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Nathan Goodyear

Vitamin C preferentially kills cancer stem cells in hepatocellular carcinoma via SVCT-2... - 0 views

www.nature.com/...s41698-017-0044-8

cancer cancer stem cells liver cancer vitamin C IV vitamin C oncology

shared by Nathan Goodyear on 30 Jan 18 - No Cached
  • Chen et al. have revealed that ascorbate at pharmacologic concentrations (0.3–20 mM) achieved only by intravenously (i.v.) administration selectively kills a variety of cancer cell lines in vitro, but has little cytotoxic effect on normal cells.
  • Ascorbic acid (the reduced form of vitamin C) is specifically transported into cells by sodium-dependent vitamin C transporters (SVCTs)
  • SVCT-1 is predominantly expressed in epithelial tissues
  • ...41 more annotations...
  • whereas the expression of SVCT-2 is ubiquitous
  • differential sensitivity to VC may result from variations in VC flow into cells, which is dependent on SVCT-2 expression.
  • high-dose VC significantly impaired both the tumorspheres initiation (Fig. 4d, e) and the growth of established tumorspheres derived from HCC cells (Fig. 4f, g) in a time-dependent and dose-dependent manner.
  • Hepatocellular carcinoma (HCC)
  • The antioxidant, N-acetyl-L-cysteine (NAC), preventing VC-induced ROS production (a ROS scavenger), completely restored the viability and colony formation among VC-treated cells
  • DNA double-strand damage was found following VC treatment
  • DNA damage was prevented by NAC
  • Interestingly, the combination of VC and cisplatin was even more effective in reducing tumor growth and weight
  • Consistent with the in vitro results, stemness-related genes expressions in tumor xenograft were remarkably reduced after VC or VC+cisplatin treatment, whereas conventional cisplatin therapy alone led to the increase of CSCs
  • VC is one of the numerous common hepatoprotectants.
  • Interestingly, at extracellular concentrations greater than 1 mM, VC induces strong cytotoxicity to cancer cells including liver cancer cells
  • we hypothesized that intravenous VC might reduce the risk of recurrence in HCC patients after curative liver resection.
  • Intriguingly, the 5-year disease-free survival (DFS) for patients who received intravenous VC was 24%, as opposed to 15% for no intravenous VC-treated patients
  • Median DFS time for VC users was 25.2 vs. 18 months for VC non-users
  • intravenous VC use is linked to improved DFS in HCC patients.
  • In this study, based on the elevated expression of SVCT-2, which is responsible for VC uptake, in liver CSCs, we revealed that clinically achievable concentrations of VC preferentially eradicated liver CSCs in vitro and in vivo
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      the authors here made similar mistakes to the Mayo authors i.e. under doses here in this study.  They dosed at only 2 grams IVC.  A woefully low dose of IVC.
  • Additionally, we found that intravenous VC reduced the risk of post-surgical HCC progression in a retrospective cohort study.
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      positive results despite a low dose used.
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      Their comfort zone was 1mM.  They should have targeted 20-40 mM.
  • Three hundred thirty-nine participants (55.3%) received 2 g intravenous VC for 4 or more days after initial hepatectomy
  • As the key protein responsible for VC uptake in the liver, SVCT-2 played crucial roles in regulating the sensitivity to ascorbate-induced cytotoxicity
  • we also observed that SVCT-2 was highly expressed in human HCC samples and preferentially elevated in liver CSCs
  • SVCT-2 might serve as a potential CSC marker and therapeutic target in HCC
  • CSCs play critical roles in regulating tumor initiation, relapse, and chemoresistance
  • we revealed that VC treatment dramatically reduced the self-renewal ability, expression levels of CSC-associated genes, and percentages of CSCs in HCC, indicating that CSCs were more susceptible to VC-induced cell death
  • as a drug for eradicating CSCs, VC may represent a promising strategy for treatment of HCC, alone or particularly in combination with chemotherapeutic drugs
  • In HCC, we found that VC-generated ROS caused genotoxic stress (DNA damage) and metabolic stress (ATP depletion), which further activated the cyclin-dependent kinase inhibitor p21, leading to G2/M phase cell cycle arrest and caspase-dependent apoptosis in HCC cells
  • we demonstrated a synergistic effect of VC and chemotherapeutic drug cisplatin on killing HCC both in vitro and in vivo
  • Intravenous VC has also been reported to reduce chemotherapy-associated toxicity of carboplatin and paclitaxel in patients,38 but the specific mechanism needs further investigation
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      so, exclude the benefit to patients until the exact mechanism of action, which will never be fully elicited?!?!?
  • Our retrospective cohort study also showed that intravenous VC use (2 g) was related to the improved DFS in HCC patients after initial hepatectomy
    • Nathan Goodyear
      Nathan Goodyear on 31 Jan 18
       
