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Blood Stem Cell Clonality and the Niche

Wednesday, November 17, 2021 - 3:00pm to 4:00pm


Leonard Zon, M.D.
HHMI Investigator
Grousbeck Professor of Pediatric Medicine, Harvard Medical School
Director, Stem Cell Program at Boston Children's Hospital
Harvard Medical School

Dr. Leonard I. Zon is the Grousbeck Professor of Pediatric Medicine at Harvard Medical School, Investigator at Howard Hughes Medical Institute, and Director of the Stem Cell Program, Children’s Hospital Boston. He is founder and former president of the International Society for Stem Cell Research and chair of the Executive Committee of the recently formed Harvard Stem Cell Institute (HSCI). In 2005, he completed a term as President of the American Society for Clinical Investigation. In that same year, Dr. Zon was elected to the Institute of Medicine of the National Academies. In 2008, Dr. Zon was elected to the American Academy of Arts & Sciences and in 2010, Dr. Zon was awarded the E. Donnall Thomas Lecture and Prize from American Society of Hematology. In 2013, Dr. Zon received the ISEH Donald Metcalf Lecture Award and in 2017, the AACR-Irving Weinstein Foundation Distinguished Lecture Award.

Dr. Zon is internationally recognized for his pioneering work in the fields of stem cell biology and cancer genetics. He has been the pre-eminent figure in establishing the zebrafish as an invaluable genetic model for the study of the blood and hematopoietic development. The laboratory focuses on the developmental biology of hematopoiesis and cancer. They have collected over 30 mutants affecting the hematopoietic system. Some of the mutants represent excellent animal models of human disease. They also have undertaken chemical genetic approach to blood development and have found that prostaglandins upregulates blood stem cells. This has led to a clinical trial to improve engraftment for patients receiving cord blood transplants. They recently developed suppressor screening genetics and found that transcriptional elongation regulates blood cell fate. The laboratory has also developed zebrafish models of cancer. They have generated a melanoma model in the zebrafish system using transgenics. Transgenic fish get nevi, and in a combination with a p53 mutant fish develop melanomas. They recently found a histone methyltransferase that can accelerate melanoma, and discovered a small molecule that blocks transcription elongation and suppresses melanoma growth.


Dr. Zon will discuss two critical avenues of his current research: identifying the genes that direct stem cells to become cancers or to develop into more specialized blood or organ cells; and developing chemical or genetic suppressors to cure cancers and many other devastating diseases. In the past five years, his lab has collected more than 30 mutants affecting the hematopoietic system. Several represent excellent animal models of human disease. More recently, the lab has developed hematopoietic cell transplantation for the zebrafish using blood cells labeled with green fluorescent protein and DSred, which has enabled the research team to image the hematopoietic cells as they migrate to the marrow and to the thymus. 

The page was last updated on Tuesday, December 7, 2021 - 5:03pm