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Nathan Goodyear

Androgens and prostate disease Cooper LA, Page ST - Asian J Androl - 0 views

www.ajandrology.com/article.asp

prostate disease cancer Testosterone DHT 5-alpha reductase men male hormone hormones

shared by Nathan Goodyear on 15 Jan 14 - No Cached
  • intraprostatic androgens are not concomitantly increased when serum androgen levels are raised.
  • The "saturation model" proposes that the prostate is sensitive to very low concentrations of circulating androgens, but that once maximal AR binding is achieved, which occurs at relatively low concentrations of circulating T, further increases in serum T have little impact
  • men with metastatic prostate cancer given T who had been previously treated with castration had worsening of disease, whereas those without prior castration did not
  • ...3 more annotations...
  • There is little data to support the withholding of T therapy on the basis of concern for precipitating prostate cancer.
  • Both intervention data and physiology studies point to minimal effects on the prostate gland when serum T levels are increased to the mid-normal range with T therapy
  • an individualized care plan to assess the possible risks and benefits of T therapy for each patient is critical to optimizing the use of androgens in male health.
  • Nathan Goodyear on 15 Jan 14
     
    Nice review of the mixed data on Testosterone and Prostate disease. It is clear that Testosterone does not precipitate prostate cancer.  The intraprostatic hormone milieu likely is different than that present in the serum.  No surprise there.  5alpha reductase decreases prostate volume, PSA, and low-grade prostate cancer, but actually increases aggressive prostate cancer. Supraphysiologic doping in young men associated with no increase in prostate disease. PSA no longer to be followed in men < 55.  Mortality rate not changed.  PSA change of 1.4 ng/ml is appropriate for additional prostate evaluation.  Testosterone therapy on average increased 0.5 ng/ml. Still, no mention of aromatase activity in this article.  Why is it that hormone sensitive disease in men is only with regards to androgens and women estrogen.
Nathan Goodyear

Bisphenol A Promotes Human Prostate Stem-Progenitor Cell Self-Renewal and Increases In ... - 0 views

www.ncbi.nlm.nih.gov/...PMC3929731

BPA bisphenol A cancer prostate cancer prostate xenoestrogens

shared by Nathan Goodyear on 20 Apr 16 - No Cached
  • these findings show that estrogen stimulates human prostate epithelial stem cell self-renewal and progenitor cell amplification (prostasphere size), with the greatest effects observed at lower E2 doses.
  • Similar to E2, BPA increased prostasphere number and size with significant and maximal effects observed at 10 nM BPA
  • Taken together, these results provide strong evidence that, similar to E2, BPA increases stem cell self-renewal and progenitor amplification in normal human prostate epithelial cells
  • ...13 more annotations...
  • these findings provide further support that E2 and BPA maintain the stem-like state within the normal prostate epithelial cell population
  • Our previous findings demonstrated that normal prostate stem-progenitor cells within the prostaspheres expressed ERα and ERβ, implicating them as direct targets for E2 and BPA action
  • p-Akt and p-Erk, well established downstream targets of membrane-associated ERs
  • BPA and E2 had equimolar capacity for activation of these rapid signaling pathways in human prostaspheres, thus identifying a dynamic and robust signaling pathway initiated by low-dose BPA exposure in prostate stem-progenitor cells.
  • these findings indicate that both rapid membrane-initiated estrogen action and genomic ER signaling pathways are operative in human prostate progenitor cells.
  • these results document the fact that levels of bioactive BPA in the present study are similar to levels found in human umbilical cord blood and newborns in the general population
  • the present findings identify for the first time that in vivo exposure of the human prostate epithelium to low doses of BPA significantly increases the susceptibility of the human prostate epithelium to hormonal carcinogenesis.
  • The current study provides clear evidence that, similar to E2, normal human prostate stem and progenitor cells are direct targets for BPA action
  • Both hormones increased stem-like cell numbers in primary prostate epithelial cultures in a dose-dependent manner and augmented the number and size of 3-D cultured prostaspheres, markers of stem cell self-renewal and progenitor cell proliferation, respectively
  • signaling pathways engaged by estrogens through these separate receptors are multiple and complex, including both membrane-initiated signaling and genomic activation via ER transcriptional activity
  • Estrogen action is mediated by ERα and ERβ
  • the current results indicate that developmental exposure to BPA, at doses routinely found in humans, significantly increases the cancer risk in human prostate epithelium in response to elevated estrogen levels in an androgen-supported milieu. Because relative estrogen levels rise in aging men, we suggest that humans may be susceptible to BPA-driven prostate disease in a manner similar to that in the rodent models.
  • We propose that early-life perturbations in estrogen signaling including inappropriate exposure to BPA have the potential to amplify and modify the stem-progenitor cell populations within the human prostate gland and, in so doing, alter the normal homeostatic mechanisms that maintain a growth neutral state throughout life
  • Nathan Goodyear on 20 Apr 16
     