      Terribly inadequate dose.  Target is 20-40 mM which other studies have found occur with 50-75 grams of IVC.
  • several clinical trials of high-dose intravenous VC have been conducted in patients with advanced cancer and have revealed improved quality of life and prolonged OS
  • high-dose VC was not toxic to immune cells and major immune cell subpopulations in vivo
  • high recurrence rate and heterogeneity
  • tumor progression, metastasis, and chemotherapy-resistance
  • SVCT-2 was highly expressed in HCC samples in comparison to peri-tumor tissues
  • high expression (grade 2+/3+) of SVCT-2 was in agreement with poorer overall survival (OS) of HCC patients (Fig. 1c) and more aggressive tumor behavior
  • SVCT-2 is enriched in liver CSCs
  • these data suggest that SVCT-2 is preferentially expressed in liver CSCs and is required for the maintenance of liver CSCs.
  • pharmacologic concentrations of plasma VC higher than 0.3 mM are achievable only from i.v. administration
  • The viabilities of HCC cells were dramatically decreased after exposure to VC in dose-dependent manner
  • VC and cisplatin combination further caused cell apoptosis in tumor xenograft
  • These results verify that VC inhibits tumor growth in HCC PDX models and SVCT-2 expression level is associated with VC response
  • qPCR and IHC analysis demonstrated that expression levels of CSC-associated genes and percentages of CSCs in PDXs dramatically declined after VC treatment, confirming the inhibitory role of VC in liver CSCs
  • Nathan Goodyear on 30 Jan 18
     
    IV vitamin C in vitro and in vivo found to "preferentially" eradicate cancer stem cells.  In addition, IV vitamin C was found to be adjunctive to chemotherapy, found to be hepatoprotectant.  This study also looked at SVCT-2, which is the transport protein important in liver C uptake.
Nathan Goodyear

Doxycycline Decreases Tumor Burden in a Bone Metastasis Model of Human Breast Cancer | ... - 0 views

cancerres.aacrjournals.org/...1588

doxycycline cancer breast cancer

shared by Nathan Goodyear on 08 May 18 - No Cached
  • it appears more likely that the effectiveness relies on the properties of doxycycline as an inhibitor of tumor cell proliferation and less on its effect as a MMP inhibitor
  • Our results suggest that doxycycline may be useful not only for the treatment of osteolytic but also for the treatment of osteoblastic bone metastasis
  • A prominent feature of bone metastasis of breast cancer is the uncoupling of bone remodeling
  • ...3 more annotations...
  • doxycycline can improve this to some extent by increasing bone formation
  • the current study clearly demonstrates the benefit of doxycycline when administered from the time of the development of the tumor
  • In conclusion, doxycycline greatly reduced tumor burden and could also compensate for the increased bone resorption frequently associated with bone metastasis from breast cancer
  • Nathan Goodyear on 08 May 18
     
    doxycycline useful in breast cancer animal model to reduce tumor burden through inhibition of tumor cell proliferation and inhibition of MMP.
Nathan Goodyear

Development of PD-1/PD-L1 Pathway in Tumor Immune Microenvironment and Treatment for No... - 0 views

www.nature.com/...srep13110

PD-1 cancer check point inhibitors PD-L1 CLTA-4 immunotherapy

shared by Nathan Goodyear on 20 Apr 18 - No Cached
  • the lack of immunologic control is recognized as a hallmark of cancer currently
  • Programmed death-1 (PD-1) and its ligand PD-L1 play a key role in tumor immune escape and the formation of tumor microenvironment, closely related with tumor generation and development
  • Blockading the PD-1/PD-L1 pathway could reverse the tumor microenvironment and enhance the endogenous antitumor immune responses.
  • ...4 more annotations...
  • environmental factors, living habits, genetic mutations, dysfunction of the immune system and so on
  • special tumor immune microenvironment
  • cytotoxic T lymphocyte-associated antigen 4 (CLTA-4), Programmed death-1 (PD-1) and its ligands PD-L1 (B7H1) and PD-L2 (B7-DC)
  • CTLA-4 regulates T cell activity in the early stage predominantly, and PD-1 mainly limits the activity of T-cell in the tumor microenvironment at later stage of tumor growth
  • Nathan Goodyear on 20 Apr 18
     
