Kinase inhibitors Flashcards
What is unique about the action of the Tamoxifen as compared to Fluvestrant?
a. It leads to ER degradation
b. It holds ER out of the nucleus
c. It ejects ER from the cell
d. It activates ER in bone
d. It activates ER in bone
Fluvestrant degrades ER
Which of the following is not a hormone responsive cancer type?
a. Breast cancer
b. Ovarian cancer
c. Prostate Cancer
d. Endometrial cancer
d. Endometrial cancer
Which of the following is only used in the postmenopausal setting?
a. Letrozole
b. Tamoxifen
c. Leuprolide
d. Raloxifene
a. Letrozole
Which compound acts directly on AR?
a. Leuprolide
b. Abiraterone
c. Degarelix
d. Enzalutamide
d. Enzalutamide
signal transduction through _______ drives proliferation in cancer
kinases
kinases work on ________ factors which change genes
transcription
there are __#___ human kinases & more than ___#__ genes encoding potential kinases
There are currently __#__ approved kinase inhibitors all with a diverse structure
518; 900
~81
kinase inhibitors require _____ to guide their application.
what are the 2 main driver mutations in lung cancer
biomarkers
EGFR & KRAS
Diagnostic Molecular pathology:
Genomic ____from lung cancer biopsies are tested via PCR for a particular mutation of _____.
If positive these patients will go on anti-_____ therapies.
DNA; EGFR; EGFR
EGFR= epidermal growth factor
cell signaling is largely driven by the transfer of ___________
phosphates
what is the major source of the phosphate group that is transferred by a kinase to a target protein?
Adenosine triphosphate (ATP)
__________ is a common target of several kinases.
______ + __________+ _________ can also be phosphorylated. This leads to dimerization and cascade
tyrosine
serine. threonine, lipids
______ are prime targets for small molecule inhibitors
kinases
kinases are generally made up of __ and ____ lobes connected by a hinge region.
an _______ loop controls controls access to the active site
N & C lobes
activation
Type I inhibitors bind to the ________conformation of the kinase.
Type II inhibitors bind and stabilize the ______conformation of the kinase.
Type III inhibitors occupy an ______pocket outside of the ATP-binding pocket.
active
inactive
allosteric
Competitive Inhibitors bind kinase in a __reversible/irreversible__ fashion and therefore must compete with ATP for binding.
reversible
________Inhibitors tend to covalently bind with a reactive nucleophilic _______residue proximal to the ATP-binding site, resulting in the blockage of the ATP site and
_______ inhibition.
covalent; cysteine residue; irreversible
Which amino acid is not a target of phosphorylation?
a. Tyrosine
b. Serine
c. Threonine
d. Alanine
d. Alanine
only has a methyl group
What is the source of the phosphate the gets transferred onto a substrate by a kinase?
a. SAM
b. DNA
c. RNA
d. ATP
d. ATP
EGFR targeted kinase inhibitors
-Mutations in EGFR cause the receptor to be constitutively ___inactivated/activated___.
-Patients with these mutations show an enhanced response to EGFR inhibitors.
activated
what is the main Type 1 (EGFR) targeted kinase inhibitor? what type of cancer is it used to treat
Gefitinib
>largely being replaced by more favorable covalent inhibitors (Afatinib and Neratinib)
EGFR-mutant metastatic NSCLC
Gefitinib (IRESSA - EGFR kinase inhibitor)
> EGFR signaling induces cell proliferation
> EGFR is __under/over___expressed and has higher signaling activity in __%___ of human cancers
> EGFR overexpression correlates with poor prognosis
> Erlotinib is a small molecule __reversible/irreversible__inhibitor of EGFR tyrosine kinase
-Competitively inhibits the enzyme by binding to the ____ binding site in the kinase domain
-Inhibition of kinase activity turns off signal to proliferate
> Gefitinib and Erlotinib are approved for treatment of patients with __________ cancer whose tumors have EGFR exon ____ or _____mutations.
> Drugs are well tolerated – most adverse effects (fatigue, rash, diarrhea).
over; 25-50%
reversible; ATP
metastatic non-small cell lung cancer (NSCLC)
19 or exon 21 (L858R)
afatinib (gilotrif) is a _________ inhibitor of all ___ receptors
tx of _____________ cancer with EGFR mutations
covalent; ErbB
EGFR mutant Non-small cell lung cancer (NSCLC)
> Dacomitinib also a covalent inhibitor approved for non-resistant EGFR mutant lung cancer.
t/f EGFR inhibitor-associated skin rash is normal
true, it means it’s working and pt is more likely to respond to inhibitor
NEED TO KNOW THIS SIDE EFFECT
EGFR inhibitors = RASH
_____ causes resistancce to Geftinib.
______ is used in pts with this mutation
Osimertinib
Osimertinib is a _____ generation EGFR inhibitor. It is a ________ kinase inhibitor.
new reports of ______mutation that abrogates binding –> osimertinib no longer effective
third; covalent; C797
Are EGFR inhibitors curative?
no, pt will be taking them forever