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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

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

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

Substantial contribution of extrinsic risk factors to cancer development - 0 views

www.ncbi.nlm.nih.gov/...PMC4836858

cancer lifestyle

shared by Nathan Goodyear on 03 Jan 18 - No Cached
  • Here we provide evidence that intrinsic risk factors contribute only modestly (&lt;10~30%) to cancer development
  • we conclude that cancer risk is heavily influenced by extrinsic factors. These results carry immense consequences for strategizing cancer prevention
  • cancers are proposed to originate from the malignant transformation of normal tissue progenitor and stem cells
  • ...14 more annotations...
  • “Intrinsic processes” include those that result in mutations due to random errors in DNA replication whereas “extrinsic factors” are environmental factors that affect mutagenesis rates (such as UV radiation, ionizing radiation, and carcinogens
  • intrinsic factors do not play a major causal role.
  • intrinsic cancer risk should be determined by the cancer incidence for those cancers with the least risk in the entire group controlling for total stem cell divisions
  • if one or more cancers would feature a much higher cancer incidence, for example, lung cancer among smokers vs. non-smokers, then this most likely reflects additional (and probably extrinsic) risk factors (smoking in this case)
  • Particularly, for breast and prostate cancers, it has long been observed that large international geographical variations exist in their incidences (5-fold for breast cancer, 25-fold for prostate cancer)14, and immigrants moving from countries with lower cancer incidence to countries with higher cancer rates soon acquire the higher risk of their new country
  • Colorectal cancer is another high-incidence cancer that is widely considered to be an environmental disease17, with an estimated 75% or more colorectal cancer risk attributable to diet
  • melanoma, its risk ascribed to sun exposure is around 65–86%
  • non-melanoma basal and squamous skin cancers, ~90% is attributable to UV
  • 75% of esophageal cancer, or head and neck cancer are caused by tobacco and alcohol
  • HPV may cause ~90% cases in cervical cancer23, ~90% cases in anal cancer24, and ~70% in oropharyngeal cancer
  • HBV and HCV may account for ~80% cases of hepatocellular carcinoma
  • H pylori may be responsible for 65–80% of gastric cancer
  • While a few cancers have relatively large proportions of intrinsic mutations (&gt;50%), the majority of cancers have large proportions of extrinsic mutations, for example, ~100% for Myeloma, Lung and Thyroid cancers and ~80–90% for Bladder, Colorectal and Uterine cancers, indicating substantial contributions of carcinogen exposures in the development of most cancers
  • onsistent estimate of contribution of extrinsic factors of &gt;70–90% in most common cancer types. This concordance lends significant credibility to the overall conclusion on the role of extrinsic factors in cancer development
  • Nathan Goodyear on 03 Jan 18
     
    Really great read.  Cancer is a majority lifestyle disease.
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

Induction of metastasis, cancer stem cell phenotype, and oncogenic metabolism in cancer... - 0 views

www.ncbi.nlm.nih.gov/...PMC5282724

EMT TME metastasis cancer stem cells cancer MMP2 Notch MMP-9 MMP-2 radioresistance Hedgehog CSC MMP9 Snail HIF-1alpha tumor microenvironment epithelial to mesenchymal transition TGF-beta radiation

shared by Nathan Goodyear on 09 Feb 21 - No Cached
  • More than half of cancer patients are treated with IR at some point during their treatment
  • fractionation schedule is the delivery of 1.8–2.0&nbsp;Gy per day, five days per week
  • Nuclear DNA is the primary target of IR; it causes DNA damage (genotoxic stress) by direct DNA ionization
  • ...121 more annotations...
  • IR also indirectly induces DNA damage by stimulating reactive oxygen species (ROS) production
  • IR is known to induce EMT in vitro
  • p53 is activated in response to IR-induced DNA damage
  • IR paradoxically also promotes tumour recurrence and metastasis
  • DNA double-strand breaks (DSBs)
  • cancer cells undergoing EMT acquire invasive and metastatic properties
  • changes in the tumour microenvironment (TME)
  • IR seems to induce EMT and CSC phenotypes by regulating cellular metabolism
  • EMT, stemness, and oncogenic metabolism are known to be associated with resistance to radiotherapy and chemotherapy
  • Hanahan and Weinberg proposed ten hallmarks of cancer that alter cell physiology to enhance malignant growth: 1) sustained proliferation, 2) evasion of growth suppression, 3) cell death resistance, 4) replicative immortality, 5) evasion of immune destruction, 6) tumour-promoting inflammation, 7) activation of invasion and metastasis, 8) induction of angiogenesis, 9) genome instability, and 10) alteration of metabolism
  • EMT is a developmental process that plays critical roles in embryogenesis, wound healing, and organ fibrosis
  • IR is known to induce stemness and metabolic alterations in cancer cells
  • transforming growth factor-β [TGF-β], epidermal growth factor [EGF]) and their associated signalling proteins (Wnt, Notch, Hedgehog, nuclear-factor kappa B [NF-κB], extracellular signal-regulated kinase [ERK], and phosphatidylinositol 3-kinase [PI3K]/Akt
  • activate EMT-inducing transcription factors, including Snail/Slug, ZEB1/δEF1, ZEB2/SIP1, Twist1/2, and E12/E47
  • Loss of E-cadherin is considered a hallmark of EMT
  • IR has been shown to induce EMT to enhance the motility and invasiveness of several cancer cells, including those of breast, lung, and liver cancer, and glioma cells
  • IR may increase metastasis in both the primary tumour site and in normal tissues under some circumstance
  • sublethal doses of IR have been shown to enhance the migratory and invasive behaviours of glioma cells
  • ROS are known to play an important role in IR-induced EMT
  • High levels of ROS trigger cell death by causing irreversible damage to cellular components such as proteins, nucleic acids, and lipids, whereas low levels of ROS have been shown to promote tumour progression—including tumour growth, invasion, and metastasis
  • hypoxia-inducible factor-1 (HIF-1) is involved in IR-induced EMT
  • Treatment with the N-acetylcysteine (NAC), a general ROS scavenger, prevents IR-induced EMT, adhesive affinity, and invasion of breast cancer cells
    • Nathan Goodyear
      Nathan Goodyear on 09 Feb 21
       
