1 Flashcards
what are the types of conventional chemotherapeutic agents?
- alkylating agents
- antimetabolites
- natural products
- miscellaneous agents
- hormones and antagonist
what are the examples of alkylating agents?
nitrogen mustard, erthylenimines & methylmelaines, nitrosoureas (cyclophosphamide, carmustine)
what are the examples of antimetabolites
purine & pyrimidine analogs (5-FU, Gemcitabine, 6-MP)
what the examples of natural products?
vinca alkaloids, taxanes
miscellaneous agents
cisplatin, carboplatin, hydroxyurea, mitoxantrone
what are the two major proteins that control cell cycle progression?
- cyclins (the regulatory proteins)
2. Cyclin-dependent kinases (Cdks)
Cyclin + Cdk function as
heterodimers that phosphorylate target proteins
Cdks have no kinase activity unless associated with a
cyclin
cycline determines
which proteins to be phosphorylated by the cycin-Cdk complex
what result in the release of E2F?
hyperphosphorylation of Rb
what is the role of E2F?
it activates the transcription of genes whose products control progression from G1 to S phase
how do cancer drugs such as cisplatin, doxorubicin work?
- activate p53 –> activate p21
(FA) what is apoptosis?
- programmed cell death
- ATP required
- intrinsic or extrinsic pathway
- both pathways lead to activation of cytosolic caspases
define term pyknosis
nuclear shrinkage and basophilia
karyorrhexis
nuclear fragmentation
karyolysis
nuclear fading
what are the molecular and biochemical changes in apoptosis?
- activation of proteases: caspases and serine proteases
- DNA fragmentation: nucleases
- loss of mitochondrial membrane potential
- cyctochrome C release from mitochondria into cytosol
how are caspases utilized in mediating apoptosis?
they are utilized in a cascade known as “caspase cascade”
what are the two major apoptotic pathways responsible for activation of caspase cascade?
- death receptor-dependent pathway (extrinsic pathways)
2. mitochondrial pathway (intrinsic)
(FA) what are the two extrinsic pathways?
- ligand receptor interactions (Fas ligand binding to Fas (CD95))
- Immune cell (cytotoxic T-cell release of perforin and granzyme B)
(FA) what is the intrinsic pathway?
occurs during embryogenesis, hormone induction
What is Bax?
pro-apoptotic
What is Bcl-2?
anti-apoptotic
what are the two types of anticancer drug resistance?
intrinsic or acquired
some cancer cells with deficiency in Deoxycitidine kinase are
resistance to AraC