    Bisphenol A exposure in utero found to increase prostate cancer risk later in life.  This exposure occurred at typical life exposure levels as found in umbilical cord blood sampling,  This occurred through stem cell self-renewal and progenitor amplification
Nathan Goodyear

Androgen deprivation promotes intratumoral synthesis of dihydrotestosterone from androg... - 0 views

www.nature.com/...srep01528.html

prostate cancer 3-alpha androstanediol 3-beta androstanediol DHT metabolite metabolites

shared by Nathan Goodyear on 27 Jan 14 - No Cached
  • PSA levels in media were increased by 3α-diol
  • Similarly to 3α-diol, 3β-diol also increased PSA levels in media in a concentration-dependent manner
  • intracellular DHT is synthesized from inactive androgen 3α- and 3β-diol via different pathways in prostate cancer cells
  • ...12 more annotations...
    • Nathan Goodyear
      Nathan Goodyear on 15 Jul 15
       
      error in statement: DHT metabolites are not inactive, they just don't activate AR.
  • 3β-diol can be a precursor of DHT in prostate cancer cells.
  • serum 3α-diol G levels reflect the androgen milieu in localized prostate cancer patients receiving ADT
  • A few studies reported that 3β-diol is a potential ligand of estrogen receptor β (ERβ) and has an antiproliferative effect
  • our results revealed that 3β-diol is potentially a precursor of DHT in prostate cancer cells
  • Bauman et al. showed that 3α-diol is inactive at AR, but induces prostate growth
  • Prostate cancer cells promoted synthesis from the DHT metabolite 3α-diol during the long duration of ADT
    • Nathan Goodyear
      Nathan Goodyear on 15 Jul 15
       
      the authors highlight the suggestion is that 3alpha-diol's activity is via 3alpha-HSD, but fail to mention that it is known that 3alpha-diol interacts with the ER-alpha in the prostate.
  • verified the synthesis of DHT from 3α- or 3β-diol via different pathways in prostate cancer cells in this study
  • HSD17B6 expression levels in prostate cancer can be useful for the diagnosis of high-risk prostate cancer
  • serum 3α-diol G levels reflect the adrenal androgen milieu in localized prostate cancer patients
  • 3α- and 3β-diol has a much more significant role in intratumoral androgen metabolism during ADT
  • Nathan Goodyear on 27 Jan 14
     
    DHT metabolites play an important role of intra-prostate DHT synthesis in those following ADT.  This is a proposed mechanism for the failure rate and aggressive nature of prostate cancer that fails ADT.   3-alpha androstanediol is converted via 3 alpha HSD back to DHT.  In contrast, 3-beta androstanediol cannot.
Nathan Goodyear

An endocrine pathway in the prostate, ERβ, AR, 5α-androstane-3β,17β-diol, and... - 0 views

www.pnas.org/...13589.full

3-beta androstanediol DHT metabolite prostate cancer ER-beta ER beta CYP7b1 cytochrome male hormone hormones men