      NAC for all patients receiving radiation therapy
  • Snail has been shown to play a crucial role in IR-induced EMT, migration, and invasion
  • IR activates the p38 MAPK pathway, which contributes to the induction of Snail expression to promote EMT and invasion
  • NF-κB signalling that promotes cell migration
  • ROS promote EMT to allow cancer cells to avoid hostile environments
  • HIF-1 is a heterodimer composed of an oxygen-sensitive α subunit and a constitutively expressed β subunit.
  • Under normoxia, HIF-1α is rapidly degraded, whereas hypoxia induces stabilisation and accumulation of HIF-1α
  • levels of HIF-1α mRNA are enhanced by activation of the PI3K/Akt/mammalian target of rapamycin (mTOR)
  • IR is known to increase stabilisation and nuclear accumulation of HIF-1α, since hypoxia is a major condition for HIF-1 activation
  • IR induces vascular damage that causes hypoxia
  • ROS is implicated in IR-induced HIF-1 activation
  • IR causes the reoxygenation of hypoxic cancer cells to increase ROS production, which leads to the stabilisation and nuclear accumulation of HIF-1
  • IR increases glucose availability under reoxygenated conditions that promote HIF-1α translation by activating the Akt/mTOR pathway
  • The stabilised HIF-1α then translocates to the nucleus, dimerizes with HIF-1β, and increases gene expression— including the expression of essential EMT regulators such as Snail—to induce EMT, migration, and invasion
  • TGF-β signalling has been shown to play a crucial role in IR-induced EMT
  • AP-1 transcription factor is involved in IR-induced TGF-β1 expression
  • Wnt/β-catenin signalling is also implicated in IR-induced EMT
  • Notch signalling is known to be involved in IR-induced EMT
  • IR also increases Notch-1 expression [99]. Notch-1 is known to induce EMT by upregulating Snail
  • PAI-1 signalling is also implicated in IR-induced Akt activation that increases Snail levels to induce EMT
  • EGFR activation is known to be associated with IR-induced EMT, cell migration, and invasion by activating two downstream pathways: PI3K/Akt and Raf/MEK/ERK
  • ROS and RNS are also implicated in IR-induced EGFR activation
  • IR has also been shown to activate Hedgehog (Hh) signalling to induce EMT
  • IR has been shown to induce Akt activation through several signalling pathways (EGFR, C-X-C chemokine receptor type 4 [CXCR4]/C-X-C motif chemokine 12 [CXCL12], plasminogen activator inhibitor 1 [PAI-1]) and upstream regulators (Bmi1, PTEN) that promote EMT and invasion
  • CSCs possess a capacity for self-renewal, and they can persistently proliferate to initiate tumours upon serial transplantation, thus enabling them to maintain the whole tumour
  • Conventional cancer treatments kill most cancer cells, but CSCs survive due to their resistance to therapy, eventually leading to tumour relapse and metastasis
  • identification of CSCs, three types of markers are utilised: cell surface molecules, transcription factors, and signalling pathway molecules
  • CSCs express distinct and specific surface markers; commonly used ones are CD24, CD34, CD38, CD44, CD90, CD133, and ALDH
  • Transcription factors, including Oct4, Sox2, Nanog, c-Myc, and Klf4,
  • signalling pathways, including those of TGF-β, Wnt, Hedgehog, Notch, platelet-derived growth factor receptor (PDGFR), and JAK/STAT
  • microRNAs (miRNAs), including let-7, miR-22, miR-34a, miR-128, the miR-200 family, and miR-451
  • Non-CSCs can be reprogrammed to become CSCs by epigenetic and genetic changes
  • EMT-inducing transcription factors, such as Snail, ZEB1, and Twist1, are known to confer CSC properties
  • Signalling pathways involved in EMT, including those of TGF-β, Wnt, and Notch, have been shown to play important roles in inducing the CSC phenotype
  • TGF-β1 not only increases EMT markers (Slug, Twist1, β-catenin, N-cadherin), but also upregulates CSC markers (Oct4, Sox2, Nanog, Klf4) in breast and lung cancer cells
  • some CSC subpopulations arise independently of EMT
  • IR has been shown to induce the CSC phenotype in many cancers, including breast, lung, and prostate cancers, as well as melanoma
  • Genotoxic stress due to IR or chemotherapy promotes a CSC-like phenotype by increasing ROS production
  • IR has been shown to induce reprogramming of differentiated cancer cells into CSCs
  • In prostate cancer patients, radiotherapy increases the CD44+ cell population that exhibit CSC properties
  • IR also induces the re-expression of stem cell regulators, such as Sox2, Oct4, Nanog, and Klf4, to promote stemness in cancer cells
  • EMT-inducing transcription factors and signalling pathways, including Snail, STAT3, Notch signalling, the PI3K/Akt pathway, and the MAPK cascade, have been shown to play important roles in IR-induced CSC properties
  • STAT3 directly binds to the Snail promoter and increases Snail transcription, which induces the EMT and CSC phenotypes, in cisplatin-selected resistant cells
  • Other oncogenic metabolic pathways, including glutamine metabolism, the pentose phosphate pathway (PPP), and synthesis of fatty acids and cholesterol, are also enhanced in many cancers
  • metabolic reprogramming
  • HIF-1α, p53, and c-Myc, are known to contribute to oncogenic metabolism
  • metabolic reprogramming
  • tumour cells exhibit high mitochondrial metabolism as well as aerobic glycolysis
  • occurring within the same tumour
