Skip to main content

Home/ Dr. Goodyear/ Group items tagged receptor

Rss Feed Group items tagged

Filter: All | Bookmarks | Topics Simple Middle
1More

Estrogen receptor α and β in the normal immune system and in lymphoid maligna... - 0 views

www.sciencedirect.com/...S0303720713002207 ER estrogen receptors ER beta cancer lymphoma hormone hormones receptors
shared by Nathan Goodyear on 25 Jun 13 - No Cached
  • Nathan Goodyear on 25 Jun 13
     
    ER beta receptors have future in the treatment of cancer.  ER beta is a known growth inhibitor and this study proposes that ER beta is a means to aid lymphoma treatment.
34More

Progesterone metabolites in breast cancer - 1 views

erc.endocrinology-journals.org/...717.full progesterone metabolism tumor tumorigenesis cancer risk growth hormone hormones 5-beta-pregnanediol 5-alpha-pregnanediol 4-pregnenediol 5-alpha reductase
shared by Nathan Goodyear on 20 Feb 12 - No Cached
  • P metabolites produced within breast tissues might be independently active hormones functioning as cancer-promoting or -inhibiting regulatory agents
  • these P metabolites function as independent pro-or anti-cancer autocrine/paracrine hormones that regulate cell proliferation, adhesion, apoptosis and cytoskeletal, and other cell status molecules via novel receptors located in the cell membrane and intrinsically linked to cell signaling pathways
  • only a fraction of all breast cancer patients respond to this estrogen-based therapy and the response is only temporary
  • ...30 more annotations...
  • P serves as the precursor for the major steroid hormones (androgens, estrogens, corticosteroids) produced by the gonadal and adrenal cortical tissues.
  • 5α-pregnane, 5β-pregnane, and 4-pregnene metabolites of P
  • These P-metabolizing enzymes included 5α-reductase, 5β-reductase, 3α-hydroxysteroid oxido-reductase (3α-HSO), 3β-HSO, 20α-HSO, 20β-HSO, 6α(β)-, 11β-, 17-, and 21-hydroxylase, and C17–20-lyase
  • Reduction of P to 5α-pregnanes is catalyzed by 5α-reductase and the direct 5α-reduced metabolite of P is 5α-pregnane-3,20-dione (5αP). The 5α-reductase reaction is irreversible
  • The two 4-pregnenes resulting from direct P conversion are 4-pregnen-3α-ol-20-one (3αHP) and 4-pregnen-20α-ol-3-one (20αHP), catalyzed by the actions of 3α-HSO and 20α-HSO respectively
  • the P-metabolizing enzyme activities identified in human breast tissues and cell lines were: 5α-reductase, 3α-HSO, 3β-HSO, 20α-HSO, and 6α-hydroxylase
  • In normal breast tissue, conversion to 4-pregnenes greatly exceeded the conversion to 5α-pregnanes, whereas in tumorous tissue, conversion to 5α-pregnanes greatly exceeded that to 4-pregnenes
  • The results indicated that P 5α-reductase activity is significantly higher, whereas P 3α-HSO and 20α-HSO activities are significantly lower in tumor than in normal tissues
  • he results showed that production of 5α-pregnanes was higher and that of 4-pregnenes was lower in tumorigenic (e.g. MCF-7) than in nontumorigenic (e.g. MCF-10A) cells (Fig. 3c⇑), while differences in ER/P status did not appear to play a role
  • The 5α-pregnane-to-4-pregnene ratios were 7- to 20-fold higher in the tumorigenic than in the nontumorigenic cell lines
  • altered direction in P metabolism, and hence in metabolite ratios, was due to significantly elevated 5α-reductase and depressed 3α- and 20α-HSO activities in breast tumor tissues and tumorigenic cells. It appeared, therefore, that changes in P-metabolizing enzyme activities might be related to the shift toward mammary cell tumorigenicity and neoplasia
  • In vivo, changes in enzyme activity can result from changes in levels of the enzyme due to changes in expression of the mRNA coding for the enzyme, or from changes in the milieu in which the enzyme operates (such as temperature and pH, and concentrations of cofactors, substrates, products, competitors, ions, phospholipids, and other molecules)
  • Overall, the enzyme activity and expression studies strongly suggest that 5α-reductase stimulation and 3α- and 20α-HSO suppression are associated with the transition from normalcy to cancer of the breast
  • The level of expression of 5α-reductase is up-regulated by estradiol and P in the uterus (Minjarez et al. 2001) and by 5α-dihydrotestosterone (DHT) in the prostate
  • 3αHP inhibited whereas 5αP-stimulated proliferation
  • Stimulation in cell numbers was also observed when cells were treated with other 5α-pregnanes, such as 5α-pregnan-3α-ol-20-one, 5α-pregnan-20α-ol-3-one, and 5α-pregnane-3α,20α-diol, whereas other 4-pregnenes such as 20α-HP and 4-pregnene-3α,20α-diol resulted in suppression of cell proliferation
  • Stimulation of cell proliferation with 5αP and inhibition with 3αHP were also observed in all other breast cell lines examined, whether ER/P-negative (MCF-10A, MDA-MB-231) or ER/P-positive (T47D, ZR-75-1) and whether requiring estrogen for tumorigenicity (MCF-7, T47D) or not (MDA-MB-231), or whether they are nontumorigenic (
  • αHP resulted in significant increases in apoptosis and decreases in mitosis, leading to significant decreases in total cell numbers. In contrast, treatment with 5αP resulted in decreases in apoptosis and increases in mitosis.
  • The opposing actions of 5αP and 3αHP on both cell anchorage and proliferation strengthen the hypothesis that the direction of P metabolism in vivo toward higher 5α-pregnane and lower 4-pregnene concentrations could promote breast neoplasia and lead to malignancy.
  • he effects on proliferation and adhesion were not due to P, but due to the 5α-reduced metabolites
  • The studies showed that binding of 5αP or 3αHP occurs in the plasma membrane fractions, but not in the nuclear or cytosolic compartments
  • separate high-specificity, high-affinity, low- capacity receptors for 5αP and 3αHP that are distinct from each other and from the well-studied nuclear/cytosolic P, estrogen, and androgen and corticosteroid receptors
  • The studies thus provided the first demonstration of the existence of specific P metabolite receptors
  • the receptor results suggest that the putative tumorigenic actions of 5αP may be significantly augmented by the estradiol-induced increases in 5αP binding and decreases in 3αHP binding.
  • Estradiol and 5αP resulted in significant dose-dependent increases, whereas 3αHP and 20αHP each resulted in dose-dependent decreases in total ER
  • In combination, estradiol + 5αP or 3αHP + 20αHP resulted in additive increases or decreases respectively in ER numbers.
  • The data suggest that the action of 5αP on breast cancer cells involves modulation of the MAPK signaling pathway
  • current evidence does not appear to support the notion that increased 5α-reductase activity/ expression might significantly alter androgen influences on breast tumor growth.
  • both testosterone and DHT inhibit cell growth more or less to the same extent
  • Note that 5α-reductase reaction is not reversible
  • Nathan Goodyear on 20 Feb 12
     