    PD-1 to read.
spineneuro

Get the Best Price for Brain Tumor Surgery India With New-Age Technology and ... - 0 views

spineandneurosurgeryhospitalindia.wordpress.com/...hnology-and-expertise%ef%bf%bc

brain tumor brain tumor surgery Best price for brain tumor surgery in India Brain tumor surgery cost

shared by spineneuro on 03 May 22 - No Cached
  • spineneuro on 03 May 22
     
    As an example, a brain tumor surgical procedure approximately charges only USD 6,000-12000 in India in comparison to the international cost of USD 60,000 (nearly 70-80% much less).
Nathan Goodyear

NETosis and Neutrophil Extracellular Traps in COVID-19: Immunothrombosis and Beyond - PMC - 0 views

www.ncbi.nlm.nih.gov/...PMC8924116

cancer NETosis SARS-CoV-2 COVID COVID-19 COVID19 platelets

shared by Nathan Goodyear on 18 Apr 23 - No Cached
  • Pneumonia is a typical symptom of COVID-19 infection, while acute respiratory distress syndrome (ARDS) and multiple organ failure are common in severe COVID-19 patients
  • NETs are important for preventing pathogen invasion, their excessive formation can result in a slew of negative consequences, such as autoimmune inflammation and tissue damage
  • SARS-CoV-2 infection has also been linked to increased neutrophil-to-lymphocyte ratios, which is associated with disease severity and clinical prognosis
  • ...40 more annotations...
  • NETosis is a special form of programmed cell death in neutrophils, which is characterized by the extrusion of DNA, histones, and antimicrobial proteins in a web-like structure known as neutrophil extracellular traps (NETs)
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      Definition
  • increased generation of reactive oxygen species (ROS) is a crucial intracellular process that causes NETosis
  • Another indirect route of SARS-CoV-2-induced NET production is platelet activation
  • When NETs are activated in the circulation, they can also induce hypercoagulability and thrombosis
  • In COVID-19, major NET protein cargos of NETs (i.e., NE, MPO, and histones) are significantly elevated.
  • SARS-CoV-2 can also infect host cells through noncanonical receptors such as C-type lectin receptors
  • Immunopathological manifestations, including cytokine storms and impaired adaptive immunity, are the primary drivers behind COVID-19, with neutrophil infiltration being suggested as a significant cause
  • NETosis and NETs are increasingly recognized as causes of vascular injury
  • SARS-CoV-2 and its components (e.g., spike proteins and viral RNA) attach to platelets and increase their activation and aggregation in COVID-19, resulting in vascular injury and thrombosis, both of which are linked to NET formation
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      Connects SARS-CoV-2 to TLR on Platelets to NETosis to metastasis.
  • NET formation may be caused by activated platelets rather than SARS-CoV-2 itself
  • NETosis, leading to aberrant immunity such as cytokine storms, autoimmune disorders, and immunosuppression.
  • early bacterial coinfections were more prevalent in COVID-19 patients than those infected with other viruses
  • NETosis and NETs may also have a role in the development of post COVID-19 syndromes, including lung fibrosis, neurological disorders, tumor growth, and worsening of concomitant disease
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      NETosis-> tumor growth
  • NETs and other by-products of NETosis have been shown to act as direct inflammation amplifiers. Hyperinflammation
  • “cytokine storm”
  • SARS-CoV-2 drives NETosis and NET formation to allow for the release of free DNA and by-products (e.g., elastases and histones). This may trigger surrounding macrophages and endothelial cells to secrete excessive proinflammatory cytokines and chemokines, which, in turn, enhance NET formation and form a positive feedback of cytokine storms in COVID-19
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      Cycle of hyperinflammation
  • NET release enables self-antigen exposure and autoantibody production, thereby increasing the autoinflammatory response
  • patients with COVID-19 who have higher anti-NET antibodies are more likely to be detected with positive autoantibodies [e.g., antinuclear antibodies (ANA) and anti-neutrophil cytoplasmic antibodies (ANCA)]
  • COVID-19 NETs may act as potential inducers for autoimmune responses
  • have weakened adaptive immunity as well as a high level of inflammation
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      Immunomodulation
  • tumor-associated NETosis and NETs promote an immunosuppressive environment in which anti-tumor immunity is compromised
  • NETs have also been shown to enhance macrophage pyroptosis in sepsis
  • facilitating an immunosuppressive microenvironment
  • persistent immunosuppression may result in bacterial co-infection or secondary infection
  • can enhance this process by interacting with neutrophils through toll-like receptor 4 (TLR4), platelet factor 4 (PF4), and extracellular vesicle-dependent processes
  • NET-induced immunosuppression in COVID-19 in the context of co-existing bacterial infection
  • Following initial onset of COVID-19, an estimated 50% or more of COVID-19 survivors may develop multi-organ problems (e.g., pulmonary dysfunction and neurologic impairment) or have worsening concomitant chronic illness
  • NETs in the bronchoalveolar lavage fluid of severe COVID-19 patients cause EMT in lung epithelial cells
  • decreased E-cadherin (an epithelial marker) expression
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      Leads to emt
  • COVID-19 also has a long-term influence on tumor progression
  • Patients with tumors have been shown to be more vulnerable to SARS-CoV-2 infection and subsequent development of severe COVID-19
  • patients who have recovered from COVID-19 may have an increased risk of developing cancer or of cancer progression and metastasis
  • awaken cancer cells
  • NETs have been shown to change the tumor microenvironment
  • enhance tumor progression and metastasis
  • vitamin C has been tested in phase 2 clinical trials aimed at reducing COVID-19-associated mortality by reducing excessive activation of the inflammatory response
  • vitamin C is an antioxidant that significantly attenuates PMA-induced NETosis in healthy neutrophils by scavenging ROS
  • vitamin C may also inhibit NETosis and NET production in COVID-19
  • Metformin
  • Vitamin C
  • Nathan Goodyear on 18 Apr 23
     
