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Nathan Goodyear

Growth Inhibition of Ovarian Tumor-Initiating Cells by Niclosamide | Molecular Cancer T... - 0 views

  • Ovarian cancer is the most lethal gynecologic malignancy and the fifth-most cause of overall cancer death of women in developed countries
  • An increasingly accepted cancer stem cell hypothesis regards tumors as caricatures of normal organs, possessing a hierarchy of cell types, at various stages of aberrant differentiation, descended from precursor tumor-initiating cells (TIC) cells that are highly resistant to conventional cytotoxics
  • Significant changes of gene expression in 2,928 genes were identified after niclosamide treatment for different time periods
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  • uncoupling of mitochondrial oxidative phosphorylation is believed to be its anti-helminthic mechanism of action
  • we hypothesized that niclosamides antagonistic effects on OTICs could, in part, be due to its disruption of metabolism
  • niclosamide represses metabolic enzymes responsible for bioenergetics, biosynthesis, and redox regulation specifically in OTICs, presumably leading to mitochondrial intrinsic apoptosis pathways, loss of tumor stemness, and growth inhibition
  • niclosamide treatment resulted in a more than 20% increase in reactive oxygen species (ROS) in cultured OTICs
  • niclosamide, which has proved to be safe and effective for the past 2 decades against numerous parasites, inhibited OTIC growth both in vitro and in vivo
  • Our results showed that genes participating in protein complexes of oxidative phosphorylation were downregulated
  • Niclosamide is believed to inhibit mitochondrial oxidative phosphorylation
  • Niclosamide was reported to inactivate NF-κB, causing mitochondrial damage and the generation of ROS, leading to apoptosis of leukemic stem cells
  • niclosamide were identified in a screen for mTOR-signaling inhibitors
  • mTOR was reported to maintain stemness properties of HSCs by inhibiting mitochondrial biogenesis and ROS levels (39), implying that mTOR inhibitors (such as niclosamide) may interfere with mitochondria and various metabolic pathways in TICs via disruption of antioxidant responses
  • We observed Wnt hyperactivity in OTICs, in agreement with previous hypotheses of Wnt inhibitor effectiveness as an ovarian cancer therapy
  • niclosamide has now been independently identified in screens for Wnt inhibitors
  • downregulation of the Wnt/β-catenin target oncogenes survivin and c-Myc
  • ovarian carcinogenesis, the cell-to-cell signaling pathway Notch (8), were also suppressed by niclosamide (data not shown). These results agree with another recent niclosamide study in leukemia (49), and it has been widely hypothesized that disruption of Notch signaling may represent a highly effective therapy for ovarian and other solid tumors, via its essentiality to maintaining TIC stemness
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    Niclosamide, common anti-parasitic medication, inhibits cellular metabolism and increases ROS; both of which provide powerful anti-proliferative, anti-cancer treatment mechanism in TICs. Powerful target therapy for cancer stem cells. Also shown to inhibit Wnt stimulated oncogenes survivin and c-Myc, disrupts Notch signaling, inactivates NF-kappaBeta, and inhibits mTOR-signaling.  This has been found in in vitro and in vivo studies.
Nathan Goodyear

Press-pulse: a novel therapeutic strategy for the metabolic management of cancer | Nutr... - 0 views

