Skip to main content

Home/ Dr. Goodyear/ Group items tagged tyrosine

Rss Feed Group items tagged

Nathan Goodyear

Communication between genomic and non-genomic signaling events coordinate steroid hormo... - 0 views

  • steroid hormones typically interact with their cognate receptor in the cytoplasm for AR, glucocorticoid receptor (GR) and PR, but may also bind receptor in the nucleus as appears to often be the case for ERα and ERβ
  • This ligand binding results in a conformational change in the cytoplasmic NRs that leads to the dissociation of HSPs, translocation of the ligand-bound receptor to the nucleus
  • In the nucleus, the ligand-bound receptor dimerizes and then binds to DNA at specific HREs to regulate gene transcription
  • ...25 more annotations...
  • some steroid hormone-induced nuclear events can occur in minutes
  • the genomic effects of steroid hormones take longer, with changes in gene expression occurring on the timescale of hours
  • Classical steroid hormone signaling occurs when hormone binds nuclear receptors (NR) in the cytoplasm, setting off a chain of genomic events that results in, among other changes, dimerization and translocation to the nucleus where the ligand-bound receptor forms a complex with coregulators to modulate gene transcription through direct interactions with a hormone response element (HRE)
  • NRs have been found at the plasma membrane of cells, where they can propagate signal transduction often through kinase pathways
  • Membrane-localized ER, PR and AR have been reported to modulate the activity of MAPK/ERK, phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt), nitric oxide (NO), PKC, calcium flux and increase inositol triphosphate (IP3) levels to promote cell processes including autophagy, proliferation, apoptosis, survival, differentiation, and vasodilation
  • ERα36, a 36kDa truncated form of ERα that lacks the transcriptional activation domains of the full-length protein. Membrane-localized ERα36 can activate pathways including protein kinase C (PKC) and/or mitogen activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) to promote the progression of various cancers
  • G protein-coupled receptor 30 (GPR30), also referred to as G protein-coupled estrogen receptor (GPER), is a membrane-localized receptor that has been observed to respond to estrogen to activate rapid signaling
  • hormone-responsive G protein coupled receptor is Zip9, which androgens can activate
  • GPRC6A is another G protein-coupled membrane receptor that is responsive to androgen
  • androgen-mediated non-genomic signaling through this GPCR can modulate male fertility, hormone secretion and prostate cancer progression
  • non-NR proteins located at the cell surface can bind to steroid hormones and respond by eliciting rapid signaling events
  • Estrogens have been shown to induce rapid (i.e. seconds) calcium flux via membrane-localized ER (mER)
  • ER-calcium dynamics lead to activation of kinase pathways such as MAPK/ERK which can result in cellular effects like migration and proliferation
  • 17β-estradiol (E2) has been reported to promote angiogenesis through the activation of GPER
  • Membrane NRs may also mediate rapid signaling through crosstalk with growth factor receptors (GFR)
  • A similar crosstalk occurs between the receptor tyrosine kinase insulin-related growth factor-1 receptor (IGF-IR) and ERα. Not only does IGF-IR activate ERα, but inhibition of IGF-IR downregulates estrogen-mediated ERα activity, suggesting that IGF-IR is essential for maximal ERα signaling
    • Nathan Goodyear
       
      This is a bombshell that shatters the current right brain approach to ER. It completely shatters the concept of eat sugar, whatever you want, with cancer treatment in ER+ or hormonally responsive cancer!
  • Further, ER activates IGF-IR pathways including MAPK
  • GPER is involved in the transactivation of the EGFR independent of classical ER
  • tight interconnection between genomic and non-genomic effects of NRs.
  • non-genomic pathways can also lead to genomic effects
  • androgen-bound AR associates with the kinase Src at the plasma membrane, activating Src which then leads to a signaling cascade through MAPK/ERK
  • However, Src can also increase the expression of AR target genes by the ligand-independent transactivation of AR
  • extranuclear steroid hormone actions can potentially reprogram nuclear NR events
  • estrogen modulated the expression of several genes including endothelial nitric oxide synthase (eNOS) via rapid signaling pathways
  • epigenetic changes can then mediate genomic events in uterine tissue and breast cancer cells
Nathan Goodyear

