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Nathan Goodyear

Progesterone metabolites regulate induction, growth, and suppression of estrogen- and p... - 0 views

www.ncbi.nlm.nih.gov/...PMC3706910

progesterone metabolites metabolite 5-alpha pregnene 5-alpha pregnenes 5alpha-dihydroprogesterone 4-pregnene 4-pregnenes 3alpha-dihydroprogesterone breast cancer ER PR hormone hormones receptors estrogen

shared by Nathan Goodyear on 28 Jan 14 - No Cached
  • in vitro studies had shown that the progesterone metabolites, 5α-dihydroprogesterone (5αP) and 3α-dihydroprogesterone (3αHP), respectively, exhibit procancer and anticancer effects on receptor-negative human breast cell lines
  • Onset and growth of ER/PR-negative human breast cell tumors were significantly stimulated by 5αP and inhibited by 3αHP
  • When both hormones were applied simultaneously, the stimulatory effects of 5αP were abrogated by the inhibitory effects of 3αHP and vice versa
  • ...31 more annotations...
  • Treatment with 3αHP subsequent to 5αP-induced tumor initiation resulted in suppression of further tumorigenesis and regression of existing tumors
  • Tumorigenesis of ER/PR-negative breast cells is significantly enhanced by 5αP and suppressed by 3αHP, the outcome depending on the relative concentrations of these two hormones in the microenvironment in the breast regions
  • The findings show that the production of 5αP greatly exceeds that of 3αHP in ER/PR-negative tumors and that treatment with 3αHP can effectively block tumorigenesis and cause existing tumors to regress
  • hypothesis that a high 3αHP-to-5αP concentration ratio in the microenvironment may foster normalcy in noncancerous breast regions.
  • a large proportion (about 30% to 60%) of breast tumors are ER and/or PR negative
  • about 90% of normal proliferating breast epithelial cells are receptor negative
  • Our previous in vitro studies had shown that breast tissues and cell lines readily convert progesterone to 5α-pregnanes, such as 5αP, and delta-4-pregnenes, such as 3αHP (Figure ​(Figure1),1), and that tumorous breast tissues [15] and tumorigenic breast cell lines [16] produce higher levels of 5αP and lower levels of 3αHP than do normal breast tissues and nontumorigenic cell lines
  • The progesterone metabolism studies suggested that increases in 5αP and decreases in 3αHP production accompany the shift toward breast cell neoplasia and tumorigenicity
  • In vitro studies on five different human breast cell lines showed that cell proliferation and detachment are significantly increased by 5αP and decreased by 3αHP
  • the prevailing theory of hormonal regulation of breast cancer, as well as hormone-based therapies, revolves around estrogen and/or progesterone and ER/PR-positive breast cells and tumors.
  • Not only do these "receptor-negative" breast cancers fail to benefit from current hormonal therapies, but they also generally exhibit more-aggressive biologic behaviors and poorer prognosis than the receptor-positive ones
  • The results of the studies reported here show for the first time that the progesterone metabolites, 5αP and 3αHP, act as hormones that regulate ER/PR-negative breast tumor formation, growth, and regression
  • The onset of the ER/PR-negative human breast cell tumors in mice was considerably accelerated, and the growth significantly stimulated, by just one or two applications of 5αP
  • In contrast, 3αHP retarded onset of tumor formation, suppressed tumor growth, and inhibited or regressed existing 5αP-induced tumors
  • When both hormones were administered simultaneously, the effects of one were abrogated by the effects of the other.
  • The 5αPR and 3αHPR (which are associated with the plasma membranes of both ER/PR-positive [19] and ER/PR-negative [29] cells) are distinct from each other and from known ER, PR, androgen, and corticosteroid receptors, and lack affinity for other steroids, such as progesterone, estrogen, androgens, corticosteroids, and other progesterone metabolites
  • Levels of 5αPR are upregulated by 5αP itself and estradiol, and downregulated by 3αHP in both ER/PR-positive and -negative cells
  • ndications are that 5αP acts via the surface receptor-linked mitogen-activated protein kinase (MAPK; Erk1/2) pathway; 5αP significantly stimulates activation of Erk1/2 [30], increases the Bcl-2/Bax expression ratio [18] and actin depolymerization [31], and decreases expression of actin and adhesion plaque-associated vinculin [31], resulting in decreased apoptosis and increased mitosis and cell detachment
  • 3αHP appears to suppress protein kinase C (PKC), phospholipase C (PLC), Ca2+ mobilization (unpublished observations), and the Bcl-2/Bax expression ratio [18], and increases expression of the cell-cycle inhibitor p21 [18], resulting in increased apoptosis and decreased proliferation and detachment of breast cell lines.
  • serum from mice with tumors had significantly more 5αP than 3αHP
  • the tumors, which on average had about threefold higher concentrations of 5αP than the respective sera, and >10-fold higher 5αP than 3αHP levels
  • Previous in vitro metabolism studies showed that human breast tumor tissues convert significantly more progesterone to 5α-pregnanes like 5αP and less to 4-pregnenes like 3αHP than do paired normal (nontumorous) tissues
  • Similar differences in progesterone metabolism and enzyme gene expressions were observed between tumorigenic and nontumorigenic breast cell lines
  • breast carcinomas are able to synthesize progesterone
  • The current findings, along with the previous in vitro studies, suggest that the relative concentrations of 5αP and 3αHP in the breast microenvironment constitute important autocrine/paracrine determinants not only for tumorigenesis but also for potential regression of tumors and the maintenance of normalcy of ER/PR-negative breast cells/tissues.
  • Evidence presented here shows that a high concentration of 5αP, relative to 3αHP in the microenvironment, promotes initiation and growth of tumors, whereas a higher concentration of 3αHP, relative to 5αP, suppresses tumorigenesis and promotes normalcy
  • 5α-reductase and 5αPR levels are upregulated by 5αP
  • in the 3αHP-treated mice, the elevated 3αHP levels, relative to 5αP, in the microenvironment could have opposed progression to xenograft neoplasia by its inherent anticancer actions and the suppression of 5αP synthesis and 5αPR expression
  • the opposing actions of the progesterone metabolites also appear to exert some control over the estrogen-regulated effects on breast cancer by their ability to modulate ER numbers in ER-positive cells
  • because both ER/PR-negative and ER/PR-positive, as well as normal and tumorigenic human breast cell lines, have been shown to respond to 5αP and 3αHP in vitro, it is suggested that these endogenously produced progesterone metabolites may also play regulatory hormonal roles in ER/PR-positive breast cancers, as well as in the maintenance of normalcy in nontumorous breast tissues.
  • The in vivo data provide further evidence that progesterone metabolites, such as 5αP and 3αHP, deserve to be considered as active hormones in their own right, rather than inactive waste products
  • Nathan Goodyear on 28 Jan 14
     