shared by Nathan Goodyear on 27 Jan 14 - No Cached
  • Although the prostate is an androgen-dependent tissue, estrogens influence both normal functions and pathological changes in this gland
  • This dual action may be due to the existence of two estrogen receptors, ERα and ERβ
  • ERα and ERβ have similar affinities for estradiol-17β
  • ...6 more annotations...
  • In this study we have shown that regulation of the levels of 3βAdiol by CYP7B1 is a key factor in regulation of prostatic growth
  • We provide evidence that proliferating cells in the prostate epithelium have elevated levels of AR and that AR protein but not mRNA levels are regulated by ERβ and its ligand 3βAdiol in the prostate epithelium.
  • because inhibition of 5α-reductase causes accumulation of testosterone and removal of ERβ action increases the level of AR in the prostate, the overall effect of Finasteride would be to favor proliferation of the prostate epithelium
  • studies show that ERβ tends to be lost in advanced prostate cancer.
  • DHEA is converted in the body to 5-androstene-3β,17β-diol, which is also a ligand for estrogen receptors (25, 39) and a substrate for CYP7B1
  • At the peak of proliferation, the proliferating epithelial cells in the ventral prostate expressed high levels of CYP7B1 but had no detectable ERβ, whereas in nonproliferating cells the level of ERβ was high and that of CYP7B1 was low.
  • Nathan Goodyear on 27 Jan 14
     
    3-beta androstanediola, a product of 3alpha-HSD from DHT binds to ER beta and down regulates AR in prostate cancer.  This study proposes that the mechanism is via CYP7B1.  CYP7B1 inactivates 3-beta androstanediol.  Interesting, because 3-beta androstanediol is considered "inactive" when compared to 3-alpha androstanediol and its interaction with ER alpha.  
Nathan Goodyear

Elderly men over 65 years of age with late-onset hypogonadism benefit as much from test... - 0 views

www.ncbi.nlm.nih.gov/...PMC4392031

low T low Testosterone Testosterone men male hormone hormones late onset hypogonadism hypogonadism

shared by Nathan Goodyear on 21 May 15 - No Cached
  • The benefits of restoring serum testosterone in men with LOH were not significantly different between men older than 65 years of age and younger men. There were no indications that side effects were more severe in elderly men. The effects on prostate and urinary function and hematocrit were within safe margins.
  • obesity, but also impaired general health, are the more common causes of low testosterone in aging men
  • Severe LOH is associated with substantially higher risks of all-cause and cardiovascular mortality,
  • ...30 more annotations...
  • advanced age, obesity, a diagnosis of metabolic syndrome, and poor general health status were predictors of LOH
  • Diabetes mellitus was correlated with hypogonadism in most studies
  • coronary heart disease, hypertension, stroke, and peripheral arterial disease did not predict hypogonadism, they did correlate with the incidence of low testosterone
  • LOH can be defined by the presence of at least three sexual symptoms associated with a total testosterone level of less than 11 nmol/L (3.2 ng/mL) and a free testosterone level of less than 220 pmol/L (64 pg/mL)
    • Nathan Goodyear
      Nathan Goodyear on 27 May 15
       
      the European Male Aging study defined low T as total < 320 ng/dl and free < 64 pg/ml.  
  • Mean weight decreased
  • Waist circumference decreased
  • Total cholesterol decreased
  • Low-density lipoprotein decreased
  • Triglycerides decreased
  • High-density lipoprotein (HDL) increased
  • ratio of total cholesterol to HDL improved
  • Prostate volume increased
  • PSA increased
  • The benefits for men older than 65 years of age were compared with those of younger men, and the improvements in body weight, metabolic factors, psychological functioning, and sexual functioning were of the same magnitude in both age groups
  • weight loss was progressive over the 6-year period, effects of testosterone on lipids and on psychological and sexual functioning reached a plateau after approximately 3 years and these effects were sustained
  • Effects of testosterone on hematopoiesis, on the prostate, and on bladder function were not more severe in older men than in younger men
  • observe a mild increase in prostate volume and serum PSA over time, which is a normal finding in aging men. Maybe somewhat surprising, postvoiding residue and the IPSS did not deteriorate with aging but showed a degree of improvement
  • the severity of the metabolic syndrome is associated with the severity of lower urinary tract symptoms
  • The symptoms of the metabolic syndrome improve upon testosterone treatment and testosterone may thus have a favorable effect on lower urinary tract symptoms
  • it seems reasonable to conclude that the risks of testosterone administration to elderly men are not disproportionately higher in elderly men than in younger men.
  • Despite evidence to the contrary, physicians still harbor a wrongful association between testosterone and the development of prostate pathology (prostate cancer and benign prostate hyperplasia)
  • Not surprisingly, the incidence of prostate cancer was higher in older men; however, it was lower than expected in both groups
  • These observations suggest that the incidence of prostate cancer in patients receiving testosterone therapy, both in the younger and in the older group, was not greater than in the general population not receiving testosterone treatment
  • The historical fear that raising testosterone levels will result in more prostate cancer has been dispelled, particularly by the work of Abraham Morgentaler
  • Higher serum testosterone levels fail to show an increased risk of prostate cancer, and supraphysiological testosterone does not increase prostate volume or PSA in healthy men
  • This apparent paradox is explained by the "saturation model,"
  • Recent studies indicate no increased risk of prostate cancer among men with serum testosterone in the therapeutic range
  • In the present observational study, no cases of major adverse cardiovascular events occurred.
  • the benefits of testosterone therapy are fully achieved only by long-term treatment
  • To achieve maximal benefits, good patient adherence is a prerequisite
  • Nathan Goodyear on 21 May 15
     