  • A “press” disturbance was considered a chronic environmental stress on all organisms in an ecological community
  • “pulse” disturbances were considered acute events that disrupted biological communities to produce high mortality
  • Neoplasia involving dysregulated cell growth is the biological endpoint of the disease
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  • Data from the American Cancer Society show that the rate of increase in cancer deaths/year (3.4%) was two-fold greater than the rate of increase in new cases/year (1.7%) from 2013 to 2017
  • cancer is predicted to overtake heart disease as the leading cause of death in Western societies
  • cancer can also be recognized as a metabolic disease.
  • glucose is first split into two molecules of pyruvate through the Embden–Meyerhof–Parnas glycolytic pathway in the cytosol
  • Aerobic fermentation, on the other hand, involves the production of lactic acid under normoxic conditions
  • persistent lactic acid production in the presence of adequate oxygen is indicative of abnormal respiration
  • Otto Warburg first proposed that all cancers arise from damage to cellular respiration
  • The Crabtree effect is an artifact of the in vitro environment and involves the glucose-induced suppression of respiration with a corresponding elevation of lactic acid production even under hyperoxic (pO2 = 120–160 mmHg) conditions associated with cell culture
  • the Warburg theory of insufficient aerobic respiration remains as the most credible explanation for the origin of tumor cells [2, 37, 51, 52, 53, 54, 55, 56, 57].
  • The main points of Warburg’s theory are; 1) insufficient respiration is the predisposing initiator of tumorigenesis and ultimately cancer, 2) energy through glycolysis gradually compensates for insufficient energy through respiration, 3) cancer cells continue to produce lactic acid in the presence of oxygen, and 4) respiratory insufficiency eventually becomes irreversible
  • Efraim Racker coined the term “Warburg effect”, which refers to the aerobic glycolysis that occurs in cancer cells
  • Warburg clearly demonstrated that aerobic fermentation (aerobic glycolysis) is an effect, and not the cause, of insufficient respiration
  • all tumor cells that have been examined to date contain abnormalities in the content or composition of cardiolipin
  • The evidence supporting Warburg’s original theory comes from a broad range of cancers and is now overwhelming
  • respiratory insufficiency, arising from any number mitochondrial defects, can contribute to the fermentation metabolism seen in tumor cells.
  • data from the nuclear and mitochondrial transfer experiments suggest that oncogene changes are effects, rather than causes, of tumorigenesis
  • Normal mitochondria can suppress tumorigenesis, whereas abnormal mitochondria can enhance tumorigenesis
  • In addition to glucose, cancer cells also rely heavily on glutamine for growth and survival
  • Glutamine is anapleurotic and can be rapidly metabolized to glutamate and then to α-ketoglutarate for entry into the TCA cycle
  • Glucose and glutamine act synergistically for driving rapid tumor cell growth
  • Glutamine metabolism can produce ATP from the TCA cycle under aerobic conditions
  • Amino acid fermentation can generate energy through TCA cycle substrate level phosphorylation under hypoxic conditions
  • Hif-1α stabilization enhances aerobic fermentation
  • targeting glucose and glutamine will deprive the microenvironment of fermentable fuels
  • Although Warburg’s hypothesis on the origin of cancer has created confusion and controversy [37, 38, 39, 40], his hypothesis has never been disproved
  • Warburg referred to the phenomenon of enhanced glycolysis in cancer cells as “aerobic fermentation” to highlight the abnormal production of lactic acid in the presence of oxygen
  • Emerging evidence indicates that macrophages, or their fusion hybridization with neoplastic stem cells, are the origin of metastatic cancer cells
  • Radiation therapy can enhance fusion hybridization that could increase risk for invasive and metastatic tumor cells
  • Kamphorst et al. in showing that pancreatic ductal adenocarcinoma cells could obtain glutamine under nutrient poor conditions through lysosomal digestion of extracellular proteins
  • It will therefore become necessary to also target lysosomal digestion, under reduced glucose and glutamine conditions, to effectively manage those invasive and metastatic cancers that express cannibalism and phagocytosis.
  • Previous studies in yeast and mammalian cells show that disruption of aerobic respiration can cause mutations (loss of heterozygosity, chromosome instability, and epigenetic modifications etc.) in the nuclear genome
  • The somatic mutations and genomic instability seen in tumor cells thus arise from a protracted reliance on fermentation energy metabolism and a disruption of redox balance through excess oxidative stress.
  • According to the mitochondrial metabolic theory of cancer, the large genomic heterogeneity seen in tumor cells arises as a consequence, rather than as a cause, of mitochondrial dysfunction
  • A therapeutic strategy targeting the metabolic abnormality common to most tumor cells should therefore be more effective in managing cancer than would a strategy targeting genetic mutations that vary widely between tumors of the same histological grade and even within the same tumor
  • Tumor cells are more fit than normal cells to survive in the hypoxic niche of the tumor microenvironment
  • Hypoxic adaptation of tumor cells allows for them to avoid apoptosis due to their metabolic reprograming following a gradual loss of respiratory function
  • The high rates of tumor cell glycolysis and glutaminolysis will also make them resistant to apoptosis, ROS, and chemotherapy drugs
  • Despite having high levels of ROS, glutamate-derived from glutamine contributes to glutathione production that can protect tumor cells from ROS
    • Nathan Goodyear
       
