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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

Sex hormones affect neurotransmitters and shape the adult female brain during hormonal ... - 0 views

  • estrogen administration has been found to increase tryptophan hydroxylase
  • 5-HT2A mRNA levels in brain areas relevant for the control of mood, mental state and cognition (Sumner and Fink, 1998) and 5-HTT mRNA when administered for a longer period
  • n the other hand, estrogen treatment has also been observed to decrease mRNA related to serotonergic neurotransmission
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  • Furthermore, acute estrogen administration decreases 5-HTT mRNA levels (Pecins-Thompson et al., 1998) and 5-HT1A mRNA levels and binding
  • assigning the effects of estrogen on serotonin to a homogenous functional class of stimulation or inhibition seems not to be feasible
  • Progesterone has been suggested to increase serotonergic neurotransmission via the regulation of the expression of serotonin-related genes and proteins
  • menopausal women gain less benefit from antidepressant treatments compared to women during their reproductive years
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    good review of the relationship of the sex hormones and neurotransmitters.
Nathan Goodyear

Cross-kingdom inhibition of breast cancer growth by plant miR159 - 0 views

  • MicroRNAs (miRNAs), a major family of small RNAs, are ∼23 nt-long single strands of RNA that bind to mRNA transcripts to inhibit their translation
  • A recent study by Zhang et al. reported that plant-derived miRNAs can be found in human serum.
  • The group demonstrates that the plant miRNA miR168 may be taken up through dietary intake to inhibit the expression of its target low-density lipoprotein receptor 1 in the liver21, providing the first evidence that miRNA in food may influence gene expression in mammalian organs.
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  • A more recent finding by the same group shows that a plant miRNA from honeysuckle is able to inhibit Influenza A replication22, indicating that plant miRNAs may be useful for treating human diseases.
  • We found that plant miR159 could be detected in human sera and its levels were inversely correlated with BC incidence and progression.
  • We further identified TCF7 as a mammalian target for miR159 and showed the anti-proliferative function of miR159 in BC cells using in vitro and in vivo models, demonstrating for the first time that a plant miRNA is able to influence BC cell growth.
  • certain dietary miRNAs from plants and other species may serve as highly affordable and powerful means of treatment with minimal inconvenience to patients.
  • miR159 which (using a synthetic mimic) targets TCF7 to inhibit the proliferation of cells whose growth is dependent on TCF7 such as the BC cells MDA-MB-231
  • our study using a BC model clearly indicates the anti-tumor effect of orally administered synthetic miR159 in its naturally existing form with the plant-specific 2'-O-methylation, suggesting the feasibility of using synthetic forms of plant miRNAs as dietary supplements in the treatment of human cancers, including those outside of the GI track
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    Plant microRNA found to exist in human serum from gut absorption to then alter genetic expression in in-vitro and in vivo studies.
Nathan Goodyear

Fructose-1,6-bisphosphate couples glycolytic flux to activation of Ras | Nature Communi... - 0 views

  • glucose deprivation triggers apoptosis47 and vitamin C treatment kills RAS-oncogene expressing tumor cells, but not wild-type RAS containing cells, by inhibition of GAPDH
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    New study out of the UK supports the role of glucose in cancer growth and aggressiveness.  This research found that high influx of glucose into the glycolysis pathway upregulated the RAS oncogene via accumulation of the Fructose 1,6 bisphosphonate through the enzyme phosphofructokinase..
Nathan Goodyear

Quercetin induces apoptosis by activating caspase-3 and regulating Bcl-2 and cyclooxyge... - 0 views

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    quercetin down-regulated the expression of anti-apoptosis protein Bcl-2 and up-regulated the expression of pro-apoptosis protein Bax. Caspase-3 was also activated by quercetin, which started a caspase-3-depended mitochodrial pathway to induce apoptosis. It was also found that quercetin inhibited the expression of the cycloocygenase-2
Nathan Goodyear