    Study finds new difference in Testosterone benefits and/or side effects between men < 65 with low T and men > 65 with low T.
Nathan Goodyear

Testosterone and benign prostatic hyperplasia Jarvis TR, Chughtai B, Kaplan SA, - Asian... - 0 views

www.ajandrology.com/preprintarticle.asp

Testosterone BPH low T low Testosterone prostate cancer men male hormone hormones

shared by Nathan Goodyear on 01 Dec 14 - No Cached
  • The prevalence of hypogonadism (often defined as serum testosterone &lt; 300 ng dl−1 ) ranges from 6% [10] to as high as 38%
  • The process of BPH, however, continues as men age and despite the fact their serum testosterone decreases
  • Liu et al. [12] demonstrated that in a group of older males (mean age 59.8 years) that there was not a significant correlation of serum testosterone levels (total, free or bioavailable) with either prostate volume or International Prostate Symptom Score (IPSS)
  • ...11 more annotations...
  • in eugonadal men, studies have demonstrated that the prostate can increase in volume by approximately 12%
  • There seems to be little doubt that the treatment with testosterone of a young hypogonadal male leads to significant growth of the prostate
  • Behre et al. [22] demonstrated increased prostate volume and prostate-specific antigen (PSA) levels in hypogonadal men
  • Most studies, however, have shown no effect of exogenous androgens on PSA or prostate volume for older hypogonadal males
  • saturation model
  • They argue that the prostate is relatively insensitive to changes in androgen concentration at normal levels or in mild hypogonadism because the AR is saturated by androgens and therefore maximal androgen-AR binding is achieved. Conversely, the prostate is very sensitive to changes in androgen levels when testosterone is low
  • visceral obesity (one of the most significant components of metabolic syndrome) is associated with prostate volume and influences prostate growth during TRT.
  • This hypothesis of inflammation induced LUTS is also argued to be a mechanism for improvement of LUTS with PDE5I
  • The concept, therefore, that treatment with TRT of hypogonadal males with metabolic syndrome might lead to improvement/stabilization of their LUTS, appears to be confirmed in recent work by Francomano et al.
  • There was also an improvement in components of the patient's metabolic syndrome (such as BMI, waist circumference, hemoglobin A1c [HbA1c], insulin sensitivity, and lipid profile) as well as inflammatory markers and C-reactive protein.
  • They concluded that TRT was safe in this group of men, and hypothesize that TRT mitigates the pro-inflammatory factors associated with metabolic syndrome.
  • Nathan Goodyear on 01 Dec 14
     
    Authors review the literature behind Testosterone and BPH.  The authors highlight the 4 proposed theories behind BPH: Testosterone, Estrogen, inflammation, and metabolic.   The conclusion is mixed: pointing out that no high level of evidence exists on either side of the debate of Testosterone and BPH.
Nathan Goodyear

Differential Effects of Dehydroepiandrosterone and Testosterone in Prostate and Colon C... - 0 views

press.endocrine.org/...en.2012-2249

testosterone prostate colon colon cancer cancer NGF nerve growth factor dhea dehydroepiandrosterone

