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Archive for the ‘Methylation’ Category

Larry H. Bernstein, MD, FCAP, reviewer and curator

http://pharmaceuticalintelligence.com/2013-12-09/larryhbern/VEGF-activation-and-signaling,-lysine-methylation,-and-activation-of-receptor-tyrosine-kinase

Lysine Methylation Promotes VEGFR-2 Activation and Angiogenesis

 Edward J. Hartsough1*, Rosana D. Meyer1*, Vipul Chitalia2, Yan Jiang3, Victor E. Marquez4, Irina V. Zhdanova5, Janice Weinberg6, Catherine E. Costello3, and Nader Rahimi1{dagger}
 1 Departments of Pathology and Ophthalmology, School of Medicine, Boston University Medical Campus, Boston, MA 02118, USA.
2 Harvard-MIT Division of Health Science and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
3 Department of Biochemistry and Center for Biomedical Mass Spectrometry, School of Medicine, Boston University Medical Campus, Boston, MA 02118, USA.
4 Chemical Biology Laboratory, National Cancer Institute at Frederick, Frederick, MD 21702, USA.
5 Department of Anatomy and Neurobiology, Boston University Medical Campus, Boston, MA 02118, USA.
6 School of Public Health, Boston University Medical Campus, Boston, MA 02118, USA.
Activation of vascular endothelial growth factor receptor-2 (VEGFR-2), an endothelial cell receptor tyrosine kinase,
  • promotes tumor angiogenesis and ocular neovascularization.
We report the methylation of VEGFR-2 at multiple Lys and Arg residues, including Lys1041,
  • a residue that is proximal to the activation loop of the kinase domain.
Methylation of VEGFR-2 was
  • independent of ligand binding and
  • was not regulated by ligand stimulation.
Methylation of Lys1041 enhanced tyrosine phosphorylation and kinase activity in response to ligands. Additionally, interfering with the methylation of VEGFR-2 by pharmacological inhibition or by site-directed mutagenesis revealed that
  • methylation of Lys1041 was required for VEGFR-2–mediated angiogenesis
    • in zebrafish and
    • tumor growth in mice.
We propose that methylation of Lys1041 promotes the activation of VEGFR-2 and that
  • similar posttranslational modification could also regulate the activity of other receptor tyrosine kinases.
{dagger} Corresponding author. E-mail: nrahimi@bu.edu
Citation: E. J. Hartsough, R. D. Meyer, V. Chitalia, Y. Jiang, V. E. Marquez, I. V. Zhdanova, J. Weinberg, C. E. Costello, N. Rahimi, Lysine Methylation Promotes VEGFR-2 Activation and Angiogenesis. Sci. Signal. 6, ra104 (2013).

Phosphoproteomic Analysis Implicates the mTORC2-FoxO1 Axis in VEGF Signaling and Feedback Activation of Receptor Tyrosine Kinases

Guanglei Zhuang, Kebing Yu, Zhaoshi Jiang, Alicia Chung, Jenny Yao, Connie Ha, Karen Toy, Robert Soriano, Benjamin Haley, Elizabeth Blackwood, Deepak Sampath, Carlos Bais, Jennie R. Lill, and Napoleone Ferrara (16 April 2013){dagger}
Sci. Signal. 16 April 2013;  6 (271), ra25.    http://dx.doi.org/10.1126/scisignal.2003572
Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
* These authors contributed equally to this work.{dagger}
{dagger} Present address: Department of Pathology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA.
The vascular endothelial growth factor (VEGF) signaling pathway plays a pivotal role in normal development and
  • also represents a major therapeutic target for tumors and intraocular neovascular disorders.
The VEGF receptor tyrosine kinases promote angiogenesis by phosphorylating downstream proteins in endothelial cells. We applied a large-scale proteomic approach to define
  1. the VEGF-regulated phosphoproteome and
  2. its temporal dynamics in human umbilical vein endothelial cells and then
  3. used siRNA (small interfering RNA) screens to investigate the function of a subset of these phosphorylated proteins in VEGF responses.
The PI3K (phosphatidylinositol 3-kinase)–mTORC2 (mammalian target of rapamycin complex 2) axis emerged as central
  1. in activating VEGF-regulated phosphorylation and
  2. increasing endothelial cell viability
    • by suppressing the activity of the transcription factor FoxO1 (forkhead box protein O1),
    • an effect that limited cellular apoptosis and feedback activation of receptor tyrosine kinases.
This FoxO1-mediated feedback loop not only reduced the effectiveness of mTOR inhibitors at decreasing protein phosphorylation and cell survival
  • but also rendered cells more susceptible to PI3K inhibition.
Collectively, our study provides a global and dynamic view of VEGF-regulated phosphorylation events and
  • implicates the mTORC2-FoxO1 axis in VEGF receptor signaling and
  • reprogramming of receptor tyrosine kinases in human endothelial cells.
{ddagger} Corresponding author. E-mail: nferrara@ucsd.edu
Citation: G. Zhuang, K. Yu, Z. Jiang, A. Chung, J. Yao, C. Ha, K. Toy, R. Soriano, B. Haley, E. Blackwood, D. Sampath, C. Bais, J. R. Lill, N. Ferrara, Phosphoproteomic Analysis Implicates the mTORC2-FoxO1 Axis in VEGF Signaling and Feedback Activation of Receptor Tyrosine Kinases. Sci. Signal. 6, ra25 (2013).