  • CSCs can be highly glycolytic-dependent or oxidative phosphorylation (OXPHOS)-dependen
  • mitochondrial function is crucial for maintaining CSC functionality
  • cancer cells depend on mitochondrial metabolism and increase mitochondrial production of ROS that cause pseudo-hypoxia
  • HIF-1 then enhances glycolysis
  • CAFs have defective mitochondria that lead to the cells exhibiting the Warburg effect; the cells take up glucose, and then secrete lactate to 'feed' adjacent cancer cells
  • lactate transporter, monocarboxylate transporter (MCT)
  • nutrient microenvironment
  • Epithelial cancer cells express MCT1, while CAFs express MCT4. MCT4-positive, hypoxic CAFs secrete lactate by aerobic glycolysis, and MCT1-expressing epithelial cancer cells then uptake and use that lactate as a substrate for the tricarboxylic acid (TCA) cycle
  • MCT4-positive cancer cells depend on glycolysis and then efflux lactate, while MCT1-positive cells uptake lactate and rely on OXPHOS
  • metabolic heterogeneity induces a lactate shuttle between hypoxic/glycolytic cells and oxidative/aerobic tumour cells
  • bulk tumour cells exhibit a glycolytic phenotype, with increased conversion of glucose to lactate (and enhanced lactate efflux through MCT4), CSC subsets depend on oxidative phosphorylation; most of the glucose entering the cells is converted to pyruvate to fuel the TCA cycle and the electron transport chain (ETC), thereby increasing mitochondrial ROS production
  • the major fraction of glucose is directed into the pentose phosphate pathway, to produce redox power through the generation of NADPH and ROS scavengers
  • HIF-1α, p53, and c-Myc, are known to contribute to oncogenic metabolism
  • regulatory molecules involved in EMT and CSCs, including Snail, Dlx-2, HIF-1, STAT3, TGF-β, Wnt, and Akt, are implicated in the metabolic reprogramming of cancer cells
  • HIF-1 induces the expression of glycolytic enzymes, including the glucose transporter GLUT, hexokinase, lactate dehydrogenase (LDH), and MCT, resulting in the glycolytic switch
  • HIF-1 represses the expression of pyruvate dehydrogenase kinase (PDK), which inhibits pyruvate dehydrogenase (PDH), thereby inhibiting mitochondrial activity
  • STAT3 has been implicated in EMT-induced metabolic changes as well
  • TGF-β and Wnt play important roles in the metabolic alteration of cancer cells
  • Akt is also implicated in the glycolytic switch and in promoting cancer cell invasiveness
  • EMT, invasion, metastasis, and stemness
  • pyruvate kinase M2 (PKM2), LDH, and pyruvate carboxylase (PC), are implicated in the induction of the EMT and CSC phenotypes
  • decreased activity of PKM2 is known to promote an overall shift in metabolism to aerobic glycolysis
  • LDH catalyses the bidirectional conversion of lactate to pyruvate
  • High levels of LDHA are positively correlated with the expression of EMT and CSC markers
  • IR has been shown to induce metabolic changes in cancer cells
  • IR enhances glycolysis by upregulating GAPDH (a glycolysis enzyme), and it increases lactate production by activating LDHA, which converts pyruvate to lactate
  • IR enhances glycolysis by upregulating GAPDH (a glycolysis enzyme), and it increases lactate production by activating LDHA, which converts pyruvate to lactate
  • IR also elevates MCT1 expression that exports lactate into the extracellular environment, leading to acidification of the tumour microenvironment
  • IR increases intracellular glucose, glucose 6-phosphate, fructose, and products of pyruvate (lactate and alanine), suggesting a role for IR in the upregulation of cytosolic aerobic glycolysis
  • Lactate can activate latent TGF-
  • lactate stimulates cell migration and enhances secretion of hyaluronan from CAF that promote tumour metastasis
  • promote tumour survival, growth, invasion, and metastasis; enhance the stiffness of the ECM; contribute to angiogenesis; and induce inflammation by releasing several growth factors and cytokines (TGF-β, VEGF, hepatocyte growth factor [HGF], PDGF, and stromal cell-derived factor 1 [SDF1]), as well as MMP
  • tumours recruit the host tissue’s blood vessel network to perform four mechanisms: angiogenesis (formation of new vessels), vasculogenesis (de novo formation of blood vessels from endothelial precursor cells), co-option, and modification of existing vessels within tissues.
  • immunosuppressive cells such as tumour-associated macrophages (TAM), MDSCs, and regulatory T cells, and the immunosuppressive cytokines, TGF-β and interleukin-10 (IL-10)
  • immunosuppressive cells such as tumour-associated macrophages (TAM), MDSCs, and regulatory T cells, and the immunosuppressive cytokines, TGF-β and interleukin-10 (IL-10)
  • intrinsic immunogenicity or induce tolerance
  • cancer immunoediting’
  • three phases: 1) elimination, 2) equilibrium, and 3) escape.
  • The third phase, tumour escape, is mediated by antigen loss, immunosuppressive cells (TAM, MDSCs, and regulatory T cells), and immunosuppressive cytokines (TGF-β and IL-10).
  • IR can elicit various changes in the TME, such as CAF activity-mediated ECM remodelling and fibrosis, cycling hypoxia, and an inflammatory response
  • IR activates CAFs to promote the release of growth factors and ECM modulators, including TGF-β and MMP
  • TGF-β directly influences tumour cells and CAFs, promotes tumour immune escape, and activates HIF-1 signalling
    • Nathan Goodyear
      Nathan Goodyear on 09 Feb 21
       