    Progesterone metabolites and breast cancer
Nathan Goodyear

Thyroid Hormones (T3 and T4): Dual Effect on Human Cancer Cell Proliferation - 0 views

ar.iiarjournals.org/...89.long

triiodothyronine thyroid hormones hormone cancer

shared by Nathan Goodyear on 13 Aug 14 - No Cached
  • Nathan Goodyear on 13 Aug 14
     
    The effects of T3 on cancer cell lines varies.  All cell lines came from the same tissue. It doesn't appear that simply stating T3 promotes cellular metabolism and thus provides an increase in cancer progression risk.  Some cell lines studies actually had an inhibition of cell growth, whereas others saw an increase.  
Nathan Goodyear

The river blindness drug Ivermectin and related macrocyclic lactones inhibit WNT-TCF pa... - 0 views

www.ncbi.nlm.nih.gov/...PMC4287931

ivermectin cancer WTF Selamectin

shared by Nathan Goodyear on 19 Mar 18 - No Cached
  • WNT signaling
  • early colon cancers commonly display loss of function of the tumor suppressor Adenomatous polyposis coli (APC), a key component of the β-CATENIN destruction complex
  • Other cancers also show an active canonical WNT pathway; these include carcinomas of the lung, stomach, cervix, endometrium, and lung as well as melanomas and gliomas
  • ...31 more annotations...
  • In normal embryogenesis and homeostasis, the canonical WNT pathway is activated by secreted WNT ligands produced in highly controlled context-dependent manners and in precise amounts. WNT activity is transduced in the cytoplasm, inactivates the APC destruction complex, and results in the translocation of activate β-CATENIN to the nucleus, where it cooperates with DNA-binding TCF/LEF factors to regulate WNT-TCF targets and the ensuing genomic response
  • beyond the loss of activity of the APC destruction complex, for instance throughAPC mutation, phosphorylation of β-CATENIN at C-terminal sites is required for the full activation of WNT-TCF signaling and the ensuing WNT-TCF responses in cancer.
  • The WNT-TCF response blockade that we describe for low doses of Ivermectin suggests an action independent to the deregulation of chloride channels
  • involve the repression of the levels of C-terminally phosphorylated β-CATENIN forms and of CYCLIN D1, a critical target that is an oncogene and positive cell cycle regulator.
  • the Avermectin single-molecule derivative Selamectin, a drug widely used in veterinarian medicine (Nolan & Lok, 2012), is ten times more potent acting in the nanomolar range
  • Ivermectin also diminished the protein levels of CYCLIN D1, a direct TCF target and oncogene, in both HT29 and H358 tumor cells
  • Activated Caspase3 was used as a marker of apoptosis by immunohistochemistry 48 h after drug treatment. Selamectin and Ivermectin induced up to a sevenfold increase in the number of activated Caspase3+ cells in two primary (CC14 and CC36) and two cell line (DLD1 and Ls174T) colon cancer cell types (Fig​(Fig2C).2C). All changes were significative
  • The strong downregulation of the expression of the intestinal stem cell genesASCL2 andLGR5 (van der Flieret al, 2009; Scheperset al, 2012; Zhuet al, 2012b) by Ivermectin and Selamectin (Fig​(Fig2D)2D) raised the possibility that these drugs could affect WNT-TCF-dependent colon cancer stem cell behavior
  • Pre-established H358 tumors responded to Ivermectin showing a ˜ 50% repression of growth
  • Ivermectin hasin vivo efficacy against human colon cancer xenografts sensitive to TCF inhibition with no discernable side effects
  • Ivermectin (Campbellet al, 1983), an off-patent drug approved for human use, and related macrocyclic lactones, have WNT-TCF pathway response blocking and anti-cancer activities
  • these drugs block WNT-TCF pathway responses, likely acting at the level of β-CATENIN/TCF function, affecting β-CATENIN phosphorylation status.
  • anti-WNT-TCF activities of Ivermectin and Selamectin