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Larry H Bernstein, MD, FCAP, Reporter and Curator

http://pharmaceuticalintelligence.com/2013-12-07/larryhbern/Epigenomics and Companion Diagnostics

The development of epigenomics has reached a new stage.  Therapeutics has long been hampered from making important inroads to personalized medicine by the inability to differentiate patients with the same disorder having subvariants that react favorably and others that fail a treatment with an expected response.  These developments in diagnostics have been needed and rely specifically on laboratory-based diagnostics.  As these developments unfold, it will ba a very significant challenge to the clinical laboratory industry in the education and staffing of technologists.  This is already at a time that laboratory post-bacchalaureate education and staffing and accreditation of laboratories has not yet caught up to the need.

Epigenetics: Diagnostic and Therapeutic Applications

DDD Dec07, 2013

RiboMed and NuvOx Pharma to Collaborate on Brain Cancer Drug and Companion Diagnostic Test

RiboMed Biotechnologies, Inc. and NuvOx Pharma today jointly announced that they have entered into a collaborative agreement that will utilize RiboMed’s epigenetic biomarker test, GliomaSTRAT™, to characterize tumors from brain cancer patients and correlate response to NuvOx’s new drug, NVX-108 in the treatment of Glioblastoma multiforme (GBM).
“Our goal at RiboMed is to develop Companion Diagnostic tests that will help to prevent the treatment of patients with drugs to which they will not respond,” said Dr. Michelle Hanna, CEO and Scientific Director at RiboMed.
Carlsbad, CA and Tucson, AZ (PRWEB) December 05, 2013
RiboMed Biotechnologies, Inc. and NuvOx Pharma today jointly announced that they have entered into a collaborative agreement that will utilize
  • RiboMed’s epigenetic biomarker test, GliomaSTRAT™, to characterize tumors from brain cancer patients and
  • correlate response to NuvOx’s new drug, NVX-108 in the treatment of Glioblastoma multiforme (GBM).
NVX-108 is an intravenously delivered drug that, in animal models, increases the concentration of oxygen in tumors and consequently increases tumor sensitivity to radiation treatment. In animals implanted with human tumors which are resistant to radiation because they are low in oxygen, NVX-108 increased tumor oxygen levels by 400% and prolonged survival of the animals with tumors that were treated with radiation.
“The Phase 1B will begin early in Q1 2014 to evaluate the safety and efficacy of NVX-108 in combination with the current standard of care. We anticipate that incorporating RiboMed’s GliomaSTRAT into our Phase 1B clinical protocol will improve our ability to further stratify the resulting clinical data to ascertain optimal dosing and corresponding benefit of NVX-108 to patients with this disease, for which there are no good therapies,” noted NuvOx’s Chief Business Officer David Wilson.
The standard of care for patients with Glioblastoma brain cancer is surgery, followed by a 6-week course of radiation therapy and treatment with temozolomide. The patient’s response to treatment depends upon their tumor’s sensitivity to both the radiation and to the drug. RiboMed’s GliomaSTRAT is a DNA methylation based test that stratifies brain tumors into 4 groups, by
  • both grade (low grade vs high grade) and
  • response to certain chemotherapeutic drugs, including temozolomide (Temodar®).
“Our goal at RiboMed is to develop Companion Diagnostic tests that will help to prevent the treatment of patients with drugs to which they will not respond,” said Dr. Michelle Hanna, CEO and Scientific Director at RiboMed. “Given the differential response of high grade and low grade tumors to radiation, this stratification step could identify the patients that are most likely to benefit from treatment with NVX-108.”
RiboMed’s technology for epigenetic testing provides up to 100-fold greater sensitivity than competing methods. Tests utilize RiboMed’s bisulfite-free, methylated DNA enrichment process, MethylMagnet®, and their proprietary biomarker detection technology, Abscription®, which together in MethylMeter® provide superior sensitivity and specificity for the detection of DNA methylation in clinical samples. MethylMeter®
  • allows quantitative analysis of DNA methylation,
  • even with small samples containing damaged DNA, including formalin fixed paraffin embedded (FFPE) tissues.