      And now the receipts
  • MMPs degrade ECM that facilitates angiogenesis, tumour cell invasion, and metastasis
    • Nathan Goodyear
      Nathan Goodyear on 09 Feb 21
       
      Receipts and mechanisms
  • IR also promotes MMP-2/9 activation in cancer cells to promote EMT, invasion, and metastasis
  • IR-induced Snail increases MMP-2 expression to promote EMT
  • Radiotherapy has the paradoxical side-effect of increasing tumour aggressiveness
  • IR promotes ROS production in cancer cells, which may induce the activation of oncogenes and the inactivation of tumour suppressors, which further promote oncogenic metabolism
  • Metabolic alterations
  • oncogenic metabolism
  • elicit various changes in the TME
  • Although IR activates an antitumour immune response, this signalling is frequently suppressed by tumour escape mechanisms
  • Nathan Goodyear on 09 Feb 21
     
    Important review article.
Nathan Goodyear

The mineral selenium proves itself as powerful anti-cancer medicine - 0 views

www.naturalnews.com/016446.html

selenium cancer

shared by Nathan Goodyear on 12 May 11 - Cached
  • In a December 1996 article in the Journal of the American Medical Association, Dr. Larry Clark presented evidence that supplemental selenium could reduce cancer death rates by as much as 50%
  • patients receiving selenium had a 67% decrease in cancer of the prostate, a 58 percent decrease in colon or rectal cancer and a 45% decrease in lung cancer
  • An article in the Journal of the American Medical Association (JAMA) by Clark et al. (1996) showed that 200 mcg of supplemental selenium a day reduced overall cancer mortality by 50% in humans compared to a placebo group not receiving supplemental selenium
  • ...10 more annotations...
  • In a recent five-year study of nearly 30,000 rural Chinese people, researchers from the NCI found that daily doses of these three nutrients reduced cancer deaths by 13%.
  • In a study in Cancer Letters (Evangelou et al. 1997), animals with malignant tumors given high doses of vitamins C and E and selenium manifested a significant prolongation of the mean survival time. Complete remission of tumors developed in 16.8% of the animals
  • cities and states with high selenium content in the soil also had significantly lower rates of cancer, especially of the digestive and urinary systems.
  • In one study of hundreds of men, a daily intake of 200 micrograms of selenium cut the incidence of prostate cancer by 60 percent.
  • The statistics for breast cancer are particularly striking. "The higher the selenium, the lower the breast cancer
  • In Yugoslavia, scientists studied 33 patients with breast cancer. These women had selenium levels in their bloodstream only half those of healthy volunteers.
  • The overall reduction in cancer incidence was 37% in the selenium-supplemented group; a 50% reduction in cancer mortality was observed over a 10-year period
  • The following are the site-specific reductions in cancer incidence observed in the study: colon-rectal cancers (58%), lung cancer (46%), and prostate cancer (63%)
  • A selenium deficiency appears to increase the risk of prostate cancer fourfold to fivefold
  • It was determined that, as the male population ages, selenium levels decrease, paralleling an increase in prostate cancer
  • Nathan Goodyear on 12 May 11
     
    exhaustive discussion selenium deficiency and increased cancer risk
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