  • Ivermectin has a well-known anti-parasitic activity mediated via the deregulation of chloride channels, leading to paralysis and death (Hibbs & Gouaux, 2011; Lynagh & Lynch, 2012). The same mode of action has been suggested to underlie the toxicity of Ivermectin for liquid tumor cells and the potentiation or sensitization effect of Avermectin B1 on classical chemotherapeutics
  • the specificity of the blockade of WNT-TCF responses we document, at low micromolar doses for Ivermectin and low nanomolar doses for Selamectin, indicate that the blockade of WNT-TCF responses and chloride channel deregulation are distinct modes of action
  • What is key then is to find a dose and a context where the use of Ivermectin has beneficial effects in patients, paralleling our results with xenografts in mice.
  • Cell toxicity appears at doses greater (> 10 μM for 12 h or longer or > 5 μM for 48 h or longer for Ivermectin) than those required to block TCF responses and induce apoptosis.
  • Our data point to a repression of WNT-β-CATENIN/TCF transcriptional responses by Ivermectin, Selamectin and related macrocylic lactones.
  • (i) The ability of Avermectin B1 to inhibit the activation of WNT-TCF reporter activity by N-terminal mutant (APC-insensitive) β-CATENIN as detected in our screen
  • (ii) The ability of Avermectin B1, Ivermectin, Doramectin, Moxidectin and Selamectin to parallel the modulation of WNT-TCF targets by dnTCF
  • (iii) The finding that the specific WNT-TCF response blockade by low doses of Ivermectin and Selamectin is reversed by constitutively active TCF
  • (iv) The repression of key C-terminal phospho-isoforms of β-CATENIN resulting in the repression of the TCF target and positive cell cycle regulator CYCLIN D1 by Ivermectin and Selamectin
  • (v) The specific inhibition ofin-vivo-TCF-dependent, but notin-vivo-TCF-independent cancer cells by Ivermectin in xenografts.
  • These results together with the reduction of the expression of the colon cancer stem cell markersASCL2 andLGR5 (e.g., Hirschet al, 2013; Ziskinet al, 2013) raise the possibility of an inhibitory effect of Ivermectin, Selamectin and related macrocyclic lactones on TCF-dependent cancer stem cells.
  • the capacity of cancer cells to form 3D spheroids in culture, as well as the growth of these, is also WNT-TCF-dependent (Kanwaret al, 2010) and they were also affected by Ivermectin treatment
  • If Ivermectin is specific, it should only block TCF-dependent tumor growth. Indeed, the sensitivity and insensitivity of DLD1 and CC14 xenografts to Ivermectin treatment, respectively, together with the desensitization to Ivermectin actionin vivo by constitutively active TCF provide evidence of the specificity of this drug to block an activated WNT-TCF pathway in human cancer.
  • Ivermectin has a good safety profile since onlyin-vivo-dnTCF-sensitive cancer xenografts are responsive to Ivermectin treatment, and we have not detected side effects in Ivermectin-treated mice at the doses used
  • previous work has shown that side effects from systemic treatments with clinically relevant doses in humans are rare (Yang, 2012), that birth defects were not observed after exposure of pregnant mothers (Pacquéet al, 1990) and that this drug does not cross the blood–brain barrier (Kokozet al, 1999). Similarly, only dogs with mutantABCB1 (MDR1) alleles leading to a broken blood–brain barrier show Ivermectin neurotoxicity (Mealeyet al, 2001; Orzechowskiet al, 2012)
  • Indications may include treatment for incurable β-CATENIN/TCF-dependent advanced and metastatic human tumors of the lung, colon, endometrium, and other organs.
  • Ivermectin, Selamectin, or related macrocyclic lactones could also serve as topical agents for WNT-TCF-dependent skin lesions and tumors such as basal cell carcinomas
  • they might also be useful as routine prophylactic agents, for instance against nascent TCF-dependent intestinal tumors in patients with familial polyposis and against nascent sporadic colon tumors in the general aging population
  • Nathan Goodyear on 19 Mar 18
     
