$8.7 million awarded to stem cell researchers in clinical & basic biology grants from the state stem cell agency

Sep 06, 2012 Awards & Funding

Dr. Stanley Nelson, a scientist with the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA, was awarded a $6 million grant from the state stem cell agency today to develop a combination therapy for Duchenne Muscular Dystrophy (DMD), a potentially fatal disease that currently has no effective treatment.

Two other scientists with the Broad Center, Dr. Owen Witte and Kathrin Plath were awarded more than $2.7 million dollars in two grants from the state stem cell agency to investigate basic mechanisms underlying stem cell biology and differentiation.

Nelson’s Early Translational award and the two Basic Biology IV grants –totaling $8.7 million –continue efforts by the California Institute of Regenerative Medicine (CIRM) to support research designed to take stem cell science from the laboratory to the clinic. The studies supported by these awards will form the foundation for translational and clinical advances, enabling realization of the potential of human stem cells for therapies and as tools for biomedical innovation.

To date, UCLA and its stem cell scientists have received 57 grants from CIRM totaling more than $182.7 million.

 “It is very rewarding to see the breadth and quality of the basic science translation to clinical applications at UCLA’s stem cell center recognized with the awarding of these grants,” said Witte, director of the UCLA Broad Stem Cell Research Center. “The science supported by them will propel future translational and clinical research such as that being done by the Nelson team and hopefully result in more new and effective therapies for a host of diseases.”

The Broad Stem Cell Research Center researchers receiving grants are Nelson, a professor and vice chair of Human Genetics and Psychiatry ($6 million); Witte, a professor of Microbiology, Immunology and Molecular Genetics in the Life Sciences and a Howard Hughes Medical Institute Investigator ($1.38 million); and Plath, associate professor of Biological Chemistry ($1.38 million).

Nelson will develop a combination therapy for DMD, an inherited disease that affects about 1 in 3,600 boys and results in muscle degeneration and eventual death. This research was supported strongly by parents of children with DMD during the last CIRM meeting. Teaming up for the project are Broad Stem Cell Research Center members Nelson and his wife, scientist Carrie Miceli, a professor of Microbiology, Immunology and Molecular Genetics in the Life Sciences.

In the disease, a genetic mutation occurs that results in a completely non-functional dystrophin protein, which leads to the severe symptoms of DMD. An exon or exons are deleted in the mutated DMD gene, which interferes with its function. One way to address this is exon skipping, which encourages the cellular machinery to “skip over” an exon. Small pieces of DNA called antisense oligonucleotides (AOs) or molecular patches are used to mask the exon that you want to skip. 

A drug has been identified through the use of muscle stem cells that can enhance the effectiveness of exon skipping by AOs to the DMD gene to restore dystrophin expression and at least partially correct the defect responsible for loss of muscle function. Nelson and Miceli propose to test the effectiveness of a combination therapy composed of an AO with an FDA-approved drug that boosts its activity, a therapy discovered at UCLA.

The study will use patient-derived stem cells as a novel therapeutic strategy. DMD generally leads to death in the teens or early 20s, making it one of the most severe disorders in humans and one of the most common genetic disorders. There currently are no effective therapies.

Witte has contributed to the recent scientific progress that identified normal prostate tissue stem cells and the biological mechanisms that regulate their growth. These mechanisms are called regulatory signaling pathways and work like telephone lines between cells that tell them how and when to grow.

Human cancer cells use those same pathways to grow into tumors. Witte recently discovered a molecule called Trop2 that is key to making the pathways work. Trop2 was found in cells from advanced-stage prostate cancer that have the ability to make tumors grow back. Trop2 can also appear in other cancer cells and its presence can predict poor outcomes in many different types of cancer, including ovarian, pancreas, breast, stomach, colon and rectal cancers.

Witte intends to develop a combination of treatments that will block Trop2 and other pathways to prevent cancer progression and recurrence. This novel combination could significantly extend life and reduce suffering of men with advanced prostate cancer and may benefit patients with many other types of cancer.  

Human embryonic stem cells can become any cell in the human body, giving them the potential to revolutionize modern medicine with stem cell-based therapies. Male stem cells have an X chromosome and a Y chromosome, the parts of DNA that carry hereditary information, while female cells have two X chromosomes. Female cells use a mechanism called X chromosome inactivation to shut down one X chromosome, so there is a balance with the male cells that have only one X chromosome. When this shut down happens is not clear.

When embryonic stem cells are grown in the laboratory, some have X chromosome inactivation while others have two active X chromosomes. This makes the cells unstable for use in therapies, and why this difference in X chromosome state happens is unknown.  For scientists to use stem cells in therapies, they need to be able to grow high-quality, stable cells that have the same X chromosome state.

Plath will focus her research on the X chromosome to determine why the cell instability happens, and find biological markers that can be used as benchmarks to assess the quality and X chromosome stability of stem cells, which will allow scientists to grow high-quality stem cells for future treatments.