steroid hormone dysregulation and male reproductive health W8 Flashcards
smallest branches of uterine arteries that span the endometrium? what causes them to constrict?
spiral arteries
withdrawal of progesterone causes them to constrict
which cells proliferate in response to rising estradiol levels
endometrial stromal cells (ESCs)
when do ESCs differentiate and what do they differentiate into? what is this process called?
ESCs differentiate following ovulation (in response to progesterone)
differentiate into secretory cells
this process is called decidualisation
what accompanies inflammatory response in endometrium?
massive natural killer cell proliferation and activation
what can disturbance of endometrial receptivity cause?
endometrial functional inadequacy causing:
-implantation failure
-pregnancy loss
-gynaecological disorders
what is endometriosis?
growth of endometrial tissue outside uterus (mainly on pelvic tissue)
endometriosis features?
chronic inflammation
severe pain
infertility
pathophysiology of endometriosis?
retrograde menstruation - backward efflux of menstrual debris through fallopian tubes into pelvic cavity
inflammatory processes inhibit apoptosis of endometrial cells and promote their adhesion and proliferation
promotes angiogenesis and neurogenesis
what is endometriosis characterised by?
ER-beta overexpression and reduced PR expression
hormone-dependant female cancers - how do these occur?
endogenous and exogenous hormones drive cell proliferation. presents the opportunity for accumulation of random genetic errors
breast cancer pathophysiology?
estrogens promote proliferation of breast epithelium
estrogen signalling requires ERs (both implicated in breast cancer progression)
PR-beta signalling can also contribute to breast cancer cell proliferation in response to progesterone
endometrial cancer pathophysiology?
excess estrogens and lack of progesterone affect endometrial proliferation and cell survival.
results in increasing the risk of epithelial cell transformation/carcinogenesis
risk factors for endometrial cancer?
obesity (adipose tissue can synthesise estrogens)
HRT (with estrogen as only hormone)
breast cancer treatment with tamoxifen (partial ER agonist)
loss of progesterone (due to anovulation)
ovarian cancer pathophysiology?
transformation of surface epithelial cells, germ cells, and stromal cells.
estradiol stimulates proliferation of ovarian cancer cells
progesterone enhancers ovarian cancer cell apoptosis