    Ivermectin, a common anti-parasitic, found to inhibit WTF-TCF pathway and decrease c-terminal phosophorylaiton of Beta-CATENIN all resulting in increased aptosis and inhibition of cancer growth in colon cancer cell lines and lung cancer cell lines.
Nathan Goodyear

Intravenous Ascorbate as a Tumor Cytotoxic Chemotherapeutic Agent - 0 views

www.seanet.com/...d_hypotheses_1995-v44-p207.htm

vitamin C cancer IV vitamin C ascorbic acid

shared by Nathan Goodyear on 05 Mar 18 - No Cached
  • There is a 10 — 100-fold greater content of catalase in normal cells than in tumor cells
  • induce hydrogen peroxide generation
  • Ascorbic acid and its salts (AA) are preferentially toxic to tumor cells in vitro (6 — 13) and in vivo
  • ...36 more annotations...
  • related to intracellular hydrogen peroxide generation
  • only be obtained by intravenous administration of AA
  • Preferentially kills neoplastic cells
  • Is virtually non-toxic at any dosage
  • Does not suppress the immune system, unlike most chemotherapy agents
  • Increases animal and human resistance to infectious agents by enhancing lymphocyte blastogenesis, enhancing cellular immunity, strengthening the extracellular matrix, and enhancing bactericidal activity of neutrophils and modulation of complement protein
  • Strengthens the structural integrity of the extracellular matrix which is responsible for stromal resistance to malignant invasiveness
  • 1969, researchers at the NCI reported AA was highly toxic to Ehrlich ascites cells in vitro
  • In 1977, Bram et al reported preferential AA toxicity for several malignant melanoma cell lines, including four human-derived lines
  • Noto et al reported that AA plus vitamin K3 had growth inhibiting action against three human tumor cell lines at non-toxic levels
  • Metabolites of AA have also shown antitumor activity in vitro
  • The AA begins to reduce cell proliferation in the tumor cell line at the lowest concentration, 1.76 mg/dl, and is completely cytotoxic to the cells at 7.04 mg/dl
  • the normal cells grew at an enhanced rate at the low dosages (1.76 and 3.52 mg/dl)
  • preferential toxicity of AA for tumor cells. >95% toxicity to human endometrial adenocarcinoma and pancreatic tumor cells (ATCC AN3-CA and MIA PaCa-2) occurred at 20 and 30 mg/dl, respectively.
  • No toxicity or inhibition was demonstrated in the normal, human skin fibroblasts (ATCC CCD 25SK) even at the highest concentration of 50 mg/dl.
  • the use of very high-dose intravenous AA for the treatment of cancer was proposed as early as 1971
  • Cameron and Pauling have published extensive suggestive evidence for prolonged life in terminal cancer patients orally supplemented (with and without initial intravenous AA therapy) with 10 g/day of AA
  • AA, plasma levels during infusion were not monitored,
  • the long-term, oral dosage used in those experiments (10 g/day), while substantial and capable of producing immunostimulatory and extracellular matrix modulation effects, was not high enough to achieve plasma concentrations that are generally cytotoxic to tumor cells in culture
  • This low cytotoxic level of AA is exceedingly rare
  • 5 — 40 mg/dl of AA is required in vitro to kill 100% of tumor cells within 3 days. The 100% kill levels of 30 mg/dl for the endometrial carcinoma cells and 40 mg/dl for the pancreatic carcinoma cells in Figure 2 are typical
  • normal range (95% range) of 0.39-1.13 mg/dl
  • 1 h after beginning his first 8-h infusion of 115 g AA (Merit Pharmaceuticals, Los Angeles, CA), the plasma AA was 3.7 mg/dl and at 5 h was 19 mg/dl. During his fourth 8-h infusion, 8 days later, the 1 h plasma level was 158 mg/dl and 5 h was 185 mg/dl
  • plasma levels of over 100 mg/dl have been maintained in 3 patients for more than 5 h using continuous intravenous infusion