      reason to eliminate glutamine in cancer patients and even GSH with cancer patients
  • It is clear that adaptability to environmental stress is greater in normal cells than in tumor cells, as normal cells can transition from the metabolism of glucose to the metabolism of ketone bodies when glucose becomes limiting
  • Mitochondrial respiratory chain defects will prevent tumor cells from using ketone bodies for energy
  • glycolysis-dependent tumor cells are less adaptable to metabolic stress than are the normal cells. This vulnerability can be exploited for targeting tumor cell energy metabolism
  • In contrast to dietary energy reduction, radiation and toxic drugs can damage the microenvironment and transform normal cells into tumor cells while also creating tumor cells that become highly resistant to drugs and radiation
  • Drug-resistant tumor cells arise in large part from the damage to respiration in bystander pre-cancerous cells
  • Because energy generated through substrate level phosphorylation is greater in tumor cells than in normal cells, tumor cells are more dependent than normal cells on the availability of fermentable fuels (glucose and glutamine)
  • Ketone bodies and fats are non-fermentable fuels
  • Although some tumor cells might appear to oxidize ketone bodies by the presence of ketolytic enzymes [181], it is not clear if ketone bodies and fats can provide sufficient energy for cell viability in the absence of glucose and glutamine
  • Apoptosis under energy stress is greater in tumor cells than in normal cells
  • A calorie restricted ketogenic diet or dietary energy reduction creates chronic metabolic stress in the body
  • . This energy stress acts as a press disturbance
  • Drugs that target availability of glucose and glutamine would act as pulse disturbances
  • Hyperbaric oxygen therapy can also be considered another pulse disturbance
  • The KD can more effectively reduce glucose and elevate blood ketone bodies than can CR alone making the KD potentially more therapeutic against tumors than CR
  • Campbell showed that tumor growth in rats is greater under high protein (>20%) than under low protein content (<10%) in the diet
  • Protein amino acids can be metabolized to glucose through the Cori cycle
  • The fats in KDs used clinically also contain more medium chain triglycerides
  • Calorie restriction, fasting, and restricted KDs are anti-angiogenic, anti-inflammatory, and pro-apoptotic and thus can target and eliminate tumor cells through multiple mechanisms
  • Ketogenic diets can also spare muscle protein, enhance immunity, and delay cancer cachexia, which is a major problem in managing metastatic cancer
  • GKI values of 1.0 or below are considered therapeutic
  • The GKI can therefore serve as a biomarker to assess the therapeutic efficacy of various diets in a broad range of cancers.
  • It is important to remember that insulin drives glycolysis through stimulation of the pyruvate dehydrogenase complex
  • The water-soluble ketone bodies (D-β-hydroxybutyrate and acetoacetate) are produced largely in the liver from adipocyte-derived fatty acids and ketogenic dietary fat. Ketone bodies bypass glycolysis and directly enter the mitochondria for metabolism to acetyl-CoA
  • Due to mitochondrial defects, tumor cells cannot exploit the therapeutic benefits of burning ketone bodies as normal cells would
  • Therapeutic ketosis with racemic ketone esters can also make it feasible to safely sustain hypoglycemia for inducing metabolic stress on cancer cells
    • Nathan Goodyear
       
