A once-a-month electronic newsletter of basic, preclinical and translational
research news from the Johns Hopkins School of Medicine. Please forward
freely. Browse back issues of the e-Newsletter in the archive.
RESEARCH HIGHLIGHTS:
Forcing Cancer Cells to ‘Breathe’ Could Kill ‘em
Guessing Your Next Move
Neurons Discover Their Inner Child
A Quarter-Century of Saving Lives
p53 Sends Death Order to Tiny Killer
NEWS BRIEFS:
Maryland Stem Cell Research Commission Funds 15 Hopkins Researchers
RESEARCH HIGHLIGHTS:
5/8/07 Forcing Cancer Cells to ‘Breathe’ Could Kill ‘em
Cancer cells, especially those buried deep in solid tumors, often grow under extremely low oxygen conditions. Studying Von Hippel-Lindau kidney cancer cells, Gregg Semenza and colleagues have discovered that loss of the VHL gene counteracts the oncogene MYC, which normally promotes mitochondrial synthesis. VHL cells stop making mitochondria, leaving them to fuel their growth by fermentation. While less efficient, fermentation requires no oxygen and therefore produces no DNA-damaging free radicals. Adding VHL back to cells increased mitochondrial synthesis and oxygen consumption, and produced more free radicals, which can cause cancer cells to stop dividing and die.
Read the paper here.
Read the news release here.
5/13/07 Guessing Your Next Move
Reza Shadmehr and colleagues in biomedical engineering have developed a computer model that uses a statistical analysis known as Bayesian theory to explain how the brain draws on both its recently learned and long-term memory to anticipate future movements. The biomedical engineer team exploited the fact that all people show similar learning patterns when developing or fine-tuning motor skills. This new model, which compiles the prior knowledge and uncertainty about each imminent move to calculate the optimal response, could be used to design optimal physical therapy regimens for the disabled or impaired.
Read the paper here.
Read the news release here.
5/24/07 Neurons Discover Their Inner Child
Newly made nerves in the adult hippocampus, the brain’s center for learning and memory, experience a one-month period when they are just as active as the nerves in a child, Hongjun Song and colleagues in neuroscience have found. The researchers tracked the chemical signals received by nerves in adult mice through the use of fluorescent virus particles. They saw that nerves between 1 and 2 months of age could dramatically modulate the amount of signaling chemicals they receive from neighbors. This signal modulation, or synaptic plasticity, is high in developing brains but decreases in adults. This study therefore suggests that new adult nerves have a deeper role than simply replacing dead ones.
Read the paper here.
Read the news release here.
5/31/07 A Quarter-Century of Saving Lives
Inherited mutations in any of six genes involved in ridding the body of nitrogenous waste through the urea cycle can cause toxic, elevated levels of ammonia in the blood. Urea cycle disorder-induced hyperammonemia causes brain damage and is fatal if not properly treated. In 1979, Saul Brusilow and colleagues in Pediatrics discovered that giving patients two chemicals that also can carry waste nitrogen out of the body alleviates hyperammonemia. Genetic Medicine’s Ada Hamosh, Brusilow and other colleagues around the country now have analyzed the outcomes of 299 children treated over 25 years and found that with timely diagnosis and treatment more than 80 percent survived.
Read the paper here.
Read the news release here.
5/31/07 p53 Sends Death Order to Tiny Killer
The tumor suppressor p53 is one of the most commonly mutated genes in human cancer. And several chromosome aberrations found in cancer cells have pointed to microRNA genes. Josh Mendell, Charlie Lowenstein, Anirban Maitra and colleagues now have discovered that p53 can activate the mir-34a microRNA gene and mir-34a in turn modulates genes involved in cell cycle control and DNA repair and promotes programmed cell death. Mir-34a’s suspected tumor suppressor activity is supported by the fact that of 11 different pancreatic cancer cell lines examined, most contain little or no active mir-34a.
Read the paper here.
Read the news release here.
NEWS BRIEFS:
5/17/07 Maryland Stem Cell Research Commission Funds 15 Hopkins Researchers
Of the 86 total applications filed under the Maryland Stem Cell Research Act of 2006, 24 were recommended for funding and 15 are here at Johns Hopkins.
Angelo All of the Whitaker Biomedical Engineering Institute
"Human Embryonic Stem Cell-Derived Oligodendrocytes and Electrophysiological Studies in a Contusion Model of Spinal Cord Injury in the Rat"
Shyam Biswal of the Bloomberg School of Public Health
"Nrf2 as a Target for Cancer Stem Cell Chemoresistance"
Jeff Bulte of the School of Medicine
"Human Embryonic Stem Cell-Derived Neurospheres for Treatment of Multiple Sclerosis"
Srinivasan Chandrasegaran of the Bloomberg School of Public Health
"Targeted Engineering of the Human Genome in Stem Cells"
Curt Civin of the Kimmel Cancer Center
"MicroRNA Regulation of Adult and Embryonic Human Hematopoietic Development"
Nancy Craig of the School of Medicine
"Genome Engineering of Human Stem Cells for Gene Therapy"
Candace Kerr of the School of Medicine
"Defining Genes Associated with Human Stem Cell Pluripotency and Self-Renewal"
Hai-Quan Mao of the Whiting School of Engineering
"Engineering an Artificial Neural Stem Cell Niche"
Andrew McCallion of the School of Medicine
"Illuminating Human Cardiac Development and Disease through Transcriptional Analysis in Differentiating Human Embryonic Stem Cells"
Guo-li Ming of the School of Medicine
"Mechanisms Regulating Self Renewal of Human Embryonic Stem Cells"
Akhilesh Pandey of the School of Medicine
"Proteomic Characterization of Neural Differentiation in Human Embryonic Stem Cells"
Hamid Rabb of the School of Medicine
"Isolation, Expansion and Regenerative Potential of Human Adult Kidney-Derived Stem Cells"
Hongjun Song of the School of Medicine
"Characterization of Neuronal Potentials of Human Embryonic Stem and Adult Neural Stem Cells"
Elias Zambidis of the Kimmel Cancer Center
"Human Embryonic Stem Cell Models of Normal and Leukemic Human Stem Cell"
Karen Zeller of the School of Medicine
"Myc's Role in Maintenance and Tumorigenicity of Human Embryonic Stem Cells"
Read the news release here.
Find more Hopkins news here.