shared by Nathan Goodyear on 19 Nov 14 - No Cached
  • Several studies indicate that DHEA may enhance cancer-promoting activities in several prostate cancer cell lines acting as agonist or antagonist for the intracellular AR
  • the estrogenic metabolites of DHEA, 5a-androstane-3b, 17b-diol (3b-Adiol) and E2 bind to estrogen receptors but not to AR
  • no specific receptor has been identified for DHEA
  • ...16 more annotations...
  • Different members of neurotrophins are expressed during cancer progression, suggesting their involvement in cell proliferation, anoikis protection, and malignancy
  • Regulation of the apoptotic machinery in prostate and colon cancer cells by testosterone occurs rapidly and is initiated at the plasma membrane level through specific membrane-binding sites not involving the classical cytoplasmic AR
  • testosterone exerts potent regulatory effects on prostate and colon cancer cell apoptosis
  • Testosterone increased cell death in a dose-dependent manner
  • testosterone antagonizes the prosurvival effects of DHEA in neuronal cells, blocking its binding to NGF receptors
  • treatment of cells with DHEA exerted a strong antiapoptotic effect,
  • Androgens hold a central role in prostate and colon cancer biology
  • elevated levels of DHEA or its sulfate ester DHEA-sulfate in young adults are associated to low incidence of androgen-dependent tumors
  • DHEA may play a protective role in young prostate
  • The decline of DHEA with aging may contribute to prostate cancer progression associated with advanced age
  • DHEA is an effective antiapoptotic factor, reversing the serum deprivation-induced apoptosis in prostate cancer cells (DU145 and LNCaP cell lines) as well as in colon cancer cells
  • NGF appears to exert similar antiapoptotic actions in both prostate and color cancer cells
  • exposure of prostate DU145 and colon Caco2 cancer cells to testosterone totally blocked the protective effects of both DHEA and NGF. These findings suggest that testosterone acts as an antagonist of DHEA and NGF
  • These findings support the hypothesis that testosterone may inhibit cancer cell growth by antagonizing the proliferative, antiapoptotic effects of endogenous factors, such as DHEA or NGF, in the case of prostate and colon cancer cells
  • intratumor hormonal microenvironment may play a critical role in tumor progression.
  • The paracrine interactions of androgens with locally produced NGF may define tumor cell fate
  • Nathan Goodyear on 19 Nov 14
     
    Full article of previously posted abstract.  Cancers are unique.  Not all cancers are alike.  Whether they are tissue specific or not, cancers are unique.  This article describes the uniqueness of DHEA and Testosterone cancer, with particular attention to colon.
Nathan Goodyear

http://www.europeanurology.com/article/S0302-2838(08)01435-8/pdf/Oestrogens+and+Prostat... - 0 views

www.europeanurology.com/...el+Concepts+about+an+Old+Issue

prostate cancer estrogen 3-beta androstanediol DHT androgens Testosterone male men hormone hormones

shared by Nathan Goodyear on 20 Jan 14 - No Cached
  • Nathan Goodyear on 20 Jan 14
     
    Nice review of the proposed complex interaction between hormones and prostate cancer.  The complex nature of the development of cancer will likely eliminate the complete elucidation of the mechanism of prostate cancer.  However, there are many pieces that would favor: increased aromatase activity appears to play a significant role int he development of prostate cancer, clearly intraprostatic hormones are different than serum making serum evaluation of sex hormones irrelevant--the move should be to salivary hormones, and the growing knowledge of DHT metabolites in the protection of prostate cancer--3 beta androstanediol.
Nathan Goodyear

Intratumoral androgen biosynthesis in prostate cancer pathogenesis and response to therapy - 0 views

erc.endocrinology-journals.org/...R175.full

prostate cancer DHT 3-beta-diol 3-alpha-diol metabolites metabolite male men hormone hormones androgen deprivation therapy

shared by Nathan Goodyear on 03 Feb 14 - No Cached
  • Additional studies have similarly found that prostate tissue levels of DHT in PCa patients treated with ADT therapy before prostatectomy declined by only ∼75% versus declines of ∼95% in serum levels
  • In a recent study in healthy men, treatment for 1 month with a GnRH antagonist to suppress testicular androgen synthesis caused a 94% decline in serum testosterone, but only a 70–80% decline in prostate tissue testosterone and DHT
  • progression to CRPC was associated with increased intratumoral accumulation or synthesis of testosterone.
  • ...9 more annotations...
  • the intraprostatic synthesis of testosterone from adrenal-derived precursors likely accounts for the relatively high testosterone levels in prostate after ADT
  • In addition, AR activity in these cells is likely further enhanced by multiple mechanisms that sensitize AR to low levels of androgens
  • higher affinity ligand DHT (approximately eightfold higher affinity
  • type 2 5α-reductase (SRD5A2) being the major enzyme in prostate
  • reduce DHT to 5α-androstane-3α,17β-diol (3α-androstanediol; Ji et al. 2003, Rizner et al. 2003), which is then glucuronidated to form 3α-androstanediol glucuronide by the enzymes UDP glycosyltransferase 2, B15 (UGT2B15) or UGT2B17
  • DHT in prostate is inactivated by the enzyme AKR1C2, which is also termed 3α-hydroxysteroid dehydrogenase type 3 (3α-HSD type 3
    • Nathan Goodyear
      Nathan Goodyear on 03 Feb 14
       