About RiboMed

RiboMed Biotechnologies, Inc. (http://www.ribomed.com) is a College of American Pathology (CAP) accredited and CLIA-certified molecular diagnostic clinical laboratory and Contract Research Organization. The RiboMed Clinical Services Laboratory offers DNA methylation based tests for cancer and drug response related biomarkers to physicians and for use in clinical trials, as well as development services to research institutions and Pharma. Research Use Only (RUO) kits, reagents, and technology licensing are also available. More information can be requested at info(at)  http://ribomed.com.

About NuvOx

NuvOx was founded in 2008, after in-licensing NVX-108 for therapeutic applications, after it was demonstrated to be safe and effective as an ultrasound contrast imaging agent in more than 2200 patients. Serving as an oxygen therapeutic, previously demonstrated to be safe in humans, testing in animal models has demonstrated potential therapeutic application for sensitization to radiation treatment in many cancers, the mitigation of brain damage from stroke, heart damage from heart attack and general tissue destruction resulting from hemorrhagic shock. For additional information, please contact David Wilson at dwilson(at)nuvoxpharma(dot)com or call +1 (520) 624-6688 x1004.  http://www.nuvoxpharma.com.

Disclosure Regarding Forward-Looking Statements

Except for historical information contained herein, the matters set forth in this press release, including statements regarding the Company’s expectations, are forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to risks and uncertainties that may cause actual results to differ materially, including the risks and uncertainties associated with market demand for and acceptance and use of technology and tests such as the GliomaSTRAT test and NVX-108, separately or in combination, reliance upon the collaborative efforts of other parties including without limitation NuvOx, RiboMed or third parties obtaining or maintaining regulatory approvals that impact the Company’s business, government regulation particularly with respect to diagnostic products and laboratory developed tests, the Company’s ability to develop and commercialize technologies and products, particularly new technologies such as laboratory developed tests and genetic analysis platforms, the Company’s financial position, the Company’s ability to manage its existing cash resources or raise additional cash resources, competition, intellectual property protection and intellectual property rights of others, litigation involving the Company, and other risks. These forward-looking statements are based on current information that may change and you are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. All forward-looking statements are qualified in their entirety by this cautionary statement, and the Company undertakes no obligation to revise or update any forward-looking statement to reflect events or circumstances after the issuance of this press release.
SOURCE: RiboMed Biotechnologies, Inc. and NuvOx Pharma, LLC

Epigenomics FDA Advisory Panel Date to Review Epi proColon®

Jordan deVos Marketing Specialist at Epigenomics AG

Epigenomics has announced that the Company was informed by the U.S. Food and Drug Administration (FDA) via the premarket approval (PMA) review process for Epi proColon® that the Meeting of the Molecular and Clinical Genetics Panel of the Medical Devices Advisory Committee has been tentatively scheduled for Tuesday, March 25th, 2014. Epi proColon® is Epigenomics’ blood-based screening test for colorectal cancer.
Epigenomics AG Announces FDA Advisory Committee Meeting to Review Epi… epigenomics.com
Berlin, Germany, and U.S.A., November 27, 2013 – Epigenomics AG (Frankfurt Prime Standard: ECX, OTC: EPGNY), the German-American cancer molecular diagnostics company, today announced that the Company was informed by the U.S. Food and Drug…

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Warburg Effect Revisited

Reporter: Larry H. Bernstein, MD, FCAP

We have previously covered the Warburg Effect, and there has been a number of comments about the chicken or the egg!  There is an underlying factor that makes it difficult to comprehend that the initiation of cancer is mutation driven, although we are clear that smoking and a number of environmental factors are instigators of the change.  The main problem that I have referred to is the chemical, thermodynamic, and evolutionary state of our existence.  I strongly refer to the work of Ilya Prigogene.  There is a progressive series of changes over time, and it is not possible to determine the initial state.  Consequently, a progressive series of adaptations progresses, involving gene expression, non-genetic changes, and metabolic equilibrium that is maintained, but becomes non-adaptive.