Insulin Resistance Induced by Hyperinsulinemia Coincides with a Persistent Alteration a... - 0 views

  •  
    Hyperinsulinemia causes insulin resistance through an attempt to downregulates over signaling.
Nathan Goodyear

Phase I clinical trial of the flavonoid quercetin: pharmacokinetics and evidence for in... - 0 views

  •  
    Great phase 1 pharmacokinetic study on Quercetin dosing.
Nathan Goodyear

Repurposing Drugs in Oncology (ReDO)-chloroquine and hydroxychloroquine as anti-cancer ... - 0 views

  • HCQ, doses for long-term use range between 200 and 400 mg per day.
  • Short-term administration of CQ or HCQ rarely causes severe side effects
  • Short-term administration of CQ or HCQ rarely causes severe side effects
  • ...24 more annotations...
  • bone marrow suppression
  • cardiomyopathy
  • irreversible retinal toxicity
  • hypoglycaemia
  • daily doses up to 400 mg of HCQ or 250 mg CQ for several years are considered to carry an acceptable risk for CQ-induced retinopathies, with the exception of individuals of short stature
  • chronic CQ or HCQ therapy be monitored through regular ophthalmic examinations (3–6 month intervals), full blood counts and blood glucose level checks
  • long-term HCQ exposure, skeletal muscle function and tendon reflexes should be monitored for weakness
  • both CQ and HCQ, specific caution is advised in patients suffering from impaired hepatic function (especially when associated with cirrhosis), porphyria, renal disease, epilepsy, psoriasis, glucose-6-phosphate dehydrogenase deficiency and known hypersensitivity to 4-aminoquinoline compounds
  • CQ and HCQ can effectively increase the efficacy of various anti-cancer drugs
  • CQ can prevent the entrapment of protonated chemotherapeutic drugs by buffering the extracellular tumour environment and intracellular acidic spaces
  • This study recommends an adjuvant HCQ dose of 600 mg, twice daily.
  • HCQ addition was shown to produce metabolic stress in the tumours
  • HCQ (400 mg/day)
  • important effects of CQ and HCQ on the tumour microenvironment
  • The main and most studied anti-cancer effect of CQ and HCQ is the inhibition of autophagy
  • the expression levels of TLR9 are higher in hepatocellular carcinoma, oesophageal, lung, breast, gastric and prostate cancer cells as compared with adjacent noncancerous cells, and high expression is often linked with poor prognosis
  • TLR9-mediated activation of the NF-κB signalling pathway and the associated enhanced expression of matrix metalloproteinase-2 (MMP-2), MMP-7 and cyclo-oxygenase 2 mRNA
  • HCQ can activate caspase-3 and modulate the Bcl-2/Bax ratio inducing apoptosis in CLL, B-cell CLL and glioblastoma cells
  • In triple-negative breast cancer, CQ was shown to eliminate cancer stem cells through reduction of the expression of Janus-activated kinase 2 and DNA methyl transferase 1 [106] or through induction of mitochondrial dysfunction, subsequently causing oxidative DNA damage and impaired repair of double-stranded DNA breaks
  • CQ or HCQ would be considered for use in combination with immunomodulation anti-cancer therapies
  • Therapies used in combination with CQ or HCQ include chemotherapeutic drugs, tyrosine kinase inhibitors, various monoclonal antibodies, hormone therapies and radiotherapy
  • Most studies hypothesise that CQ and HCQ could increase the efficacy of other anti-cancer drugs by blocking pro-survival autophagy.
  • daily doses between 400 and 1200 mg for HCQ are safe and well tolerated, but two studies identified 600-mg HCQ daily as the MTD
  • HCQ is often administered twice daily to limit plasma fluctuations and toxicity
‹ Previous 21 - 33 of 33
Showing 20 items per page