    Fantastic read on the effects of progesterone metabolism on tumor and cancer growth.  Tumorigenesis is not just about the hormone, hormone balance, but about the metabolism of hormones.  This is why premarin is so carcinogenic: it is primarily metabolized by the 4-OH estrone pathway.
1More

Toll-Like Receptor-4 Mediates Vascular Inflammation and Insulin Resistance in Diet-Indu... - 0 views

circres.ahajournals.org/...1589.short inflammation insulin resistance obesity FFA saturated fat TLR4 NF-kappaB IKK-Beta
shared by Nathan Goodyear on 21 Dec 11 - No Cached
  • Nathan Goodyear on 21 Dec 11
     
    high saturated fat intake (excess FFA) shown to contribute to obesity through TLR4 receptors.  TLR4 receptors are mediators in the innate immunity.   The result will be both IKK-Beta and NF-KappaB.
1More

Estrogen Receptor-Related Receptor α Mediates Up-Regulation of Aromatase Expr... - 0 views

mend.endojournals.org/...1175.abstract ER-alpha estrogen receptors aromatase prostate men male PGE2 hormone hormones
shared by Nathan Goodyear on 18 Sep 12 - No Cached
  • Nathan Goodyear on 18 Sep 12
     
    ER alpha increases aromatase expression in the prostate.  PGE2 increased the ER alpha receptor.  Vicious cycle in men.  Increased aromatase activity increases estrogen production which increases ER alpha (pro growth) and further aromatase activity.
1More

The androgen metabolite 5alpha-androstane-3beta,17beta-diol (3betaAdiol) induces breast... - 0 views

www.researchgate.net/...aromatase_inhibitor_resistance breast cancer aromatase aromatase inhibitors estradiol estrogen 3-beta androstanediol Testosterone DHT 3 beta HSD receptor receptors ER alpha ER-alpha ER beta ER-beta hormone hormones women
shared by Nathan Goodyear on 21 Jan 14 - No Cached
  • Nathan Goodyear on 21 Jan 14
     
    Great article!!  Nice discussion of the complexity of hormones.  Women on aromatase inhibitors can make estrogen from Testosterone.  This is important with estrogen sensitive cancer as in breast cancer.  This will occur via alternative pathways: Testosterone to DHT via 5 alpha reductase and then DHT to 3 beta androstanediol via 3 beta HSD.  3 beta androstanediol is a male hormone metabolite that binds to estrogen receptors.  The affinity is less than Estradiol, but appears to have a higher affinity for ER beta over ER alpha. 
1More