Previous discussions at LPI are:

AMPK Is a Negative Regulator of the Warburg Effect and Suppresses Tumor Growth In Vivo
Reporter-Curator: Stephen J. Williams, Ph.D.
http://pharmaceuticalintelligence.com/2013/03/12/ampk-is-a-negative-regulator-of-the-warburg-effect-and-suppresses-tumor-growth-in-vivo/

Is the Warburg Effect the Cause or the Effect of Cancer: A 21st Century View?
Author: Larry H. Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2012/10/17/is-the-warburg-effect-the-cause-or-the-effect-of-cancer-a-21st-century-view/

Otto Warburg, A Giant of Modern Cellular Biology
Reporter: Larry H Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2012/11/02/otto-warburg-a-giant-of-modern-cellular-biology/

Targeting Mitochondrial-bound Hexokinase for Cancer Therapy
Author: Ziv Raviv, PhD
http://pharmaceuticalintelligence.com/2013/04/06/targeting-mito…cancer-therapy

Portrait of a great scientist and mentor: Nathan Oram Kaplan
Writer and Curator, Larry H Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2013/01/26/portrait-of-a-great-scientist-and-mentor-nathan-oram-kaplan/

Quantum Biology And Computational Medicine
Author and Curator, Larry H Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2013/04/03/quantum-biology-and-computational-medicine/

Ubiquitin-Proteosome pathway, Autophagy, the Mitochondrion, Proteolysis and Cell Apoptosis: Part III
Curator: Larry H Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2013/02/14/ubiquinin-proteosome-pathway-autophagy-the-mitochondrion-proteolysis-and-cell-apoptosis-reconsidered/

Differentiation Therapy – Epigenetics Tackles Solid Tumors
Author-Writer: Stephen J. Williams, Ph.D.
http://pharmaceuticalintelligence.com/2013/01/03/differentiation-therapy-epigenetics-tackles-solid-tumors/

Prostate Cancer Cells: Histone Deacetylase Inhibitors Induce Epithelial-to-Mesenchymal Transition
Reporter-Curator: Stephen J. Williams, Ph.D.
http://pharmaceuticalintelligence.com/2012/11/30/histone-deacetylase-inhibitors-induce-epithelial-to-mesenchymal-transition-in-prostate-cancer-cells/

Mitochondrial Damage and Repair under Oxidative Stress
Curator: Larry H Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2012/10/28/mitochondrial-damage-and-repair-under-oxidative-stress/

Mitochondria: Origin from oxygen free environment, role in aerobic glycolysis, metabolic adaptation
Curator: Larry H Bernsatein, MD, FCAP
http://pharmaceuticalintelligence.com/2012/09/26/mitochondria-origin-from-oxygen-free-environment-role-in-aerobic-glycolysis-metabolic-adaptation/

Nitric Oxide has a ubiquitous role in the regulation of glycolysis -with a concomitant influence on mitochondrial function
Curator, Larry H. Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2012/09/16/nitric-oxide-has-a-ubiquitous-role-in-the-regulation-of-glycolysis-with-a-concomitant-influence-on-mitochondrial-function/

Potential Drug Target: Glucolysis Regulation – Oxidative stress-responsive microRNA-320
Reporter: Aviva Lev-Ari, PhD, RN
http://pharmaceuticalintelligence.com/2012/07/25/potential-drug-target-glucolysis-regulation-oxidative-stress-responsive-microrna-320/

Expanding the Genetic Alphabet and Linking the Genome to the Metabolome
Reporter& Curator: Larry Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2012/09/24/expanding-the-genetic-alphabet-and-linking-the-genome-to-the-metabolome/

What can we expect of tumor therapeutic response?
Author: Larry H. Bernstein, MD, FCAP
http://pharmaceuticalintelligence.com/2012/12/05/what-can-we-expect-of-tumor-therapeutic-response/

A Second Look at the Transthyretin Nutrition Inflammatory Conundrum
Larry H. Bernstein, MD, FACP
http://pharmaceuticalintelligence.com/2012/12/03/a-second-look-at-the-transthyretin-nutrition-inflammatory-conundrum/

Radoslav Bozov
Date: 3/26/2013
Subject: RE: comment
The process of genomic evolution cannot be revealed throughout comparative genomics as structural data representation does not illuminate either the integral path of particles-light interference, as Richard Feynman suggests, in stable forms of matter such as interference/entanglement of the nature of particles/strings/waves to first approximation as I have claimed. Towards the compressibility principle realization, I have claimed that DNA would be entropic- favorable stable state going towards absolute ZERO temp in the space defined itself. In other words themodynamics measurement in subnano discrete space would go negative towards negativity. DNA is sort of like a cold melting/growing crystal, quite stable as it appears not due to hydrogen bonding , but due to interference of C-N-O. That force is contradicted via proteins onto which we now know large amount of negative quantum redox state carbon attaches. Chemistry is just a language as it is math following certain rules based on observation. Most stable states are most observed ones. The more locally one attempts to observe, the more hidden variables would emerge as a consequence of discrete energy spaces opposing continuity of matter/time. Still, stability emerges out of non stability states. And if life was in absolute stability, there will be neither feelings nor freedom. What is feelings and freedom is a far reaching philosophical question with sets of implications, to one may be a driving car, to another riding a horse or a bicycle etc cetera or simply seeing the unobservable …No wonder genome size differs among organisms and even tissue types as an outcome of carbon capacity.

