L3-4: Cancer Endocrine Flashcards
3 common hormone related cancers
prostate, endometrial, and breast
17-α Hydroxylase (CYP17A1) role and location
- converts pregnenolone into 17α-hydroxypregnenolone
- converts progesterone into. 17α-hydroxyprogesterone
located primarily in adrenal glands and gonads
17,20 lyase role and location
- cleaves the 17-hydroxy intermediates made from 17α-hydroxylase into DHEA and androstenedione (both precursors to androgens and estrogens)
located in adrenal glands and gonads
what is CYP19?
aromatase
5α-reductase role in steroid hormone synthesis
convert testosterone to DHT (most active testosterone molecule)
many cancers that belong to what lineage are responsive to glucocorticoids
lymphoid lineage
corticosteroid tx can be used as palliative care in cancer to do what 3 things?
- reduce inflammation
- edema
- manage pain during chemo
corticosteroid tx can also be used to reduce hypersensitivity reactions. what are these?
Nausea
vomiting
immune-related adverse effects
hormonal cancer therapies primarily target which two things?
- estradiol (breast, endometrial
- dihydrotestosterone(DHT) (prostate)
primary hormone for prostate cancer
DHT
primary hormone for breast and endometrial cancer
estradiol
what are the 2 major strategies to endocrine therapies? (from slide 8)
- stop steroid receptor function
- decrease production of steroids
T or F:
Endocrine therapies attempt to increase the production of steroids to regulate cell growth
false, decreases production because these hormones often fuel the growth of cancers
T or F :
Estrogen receptors (ER) and progesterone receptors (PR) are both measurable in tumors
true
Well differentiated tumors are more likely to be ____
ER+
poorly differentiated tumors are generally ___
ER-
T or F:
poorly differentiated tumors have lower growth fractions and are generally more sensitive to cytotoxic agents
false, higher growth fractions
T or F:
PR is estrogen inducible and is a measure of biological response to estrogen
True, don’t know what this means so I didn’t alter it to make it false, just read it twice
T or F:
Hormone therapy in breast cancer is generally limited to ER-/PR- tumors
False, ER+/PR+
what is the difference between ER+ and ER-
ER+ = cancer cells have estrogen on their surface
ER- = cancer cells do not have estrogen on their surface
T or F:
Most breast cancers are ER-
false, most are ER+
T or F:
Hormone therapy is generally limited to ER- cancers
false, use them in ER+
Which hormone is produced in the pituitary gland?
A. GnRH
B. LH
C. estrogen
D. progesterone
B. LH
Estrogen receptor primarily binds estrogen where in the cell?
A. On the plasma membrane
B. In the mitochondria
C. In the cytoplasm
D. In the nucleus
C. Cytoplasm
What enzyme converts androstenedione to estrone?
A. CYP19
B. 5alpha-reductase
C. 17, 20 lyase
D. P450scc
A. CYP19 (aromatase)
T or F:
More differentiation leads to more cancer subtypes
True
Which of the following is a tumor suppressor?
A. HER2
B. BRCA1
C. Luminal progenitor
B. BRCA1
Which of the following is a tyrosine kinase receptor (TKR)?
A. HER2
B. BRCA1
C. Luminal progenitor
A. HER2
what treatment do you consider for basal-like and claudin-low breast tumor subtypes?
Cytotoxic agents, not hormonal
wtf does mesenchymal mean?
cells that develop into connective tissue, blood vessels, and lymphatic tissue
what are the 4 molecular subtypes in breast cancer?
- triple negative (ER-, PR-, HER2-)
- HER2+
- Luminal B
- Luminal A
Are luminal A and B more responsive to endocrine or cytotoxic therapies?
endocrine, they are typically ER+/PR+
what receptor(s) is/are expressed in Luminal B and Luminal A subtypes?
ER+/PR+ combo
what does tamoxifen get metabolized into?
4- hydroxytamoxifen (4-OH-TAM)
what enzyme metabolizes tamoxifen into 4OH-TAM?
CYP2D6
CYP___ converts tamoxifen to ______-_______ hydroxylated and demethylated metabolites
2D6, high-affinity
Binding of tamoxifen to ER will have effects on which 2 things in a tissue-specific manner *
translocation and DNA binding
T or F:
Tamoxifen has antagonist and agonist effects on estrogen
true
What are the estrogen antagonist effects from tamoxifen? (2)
- blocks estrogen-dependent breast cancer cell proliferation
- hot flashes due to anti-estrogen effects
what are the estrogen agonist effects from tamoxifen? (2)
- incidence of endometrial cancer increased 3-fold
- preservation of bone density in post-meno women (less osteoporosis)
what drug class is tamoxifen?
Selective estrogen receptor modulator (SERM)
T or F:
Tamoxifen is effective in both pre and post-meno women
true
Primary use of tamoxifen is treatment for what kind of breast cancer?
resected ER+/PR+