Face masks to prevent community transmission of viral respiratory infections: A rapid e... - 0 views

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    Largest meta-analysis to date shows facemasks don't work. Yet, they pro-facemasks claim to have science on their side. Simply saying evidence-based doesn't not cut it.
indiacardiacsurg

French Health Trip To India: Un chirurgien cardiaque pour enfants en Inde cré... - 0 views

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    De plus, le chirurgien cardiaque pour enfants en Inde offre un taux de réussite de 99,6% car il est effectué à l'aide de la technologie la plus avancée, à la hauteur de ce que possèdent même les pays les plus évolués du monde. Obtenez une réponse rapide aux requêtes, appelez-nous simplement au +91-9370586696 ou par e-mail : enquiry@indiacardiacsurgerysite.com
Nathan Goodyear

Tumor regionalization after surgery: Roles of the tumor microenvironment and neutrophil... - 0 views

  • tumor surgery must be carefully considered because the risk of metastasis could be increased by the surgical procedure.
  • NETosis, which is the process of forming neutrophil extracellular traps (NETs)
  • surgery-induced metastasis
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  • surgery per se can promote cancer metastasis through a series of local and systemic events
  • surgery results in a serious wound that disrupts the structural barrier preventing the outspreading of cancer cells, change the properties of the cancer cells and stromal cells remaining in the tumor microenvironment, or impairs the host defense systems against cancers
    • Nathan Goodyear
       
      Key point; add to presentation on surgery and metastasis
  • After the primary tumor is surgically removed, the metastases can start to grow vigorously via neoangiogenesis because the circulating inhibitors disappear
  • infection and inflammation during the postoperative period have been reported to increase the risk of cancer recurrence in patients
  • Surgeons have long suspected that surgery, even if it is a necessary step in cancer treatment, facilitates cancer metastasis
  • Surgery-induced cancer metastasis has been well established in animal models
  • tumor cell dissemination, tumor-favoring immune responses, and neoangiogenesis
  • the surgical resection of primary tumors is beneficial is controversial
  • CTCs abruptly increase just after surgery
  • Even externally palpitating tumors for diagnosis could increase the numbers of CTCs in skin cancer and breast cancer
  • excessive glucocorticoids negatively modulate immune functions
  • immune surveillance against tumors is considered to be impaired by surgical stress
  • In addition to glucocorticoids, during stimulation of the HPA axis, the catecholamine hormones epinephrine and norepinephrine are released from the adrenal medulla
  • NK cell suppression may be attributed to increased levels of catecholamines as well as glucocorticoids
  • In mice bearing a primary tumor, it was observed that the removal of the primary tumor facilitated the growth of highly vascularized metastases
  • primary tumors may secrete angiogenic inhibitors as well as angiogenic activators
  • second phase of tumor recurrence and metastasis, which are newly acquired events, rather than just outcomes of incomplete treatment.
    • Nathan Goodyear
       