    NETosis intimately involved in progressive COVID, long COVID, autoimmunity, and cancer
spineneuro

List of India's Best 5 Hospitals for Gamma Knife Delivers Precision Treatment for Brain... - 0 views

www.briefingwire.com/...ion-treatment-for-brain-tumors

Gamma Knife best 5 hospitals for gamma knife gamma knife radiosurgery

shared by spineneuro on 23 Mar 22 - No Cached
  • spineneuro on 23 Mar 22
     
    India's best 5 hospitals for Gamma Knife demonstrated tumor control rates near to 100 % for brain tumors less than a centimeter in diameter that was targeted early. "As the proof maintains to mount and show the gamma knife's efficacy, more oncologists are surveilling patients and finding brain tumors earlier-permitting us to be more proactive and to avoid neurological symptoms," says neurologist of India's best 5 hospitals for gamma knife.
spineneuro

Best Hospital for Brain Tumor Surgery Is As Good As Anywhere Else In The Worl... - 0 views

spineandneurosurgeryhospitalindia.wordpress.com/...-as-anywhere-else-in-the-world

Brain Tumor Brain Tumor Surgery best hospital for brain tumor surgery list of India's top brain tumor surgeons

shared by spineneuro on 01 Apr 22 - No Cached
  • spineneuro on 01 Apr 22
     
    As an example, a brain tumor surgical procedure approximately charges only USD 6,000-12000 in India in comparison to the international cost of USD 60,000 (nearly 70-80% much less).
Nathan Goodyear

The human tumor microbiome is composed of tumor type-specific intracellular bacteria | ... - 0 views

www.science.org/...science.aay9189

tumor microenvironment t tumor microbiome cancer

shared by Nathan Goodyear on 11 Jan 23 - No Cached
  • Nathan Goodyear on 11 Jan 23
     