      Ketones are much more than energy adaptabilit, but actually are therapeutic.
  • ketone bodies can inhibit histone deacetylases (HDAC) [229]. HDAC inhibitors play a role in targeting the cancer epigenome
  • Therapeutic ketosis reduces circulating inflammatory markers, and ketones directly inhibit the NLRP3 inflammasome, an important pro-inflammatory pathway linked to carcinogenesis and an important target for cancer treatment response
  • Chronic psychological stress is known to promote tumorigenesis through elevations of blood glucose, glucocorticoids, catecholamines, and insulin-like growth factor (IGF-1)
  • In addition to calorie-restricted ketogenic diets, psychological stress management involving exercise, yoga, music etc. also act as press disturbances that can help reduce fatigue, depression, and anxiety in cancer patients and in animal models
  • Ketone supplementation has also been shown to reduce anxiety behavior in animal models
  • This physiological state also enhances the efficacy of chemotherapy and radiation therapy, while reducing the side effects
  • lower dosages of chemotherapeutic drugs can be used when administered together with calorie restriction or restricted ketogenic diets (KD-R)
  • Besides 2-DG, a range of other glycolysis inhibitors might also produce similar therapeutic effects when combined with the KD-R including 3-bromopyruvate, oxaloacetate, and lonidamine
    • Nathan Goodyear
       
      oxaloacetate is a glycolytic inhibitor, as is doxycycline, and IVC.
  • A synergistic interaction of the KD diet plus radiation was seen
  • It is important to recognize, however, that the radiotherapy used in glioma patients can damage the respiration of normal cells and increase availability of glutamine in the microenvironment, which can increase risk of tumor recurrence especially when used together with the steroid drug dexamethasone
  • Poff and colleagues demonstrated that hyperbaric oxygen therapy (HBOT) enhanced the ability of the KD to reduce tumor growth and metastasis
  • HBOT also increases oxidative stress and membrane lipid peroxidation of GBM cells in vitro
  • The effects of the KD and HBOT can be enhanced with administration of exogenous ketones, which further suppressed tumor growth and metastasis
  • Besides HBOT, intravenous vitamin C and dichloroacetate (DCA) can also be used with the KD to selectively increase oxidative stress in tumor cells
  • Recent evidence also shows that ketone supplementation may enhance or preserve overall physical and mental health
  • Some tumors use glucose as a prime fuel for growth, whereas other tumors use glutamine as a prime fuel [102, 186, 262, 263, 264]. Glutamine-dependent tumors are generally less detectable than glucose-dependent under FDG-PET imaging, but could be detected under glutamine-based PET imaging
  • GBM and use glutamine as a major fuel
  • Many of the current treatments used for cancer management are based on the view that cancer is a genetic disease
  • Emerging evidence indicates that cancer is a mitochondrial metabolic disease that depends on availability of fermentable fuels for tumor cell growth and survival
  • Glucose and glutamine are the most abundant fermentable fuels present in the circulation and in the tumor microenvironment
  • Low-carbohydrate, high fat-ketogenic diets coupled with glycolysis inhibitors will reduce metabolic flux through the glycolytic and pentose phosphate pathways needed for synthesis of ATP, lipids, glutathione, and nucleotides
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    Cancer is a mitochondrial disease? So says the well published Dr Seyfried. Glucose and glutamine drive cancer growth.
Nathan Goodyear

Oncotarget | Vitamin C and Doxycycline: A synthetic lethal combination therapy targetin... - 0 views