      Another key point
  • double-edged sword
  • HIF-1 in neutrophils plays a critical role in NETosis and bacteria-killing activity
  • neutrophils play various roles in the initiation and progression of cancer
  • NETosis
  • many inflammatory and neoplastic diseases
  • formation of neutrophil extracellular traps (NETs), which are large extracellular complexes composed of chromatin and cytoplasmic/granular proteins1
  • NETosis has been highlighted as an inflammatory event that promotes cancer metastasis
  • Once activated, neutrophils produce intracellular precursors by using DNA, histones, and granular and cytoplasmic proteins and then spread the mature form of NETs out around themselves
  • A series of these events is called NETosis.
  • neutrophil elastase, myeloperoxidase, cathepsin G, proteinase 3, lactoferrin, gelatinase, lysozyme C, calprotectin, neutrophil defensins, and cathelicidins
  • innate immune response against infection
  • Neutrophils are the most abundant type of granulocytes, comprising 40–70% of all white blood cells
  • two types of NEToses, suicidal (or lytic) NETosis and vital NETosis
  • Suicidal NETosis mainly depends on the production of reactive oxygen species (ROS)
  • Since neutrophils die during this process, it is called suicidal NETosis.
  • vital NETosis
  • vital NETosis occurs independently of ROS production
  • Vital NETosis can be induced by Gram-negative bacteria. LPS
  • NETs are present in a variety of cancers, such as lung cancer, colon cancer, ovarian cancer, and leukemia
  • neutrophils actively undergo NETosis in the tumor microenvironment
  • Hypoxia
  • NETosis plays a pivotal role in noninfectious autoimmune diseases,
  • cytokines
  • tumor-derived proteases
  • tumor exosomes
  • NETosis generally actively progresses in the tumor microenvironment.
  • the proliferative cytokines TGFβ and IL-10 and the angiogenic factor VEGF are representative of neutrophil-derived tissue repair proteins.
  • NETosis is a defense system to protect the body from invading pathogens
  • when neutrophils are excessively stimulated, they produce excess NETs, thereby leading to pathological consequences
  • plasma levels of NETosis markers are elevated after major surgeries
  • local invasion, intravasation into the blood or lymphatic vessels, escape from the immune system, anchoring to capillaries in target organs, extravasation into the organs, transformation from dormant cells to proliferating cells, colonization to micrometastases, and growth to macrometastases
  • NETs promote metastasis at multiple steps
  • NETs loosen the ECM and capillary wall to promote the intravasation of cancer cells
  • NETs and platelets wrap CTCs, which protects them from attack by immune cells and shearing force by blood flow
  • NETs promote the local invasion of cancer cells by degrading the extracellular matrix (ECM)
  • neutrophil elastase, matrix metalloproteinase 9, and cathepsin G
  • NETs also promote the intravasation of cancer cells
  • millions of tumor cells are released into the circulation every day,
  • NETs can wrap up CTCs with platelets
  • β1-integrin plays an important role in the interaction between CTCs and NETs
  • NET-platelet-CTC aggregates.
  • After metastasizing to distant tissues, tumor cells are often found to remain dormant for a period of time and unexpectedly regrow late
  • NETs are believed to participate in the reactivation of dormant cancer cells in metastatic regions
  • NET-associated proteases NE and MMP-9 were found to be responsible for the reactivation of dormant cancer cells
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    Surgery induced metastasis: it is real and steered by NETosis.
indian-health

Les meilleures cliniques dentaires de New Delhi sont sûres, professionnelles,... - 0 views

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    Chaque année, des milliers de patients du monde entier se rendent à Delhi pour se faire soigner dans les meilleures cliniques dentaires de New Delhi.
indian-health

La chirurgie dentaire en Inde offre le traitement que vous désirez et méritez - 0 views

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    Chaque année, des milliers de patients du monde entier se rendent en Inde pour se faire soigner dans les meilleures cliniques dentaires de New Delhi. Le personnel médical des meilleurs hôpitaux de chirurgie dentaire en Inde est très expérimenté dans le traitement de toutes les formes de cas dentaires
indian-health

Chirurgie cardiaque Inde Préserver et améliorer la santé cardiaque en Inde - 0 views

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    Les coûts de chirurgie cardiaque en Inde sont jusqu'à 50% inférieurs à ceux d'autres pays développés, ce qui fait de l'Inde un choix idéal pour cette procédure.
indian-health

Des sourires heureux et sains pour toujours avec la chirurgie dentaire en Inde - 0 views

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    Les 14 meilleurs chirurgiens dentistes de Delhi traitent des milliers de personnes chaque année, dont la plupart trouvent qu'il est très abordable de se rendre en Inde principalement pour leurs implants dentaires.
spineneuro

French to India Medical Travel: La chirurgie robotique de la colonne vertébra... - 0 views

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    La chirurgie robotique de la colonne vertébrale à faible coût en Inde ne représente qu'une fraction de celle de leurs homologues dans la plupart des pays occidentaux.
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