 PIM2 phosphorylates PKM2 and promotes Glycolysis in Cancer Cells

Yu Z, Huang L, Zhang T, Yang F, Xie L, Liu J, Song S, Miao P, Zhao L, Zhao X, Huang G.
Shanghai Jiao Tong University, China;
J Biol Chem. 2013 Oct 18. [Epub ahead of print]

  • Pyruvate kinase M2 (PKM2) is a key player in the Warburg effect of cancer cells.
  •  the mechanisms of regulating PKM2 are not fully elucidated.
  •  we identified the serine/threonine protein kinase PIM2, a known oncogene,
    • as a novel binding partner of PKM2.

The interaction between PIM2 and PKM2 was confirmed by multiple biochemical approaches in vitro and in cultured cells. Importantly, we found that

  • PIM2 could directly phosphorylate PKM2 on the Thr454 residue, resulting in
    • an increase of PKM2 protein levels.

Compared to wild-type, PKM2 with the phosphorylation-defective mutation

  • displayed a reduced effect on glycolysis, co-activating HIF-1α and β-catenin, and cell proliferation,
  • while enhanced mitochondria respiration and chemotherapeutic sensitivity of cancer cells.

These findings demonstrate that PIM2-dependent phosphorylation of PKM2 is critical for regulating the Warburg effect in cancer,

    • highlighting PIM2 as a potential therapeutic target.

KEYWORDS: Cancer, Cell proliferation, Glycolysis, Pyruvate kinase, phosphorylation
PMID: 24142698

Different mtDNA mutations modify tumor progression in dependence of the degree of respiratory complex I impairment.

Iommarini L, Kurelac I, Capristo M, Calvaruso MA, Giorgio V, Bergamini C, Ghelli A, et al.
Dipartimento di Farmacia e Biotecnologie (FABIT).
Hum Mol Genet. 2013 Nov 11. [Epub ahead of print]

Mitochondrial DNA mutations are currently investigated as modifying factors impinging on tumor growth and aggressiveness,

  • having been found in virtually all cancer types and
  • most commonly affecting genes encoding mitochondrial complex I (CI) subunits.

It is still unclear whether they exert a pro- or anti-tumorigenic effect.

We here analyzed the impact of three homoplasmic mtDNA mutations (m.3460G>A/MT-ND1, m.3571insC/MT-ND1 and m.3243A>G/MT-TL1) on osteosarcoma progression,

  • chosen since they induce different degrees of oxidative phosphorylation impairment.

In fact, the m.3460G>A/MT-ND1 mutation caused only a reduction in CI activity, whereas

  • the m.3571insC/MT-ND1 and the m.3243A>G/MT-TL1 mutations induced a severe structural and functional CI alteration.

As a consequence, this severe CI dysfunction determined an energetic defect associated with a compensatory increase in glycolytic metabolism and AMP-activated protein kinase activation.

Osteosarcoma cells carrying such marked CI impairment

  • displayed a reduced tumorigenic potential both in vitro and in vivo, when compared with cells with mild CI dysfunction, suggesting that
  • mtDNA mutations may display diverse impact on tumorigenic potential depending on
  • the type and severity of the resulting oxidative phosphorylation dysfunction.

The modulation of tumor growth was independent from reactive oxygen species production but correlated with

  • hypoxia-inducible factor 1α stabilization, indicating that
  • structural and functional integrity of CI and oxidative phosphorylation are required for hypoxic adaptation and tumor progression.

PMID: 24163135 [PubMed – as supplied by publisher]

 Systematic Identification of Molecular Subtype-Selective Vulnerabilities in Non-Small-Cell Lung Cancer

Hyun Seok Kim, Saurabh Mendiratta, Jiyeon Kim, Chad Victor Pecot, Jill E. Larsen, et al.
Cell, 24 Oct 2013; 155 (3): 552-566, doi:10.1016/j.cell.2013.09.041
Systematic isolation of context-dependent vulnerabilities in NSCLC

Highlights

  1. NLRP3 mutations drive addiction to FLIP expression
  2. Lysosome maturation is a metabolic bottleneck for KRAS/LKB1 tumors
  3. Selective sensitivity to an indolotriazine discriminates a NSCLC expression subtype

NSCLC expression subtype

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