  • These eight distinct cancer types included: DCIS, breast (ER(+) and ER(-)), ovarian, prostate, lung, and pancreatic carcinomas, as well as melanoma and glioblastoma. Doxycycline was also effective in halting the propagation of primary cultures of CSCs from breast cancer patients, with advanced metastatic disease (isolated from ascites fluid and/or pleural effusions)
  • Doxycycline behaves as a strong radio-sensitizer, successfully overcoming radio-resistance in breast CSCs
  • cancer cells can indeed escape the effects of Doxycycline, by reverting to a purely glycolytic phenotype. Fortunately, the metabolic inflexibility conferred by this escape mechanism allows Doxycycline-resistant (DoxyR) CSCs to be more effectively targeted with many other metabolic inhibitors, including Vitamin C, which functionally blocks aerobic glycolysis
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  • Vitamin C inhibits GAPDH (a glycolytic enzyme) and depletes the cellular pool of glutathione, resulting in high ROS production and oxidative stress
  • DoxyR CSCs are between 4- to 10-fold more susceptible to the effects of Vitamin C
  • Doxycycline and Vitamin C may represent a new synthetic lethal drug combination for eradicating CSCs, by ultimately targeting both mitochondrial and glycolytic metabolism
  • inhibiting their propagation in the range of 100 to 250 µM
  • metabolic flexibility in cancer cells allows them to escape therapeutic eradication, leading to chemo- and radio-resistance
  • used doxycycline to pharmacologically induce metabolic inflexibility in CSCs, by chronically inhibiting mitochondrial biogenesis
  • This treatment resulted in a purely glycolytic population of surviving cancer cells
  • DoxyR cells are mainly glycolytic
  • MCF7 cells survive and develop Doxycycline-resistance, by adopting a purely glycolytic phenotype
  • Cancer stem cells (CSCs) are thought to be the “root cause” of tumor recurrence, distant metastasis and therapy-resistance
  • the conserved evolutionary similarities between aerobic bacteria and mitochondria, certain classes of antibiotics inhibit mitochondrial protein translation, as an off-target side-effect
  • Vitamin C was more potent than 2-DG; it inhibited DoxyR CSC propagation by > 90% at 250 µM and 100% at 500 µM
  • IC-50
  • DoxyR CSCs are between 4- to 10-fold more sensitive to Vitamin C than control MCF7 CSCs
  • Berberine, which is a naturally occurring antibiotic that also behaves as an OXPHOS inhibitor
  • treatment with Berberine effectively inhibited the propagation of the DoxyR CSCs by > 50% at 1 µM and > 80% at 10 µM.
  • Doxycycline, a clinically approved antibiotic, induces metabolic stress in cancer cells. This allows the remaining cancer cells to be synchronized towards a purely glycolytic phenotype, driving a form of metabolic inflexibility
  • Doxycycline-driven aerobic glycolysis
  • new synthetic lethal strategy for eradicating CSCs, by employing i) Doxycycline (to target mitochondria) and ii) Vitamin C (to target glycolysis)
  • Doxycycline inhibits mitochondrial biogenesis and OXPHOS,
  • hibits glycolytic metabolism by targeting and inhibiting the enzyme GAPDH
  • CSCs act as the main promoter of tumor recurrence and patient relapse
  • a metabolic shift from oxidative to glycolytic metabolism represents an escape mechanism for breast cancer cells chronically-treated with a mitochondrial stressor like Doxycycline, as mitochondrial dys-function leads to a stronger dependence on glucose
  • Vitamin C has been demonstrated to selectively kill cancer cells in vitro and to inhibit tumor growth in experimental mouse models
  • many of these actions have been attributed to the ability of Vitamin C to act as a glycolysis inhibitor, by targeting GAPDH and depleting the NAD pool
  • here we show that DoxyR CSCs are more vulnerable to the inhibitory effects of Vitamin C, at 4- to 10-fold lower concentrations, between 100 to 250 μM
  • concurrent use of Vitamin C, with standard chemotherapy, reduces tumor recurrence and patient mortality
  • after oral administration, Vitamin C plasma levels reach concentrations of ~70-220 μM
  • intravenous administration results in 30- to 70- fold higher plasma concentrations of Vitamin C
  • pro-oxidant activity results from Vitamin C’s action on metal ions, which generates free radicals and hydrogen peroxide, and is associated with cell toxicity
  • it has been shown that high-dose Vitamin C is more cytotoxic to cancer cells than to normal cells
  • This selectivity appears to be due to the higher catalase content observed in normal cells (~10-100 fold greater), as compared to tumor cells. Hence, Vitamin C may be regarded as a safe agent that selectively targets cancer cells
  • the concurrent use of Doxycycline and Vitamin C, in the context of this infectious disease, appeared to be highly synergistic in patients
  • Goc et al., 2016, showed that Doxycycline is synergistic in vitro with certain phytochemicals and micronutrients, including Vitamin C, in the in vitro killing of the vegetative spirochete form of Borrelia spp., the causative agent underlying Lyme disease
  • Doxycycline, an FDA-approved antibiotic, behaves as an inhibitor of mitochondrial protein translation
  • CSCs successfully escape from the anti-mitochondrial effects of Doxycycline, by assuming a purely glycolytic phenotype. Therefore, DoxyR CSCs are then more susceptible to other metabolic perturbations, because of their metabolic inflexibility
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    Not especially new, but IV vitamin C + daily doxycycline found to kill cancer stem cells.
Nathan Goodyear

