Skip to main content

Home/ Dr. Goodyear/ Group items tagged hypermethylation

Rss Feed Group items tagged

Nathan Goodyear

DNA methylation in cancer: too much, but also too little - 0 views

  •  
    hypermethylation and hypomethylation shown to play roles in carcinogenesis.
Nathan Goodyear

DNA methylation and cancer. - PubMed - NCBI - 0 views

  •  
    hyper and hypo methylation known to be associated with carcinogenesis.  One carcinogenic potential of hypermethylation is through suppression of tumor suppression genes.
Nathan Goodyear

Curcumin Down-Regulates DNA Methyltransferase 1 and Plays an Anti-Leukemic Role in Acut... - 0 views

  • In a variety of solid tumors and blood cancers, aberrant hypermethylation of CpG-rich regions (>55% CG content, 0.5-4 kb in length, the so-called “CpG islands”) in the promoters of tumor suppressor genes (TSGs) results in their transcriptional silencing
  • These agents have been reported to suppress tumor growth by reversing aberrantly hypermethylation in the promoters of inactivated TSGs (e.g. p15INK4B), allowing re-expression of TSGs, thereby restoring normal cell cycle regulation, proliferation, apoptosis, and differentiation
  • groups have reported that curcumin acts as a scavenger of free radicals [13], an inhibitor of NF-κB nuclear translocation [14], and a modulator of histone deacetylase (HDAC) and histone acetyltransferase (HAT)
  • ...9 more annotations...
  • In this study, we found that curcumin down-regulated DNMT1 expression in AML cells. This occurred, at least in part, through down-modulation of two positive regulators of DNMT1: Sp1 and the NF-κB component, p65. We also found that curcumin-mediated down-regulation of DNMT1 was associated with reactivation of TSGs and tumor suppression, both in vivo and in vitro.
  • curcumin may selectively downregulate DNMT1 expression in tumor cells, but not in normal cells
  • DNMT1 expression is positively regulated by Sp1 and the NF-κB signaling component
  • indicating that curcumin may have significant anti-tumor activity in AML
  • We found that, compared to the vehicle control, curcumin treatment reduced tumor weight by 70%
  • Surprisingly, although curcumin significantly inhibited tumor growth in these mice, we were unable to find any obvious toxicity associated with curcumin treatment
  • Consistent with our observations regarding curcumin’s ability to inhibit tumor growth in vivo (Figure 4) and down-regulate DNMT1 expression in vitro and ex vivo (Figure 1), we found that decreased levels of DNMT1 protein and mRNA were expressed by tumor cells isolated from curcumin-treated mice
  • we identified curcumin as a substance which acts as an inhibitor of DNA methyltransferase enzymatic activity and induces significant global DNA hypomethylation in AML cells
  • In this study, we first demonstrated that curcumin decreases DNMT1 mRNA and protein expression levels, most likely through inhibiting expression of positive regulators of DNMT1, such as Sp1 and the p65 component of NF-κB component, and/or altering their ability to bind to the promoter region of DNMT1
  •  
    Curcumin beneficial in AML
Nathan Goodyear

Hit-and-run epigenetic editing prevents senescence entry in primary breast cells from h... - 0 views

  •  
    Epigenetics is no longer something to observe, but is now something to seek to modify for therapeutic purposes.  Study targeted CPG islands for hypermethylation in primary breast cancer cells to arrest cell cycle and stop senescence escape.
Nathan Goodyear

Genomic agonism and phenotypic antagonism between estrogen and progesterone receptors i... - 0 views

  • The presence and activity of PR significantly affect the prognostic value of ER.
  • The observed loss of PR protein expression in a subset of ER+/PR+ breast cancers, because of hypermethylation or deletion of the PR gene locus, results in the loss of ER prognostic value
  • These findings emphasize the clinical value of assessing both PR and ER expression in breast cancer samples
  • ...7 more annotations...
  • PR is an essential modulator of ER-regulated genes but also that it significantly contributes to the prognostic value of ER in ER+/PR+ breast cancers
  • PR-regulated genes have independent prognostic value, and the presence of PR correlates with favorable clinicopathological outcomes
  • this study demonstrates that progestin-activated PR redirects ER chromatin binding and functions as a genomic estrogen agonist and as a phenotypic estrogen antagonist in ER+/PR+ breast cancer cells and human tumors
  • Approximately 80% of ER+ breast cancers are also positive for PR,
  • In isolation, both hormones activate or inhibit cellular processes in similar directions, although the magnitude of these effects is less for progestin alone than for estrogen alone
  • PR-mediated antagonism of estrogenic phenotypes is well documented
  • joint activation of ER and PR antagonized ER-regulated oncogenic processes
  •  
    WOW!!  study finds that progesterone through PR activity antagonizes ER protein expression by the cell.  This has huge implications in breast cancer and possible prostate cancer.  But then again, women don't need progesterone; only estrogen.  The presence of PR correlates with improved clinicopathological outcomes.  The authors do seem to get confused about progesterone and progestins.  They are not one in the same.
Nathan Goodyear

CpG hypermethylation of the promoter region inactivates the estrogen receptor... - 0 views

  •  
    ER beta expression that is lost in prostate carcinogenesis occurs via methylation at the ER beta gene promoter sites 19CpG.  What is really interesting is that ER beta expression was present in all of the samples with BPH, but was absent in 83% of the prostate cancer samples.
1 - 6 of 6
Showing 20 items per page