    Fascinating relationship b/t tumors and tumor microbiome.
Nathan Goodyear

Progesterone metabolites in breast cancer - 1 views

erc.endocrinology-journals.org/...717.full

progesterone metabolism tumor tumorigenesis cancer risk growth hormone hormones 5-beta-pregnanediol 5-alpha-pregnanediol 4-pregnenediol 5-alpha reductase

shared by Nathan Goodyear on 20 Feb 12 - No Cached
  • P metabolites produced within breast tissues might be independently active hormones functioning as cancer-promoting or -inhibiting regulatory agents
  • these P metabolites function as independent pro-or anti-cancer autocrine/paracrine hormones that regulate cell proliferation, adhesion, apoptosis and cytoskeletal, and other cell status molecules via novel receptors located in the cell membrane and intrinsically linked to cell signaling pathways
  • only a fraction of all breast cancer patients respond to this estrogen-based therapy and the response is only temporary
  • ...30 more annotations...
  • P serves as the precursor for the major steroid hormones (androgens, estrogens, corticosteroids) produced by the gonadal and adrenal cortical tissues.
  • 5α-pregnane, 5β-pregnane, and 4-pregnene metabolites of P
  • These P-metabolizing enzymes included 5α-reductase, 5β-reductase, 3α-hydroxysteroid oxido-reductase (3α-HSO), 3β-HSO, 20α-HSO, 20β-HSO, 6α(β)-, 11β-, 17-, and 21-hydroxylase, and C17–20-lyase
  • Reduction of P to 5α-pregnanes is catalyzed by 5α-reductase and the direct 5α-reduced metabolite of P is 5α-pregnane-3,20-dione (5αP). The 5α-reductase reaction is irreversible
  • The two 4-pregnenes resulting from direct P conversion are 4-pregnen-3α-ol-20-one (3αHP) and 4-pregnen-20α-ol-3-one (20αHP), catalyzed by the actions of 3α-HSO and 20α-HSO respectively
  • the P-metabolizing enzyme activities identified in human breast tissues and cell lines were: 5α-reductase, 3α-HSO, 3β-HSO, 20α-HSO, and 6α-hydroxylase
  • In normal breast tissue, conversion to 4-pregnenes greatly exceeded the conversion to 5α-pregnanes, whereas in tumorous tissue, conversion to 5α-pregnanes greatly exceeded that to 4-pregnenes
  • The results indicated that P 5α-reductase activity is significantly higher, whereas P 3α-HSO and 20α-HSO activities are significantly lower in tumor than in normal tissues
  • he results showed that production of 5α-pregnanes was higher and that of 4-pregnenes was lower in tumorigenic (e.g. MCF-7) than in nontumorigenic (e.g. MCF-10A) cells (Fig. 3c⇑), while differences in ER/P status did not appear to play a role
  • The 5α-pregnane-to-4-pregnene ratios were 7- to 20-fold higher in the tumorigenic than in the nontumorigenic cell lines
  • altered direction in P metabolism, and hence in metabolite ratios, was due to significantly elevated 5α-reductase and depressed 3α- and 20α-HSO activities in breast tumor tissues and tumorigenic cells. It appeared, therefore, that changes in P-metabolizing enzyme activities might be related to the shift toward mammary cell tumorigenicity and neoplasia
  • In vivo, changes in enzyme activity can result from changes in levels of the enzyme due to changes in expression of the mRNA coding for the enzyme, or from changes in the milieu in which the enzyme operates (such as temperature and pH, and concentrations of cofactors, substrates, products, competitors, ions, phospholipids, and other molecules)
  • Overall, the enzyme activity and expression studies strongly suggest that 5α-reductase stimulation and 3α- and 20α-HSO suppression are associated with the transition from normalcy to cancer of the breast
  • The level of expression of 5α-reductase is up-regulated by estradiol and P in the uterus (Minjarez et al. 2001) and by 5α-dihydrotestosterone (DHT) in the prostate
  • 3αHP inhibited whereas 5αP-stimulated proliferation
  • Stimulation in cell numbers was also observed when cells were treated with other 5α-pregnanes, such as 5α-pregnan-3α-ol-20-one, 5α-pregnan-20α-ol-3-one, and 5α-pregnane-3α,20α-diol, whereas other 4-pregnenes such as 20α-HP and 4-pregnene-3α,20α-diol resulted in suppression of cell proliferation
  • Stimulation of cell proliferation with 5αP and inhibition with 3αHP were also observed in all other breast cell lines examined, whether ER/P-negative (MCF-10A, MDA-MB-231) or ER/P-positive (T47D, ZR-75-1) and whether requiring estrogen for tumorigenicity (MCF-7, T47D) or not (MDA-MB-231), or whether they are nontumorigenic (
  • αHP resulted in significant increases in apoptosis and decreases in mitosis, leading to significant decreases in total cell numbers. In contrast, treatment with 5αP resulted in decreases in apoptosis and increases in mitosis.
  • The opposing actions of 5αP and 3αHP on both cell anchorage and proliferation strengthen the hypothesis that the direction of P metabolism in vivo toward higher 5α-pregnane and lower 4-pregnene concentrations could promote breast neoplasia and lead to malignancy.
  • he effects on proliferation and adhesion were not due to P, but due to the 5α-reduced metabolites
  • The studies showed that binding of 5αP or 3αHP occurs in the plasma membrane fractions, but not in the nuclear or cytosolic compartments
  • separate high-specificity, high-affinity, low- capacity receptors for 5αP and 3αHP that are distinct from each other and from the well-studied nuclear/cytosolic P, estrogen, and androgen and corticosteroid receptors
  • The studies thus provided the first demonstration of the existence of specific P metabolite receptors
  • the receptor results suggest that the putative tumorigenic actions of 5αP may be significantly augmented by the estradiol-induced increases in 5αP binding and decreases in 3αHP binding.
  • Estradiol and 5αP resulted in significant dose-dependent increases, whereas 3αHP and 20αHP each resulted in dose-dependent decreases in total ER
  • In combination, estradiol + 5αP or 3αHP + 20αHP resulted in additive increases or decreases respectively in ER numbers.
  • The data suggest that the action of 5αP on breast cancer cells involves modulation of the MAPK signaling pathway
  • current evidence does not appear to support the notion that increased 5α-reductase activity/ expression might significantly alter androgen influences on breast tumor growth.
  • both testosterone and DHT inhibit cell growth more or less to the same extent
  • Note that 5α-reductase reaction is not reversible
  • Nathan Goodyear on 20 Feb 12
     