BMC Cancer | Full text | A lactate shuttle system between tumour and stromal cells is a... - 0 views

www.biomedcentral.com/...352

cancer prostate cancer CAFs cancer associated fibroblasts mono-carboxylate transporters

shared by Nathan Goodyear on 12 Nov 14 - No Cached
  • Under hypoxic conditions, tumour cells primarily use glycolysis for energy, producing lactate, which is expelled to the tumour microenvironment, allowing tumours to continue their glycolytic activity
  • Sonveaux et al. showed that lactate, which is generally considered a waste product, is preferred over glucose by oxidative tumour cells as their primary energy source
  • MCT4 is a low-affinity transporter, which is abundant in highly glycolytic muscle cells and is one of the many target genes of hypoxia-inducible factor 1 alpha (HIF-1α)
  • ...8 more annotations...
  • Other targets of HIF-1α include glucose transporter-1 (GLUT-1), the main transporter involved in glucose uptake [9,10]; lactate dehydrogenase V (LDHV), which is responsible for the conversion of pyruvate into lactate; pyruvate dehydrogenase kinase isozyme 1 (PDK1), which is responsible for the phosphorylation and consequent inactivation of pyruvate dehydrogenase (PDH); and carbonic anhydrase IX (CAIX), a hypoxia-related protein involved in pH regulation [11]. Alpha-methylacyl-CoA racemase (AMACR), pristanoyl-CoA oxidase (ACOX-3) and D-bifunctional protein (DBP), are also important fatty acid oxidation-related proteins in prostate cancer
  • the essential role played by the cross-talk between stroma and epithelium in carcinogenesis and prostate cancer progression has been increasingly recognised
  • strong membranous expression of MCT1 was consistently observed in cancer cells, suggesting a role for MCT1 in the transport of lactate into tumour cells from the acidic extracellular matrix, suggesting that lactate might be used as a fuel by oxidative cancer cells.
  • Our hypothesis is in agreement with those of Fiaschi et al.[17], who describe the metabolic reprogramming of CAFs towards the Warburg phenotype as a result of contact with prostate cancer cells
  • Using in vitro studies, they showed lactate production and efflux by de novo expressed MCT4 in CAFs and also demonstrated that, upon contact with CAFs, prostate cancer cells were reprogrammed towards aerobic metabolism, with an increase in lactate uptake via the lactate transporter MCT1.
  • pharmacological inhibition of MCT1-mediated lactate uptake dramatically affected PCa cell survival and tumour outgrowth
  • In this model, “energy transfer” or “metabolic coupling” between the tumour stroma and epithelial cancer cells fuels tumour growth and metastasis via oxidative mitochondrial metabolism in anabolic cancer cells
  • the concomitant expression of MCT1 in tumour cells and MCT4 in fibroblasts in the same tissue is clinically significant, and associated with poor prognosis.
  • Nathan Goodyear on 12 Nov 14
     
    Study confirms the importance of the crosstalk between cancer cells and CAFs via MCTs in prostate cancer.
Nathan Goodyear

Clinical experience with intravenous administration of ascorbic acid: achievable levels... - 0 views

www.ncbi.nlm.nih.gov/...PMC3751545

IV vitamin C dosing ascorbic acid inflammation disease cancer IV vitamin C intravenous vitamin C IV intravenous vitamin C vitamin C CRP therapy treatment alternative

shared by Nathan Goodyear on 26 Aug 14 - No Cached
  • Patients with higher tumor markers are likely to have higher tumor burden, higher oxidative stress and, therefore, are more likely to have lower post IVC plasma levels.
  • Our data also showed that cancer patients with metastasis tend to have lower post-IVC vitamin C levels than those without metastasis
  • Lower peak plasma concentrations are obtained in cancer patients than in healthy subjects. Cancer patients who are deficient in vitamin C prior to therapy tend to achieve lower plasma levels post infusion.
  • ...25 more annotations...
  • Patients with higher inflammation or tumor burdens, as measured by CRP levels or tumor antigen levels, tend to show lower peak plasma ascorbate levels after IVC.
  • Patients with metastatic tumors tend to achieve lower post infusion plasma ascorbate levels than those with localized tumors.
  • Meta-analyses of clinical studies involving cancer and vitamins also conclude that antioxidant supplementation does not interfere with the efficacy of chemotherapeutic regiments
  • Most of the prostate cancer patients studied, 75±19% (95% confidence), showed reductions in PSA levels during the course of their IVC therapy
  • Laboratory studies suggest that, at high concentrations, ascorbate does not interfere with chemotherapy or irradiation and may enhance efficacy in some situations
  • Cameron and Pauling observed fourfold survival times in terminal cancer patients treated with intravenous ascorbate infusions followed by oral supplementation
  • The inflammatory microenvironment of cancer cells leads to increasing oxidative stress, which apparently depletes vitamin C, resulting in lower plasma ascorbate concentrations in blood samples post IVC infusion. Another explanation for this finding may be that cancers are themselves more metabolically active in their uptake of vitamin C, causing subjects to absorb more of the vitamin, and as a results show lower plasma ascorbate concentrations in blood post IVC infusion.
  • patients with severely elevated CRP levels attain plasma ascorbate concentrations after IVC infusions that are only 65% of those attained for subjects with normal CRP levels
  • The finding of decreased plasma ascorbate levels in cancer patients may relate to the molecular structure of ascorbic acid; in particular, the similarity of its oxidized form, dihydroascorbic acid, to glucose
  • Since tumor have increased requirement for glucose [67], transport of dehydroascorbate into the cancer cells via glucose transport molecules and ascorbate through sodium-dependent transporter may be elevated
  • Increased accumulation of ascorbic acid in the tumor site was supported by measurements of the level of ascorbic acid in tumors in animal experiments
  • patients with advanced malignancies may have lower level of ascorbic acid in tissue, creating a higher demand for the vitamin C
  • IVC therapy appears to reduce CRP levels in cancer patients.
  • CRP concentrations directly correlate with disease activity in many cases and can contribute to disease progression through a range of pro-inflammatory properties.
  • Being an exquisitely sensitive marker of systemic inflammation and tissue damage, CRP is very useful in screening for organic disease and monitoring treatment responses
  • ncreases in CRP concentrations have been associated with poorer prognosis of survival in cancer patients, particularly with advance disease independent of tumor stage
  • Regarding inflammation, 73±13% of subjects (95% confidence) showed a reduction in CRP levels during therapy. This was an even more dramatic 86±13% (95% confidence) in subjects who started therapy with CRP levels above 10&nbsp;mg/L
  • patients treated by IVC with follow-up several year showed that suppression of inflammation in cancer patients by high-dose IVC is feasible and potentially beneficial
  • Inflammation is a marker of high cancer risk, and poor treatment outcome
  • The subjects with highly elevated CRP concentrations have a three-fold elevation “all-cause” mortality risk and a twenty-eight fold increase in cancer mortality risk
  • cancer patients may need higher doses to achieve a given plasma concentration.
  • patients with lower vitamin C levels may see more distribution of intravenously administered ascorbate into tissues and thus attain less in plasma.
  • When treating patients with IVC, the first treatment likely serves to replenish depleted tissue stores, if those subjects were vitamin C deficient at the beginning of the treatment. Then, in subsequent treatments, with increasing doses, higher plasma concentrations can be attained. On-going treatments serve to progressively reduce oxidative stress in cancer patients.
  • large doses given intravenously may result in maximum plasma concentrations of roughly 30&nbsp;mM, a level that has been shown to be sufficient for preferential cytotoxicity against cancer cells
  • oral intake of vitamin C exceeded 200&nbsp;mg administered once daily, it was difficult to increase plasma and tissue concentrations above roughly 200&nbsp;μM.
  • Nathan Goodyear on 26 Aug 14
     