  • In rare instances of patients with widely disseminated and rapidly proliferating tumors, intravenous AA administration (10 — 45 g/day) precipitated widespread tumor hemorrhage and necrosis, resulting in death
  • Although the outcomes were disastrous in these cases, they are similar to the description of tumor-necrosis-factor-induced hemorrhage and necrosis in mice (52) and seem to demonstrate the ability of AA to kill tumor cells in vivo.
  • toxic effects of AA on one normal cell line were observed at 58.36 mg/dl and the lack of side effects in patients maintaining >100 mg/dl plasma levels
  • Although it is very rare, tumor necrosis, hemorrhage, and subsequent death should be the highest priority concern for the safety of intravenous AA for cancer patients.
  • Klenner, who reported no ill effects of dosages as high as 150 g intravenously over a 24-h period
  • Cathcart (55) who describes no ill effects with doses of up to 200 g/d in patients with various pathological conditions
  • following circumstances: renal insufficiency, chronic hemodialysis patients, unusual forms of iron overload, and oxalate stone formers
  • Screening for red cell glucose-6-phosphate dehydrogenase deficiency, which can give rise to hemolysis of red blood cells under oxidative stress (57), should also be performed
  • any cancer therapy should be started at a low dosage to ensure that tumor hemorrhage does not occur.
  • patient is orally supplementing between infusions
  • a scorbutic rebound effect can be avoided with oral supplementation. Because of the possibility of a rebound effect, measurement of plasma levels during the periods between infusions should be performed to ensure that no such effect takes place
  • Every effort should be made to monitor plasma AA levels when a patient discontinues intravenous AA therapy.
  • Nathan Goodyear on 05 Mar 18
     
    Older study, 1995, but shows the long-standing evidence that IVC preferentially is cytotoxic to cancer cells.`
Management Health Solutions Inc

Webinar: Focusing on the Big Picture of Your Supply Chain Yields Compelling Financial R... - 0 views

upcoming.yahoo.com/...fairfield

mhs events

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  • Management Health Solutions Inc on 24 Oct 12
     
    Continuous changes in the healthcare reimbursement criteria require executives across the industry to focus on enterprise-wide changes that have a positive effect on supply chain savings. It's a complex problem and it's easy to get distracted on one issue when having the ability to see a clear BIG picture of your entire supply chain is what can lead to the most dramatic results and return on investments. Register for MHS' webinar on November 01 (2:00pm EST) to learn about how their customers experience an average 4:1 ROI with continual savings into the millions and a positive financial impact to their bottom line through inventory reduction, avoidance of obsolete and expired inventory, improved charge capture for each patient, and physician preference card optimization. Click on http://bit.ly/UvD3nq Presenters *Michael Ferris: Co-Founder, MHS with over 30 years of supply chain management experience *Steve Basiliere: Former Director of Supply Chain Services at Saints Medical Center, Lowell, MA *Art Kozyrovicius: Finance and Procurement Systems Support at New York-Presbyterian Hospital, New York, NY WHY ATTEND? Join a unique discussion with healthcare supply chain thought leaders and understand how to drive significant and sustainable supply chain operational improvements. Get a jump on making an immediate and positive impact on your bottom line as you head into 2013. Register by clicking on http://bit.ly/UvD3nq Note: Event will be online, through WebEx Please Register at http://bit.ly/UvD3nq
silver line