    Fantastic read on the effects of progesterone metabolism on tumor and cancer growth.  Tumorigenesis is not just about the hormone, hormone balance, but about the metabolism of hormones.  This is why premarin is so carcinogenic: it is primarily metabolized by the 4-OH estrone pathway.
Nathan Goodyear

The 4-Pregnene and 5α-Pregnane Progesterone Metabolites Formed in Nontumorous... - 0 views

cancerres.aacrjournals.org/...936.full

progesterone metabolism cancer risk 4-pregnene 5alpha-pregnane

shared by Nathan Goodyear on 17 Feb 12 - No Cached
  • We report here the first evidence that tumorous breast tissue exhibits elevated 5α-reductase activity, which promotes significant increases in 5α-pregnanes, especially 5αP,4 whereas the normal (nontumorous) breast tissue produces more 4-pregnenes, especially 3αHP
  • 3αHP and other 4-pregnenes inhibit, whereas 5αP and other 5α-pregnanes stimulate, breast cell proliferation and detachment
  • it is evident that breast tissue can convert progesterone into two classes of metabolites: the δ-4-pregnenes (which retain the C4–5 double bond), and the 5α-reduced 21-carbon steroids (5α-pregnanes)
  • ...12 more annotations...
  • irreversible action of 5α-reductase
  • in normal (nontumorous) breast tissue, the 4-pregnene metabolites of progesterone greatly exceeded the 5α-pregnanes, whereas in tumorous tissue, 5α-pregnanes exceeded 4-pregnenes.
  • These differences in 5α-pregnane and 4-pregnene amounts were largely attributable to differences in 5αP and 3αHP production in tumorous and nontumorous tissues
  • the metabolic activities were in general similar, regardless of the age and ER state of the patient or whether she was pre- or postmenopausal.
  • These findings suggest greatly elevated 5α-reductase activity in tumorous, as compared with nontumorous, breast tissue.
  • progesterone metabolites that retain the C-4 double bond (i.e., the 4-pregnenes) exert an antiproliferative effect in the three cell lines that were tested, whereas the 5α-pregnanes stimulate breast cell line proliferation.
  • the degree of mitogenicity would be determined by the ratio of 5α-pregnanes:4-pregnenes. Tissues with a high 4-pregnene:5α-pregnane ratio would maintain a higher degree of normalcy, whereas those with a high 5α-pregnane:4-pregnene ratio would tend toward tumorigenicity
  • The observations that progesterone metabolites affect both ER-positive and ER-negative cells as well as tumorigenic (MCF-7) and nontumorigenic (MCF-10A) cells strengthen the argument that these factors may be endocrinologically relevant for all forms of breast cancer.
  • progesterone metabolites as the active endocrine/paracrine/autocrine factors
  • Estrogen-based therapies elicit responses in only one-third of all breast cancer patients, and most of these show relapse.
  • the metabolic activities were in general similar, regardless of the age and ER state of the patient or whether she was pre- or postmenopausal.
    • Nathan Goodyear
      Nathan Goodyear on 27 Jan 14
       