      The metabolite 3-alpha androstanediol is NOT inactive as this author states.  This DHT metabolite actually can stimulate  ER alpha receptors in the prostate.
  • AKR1C1, is also expressed in prostate. However, in contrast to AKR1C2, it converts DHT primarily to 5α-androstane-3β,17β-diol (3β-androstanediol; Steckelbroeck et al. 2004), which is a potential endogenous ligand for the estrogen receptor β
  • Significantly, intraprostatic testosterone levels were not substantially reduced relative to controls with normal serum androgen levels, although DHT levels were reduced to 18% of controls
  • testosterone levels in many of the CRPC samples were actually increased relative to control tissues (Montgomery et al. 2008). While DHT levels were less markedly increased, this may have reflected DHT catabolism
  • Nathan Goodyear on 03 Feb 14
     
    This article discusses the failure of androgen deprivation therapy and prostate cancer.  This failure is quite common.  The authors point to alpha-DHT as the primary mechanism through AR stimulation.  However, we know that DHT metabolites also stimulate estrogen receptors.
Nathan Goodyear

Testosterone therapy for men at ris... [Curr Treat Options Oncol. 2006] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...16904053

prostate disease cancer hormone hormones therapy Testosterone Estrogen Estradiol men male

shared by Nathan Goodyear on 25 Sep 13 - No Cached
  • Nathan Goodyear on 25 Sep 13
     
    It is important to understand that hormones in serum do not reflect the hormonal environment in the prostate.  Additionally, the diseased prostate does not respond the same as a healthy prostate.  That is high advanced Prostate cancer will respond to estrogen therapy and early prostate disease will increase with increased aromatase Testosterone to Estradiol conversion.
Nathan Goodyear

Chronic Inflammation in Benign Prostate Tissue Is Associated with High-Grade Prostate C... - 0 views

cebp.aacrjournals.org/...1055-9965.EPI-13-1126.abstract

inflammation prostate cancer prostatitis infection

shared by Nathan Goodyear on 22 Apr 14 - No Cached
  • Nathan Goodyear on 22 Apr 14
     
    Chronic prostattis in men associated with prostate cancer.  Even more concerning, is the increase in high Gleasons score prostate cancer.  This is no surprise as inflammation will increase aromatase activity in the prostate which will increase estrogen production which has been shown to be carcinogenic.
Nathan Goodyear

Diagnostic Pathology | Full text | Estrogen receptor beta expression in prostate adenoc... - 0 views

www.diagnosticpathology.org/...61

prostate cancer estrogen receptor estrogen receptor beta ER-beta hormone hormones receptor receptors estrogen

shared by Nathan Goodyear on 09 Jan 13 - No Cached
  • Nathan Goodyear on 09 Jan 13
     
    ER beta and prostate cancer.  More aggressive prostate cancer is found to be associated with lower ER beta expression in the prostate.  this makes sense, as other studies have shown that ER beta in the prostate can induce apoptosis (cell death), which is a powerful mechanism to regulate uncontrolled growth as found in cancer.
Nathan Goodyear

Frequent Loss of Estrogen Receptor-β Expression in Prostate Cancer - 0 views

cancerres.aacrjournals.org/...5331.long

ER beta prostate cancer prostate cancer estrogen receptor estrogen receptor receptors hormone hormones

shared by Nathan Goodyear on 05 Feb 13 - No Cached
  • Nathan Goodyear on 05 Feb 13
     
    Loss of ER-beta expression in the prostate associated with increased progression from a normal prostate to prostate cancer.
Nathan Goodyear