Obesity Treatment India at Affordable Cost - 0 views

www.biggestclassifieds.com/index.php

leading causes of obesity the childhood endocrine system diseases disorders hormonal risks health treatment information medications surgery complications

shared by silver line on 19 Jul 12 - No Cached
  • silver line on 19 Jul 12
     
    Silver line, the top hospital in Kerala, India. Silver line provide detailed informatrion about obesity, leading causes of obesity, causes of childhood obesity, the endocrine system, endocrine disorders, obesity health risks, treatment of obesity, obesity medications and obesity complications
silver line

Treatment for Diabetic Kidney Disease - 0 views

www.silverlinehospital.in/diabetic-kidney-care.php

kidney disease of diabetes and failure damage function chronic diabetic problems fatigue symptoms cause nausea vomiting heartburn dialysis itchy skin haemodialysis peritoneal transplant.

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  • silver line on 23 Jul 12
     
    Silver Line is one of the top hospital in Kochi, Kerala, India for Diabetic Kidney Care. Silver line provide expert surgeons for kidney transplantation, dialysis and treatment for kidney failure, diabetic kidney disease, diabetic kidney problems, chronic kidney disease and diagnosis the symptoms of kidney failure like fatigue, nausea and vomiting, heartburn, itchy skin.
Nathan Goodyear

Effects of androgens on telomerase activity in normal and malignant prostate cells in v... - 0 views

onlinelibrary.wiley.com/...AC2C88175F4E55359BA67DC.f03t03

androgen deprivation therapy Prostate cancer androgen deprivation therapy Testosterone Telomerase Telomere length

shared by Nathan Goodyear on 10 Jan 14 - No Cached
  • Nathan Goodyear on 10 Jan 14
     
    Androgen deprivation therapy reduces Telomerase activity in androgen dependent prostate cancer cell lines.  Conversely, Testosterone increases Telomerase activity.  In these cell lines Telomerase activity is positively associated with prostate cancer.
Nathan Goodyear

Activity and expression of progesterone metabolizing 5α-reductase, 20α-hydrox... - 0 views

www.ncbi.nlm.nih.gov/...PMC154104

progesterone metabolites breast cancer 5alpha-reductase 5-alpha pregnene 5-alpha pregnenes 4-pregnene 4-pregnenes

shared by Nathan Goodyear on 30 Jan 14 - No Cached
  • Exposure of human breast cell lines (MCF-7, MCF-10A, and ZR-75-1) to 5α-pregnanes results in changes associated with neoplasia, including increased proliferation and decreased attachment [1], depolymerization of F-actin [2] and decreases in adhesion plaque-associated vinculin
  • Exposure to 4-pregnenes results, in general, in opposite (anti-cancer-like) effects
  • 5αR1 has been detected in various androgen-independent organs, such as the liver and brain
  • ...10 more annotations...
  • 5αR2 has been found predominantly in androgen-dependent organs, such as epididymis and prostate
  • The 5α-pregnanes:4-pregnenes ratio was about 8-fold higher in tumorous than in nontumorous breast tissue after an 8-hour incubation with [14C]progesterone
  • Studies with breast cell lines, showing that 5α-pregnanes stimulate proliferation and decrease attachment of cells
  • both tissue and breast cell line studies suggest that an elevated level of progesterone 5α-reductase activity may be an indicator of breast tumorigenesis, regardless of presence or absence of ER and/or PR
  • 5αR1 is the main isoform expressed in human breast carcinomas [29] and that 5αR2 may not be associated with risk of breast cancer
  • the differences in 5α-pregnane production between the cells is due primarily to a difference in 5αR1 expression
  • As in the case of 5α-reductase activity, the presence or absence of ER and PR do not appear to be related to 5α-reductase expression.
  • the conversion of progesterone to the cancer promoting 5α-pregnanes is significantly higher in the human tumorigenic breast cell lines
  • lthough both 5αR1 and 5αR2 are expressed by these cells, the elevated 5α-reductase activity appears to be the result of significantly greater expression of 5αR1
  • Changes in progesterone metabolizing enzyme expression (resulting in enzyme activity changes) may be responsible for promoting breast cancer progression due to increased production of tumor-promoting 5α-pregnanes and decreased production of anti-cancer 20α – and 3α-4-pregnenes
  • Nathan Goodyear on 30 Jan 14
     
    balance of enzyme production between 5alpha-reductase and 20alpha-hydroxysteroid oxidoreductase and 3alpha(beta)-hydroxysteroid oxidoreductase play role in carcinogenesis and proliferation in the balance of production of progesterone metabolites. The 5alpha pregnenes are pro carcinogenic  and the 4-pregnenes are anti carcinogenic.
Nathan Goodyear