      Interesting that the effect of progesterone metabolites were found to be independent from ER status, age, and pre/post menopause
  • Nathan Goodyear on 17 Feb 12
     
    Different progesterone metabolites shown to have different tumor effects.  Implications are that, just as estrogen metabolism effects cancer risk, so does progesterone metabolism.
Nathan Goodyear

Ki-67 is a prognostic parameter in breast cancer patients: results of a large populatio... - 0 views

www.ncbi.nlm.nih.gov/...PMC3669503

ki-67 cancer breast cancer

shared by Nathan Goodyear on 06 Sep 18 - No Cached
  • A wide range of techniques is available to assess tumor cell proliferation such as calculating mitotic figures in stained tissue segments, flow cytometric analysis to determine the proportion of cells being in the S phase of the cell cycle, examination of thymidine-labeling index, proliferating cell nuclear antigen (PCNA), or cyclins E and D
  • Ki-67 is a nuclear protein being associated with cellular proliferation and was originally identified by Gerdes et al.
  • Ki-67 nuclear antigen is expressed in certain phases of the cell cycle namely S, G1, G2, and M phases, but is nonexisting in G0
  • ...11 more annotations...
  • Ki-67 is also expressed at low levels (<3 % of cells) in ER-negative cells, but not in ER-positive cells
  • A meta-analysis involving 12,155 patients demonstrated that the Ki-67 positivity confers a higher risk of recurrence and a worse survival rate in patients with early breast cancer.
  • high levels of Ki-67 are associated with worse prognoses
  • Ki-67 was associated with worse survival rates
  • associated with proliferation
  • higher tumor stages and higher nodal status were associated with higher Ki-67 quartiles indicating that the more aggressive the tumor is the higher is the percentage of cells positively stained for Ki-67
  • Previous studies were able to demonstrate that a prognostic model, the IHC 4 score, using ER, PR, HER2, and Ki-67 provides similar prognostic information to that in the 21-gene Genomic Health recurrence score
  • ER status has been largely identified as being inversely correlated with Ki-67, with the higher rates of ER positivity shown in the lowest proliferating tumors
  • high levels of Ki-67 are associated with HER2/-neu positivity according to former studies
  • higher values of Ki-67-labeling index were associated with adverse prognostic factors
  • Ki-67-labeling index was associated with larger tumors, higher tumor grade, peritumoral vascular invasion, and HER-2 positivity
  • Nathan Goodyear on 06 Sep 18
     
     Increased disease free survival and overall survival in people with breast cancer with ki-67 <15%
Nathan Goodyear

Neoadjuvant chemotherapy induces breast cancer metastasis through a TMEM-mediated mecha... - 0 views

www.ncbi.nlm.nih.gov/...PMC5592784

Chemotherapy metastasis cancer TMEMs 'tumor microenvironment of metastasis' "chemotherapy metastasis"

shared by Nathan Goodyear on 22 Jan 19 - No Cached
  • Nathan Goodyear on 22 Jan 19
     
    Study looked at tumor microenvironment of metastasis structures (TMEMs) involved in metastasis. It has also been shown that taxane-based chemotherapies promote tumor regrowth by inducing angiogenesis. In this study, the tumor growth was slowed with taxanes chemotherapies, but it increased TMEMs and thus metastatic potential.
Nathan Goodyear

Targeting tumor-infiltrating macrophages decreases tumor-initiating cells, relieves imm... - 0 views

www.ncbi.nlm.nih.gov/...PMC3563931

TAMS chemotherapy Tumor associate macrophages cancer

shared by Nathan Goodyear on 16 Feb 21 - No Cached
  • Nathan Goodyear on 16 Feb 21
     