    Great review on the use of IV vitamin C in cancer and to reduce inflammation.  The article does a great job of discussing the mechanism of vitamin C therapy in cancer as well as the proposed reasons for low vitamin C in cancer patients.  The study also highlights the obstacles to rise in vitamin C levels post IV vitamin C in cancer patients.
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

Promising role for Gc-MAF in cancer immunotherapy: from bench to bedside - 0 views

www.ncbi.nlm.nih.gov/...PMC5686300

nagalase Gc-MAF cancer

shared by Nathan Goodyear on 29 Jan 18 - No Cached
  • MAF precursor activity has also been lost or reduced after Gc-globulin treatment in some cancer cell lines
  • This appears to result from the deglycosylated ɑ-N-acetylgalactosaminidase (nagalase) secreted from cancerous cells
  • Nagalase has been detected in many cancer patients, but not in healthy individuals
  • ...31 more annotations...
  • Studies have shown that the production of nagalase has a mutual relationship with Gc-MAF level and immunosuppression
  • It has been demonstrated that serum levels of nagalase are good prognosticators of some types of cancer
  • The nagalase level in serum correlates with tumor burden and it has been shown that Gc-MAF therapy progresses, nagalase activity decreases
  • It has been shown that Gc-MAF can inhibit the angiogenesis induced by pro-inflammatory prostaglandin E1
  • The effect of Gc-MAF on chemotaxis or activation of tumoricidal macrophages is likely the main mechanism against angiogenesis.
  • Administration of Gc-MAF stimulates immune-cell progenitors for extensive mitogenesis, activates macrophages and produces antibodies. “This indicates that Gc-MAF is a powerful adjuvant for immunization.”
  • Cancer cell lines do not develop into tumor genes in mouse models after Gc-MAF-primed immunization (29-31) and the effect of Gc-MAF has been approved for macrophage stimulation for angiogenesis, proliferation, migration and metastatic inhibition on tumors induced by MCF-7 human breast cancer cell line
  • The protocol included: "a high dose of second-generation Gc-MAF (0.5 ml) administered twice a week intramuscularly for a total of 21 injections.”
  • Yamamoto et al. showed that the administration of Gc-MAF to 16 patients with prostate cancer led to improvements in all patients without recurrence
  • Inui et al. reported that a 74-year-old man diagnosed with prostate cancer with multiple bone metastases was in complete remission nine months after initiation of GcMAF therapy simultaneously with hyper T/NK cell, high-dose vitamin C and alpha lipoic acid therapy
  • It has also been approved for non-neoplastic diseases such as autism (41), multiple sclerosis (42, 43), chronic fatigue syndrome (CFS) (40), juvenile osteoporosis (44) and systemic lupus erythematous (45).
  • Gc-MAF has been verified for use in colon, thyroid (38), lung (39), liver, thymus (36), pancreatic (40), bladder and ovarian cancer and tongue squamous carcinoma
  • Prostate, breast, colon, liver, stomach, lung (including mesothelioma), kidney, bladder, uterus, ovarian, head/neck and brain cancers, fibrosarcomas and melanomas are the types of cancer tested thus far
  • weekly administration of 100 ng Gc-MAF to cancer at different stages and types showed curative effects at different follow-up times
  • this treatment has been suggested for non-anemic patients
  • Studies have shown that weekly administration of 100 ng Gc-MAF to cancer patients had curative effects on a variety of cancers
  • Because the half-life of the activated macrophages is approximately one week, it must be administered weekly
  • In vivo weekly intramuscular administration of Gc-MAF (100 ng) for 16-22 weeks was used to treat patients with breast cancer
  • individuals harboring different VDR genotypes had different responses to Gc-MAF and that some genotypes were more responsive than others
  • Administration of Gc-MAF for cancer patients exclusively activates macrophages as an important cell in adaptive immunity
  • Gc-MAF supports humoral immunity by producing, developing and releasing large quantities of antibodies against cancer. Clinical evidence from a human model of breast cancer patients supports this hypothesis
  • There is also evidence that confirms the tumoricidal role of Gc-MAF via Fc-receptor mediation
  • It is likely that the best therapeutic responses will be observed when the nutritional and inflammatory aspects are taken together with stimulation of the immune system
  • it should be noted that no harmful side effects of Gc-MAF treatment have been reported, even when it was successfully administered to autistic children
  • The natural activation mechanism of macrophages by Gc-MAF is so natural and it should not have any side effects on humans or animal models even in cell culture
  • Besides the Gc-MAF efficacy on macrophage activity, it can be a potential anti-angiogenic agent (28) and an inhibitor of the migration of cancerous cells in the absence of macrophages (47).
  • Activating or modifying natural killer cells, dendritic cells, DC, CTL, INF and IL-2 have all been recommended for cancer immunotherapy
  • It has been reported that nagalase cannot deglycosylate Gc-MAF as it has specificity for Gc globulin alone
  • inflammation-derived macrophage activation with the participation of B and T lymphocytes is the main mechanism
  • macrophages highly-activated by the addition of Gc-MAF can show tumoricidal activity
  • Previous clinical investigations have confirmed the efficacy of Gc-MAF. In addition to activating existing macrophages, Gc-MAF is a potent mitogenic factor that can stimulate the myeloid progenitor cells to increase systemic macrophage cell counts by 40-fold in four days
  • Nathan Goodyear on 29 Jan 18
     