Breast Cancer Research | Full text | Progesterone metabolites regulate induction, growt... - 0 views

breast-cancer-research.com/...R38 breast cancer progesterone metabolite metabolites 5-alpha-pregnanediol 4-pregnene
shared by Nathan Goodyear on 23 Jan 14 - No Cached
  • Nathan Goodyear on 23 Jan 14
     
    5alpha pregnanes and 4 pregnanes stimulate ER and PR negative breast cancer cells.  Progesterone metabolites stimulate or inhibit cancer potential independent of receptor status.  Though we know that progesterone metabolite balance can increase receptor binding.
1More

The Estrogen Receptor β Subtype: A Novel Mediator of Estrogen Action in Neuro... - 0 views

www.sciencedirect.com/...S0091302298901704 Estrogen receptors receptor ER alpha ER-alpha ER beta ER-beta hormone hormones
shared by Nathan Goodyear on 27 Jan 14 - No Cached
  • Nathan Goodyear on 27 Jan 14
     
    Estrogen receptors are one mechanism of the transmission of the estrogen signal.  The signal can be from estrogens themselves, estrogenic like compounds (xenoestrogens) and via non-estrogens like 3-beta androstane idol that interacts with ER beta to decrease prostate cancer cell proliferation.
8More

The Androgen Derivative 5α-Androstane-3β,17β-Diol Inhibits Prostate Cancer Ce... - 0 views

cancerres.aacrjournals.org/...5445.full prostate cancer 3-beta androstanediol DHT metabolite E-cadherin ER beta ER-beta male hormone hormones men
shared by Nathan Goodyear on 27 Jan 14 - No Cached
  • In the early stages, prostate cancer growth is dependent on circulating androgens
    • Nathan Goodyear
      Nathan Goodyear on 27 Jan 14
       
      This is in contrast to studies that show poor prognosis with Lower T at time of diagnosis of prostate cancer
  • 5α-reductase not only provides a potent amplification of the androgenic signal ( 4– 6), but it also prevents estrogen formation by subtracting testosterone from the action of aromatase ( 7, 8), thus blocking activation of the estrogen receptor subtypes (ERα and ERβ; refs. 9, 10)
  • ERβ is the prevailing subtype ( 11), and a growing body of evidence points to the protective role of this receptor in prostate cancer
  • ...3 more annotations...
  • It has been shown that the transformation of the dihydrotestosterone to 5α-androstane-3α,17β-diol (3α-diol) and 5α-androstane-3β,17β-diol (3β-Adiol), generates two metabolites unable to bind the androgen receptor, but possessing a very high affinity for the estrogen receptors
  • the effects of testosterone may result from the balance between the androgenic and the estrogenic molecules originating from its catabolism.
  • Recent data have been published postulating a direct estrogenic role of the 3β-hydroxylated derivatives of dihydrotestosterone in the prostate development and homeostasis
  • Nathan Goodyear on 27 Jan 14
     
    Here is the full article.
1More

Revisiting the roles of progesterone and allo... [Prog Neurobiol. 2014] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...24172649 progesterone metabolites metabolite allopregnanolone GABA receptors PR brain
shared by Nathan Goodyear on 17 Mar 14 - No Cached
  • Nathan Goodyear on 17 Mar 14
     
    Only the abstract is available, but this study looks at the effects of progesterone through progesterone receptors and the progesterone metabolite allopregnanolone via the GABA A receptors in the brain.
1More

Effects of 3-beta-diol, an androgen metabolite with intrinsic estrogen-like effects, in... - 0 views

www.biomedcentral.com/...1477-7827-4-51.pdf 5-beta androstanediol androgen metabolites ER beta ER-beta estrogen receptors ER
shared by Nathan Goodyear on 06 Jul 13 - No Cached
  • Nathan Goodyear on 06 Jul 13
     
    5-beta androstanediol doesn't have affinity for androgen receptors, but for estrogen receptors. Affinity for ER beta exceeds that for ER alpha.
1More

Organophosphate Antagonism of the Androgen Receptor - 0 views

toxsci.oxfordjournals.org/...1.full organophosphates insecticides xenoestrogen androgen receptor antagonists androgen receptor antagonist antagonists
shared by Nathan Goodyear on 17 Jul 13 - No Cached
  • Nathan Goodyear on 17 Jul 13
     
    Organophosphates are androgen receptor antagonists. Organophosphates are xenoestrogens.
1More