High-dose ascorbic acid synergizes with anti-PD1 in a lymphoma mouse model - 0 views

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    high dose vitamin C shown to augment PD-1 immune check point inhibitors in Lymphoma mouse model.
Nathan Goodyear

Phosphodiesterase 4D Inhibitors Limit Prostate Cancer Growth Potential - 0 views

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    PDE inhibitors increase cAMP and useful to inhibit invasion and mobility of prostate cancer.
Nathan Goodyear

Inhibitors of phosphodiesterase as cancer therapeutics - ScienceDirect - 0 views

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    PDE inhibit various stages of oncogenic transformation, growth, and metastasis through increase in cAMP.
Nathan Goodyear

Frontiers | Nicotinamide, a Poly [ADP-Ribose] Polymerase 1 (PARP-1) Inhibitor, as an Ad... - 0 views

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    Nicotinamide is a PARP1 inhibitor.
Nathan Goodyear

[Enhancing Antitumor Effects Using Hyperthermia(Including Immune Checkpoint Inhibitor)]... - 0 views

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    Only abstract available here. Hyperthermia augments radiation, chemotherapy, and checkpoint inhibitors.
Nathan Goodyear

Progesterone-induced stimulation of mammary tumorigenesis is due to the proge... - 0 views

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    5 alpha reductase inhibitor, finasteride inhibits pro-tumor progesterone metabolite pathway.
Nathan Goodyear

The Red Wine Polyphenol Resveratrol Displays Bilevel Inhibition on Aromatase in Breast ... - 0 views

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    resveratrol in red wine is an aromatase inhibitor.
Nathan Goodyear

Anti-Aromatase Chemicals in Red Wine - ENG - 2006 - Annals of the New York Academy of S... - 0 views

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    resveratrol in red wine acts as aromatase inhibitor.  
Nathan Goodyear

Efficacy of tablet huperzine-A on memory, cognition, and behavior in Alzheimer's disease - 0 views

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    small study, but well designed that showed that huperzine A supplementation improved executive function in Alzheimer's patients. Huperzine A is an acetylcholinesterase inhibitor.
Nathan Goodyear

Cognitive dysfunction in postmenopausal breast cancer patients on aromatase inhibitors,... - 0 views

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    Just the abstract here.  Declining estradiol production found to be associated with increased cognitive dysfunction or cognitive decline in those using aromatase inhibitor therapy.  Aromatase inhibition therapy is used to block Testosterone to Estradiol production in women with ER+ breast cancer.
Nathan Goodyear

Selective aromatase inhibition for patients with androgen-independent prostate carcinom... - 0 views

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    study finds little benefit from third generation aromatase inhibitor in reducing PSA.
Nathan Goodyear

Testosterone replacement in prostate cancer survivors with hypogonadal symptoms - Leibo... - 0 views

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    Good article.  This article (case series) found that 40% of the men included had no increase in PSA with Testosterone.  One point on the Testosterone dosage is that they used androgen, which is an overdose of Testosterone.  That gives 60% that the PSA did increase.  These men had higher PSA to begin with which leads to the suggestion that the prostate cells were abnormal.  Those men that had a prostatectomy were more likely to have little if any increase in PSA.  This study did use a the 5 alpha reductase inhibitor dutasteride.
Nathan Goodyear

JAMA Network | JAMA Internal Medicine | Sildenafil Use and Increased Risk of ... - 0 views

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    Viagra associated with a 84% increased risk of melanoma.  The key word here is associated.  No cause and effect relationship is seen.  Anytime use was also associated with increased risk.  This study did not look at the other phopsphodiesterase 5 inhibitors, though the logic is there risk may be higher as they are longer acting.
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