This story was originally posted on Center Times Plus on October 15, 2018.

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UT Southwestern Professor Dr. Sean Morrison, Director of the Children’s Medical Center Research Institute (CRI) at UT Southwestern, has been elected to the National Academy of Medicine (NAM), one of the highest honors in the fields of health and medicine.

Dr. Morrison, a Professor of Pediatrics at UT Southwestern known for his significant discoveries in stem cell biology and cancer, is among 75 new members and 10 international members of NAM announced today. With his election, 17 current UT Southwestern faculty members have now been inducted into the organization.

The NAM – formerly known as the Institute of Medicine – recognizes individuals who have demonstrated outstanding professional achievement and a commitment to service. Along with the National Academy of Sciences and the National Academy of Engineering, the NAM advises the nation and the international community on critical issues in health, medicine, and related policy.

“We are honored that the National Academy of Medicine has recognized the significance of Dr. Morrison’s research in stem cell and cancer biology,” said Dr. Daniel K. Podolsky, President of UT Southwestern Medical Center and a NAM member as well. “Dr. Morrison pioneered new methods to purify stem cells from multiple tissues and discovered molecular mechanisms that allow stem cells to persist throughout life and regenerate tissues after injury.”

“I am grateful for this recognition for my laboratory’s work, and particularly thankful for the support of my colleagues at UT Southwestern and Children’s Health,” said Dr. Morrison, also a Howard Hughes Medical Institute Investigator. “This is a remarkable environment in which to do science, with many inspiring colleagues.”

Dr. Morrison identified a series of genes required for stem cell self-renewal. Self-renewal is necessary for stem cells to persist throughout life and regenerate tissues after injury. Stem cell self-renewal mechanisms change over time to match the changing growth and regeneration demands of tissues during development and aging, his research showed. Dr. Morrison also discovered that tumor-suppressor genes are induced in aging stem cells, inhibiting the development of cancer but also reducing the ability of aging tissues to heal after injury.

The identity of the supporting cells that sustain stem cells was unknown prior to the Morrison laboratory identifying the specialized microenvironments, or niches, in blood-forming tissues that maintain stem cells. His team discovered that blood-forming stem cells reside adjacent to blood vessels where they depend on growth factors produced by endothelial cells and Leptin Receptor+ (LepR+) cells. The LepR+ cells are a major source of the growth factors that regulate stem cell maintenance, blood cell production, and the regeneration of the blood-forming system after chemotherapy or radiation therapy. The LepR+ cells also include skeletal stem cells that are a major source of bone and growth factors that maintain the adult skeleton.

“Sean Morrison’s successes at the forefront of discovering new knowledge about cancer, including the very ways that research is conducted, aptly merit the exceptional distinction of being elected as a member of the National Academy of Medicine,” said Christopher J. Durovich, President and Chief Executive Officer at Children’s Health. “Moreover, the leadership of Dr. Morrison while pursuing his vision for exploiting the intersection of cancer, stem cell biology and metabolism, has enabled Children's Medical Center Research Institute at UT Southwestern to move rapidly from a novel idea to a portfolio of leading laboratories making profound contributions to the health and well-being of everyone.”

Dr. Morrison, who joined UT Southwestern in 2011 as Director of CRI, earned a bachelor’s degree in biology and chemistry from Dalhousie University in Canada and a Ph.D. in immunology at Stanford University. He completed a postdoctoral fellowship in neurobiology at Caltech and directed the University of Michigan’s Center for Stem Cell Biology.

Dr. Morrison served as President of the International Society for Stem Cell Research in 2015-2016. At UT Southwestern, Dr. Morrison is also a Cancer Prevention and Research Institute of Texas (CPRIT) Scholar in Cancer Research and member of the Harold C. Simmons Comprehensive Cancer Center, the only NCI-designated Comprehensive Cancer Center in North Texas.

Current NAM members at UT Southwestern and the year of their induction are: Dr. Joseph Takahashi (2014), Dr. Daniel K. Podolsky (2009), Dr. Bruce Beutler (2008), Dr. Thomas Südhof and Dr. Luis Parada (2007), Dr. Ellen Vitetta (2006), Dr. Steven McKnight (2005), Dr. Helen Hobbs (2004), Dr. Eric Olson (2001), Dr. Norman Gant (2001), Dr. Kern Wildenthal (1999), Dr. Carol Tamminga (1998), Dr. Scott Grundy (1995), Dr. Jean Wilson (1994), Dr. Michael Brown (1987), and Dr. Joseph Goldstein (1987).