    great review on Gc-MAF in cancer.  An increase in nagalase blocks Gc-protein to Gc-MAF activity leaving the host immune system compromised.
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

Intermediate and Longer-Term Outcomes From a Prospective Active-Surveillance Program fo... - 0 views

jco.ascopubs.org/...JCO.2015.62.5764.full

prostate cancer prostate cancer men

shared by Nathan Goodyear on 02 Sep 15 - No Cached
  • Nathan Goodyear on 02 Sep 15
     
    low aggressive prostate cancer followed conservatively results in low mortality rate in study.  The study is significant in that it followed 1,298 men up to 18 years and found reclassification to "lethal" grade prostate cancer to be only 5.9%.  This challenges long held dogma that the first approach to cancer is to cut it out. For those with low aggressive prostate cancer, conservative approaches i.e. observation, can be employed.
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

Ivermectin: enigmatic multifaceted 'wonder' drug continues to surprise and exceed expec... - 0 views

www.nature.com/ja201711

Ivermectin cancer

shared by Nathan Goodyear on 19 Mar 18 - No Cached
  • The avermectins are known to possess pronounced antitumor activity
  • Over the past few years, there have been steadily increasing reports that ivermectin may have varying uses as an anti-cancer agent, as it has been shown to exhibit both anti-cancer and anti-cancer stem cell properties
  • In human ovarian cancer and NF2 tumor cell lines, high-dose ivermectin inactivates protein kinase PAK1 and blocks PAK1-dependent growth
  • ...13 more annotations...
  • PAK1 is essential for the growth of more than 70% of all human cancers, including breast, prostate, pancreatic, colon, gastric, lung, cervical and thyroid cancers, as well as hepatoma, glioma, melanoma, multiple myeloma and for neurofibromatosis tumors
  • Ivermectin suppresses breast cancer by activating cytostatic autophagy, disrupting cellular signaling in the process, probably by reducing PAK1 expression
  • Cancer stem cells are a key factor in cancer cells developing resistance to chemotherapies and these results indicate that a combination of chemotherapy agents plus ivermectin could potentially target and kill cancer stem cells, a paramount goal in overcoming cancer
  • Triple-negative breast cancers, which lack estrogen, progesterone and HER2 receptors, account for 10–20% of breast cancers and are associated with poor prognosis
  • Ivermectin addition led to transcriptional modulation of genes associated with epithelial–mesenchymal transition and maintenance of a cancer stem cell phenotype in triple-negative breast cancers cells, resulting in impairment of clonogenic self-renewal in vitro and inhibition of tumor growth and metastasis in vivo
  • Ivermectin-induced cytostatic autophagy also leads to suppression of tumor growth in breast cancer xenografts, causing researchers to believe there is scope for using ivermectin to inhibit breast cancer cell proliferation and that the drug is a potential treatment for breast cancer
  • ivermectin synergizes with the chemotherapy agents cytarabine and daunorubicin to induce cell death in leukemia cells
  • Ivermectin inhibits proliferation and increases apoptosis of various human cancers
  • Activation of WNT-TCF signaling is implicated in multiple diseases, including cancers of the lungs and intestine,
  • A new screening system has found that ivermectin inhibits the expression of WNT-TCF targets
  • It represses the levels of C-terminal β-catenin phosphoforms and of cyclin D1 in an okadaic acid-sensitive manner, indicating its action involves protein phosphatases
  • In vivo, ivermectin selectively inhibits TCF-dependent, but not TCF-independent, xenograft growth without side effects
  • ivermectin has an exemplary safety record, it could swiftly become a useful tool as a WNT-TCF pathway response blocker to treat WNT-TCF-dependent diseases, encompassing multiple cancers.117
  • Nathan Goodyear on 19 Mar 18
     