Effect of aging on endogenous level of 5 alpha-dihydrotestosterone, testosterone, estra... - 0 views

jcem.endojournals.org/...375.short

BPH testosterone DHT Estradiol Estrone E2 E1 men prostate aging

shared by Nathan Goodyear on 18 Sep 12 - No Cached
  • Nathan Goodyear on 18 Sep 12
     
    Men with BPH found to have higher levels of stromal Estradiol and Estrone.  This is associated with aging.  This elevation was not found in the prostate epithelium.  No correlation with Testosterone and the stroma and epithelium were found.  So, the point is that what is happening in the prostate appears to be related to increased aromatase activity in the prostate.  Which this has been shown to be evident in the lateral lobes of the prostate in other studies.  But DHT?  The numbers here are slightly elevated.  BUt the balance of DHT to Estradiol may be more important than the individual levels.  This study was done in humans.
Nathan Goodyear

Comparative Studies of the Estrogen Receptors β and α and the Androgen Recept... - 0 views

ajp.amjpathol.org/...fulltext

ER beta ER-beta AR androgen receptors ER alpha ER-alpha prostate disease cancer estrogen receptor hormone hormones men male

shared by Nathan Goodyear on 21 Jan 14 - No Cached
  • ER-β is predominately immunolocalized in basal cells and to a lesser extent in stromal cells of the morphologically normal human prostate
  • ER-α is detected in stromal cells and rarely in basal cells of the normal gland
  • AR was predominately localized in the nuclei of differentiated secretory cells and variably in basal cells of the normal acinar/duct unit as well as in stromal cells
  • ...9 more annotations...
  • Hall and colleagues44 have reported that ER-β functions as a transdominant inhibitor of ER-α transcription and that it acts to decrease overall cellular sensitivity to estradiol
  • The expression of ER-β was diminished in high-grade dysplasias when compared to normal glands and lower grade lesions.
  • The transition from normal to low/moderate dysplastic glands in the peripheral zone was marked by the appearance of ER-β homogeneously immunostained nuclei in secretory as well as basal cells with no changes in the localization of the other receptors.
  • proliferative signals mediated by AR in basal cells or by ER-α and AR in stromal cells may be opposed by the purported growth-inhibitory action of ER-β25, 26, 27, 28 localized in basal cells.
  • The diminution of ER-β expression in high-grade dysplasias and grade 4/5 cancers may be therefore related to the alteration of DNA methylation pattern in CpG islands of the promoter, resulting in down-regulation of the receptor at the transcriptional level
  • based on the proposed anti-proliferative function of the receptor,25, 26, 27, 28 the presence of ER-β in secretory cells of low/moderate-grade lesions may represent a transient abortive attempt to counter growth of these cells
  • the attrition of receptor-positive basal cells in the high-grade dysplasias may signify a continuing loss of growth inhibitory function mediated by ER-β in these precursor lesions
  • Our findings in prostate therefore differ from those reported for human colon cancer in which Folley and colleagues48 demonstrated that a selective loss of ER-β protein but not receptor message expression occurs in these neoplasms
  • Our findings therefore differed from those of Bonkhoff and colleagues33 who found immunostaining for the receptor in high-grade dysplasias and grade 4/5 carcinomas. Using in situ hybridization these authors also reported that a high percentage of dysplasias and carcinomas in their study contained cells that expressed ER-α message
  • Nathan Goodyear on 21 Jan 14
     
    Very nice study.  The authors looked at normal prostate, early disease and late stage prostate cancer.  The authors found that ER beta expression, as a general rule, was lost as progression occurred to the high-grade dysplasias and grad 4/5 carcinomas of the prostate.  Early low/moderate dysplasia was associated with an increase in ER beta--the authors propose that this was due to an attempt of the basal epithelium to counter the paracrine effect of ER alpha.   In contrast, androgen receptors appeared to be equally expressed across all.
Nathan Goodyear

Increased Endogenous Estrogen Synthesis Leads to the Sequential Induction of Prostatic ... - 0 views

www.journals.elsevierhealth.com/...fulltext

estrogen Testosterone inflammation aromatase men male hormone hormones prostate prostatitis prostate cancer

shared by Nathan Goodyear on 21 Aug 13 - No Cached
  • Nathan Goodyear on 21 Aug 13
     
    Estrogens, through elevated aromatase activity, in men is associated with increased inflammation and thus prostatitis and precancerous conditions of the prostate.
Nathan Goodyear

