Pharmacology Flashcards
What is the main target of cancer that we try direct drugs agaisnt?
The frequent cell cycle
Since cancer cell therapy is still working on human cells (and cells that divide rapidly), what is the general therapeutic window for anti-cancer drugs?
Its narrow
What tissues have rapid cell division, which can have problems in anti-cancer drugs?
GI tract
Bone marrow
Hair
Which polymerase elongates RNA polymers? DNA?
RNA pol elongates RNA polymers
DNA pol elongates DNA
What is the type of repair available for DNA replication errors?
Mismatch repair (MMR)
What is the type of repair available for small base modifications and single-strand breaks?
Base excision repair (BER)
What is the type of repair available for the removal of bulky adducts?
Nucleotide excision repair (NER)
What is the type of repair available for double-stranded breaks?
Homologous recombination or nonhomologous end-joining
Which cancer involves mutations in MLH1, PMS2, MSH2, or MSH6 in 70-80% of the cases?
Hereditary nonpolyposis colon cancer
Sporatic colorectal cancer involves instability of what?
Microsatellites
leading to errors in insertion/deletion of microsatellite repeat sequences
In the inosine monophosphate pathway, which drug inhibits Ribonucleotide reductase, which prevents GMP –> dGMP?
Hydroxyurea
also inhibits AMP –> dAMP
In the inosine monophosphate pathway, which drugs inhibits IMPDH, which prevents IMP –> XMP?
6-mercaptopurine
Thioguanine
In the inosine monophosphate pathway, which drug inhibits IMP –> Adenylosuccinate?
6-mercaptopurine
In the inosine monophosphate pathway, which drugs inhibits dATP –> DNA?
Fludarabine
Cladribine
So hydroxyurea inhibits ribonucleotide reductase inhibits the conversion of what 2 things?
UMP –> dUMP
CTP –> dCTP
Which drug inhibits the conversion of dCTP –> DNA in the aspartate pathway?
Cytarabine
Which drug inhibits the conversion of dUMP –> dTMP in the aspartate pathway by blocking thymidylate synthase?
5-FU
Which drug inhibits DHFR in the aspartate pathway, which inhibits the conversion of DHF –> THF?
Methotrexate
What is the enzyme that uses an RNA template to synthesize TTAGGG repeates to restore the length on the end of the chromosome?
Telomarase
Which does 5-FU form a covalent bond with to inhibit thymidylate synthase?
MTHF
What is the orally bioavailable prodrug of 5-FU?
Capecitabine
What is Capecitabine a first line treatment for?
Colorectal cancer
What is Capecitabine a second line treatment for?
Breast cancer
What is the folate analogue that acts like 5-FU, which is believed to induce thymineless cell death?
Pemetrexed
Which agents are used to treat epithelial tumors, mesenchymal tumors, carcinomas, and sarcomas?
Alkylating agents
Generally, alkylating agents are electrophilic and act on which nucleophilic sites on DNA?
N-7 and O-6 of guanine
What are some examples of alkylating agnets?
not an obj, just to review the names in case they show up on the exam
cyclophosphamide, mechlorethamine, melphalan, chlorambucil, and thiotepa
What “ring” does DNA alkylating agents cleave to cause an icnreased risk of cancer?
guanine imidazole ring –> disruption of DNA molecular structure
What 2 things does alkylating agents create abnormal base-pairing with to cause miscoding and mutation?
Alkylated guanine and thymine
Which residue does alkylating agents excise (depurination) do ↑ the risk of cancer?
Guanine
What is the drug that is used to treat superficial bladder cancers?
Thiotepa
Can thiotepa be administered orally?
No
What is the drug that targets hypoxic tumor cells, because it required bioreductive activation, which occurs more readily in low-O2 environments?
Mitomycin
What cancer is Dacarbazine used for?
Hodgkins disease
Procarbazine is also used for Hodgkins disease, but what route of availability can it be used?
Oral
gigg. giggity
What is the enzyme that prevents permanent DNA damage by removing alkyl adducts to the O6 position of guanine before cross-links are formed?
MGMT
So if there is and ↑ expression of MGMT in neoplastic cells, what drug classes have a hard time working?
Alkylating agents
What can be damaged in normal cells from alkylating agents?
DNA
So which rapidly proliferating tissues are at risk for damage from alkylating agents?
Bone marrow
GI
Genitourinary tract epithelium
Hair follicles
Which cells does alkylating agents cause damage in, which leads to immunosuppression?
Lymphocytes
What is the drug that consists of a paltinum atom bound to 2 amines and 2 chlorines in the cis conformation?
Cisplatin
cis
What does cisplatin do to guanine residues to cause DNA damage?
forms intrastrand cross-links between adjacent guanine residues
What cancer is cisplatin used to treat?
Testicular cancer
What si teh dose-limiting toxicity for cisplatin?