Estrogen attenuates glutamate-induced cell death by inhibiting Ca2+ influx through L-ty... - 0 views

www.ncbi.nlm.nih.gov/...PMC2700344

estrogen estradiol apoptosis neurodegeneration glutamate glutamic acid

shared by Nathan Goodyear on 10 Mar 14 - No Cached
  • Nathan Goodyear on 10 Mar 14
     
    Estradiol inhibits glutamate mediated influx of calcium and thus cell death in cell line.  Glutamate, the principle excitatory neurotransmitter, is involved in neurodegeneration through activation of calcium channels.  This study of cell line cultures found that Estradiol inhibits this process.  I question whether this is applicable to both men and women.  Time will tell.
Nathan Goodyear

Targeting estrogen receptor subtypes (ERα and ERβ) with selective ER modulato... - 0 views

joe.endocrinology-journals.org/...325.abstract

ovarian cancer ER alpha ER beta ER-alpha ER-beta ovary estrogen receptor receptors ER

shared by Nathan Goodyear on 19 May 14 - No Cached
  • Nathan Goodyear on 19 May 14
     
    Studies in breast cancer and prostate cancer have revealed different effects by ER alpha vs ER beta.  It is no surprise that the same effects are found in ovarian cancer.  This study found ER alpha antagonists and ER beta agonists "significantly" suppressed growth in the ovarian cancer cell lines SKOV3 and OV2008.  Also, ER alpha agonist and ER beta antagonist "significantly" increased growth in the same cell lines.  These findings point to in increased proliferation with ER alpha and decreased with ER beta.  This is consistent with breast and prostate cancer also.
Nathan Goodyear

Pharmacological ascorbate induces cytotoxic... [Anticancer Drugs. 2012] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...22205155

vitamin C vitamin C cancer prostate cancer prostate IV vitamin C intravenous vitamin C IV intravenous ascorbic acid

shared by Nathan Goodyear on 26 Aug 14 - No Cached
  • Nathan Goodyear on 26 Aug 14
     
    IV vitamin C induces cell death of prostate cancer cell lines via H2O2, which is not new, but what is new is the ascorbate-insensitive cell line.
Nathan Goodyear

Effects of thyroid hormones on hu... [J Steroid Biochem Mol Biol. 2008] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...18328691

triiodothyronine T3 thyroid hormone hormones breast cancer E2 Estradiol

shared by Nathan Goodyear on 13 Aug 14 - No Cached
  • Nathan Goodyear on 13 Aug 14
     
    T3 may promote cancer cell proliferation says study.  Triiodothyronine was found to enhance the MCF-7 and T47-D breast cancer cell lines.  The conclusion of the abstract discusses a role of T3 in breast cancer development and progression.  This likely has more to do with progression than development through increased metabolism of the cell lines.
wheelchairindia9

Jazzy Select Elite - 0 views

www.wheelchairindia.com/...Jazzy-Select-Elite

Jazzy Select Elite Jazzy Power Chair Jazzy Select Jazzy Select 6 Jazzy Power Chairs Pride Jazzy Select 6 Jazzy Elite Power Chair Jazzy 6

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  • wheelchairindia9 on 02 Mar 16
     
    Jazzy Select Elite The Jazzy Select Elite delivers a potent blend of power, performance and style. In-line, front-wheel drive technology gives the Elite excellent stability and maneuverability for solid performance indoors and out. Jazzy Select Elite Features Jazzy includes shroud and controller guards to protect against daily wear and tear. Red or blue color-through shroud. Black high-back seat with removable, replaceable back and seat covers. Dual-layer powder coated frame for increased durability. Larger foot platform. 40 amp, PG GC 3 controller. Built with ease of service in mind. Jazzy Select Elite Specifications Weight Capacity: 300 lbs. Turning Radius: 24.75" Width: 22.75" Length: 34.75" Maximum Speed Up to 4 mph Ground Clearance: 1.5" Front Wheels: 3" solid anti-tips Drive Wheels: 9" solid Rear Wheels: 6" solid casters Drivetrain: Two-motor, in-line, front-wheel drive Braking System Regenerative and electro-mechanical Suspension Type Limited High-Back Seating: 20"W x 20"D (max. dimensions) High-Back Seat-to-Floor Range: 21.5" - 23.5" Specialty Seating: 20"W x 20"D (max. dimensions) Specialty Seat-to-Floor Range: 16.5" - 18.5" Synergy Seating 20"W x 20"D (max. dimensions) Synergy Seat-to-Floor Range 17.25" - 19.25" Standard Electronics: 40A, PG GC3 Battery Size: 12 volt, U-1 (2 required) Standard Battery Charger: 3A, off-board Per-Charge Range Up to 15 miles Battery Weight: 24.5 lbs. each Base Weight: 68.5 lbs. Standard Seat Weight: 43 lbs. (comfort, high-back) Standard Seat Size: 18" x 18"-20"
wheelchairindia9

