Monthly Archives: January 2014

PUBLIC RELEASE DATE:

8-Jan-2014

Contact: David McKeon DMckeon@nyscf.org 212-365-7440 New York Stem Cell Foundation

NEW YORK, NY (January 8, 2014) Scientists at The New York Stem Cell Foundation (NYSCF) Research Institute in collaboration with scientists at the Icahn School of Medicine at Mount Sinai (ISMMS) successfully generated a stem cell model of familial Alzheimer's disease (FAD). Using this stem cell model, researchers identified fourteen genes that may be implicated in the disease and one gene in particular that shows the importance that inflammation may play in the brain of Alzheimer's patients.

In this study, published today in PLOS ONE, the team of scientists produced stem cells and neural precursor cells (NPCs), representing early neural progenitor cells that build the brain, from patients with severe early-onset AD with mutations in the Presenilin 1 (PSEN1) gene. These NPCs had elevated Abeta42/Abeta40 ratios, indicating elevation of the form of amyloid found in the brains of Alzheimer's patients. These levels were greater than those in adult cells that did not have the PSEN1mutation. This elevated ratio showed that these NPCs grown in the petri dish were accurately reflecting the cells in the brains of FAD patients.

"Our ability to accurately recapitulate the disease in the petri dish is an important advance for this disease. These genes provide us with new targets to help elucidate the cause of sporadic forms of the disease as well provide targets for the discovery of new drugs," said Susan L. Solomon, Chief Executive Officer of The New York Stem Cell Foundation.

"The gene expression profile from Noggle's familial Alzheimer's stem cells points to inflammation which is especially exciting because we would not usually associate inflammation with this particular Alzheimer's gene. The greatest breakthroughs come with 'unknown unknowns', that is, things that we don't know now and that we would never discover through standard logic," said Sam Gandy, MD, PhD, Professor of Neurology and Psychiatry and Director of the Center for Cognitive Health at the Icahn School of Medicine at Mount Sinai and a co-author on the study. Gandy is also Associate Director of the NIH-Designated Mount Sinai Alzheimer's Disease Research Center.

The researchers generated induced pluripotent stem (iPS) cells from affected and unaffected individuals from two families carrying PSEN1 mutations. After thorough characterization of the NPCs through gene expression profiling and other methods, they identified fourteen genes that behaved differently in PSEN1 NPCs relative to NPCs from individuals without the mutation. Five of these targets also showed differential expression in late onset Alzheimer's disease patients' brains. Therefore, in the PSEN1 iPS cell model, the researchers reconstituted an essential feature in the molecular development of familial Alzheimer's disease.

Although the majority of Alzheimer's disease cases are late onset and likely result from a mixture of genetic predisposition and environmental factors, there are genetic forms of the disease that affect patients at much earlier ages. PSEN1 mutations cause the most common form of inherited familial Alzheimer's disease and are one hundred percent penetrant, resulting in all individuals with this mutation getting the disease.

The identification of genes that behaved differently in patients with the mutation provides new targets to further study and better understand their effects on the development of Alzheimer's disease. One of these genes, NLRP2, is traditionally thought of as an inflammatory gene.

Originally posted here:
Stem cell research identifies new gene targets in patients with Alzheimer's disease

PUBLIC RELEASE DATE:

8-Jan-2014

Contact: Darrell E. Ward Darrell.Ward@osumc.edu 614-293-3737 Ohio State University Wexner Medical Center

COLUMBUS, Ohio Currently, doctors use chromosome markers and gene mutations to determine the best treatment for patients with acute myeloid leukemia (AML). But a new study suggests that a score based on seven mutated genes and the epigenetic changes that the researchers discovered were also present might help guide treatment by identifying novel subsets of patients.

The findings, published in the Journal of Clinical Oncology, come from a study led by researchers at The Ohio State University Comprehensive Cancer Center Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC James).

The epigenetic change used in the study is DNA methylation. It involves the addition of methyl groups to DNA, which can reduce or silence a gene's activity, or expression. Abnormal DNA methylation alters normal gene expression and often plays an important role in cancer development.

Overall, the findings suggest that patients with a low score indicating that one or none of the seven genes is overexpressed in AML cells had the best outcomes, and that patients with high scores that is, with six or seven genes highly expressed had the poorest outcomes.

"To date, disease classification and prognostication for AML patients have been based largely on chromosomal and genetic markers," says principal investigator Clara D. Bloomfield, MD, Distinguished University Professor, Ohio State University Cancer Scholar and Senior Adviser.

"Epigenetic changes that affect gene expression have not been considered. Here we show that epigenetic changes in previously recognized and prognostically important mutated genes can identify novel patient subgroups, which might better help guide therapy," says Bloomfield, who is also the William Greenville Pace III Endowed Chair in Cancer Research at Ohio State.

The seven-gene panel was identified in 134 patients aged 60 and older with cytogenetically normal acute myeloid leukemia (CN-AML) who had been treated on Cancer and Leukemia Group B (CALGB)/Alliance clinical trials.

Continued here:
AML score that combines genetic and epigenetic changes might help guide therapy