Nephrotoxicity
What is the drug is synthesized by Strep, has prominent cytotoxic acitivty by binding DNA and chelated iron (II), leading to the formation of free radicles that cause single and double stranded DNA breaks?
Bleomycins
What is the major side effect of bleomycin?
Pulmonary fibrosis
What is the target of camptothecins to cause DNA strand dmg?
Topoisomerase I
What is the drug that interferes with topoisomerase II?
Anthracyclines
What is the dangerous toxicity of doxorubicin?
Heart failure
What is the protein that normally serves as an efflux pump, and can cause resistance to chemo drugs if it’s increased?
P-glycoprotein
What do vinca alkyloids, vinblastine,a nd vincristine bind to at the + end of microtubules?
Beta-tubulin
Binding to B-tubulin by the vincas prevents what to happen?
Tubulin polymerization –> no microtubule extension
What is the dose-limiting toxicity of vinblastine?
Myelosuppression
Which drugs are inhibitors of microtubule DEpolymerization?
Taxanes
paclitaxel, docetaxel
Imatinib meselate treats CML, which has shows that tumor cells are dependent on what oncogenes for their survival?
BCR-ABL
In the RAS cascade, which drugs inhibit the EGFR?
Cetruximab
In the RAS cascade, what drug directly inhibits RAS?
Farnesyltransferase inhibitors
In the RAS cascade, what inhibits the Tyr-P points on the receptor?
Gefitinib
In the RAS cascade, what does Imatinib and Dasatinib inhibit?
ABL
In the RAS cascade, which drug inhibits RAF?
Sorafenib
In the RAS cascade, MEK inhibitors block what?
MEK
lol
So to sum it up, what is the whole RAS cascade from receptor –> Myc/Jun/Fos?
EGFR –> Tyr-P –> RAS (activated by ABL and SRC) –> RAF –> MEK –> MAPK –nucleus–> MYC + JUN + FOS –> gene trasncription
Which pathway does VEGFR2 signal to promote proliferation of endothelial cells?
RAF/MAPK pathway
Which pathway does VEGFR2 signal to promote survival of endothelial cells?
PI3K/AKT
RAS is a middle man by encoding which genes, which if left on or mutated, would allow for uncontrolled growth?
GTPases
What are the main involvements of SRC, which could lead to excessive cell prolifereation if mutated and icnreased?
Survival
Angiogenesis
Proliferation
Which “chromosome” is associated with BCR-ABL?
Philadelphia chromosome t(9,22)
The Philadelphia chromosome t(9,22) is associated with which leukemia?
CML
PTEN is a tumor suppressor that blocks which pathway?
AKT/PKB
What is the syndrome where there is only 1 fxnl copy of p53, which leaves u for a big risk for tumors?
Li Fraumeni syndrome
Erlotinib reversibly binds to the ATP binding site of which receptor?
EGFR
What cancer is Erlotibib used to treat?
Metastatic non-small cell lung cancer
What is the other EGFR inhibitors but is used for EGFR expressing colorectal cancers and some head and neck tumors?
Cetuximab
What is the inhibitor of the bcr-abl tyrosine kinase found in CML leukemic cells?
Imatinib mesylate
What are the 2 reasons that dasatinib is better than imatinib?
Greater efficacy against BCR-ABL
Inhibits the activity of imatinib-resistnat BCR-ABL isoforms
FLT3 can be mutated in which leukemia?
AML
Since FLT3’s can be mutated in AML to produce ligan-independent tyrosine kinases, which drugs can demonstrate anti-leukemia cell activity?
FLT3 inhibitors
What is required for RAS for its association with the plasma membrane?
Farnesylation
What 3 cancers demonstrate K-RAS mutations?
Non-small cell lung CA
Colorectal CA
Pancreastic carcinoma
What does Sorafenib inhibit, which is downstream of RAS?
RAF
What does rapamycin bind to initially?
FKBP12
After rapamycin binds to FKBP12, what does the complex bind to, thus inhibiting its activity?
mTOR
Inhibition of mTOR promotes which processes?
Cell cycle inhibition, apoptosis, and angiogenesis inhibiton
What is Bevacizumab (IgG1 Ab) directed against?
VEGF-A
Bevacizumab is used to treat what cancer, since it typically has an overexpression of VEGF?
Metastatic renal cell carinoma
What are the 3 things that sunitinib inhibt?
VEGFR-1
VEGFR-2
PDGFR
Sorafenib inhibits everything that sunitinib inhibits, plus what other thing?
B-RAF
What is the first-line treatmnet for multiple myeloma?
Thalidomide and Dexamethasone
just FYI:
(T= the drug that causes limb deformities in feti, and D = cortisol, which determines whether cushings is from a ACTH secreting tumor or not)
What are the 2 ways that thalidomide acts against multiple myeloma?
Inhibits FGF induced angiogensis
Co-stimulate T cells
What is the anti-CD20 IgG monoclonal Ab that enchances chemotherapy effects in B-cell non-Hodgkins lymphoma?
Rituximab