Tynor Hand Resting Splint Right-Left - 0 views

www.wheelchairindia.com/...Hand-Resting-Splint-Right-Left

Tynor Hand Resting Splint Right-Left resting hand splint hand resting splint tynor hand resting splint resting hand splint right Tynor Hand Resting Splint Right-Left online Tynor Hand Resting Splint Right-Left price

shared by wheelchairindia9 on 30 Mar 16 - No Cached
  • wheelchairindia9 on 30 Mar 16
     
    Tynor Hand Resting Splint Right-Left provides great help during orthopedic conditions and also keeps the wrist in the functional position. It has an aluminum dorsal and volar splints which provide strong support and keep the wrist immobilized. It has PUF lined Matty Fabric body which is light in weight and allows to carry this hand resting splint anywhere. Its Amphi-dextrous two part design gives a perfect fit around the wrist and this hand resting splint fits to all circumference. It can compress and adjust this splint as per the need. Tynor Hand Resting Splint Right-Left Features Provides splinting support to the hand Firmly holds the hand in various orthopedic conditions Maintains the hand in the functional position Has Amphi-dextrous design Easy to use and remove Has Customizable splints Comes with aluminum dorsal and volar splints Provides Rigid and strong support Gives Perfect fit and enhances the comfort Light in weight Has PUF lined Matty Fabric body Durable and Long in length Can be used for mid forearm fractures Tynor Hand Resting Splint Right-Left Measurements Measure circumference evenly around wrist joint
Nathan Goodyear

The anti-malarial artesunate is also active against cancer - 0 views

www.spandidos-publications.com/...767

Artesunate Cancer

shared by Nathan Goodyear on 18 Oct 18 - No Cached
  • Nathan Goodyear on 18 Oct 18
     
    Artesunate induces apoptosis in esophageal cell lines.
Nathan Goodyear

Activity and expression of progesterone metabolizing 5α-reductase, 20α-hydrox... - 0 views

bmccancer.biomedcentral.com/...1471-2407-3-9

hormones progesterone progesterone metabolites cancer breast cancer 5alpha reductase 5alpha-pregnane 4-pregnene

shared by Nathan Goodyear on 07 Oct 16 - No Cached
  • Nathan Goodyear on 07 Oct 16
     
    cell culture study finds that increased 5alpha reductase activity and resultant 5alpha-pregnanes are associated with breast cancer cell lines.  This is in contrast to the 4-pregnenes.  In fact, decreased 4-pregnenes are found in the same breast cancer cell lines; this suggests decreased 20alpha-HSO and 3alpha-HSO activity.
Nathan Goodyear

PLOS ONE: N-Acetyl Cysteine May Support Dopamine Neurons in Parkinson's Disease: Prelim... - 0 views

journals.plos.org/...article

Parkinsons Parkinson's disease NAC N-acetylcysteine brain

shared by Nathan Goodyear on 17 Jun 16 - No Cached
  • Nathan Goodyear on 17 Jun 16
     
    pilot study finds that NAC protects the dopaminergic neurons in the brains in cell line stud.  Clinical found increased dopamine binding in the brain compared to placebo in individuals with Parkinson's disease.
Nathan Goodyear

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.
Nathan Goodyear

Access : Prognostic and predictive value of plasma testosterone levels in patients rece... - 0 views

www.nature.com/...bjc2014189a.html

Testosterone prostate cancer men male hormone hormones

shared by Nathan Goodyear on 14 Apr 14 - No Cached
  • Nathan Goodyear on 14 Apr 14
     
    Higher base-line Testosterone levels associated with longer overall survival in men with prostate cancer.  The comparison was 32.7 months with higher T levels versus 22.4 months with lower T levels.  Anemia was also a poor prognostic variable.  Whether exogenous Testosterone therapy will change this is still unclear, but the authors suggest that this should play a role in whether to use salvage hormone therapy.
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