Clinicopathological and molecular characterizatio... [Mod Pathol. 2011] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...21358618 progesterone estrogen receptors papillary thyroid cancer
shared by Nathan Goodyear on 25 Nov 13 - No Cached
  • Nathan Goodyear on 25 Nov 13
     
    Though nuclear expression of estrogen and progesterone receptors were increased in papillary cancer, only progesterone receptor expression was decreased in aggressive cancer.
1More

Membrane 5α-pregnane-3,20-dione (5αP) receptors in MCF-7 and MCF-10A breast c... - 0 views

www.sciencedirect.com/...S0960076005003420 breast cancer progesterone metabolites progesterone metabolites hormone hormones
shared by Nathan Goodyear on 18 Jun 14 - No Cached
  • Nathan Goodyear on 18 Jun 14
     
    Very interesting study.  In ER/PR + breast cancer cells, Estradiol and 5alpha-dihydroprogestorone increase the membrane expression of 5alpha-dihydroprogesterone receptors.  This has a pro-growth, pro-metastatic potential.  In contrast, the metabolites 3alpha-dihdroprogesterone and 20alpha-HP inhibit the same membrane receptor expression thus giving an antigrowth, anti-metastatic potential.
1More

Toll-like receptors in innate immunity - 0 views

intimm.oxfordjournals.org/...1.full Toll-like receptors Toll-like receptors TLRs innate immune system immunity
shared by Nathan Goodyear on 15 Jun 14 - No Cached
  • Nathan Goodyear on 15 Jun 14
     
    Great review of Toll-like receptors.
1More

Immunohistochemical Expression of Estrogen and Progesterone Receptors in Human Colorect... - 0 views

www.ncbi.nlm.nih.gov/...PMC3215447 estrogen progesterone ER estrogen receptor estrogen receptors ER alpha ER beta ER-alpha ER-beta PR progesterone receptor progesterone receptors
shared by Nathan Goodyear on 09 Jun 14 - No Cached
  • Nathan Goodyear on 09 Jun 14
     
    Study finds ER and PR increase along the timeline of tumor initiation.  The authors point to likely association that ER and PR expression is associated with and key to initiating colorectal transformation.  A lot to be determined from this study.  IF this were entirely true, then what to explain the 35% lower colorectal cancer risk in women vs men?  Likely ER and PR pertubance plays a significant role is likely, but the mere expression--yet to be determined.
1More

New aspects of cadmium as endocrine disruptor. [Environ Sci. 2006] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...16788562 cadmium heavy metals hormones estrogen receptors androgen endocrine disrupting chemicals endocrine disruptors puberty
shared by Nathan Goodyear on 20 Jul 14 - No Cached
  • Nathan Goodyear on 20 Jul 14
     
    Cadmium is an endocrine disruptor: binds to estrogen receptors and the androgen receptor. 
2More

Insulin Receptor Expression and Function in Human Breast Cancer Cell Lines - Cancer Res - 0 views

cancerres.aacrjournals.org/...3924.short insulin breast cancer receptors
shared by Nathan Goodyear on 11 Dec 10 - No Cached
  • This present study indicates therefore that in breast cancer cell lines there are functional insulin receptors that regulate breast cancer cell growth.
  • Nathan Goodyear on 11 Dec 10
     
    breast cancer cells express high functioning insulin receptors
1More

A novel perspective for Alzheimer's disease... [J Alzheimers Dis. 2011] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...20966550 alzheimer disease alzheimers amyloid-beta vitamin D vitamin d VDR receptor
shared by Nathan Goodyear on 04 Jun 14 - No Cached
  • Nathan Goodyear on 04 Jun 14
     
    Alzheimer's model finds that amyloid-beta supresses vitamin D receptor.  This study found that vitamin D therapy protected neurons by up regulating vitamin D receptors.  This prevented cytotoxicity and cell death.
1More

Androgen receptor expression is inversely correlated with pathologic tumor stage in bla... - 0 views

www.goldjournal.net/...abstract androgen receptor androgen receptors bladder cancer bladder cancer men male hormone hormones AR
shared by Nathan Goodyear on 04 Jan 15 - No Cached
  • Nathan Goodyear on 04 Jan 15
     
    Study finds that loss of Androgen receptors associated with advanced stage bladder cancer in men.
1More

Androgen Receptor Is a Potential Therapeutic Target for Bladder Cancer - Urology - 0 views

www.goldjournal.net/...fulltext AR androgen receptor androgen receptors bladder cancer bladder cancer male men hormone hormones
shared by Nathan Goodyear on 04 Jan 15 - No Cached
  • Nathan Goodyear on 04 Jan 15
     
    Study finds that a decrease in androgen receptor inhibits bladder cancer cell growth in vivo and in vitro studies.  
« First ‹ Previous 81 - 100 of 700 Next › Last »
Showing 20▼ items per page