    Chemotherapy increases TAMs in the primary tumors. These TAMs suppresses the anti-cancer cytotoxicity of T cells. The authors here describe both TAMs and TIMs. TAMs are the M1/M2 most often discussed. M2 TAMs increase Tumor Infiltrating Macrophages (TIMs) which increase local immunosuppression and chemotherapy resistance.
spineneuro

Oman Patient Underwent Successful Brain Tumor Surgery in India - Spine and Neuro Hospit... - 0 views

spineandneurosurgeryhospitalindia.wordpress.com/...l-brain-tumor-surgery-in-india

Dr. Sandeep Dr. Sandeep Vaishya India affordable brain tumor surgery cost in India Contact Dr. Sandeep Vaishya Fortis Hospital Delhi Top Hospitals for Brain Tumor India Brain Tumor Surgery in India

shared by spineneuro on 08 Oct 21 - No Cached
  • spineneuro on 08 Oct 21
     
    Bahir said "I came to India for my mother's treatment, and I will never regret choosing spine and neurosurgery service India. They have been with us from our visa, to the airport, to hotels they helped us get in contact with Dr. Sandeep Vaishya Fortis Hospital Delhi, they also helped us get affordable brain tumor surgery cost in India. Email: dr.sandeepvaishya@neurospinehospital.com Phone No.: +91-9325887033
spineneuro

Glimpses into the Future: Innovations in Brain Tumor Surgery and Beyond - SpineandNeuro... - 0 views

tealfeed.com/ions-brain-tumor-surgery-m7gdy

top 10 brain tumor surgeons in the world brain tumor Surgeons Brain Tumor

shared by spineneuro on 07 Sep 23 - No Cached
  • spineneuro on 07 Sep 23
     
    Opting for the best top 10 brain tumor surgeons in the world ensures minimal complications post-treatment and reduces stress for both the patient and their family. 
spineneuro

India's Best Brain Tumor Surgeons Will Increase Your Life Span - 0 views

www.briefingwire.com/...s-will-increase-your-life-span

Brain tumor surgery India's Best Brain Tumor Surgeons low cost brain tumor surgery.

shared by spineneuro on 03 Aug 22 - No Cached
  • spineneuro on 03 Aug 22
     
    Brain tumor surgery is extraordinarily affordable and when compared to the developed countries come out to be extraordinarily low cost, which is nearly one-third of the cost in the evaluation of the US & UK
spineneuro

India's Top Brain Tumor Surgeons: Heroes of Hope and Healing - 0 views

steemit.com/...ons-heroes-of-hope-and-healing

Brain Tumor Brain Tumor surgery Brain Tumor surgery cost

shared by spineneuro on 15 Nov 23 - No Cached
  • spineneuro on 15 Nov 23
     
    India stands out as the preferred destination for patients from across the globe, thanks to the country's highly knowledgeable and skilled brain tumor surgeons India who offer advanced and innovative treatment options.
spineneuro

A Price You Can Afford: Accessing World-Class Brain Tumor Surgery in India - 0 views

www.briefingwire.com/...s-brain-tumor-surgery-in-india

hospitals for brain tumors India brain tumors brain tumors surgery cost

shared by spineneuro on 09 Apr 24 - No Cached
  • spineneuro on 09 Apr 24
     
    Top hospitals for brain tumors India have earned accreditation from esteemed healthcare monitoring organizations such as NABL, NABH, and JCI, owing to their exceptional infrastructure, cutting-edge clinical facilities, and excellent treatments.
Nathan Goodyear

Energy Intake and Prostate Tumor Growth, Angiogenesis, and Vascular Endothelial Growth ... - 0 views

jnci.oxfordjournals.org/...512.long

prostate cancer tumor angiogenesis calorie restriction

shared by Nathan Goodyear on 02 Jul 13 - No Cached
  • Nathan Goodyear on 02 Jul 13
     
    Granted, this is prostate tumor rat model.  But, a calorie restriction of 20-40% resulted in reduced tumor growth through inhibition of angiogenesis.
Nathan Goodyear

Estrogen Regulates Tumor Growth Through a Nonclassical Pathway that Includes the Transc... - 0 views

stke.sciencemag.org/...ra22

prostate cancer ER-beta ER estrogen receptor receptors tumor suppression factor KLF5

shared by Nathan Goodyear on 06 Oct 12 - No Cached
  • Nathan Goodyear on 06 Oct 12
     
    ER-beta inhibits prostate tumor growth through the tumor suppression factor KLF5.
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