Environmental Estrogen Exposure During Fetal Life: A Time Bomb for Prostate Cancer: End... - 0 views

press.endocrine.org/...en.2014-1057

environmental toxins BPA prostate cancer xenoestrogens men male hormones pregnancy exposure

shared by Nathan Goodyear on 26 Mar 14 - No Cached
  • Nathan Goodyear on 26 Mar 14
     
    environmental toxins that have estrogenic activity, i.e. BPA alter the prostate stem cells.  These and other xenoestrogens, as they are collectively called, increase the sensitivity of the prostate to estrogen.  This increases the risk of prostate Ca.  This just sets the pattern of signal interpretation and sensitivity.  Add in the continued estrogenic environment, add in the excess weight, the increased aromatase activity and resultant estrogen production and one has all the ingredients for prostate cancer.
Nathan Goodyear

Long-term effects of finasteride on prostate specific antigen levels: results from the ... - 0 views

www.ncbi.nlm.nih.gov/...16093979

5 alpha reductase finasteride 5 alpha reductase inhibitors PSA BPH prostate disease cancer men male hormones

shared by Nathan Goodyear on 14 Oct 15 - No Cached
  • Nathan Goodyear on 14 Oct 15
     
    PSA increased more in men with prostate cancer compared to no disease in men on finasteride therapy. This supports the idea that finasteride has a greater PSA reduction in benign prostate disease compared to prostate cancer.
Nathan Goodyear

Estrogen receptor β and the progression of prostate cancer: role of 5α-andros... - 0 views

erc.endocrinology-journals.org/...731.long

3-beta androstanediol DHT Testosterone androgens prostate cancer ER beta ER-beta receptors ER men male hormone hormones

shared by Nathan Goodyear on 21 Jan 14 - No Cached
  • In the prostate, ERβ is highly expressed in the epithelial compartment, where it is the prevailing isoform
  • In the gland, DHT may be either reversibly 3α- or irreversibly 3β-hydroxylated by the different 3α- and 3β-hydroxysteroid dehydrogenases respectively (Steckelbroeck et al. 2004); these transformations generate two metabolites respectively 3α-diol and 3β-Adiol, which are both unable to bind the AR. Instead, 3β-Adiol displays a high affinity for ERβ (Kuiper et al. 1998, Nilsson et al. 2001), and it has been proposed that this metabolite may play a key role in prostate development
  • ERβ signaling, in contrast to ERα, seems to act as a suppressor of prostate growth, and may be positively involved in breast cancer
  • ...4 more annotations...
  • 3β-Adiol counteracts PC cell proliferation in vitro
  • 3β-Adiol counteracts the biological actions of its androgenic precursors testosterone and DHT
  • functional antagonism of 3β-Adiol appears to be molecularly independent from the activation of the androgenic pathway
  • the action of 3β-Adiol is mediated, at the molecular levels, by the estrogenic pathway.
  • Nathan Goodyear on 21 Jan 14
     
    another awesome article dealing with hormone metabolites. Physicians that don't understand metabolites and receptors may be doing more harm than good.   One of the mainstays of the treatment of metastatic prostate disease is androgen deprivation therapy.  This article requires a reassessment of this due to the DHT metabolite 3-beta androstanediol.  This metabolite is produced from DHT production via the enzyme 3beta HSD.  This metabolite binds to ER beta, an estrogen receptor, and inhibits proliferation, migration, promotes adhesion (limits spreading), and stimulates apoptosis.  This is contrast to 3-alpha androstanediol.  Androgen deprivation therapy will decrease 3-beta androstanediol.  This is the likely reason for the increased aggressive prostate cancer found in those men using 5 alpha reductase inhibitors.
Nathan Goodyear

Increased Endogenous Estrogen Synthesis Leads to the Sequential Induction of Prostatic ... - 0 views

www.ncbi.nlm.nih.gov/...PMC2731137

aromatase activity estrogen estradiol estrone testosterone prostate cancer prostatitis inflammation

shared by Nathan Goodyear on 26 Apr 12 - No Cached
  • Nathan Goodyear on 26 Apr 12
     
    study shows that over expression of aromatase activity and resultant increased estradiol/estrone production increases prostatitis and plays a role in prostate cancer.  
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