    Ivermectin shows promise and usefullness in several cancer types.  This is a review article.
Nathan Goodyear

Testosterone replacement therapy and the risk of prostate cancer - 0 views

www.ncbi.nlm.nih.gov/...PMC4814970

Testosterone testosterone therapy saturation theory cancer prostate cancer male hormones

shared by Nathan Goodyear on 01 Oct 16 - No Cached
  • When the level of circulating androgen is below normal, some androgen receptors are inactive, and the secondary downstream effects are decreased. Once androgen receptors within the prostate are saturated, however, increasing testosterone will no longer have an effect
  • the saturation point is thought to occur at low physiologic testosterone levels
  • Only the subset of individuals with pretreatment testosterone level &lt;250 ng dl−1 had PSA level correlating with free and total testosterone level
  • ...7 more annotations...
  • none of the men stopped testosterone supplementation due to prostate cancer recurrence, and none demonstrated cancer progression
  • PSA level did transiently rise in one patient; however, none exceeded a PSA of 1.5 ng ml−1 to raise concern for biochemical recurrence
  • after 19 months on TRT, 10 hypogonadal patients with a history of undergoing a radical retropubic prostatectomy for prostate cancer had no PSA recurrence and had statistically significant improvements in serum total testosterone and hypogonadal symptoms
  • Similarly, Kaufman and Graydon14 examined case records of seven hypogonadal men who had undergone curative RP with symptoms of hypogonadism and low serum testosterone levels treated with testosterone replacement. No biochemical or clinical evidence of cancer recurrence was noted
  • In a much larger case series, Khera et al.15 reviewed the records of 57 men who received TRT following RP. After an average of 36 months following RP, testosterone replacement was initiated and followed for an average of 13 months. Mean testosterone values rose significantly and once again, there was no increase in PSA values and, therefore, no diagnosed biochemical recurrence
  • Four of the patients in the treatment group were found to have cancer recurrence, compared with eight in the control group
  • All biochemical recurrences were seen in individuals with high-risk disease
  • Nathan Goodyear on 01 Oct 16
     
    Good review of data on Testosterone therapy and prostate cancer risk: the take home is there is no increased risk.  Also, included is a discussion of the prostate saturation theory.
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

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

Immunotherapy for Prostate Cancer with Gc Protein-Derived Macrophage-Activating Factor,... - 0 views

europepmc.org/...PMC2510818

GC-MAF Nagalase cancer prostate cancer immunotherapy PSA

shared by Nathan Goodyear on 08 May 18 - No Cached
  • the MAF precursor activity of prostate cancer patient Gc protein is lost or reduced, because their serum Gc protein is deglycosylated by serum α-N-acetylgalactosaminidase (Nagalase) secreted from cancerous cells
  • Administration of 100 ng of GcMAF
  • 100 ng of GcMAF was administered intramuscularly once a week
  • ...11 more annotations...
  • As GcMAF therapy progressed the MAF precursor activity of all five patients increased and their serum Nagalase activity decreased inversely
  • As GcMAF therapy progressed, the MAF precursor activity increased with a concomitant decrease in serum Nagalase activity
  • serum Nagalase is proportional to tumor burden
  • as GcMAF therapy progressed, serum Nagalase activity decreased and, concomitantly, tumor burden decreased
  • the serum Nagalase activities of all 16 patients decreased as GcMAF therapy progressed
  • annual computed tomographic scans of these patients confirmed them being tumor recurrence-free for the 7 years
  • undifferentiated cells were killed rapidly during the first few weeks, and the differentiated cells were killed slowly in the remaining GcMAF therapeutic period
  • PSA levels of prostatectomized patients decreased as serum Nagalase decreased during GcMAF therapy
  • In patients without tumor resection, however, although serum Nagalase activity decreased as GcMAF therapy progressed, their PSA values remained unchanged. The result suggests that the PSA derived from tumor-bearing prostate did not change while tumor burden decreased. Because tumor-induced inflammation in the noncancerous prostate tissues causes secretion of PSA [38], the PSA produced from these inflamed noncancerous prostate tissues cannot be changed by the decrease in tumor burden
  • Advanced cancer patients have high serum Nagalase activities, resulting in no macrophage activation and severe immunosuppression that explain why cancer patients die with overwhelming infection
  • Prognostic utility of serum α-N-acetylgalactosaminidase and immunosuppression resulted from deglycosylation of serum Gc protein in oral cancer patients
  • Nathan Goodyear on 08 May 18
     
    GC-MAF levels exist in inverse relationship to nagalase.  In this study of men with prostate cancer, weekly GCMAF injections reduced Nagalase activity to levels found in healthy controls suggesting tumor free. The dose was 100 ng/week. Nagalase is a protein that suppresses GC-MAF production and thus is immunosuppressive.
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