Stem Cells Junfeng Ji ( 纪俊峰 ), PhD Professor Research Center of Stem Cell and Developmental Biology School of Medicine Zhejiang University Email: jijunfeng@zju.edu.cn Dec 04, 2013
Totipotent Pluripotent Multipotent /mucosa /enamel /cartilage/denti n
- Induced pluripotent stem cells (ipscs)
Pluripotent Stem Cells
Mario R. Capecchi Sir Martin J. Evans Oliver Smithies "f hidi i f i i l f i d i "for their discoveries of principles for introducing specific gene modifications in mice by the use of embryonic stem cells".
2006 Terese Winslow
Ethical Concerns with human ES derivation propel the discovery of reprogramming/ips technology
Sir John B. Gurdon Shinya Yamanaka The Nobel Prize in Physiology or Medicine 2012 was awarded jointly to Sir John B. Gurdon and Shinya Yamanaka "for the discovery that mature cells can be reprogrammed to become pluripotent"
Reprogramming Yamanaka S and Blau HM, Nature 2010 456.
Human ES Cells derived by somatic cell nuclear transfer Tachibana et al Cell 2013 153(6): 1228-1238.
Reprogramming by defined factors Induced Pluripotent Stem Cells (ipscs)
ipscs technology for drug screening
Disease Modeling Cell. Volume 148, Issue 6, 2012, Pages 1110 1122.
Personalized Regenerative Medicine
Safety Concerns
Klf4 Oct4 Sox2 Myc 1. Ectopic Expression of Oct 4 Blocks Progenitor Cell Differentiation and Causes Dysplasia yp in Epithelial Tissues. Cell. 2005 121(3): 465 477. 2. SOX2 isan amplifiedlineage survivaloncogenelineage survival in lung and esophagealsquamous squamous cellcarcinomas carcinomas. Nature Genetics. 2009. 41(11):1238 42. 3. The KLF4 tumour suppressor is a transcriptional repressor of p53 that acts as acontext dependent oncogene. Nature cell biology. 2005. 7(11): 1074 1082. 4. MYC oncogenes and human neoplastic disease. Oncogene. 1999. 18(19):3004 16.
Oncogene activation DNA double strand break p53 Apoptosis/Senescence DNA repair
Reprogramming induced mutations make a major contribution to the overall mutational load of ips Cells 7 % 19 % Class I :Pre existing mutations Class II ClassIII :Reprogramming induced mutations :Passaging induced mutations 74 % Ji et al. Stem Cells 2012; 30:435 440.
Immunogenecity
Hematopoietic Stem Cells
www.allthingsstemcell.com
2005 Albert Lasker Basic Medical Research Award Ernest McCulloch and James Till for ingenious experiments that first identified a stem cell the blood forming stem cell which set the stage for all current research on adult and embryonic stem cells
Colony Forming Unit Spleen (CFU S) assay
In the early 1960s, McCulloch and Till started a series of experiments that involved injecting bone marrow cells into irradiated mice. Visible nodules were observed in the spleens of the mice, in proportion to the number of bone marrow cells injected. Till and McCulloch called the nodules 'spleen colonies', and speculated that each nodule arose from a single marrow cell: perhaps a stem cell.
McCulloch, E.A., Till, J.E. (1960) The radiation sensitivity of normal mouse bone marrow cells, determined by quantitative marrow transplantation into irradiated mice. Radiation Research 13(1):115 125. Till, J.E., McCulloch, E.A. (1961) A direct measurement of the radiation sensitivity of normal mouse bone marrow cells. Radiation Research 14:213 22. Becker, A.J., McCulloch, E.A., Till, J.E. (1963) Cytological demonstration of the clonal nature of spleen colonies derived from transplanted mouse marrow cells. Nature 197:452 4 4. Siminovitch, L., McCulloch, E.A., Till, J.E. (1963) The distribution of colony forming cells among spleen colonies. Journal of Cellular and Comparative Physiology 62:327 36. Till, J.E., McCulloch, E.A., Siminovitch, L. (1964) A stochastic model of stem cell proliferation, based on the growth of spleen colony forming cells. Proceedings of the National Academy of Sciences (USA) 51(1):29 36.
Irving Weissman
HSCs isolation and assays 2006 Terese Winslow
Ontogeny of the Hematopoietic System Image from Paterson Institute for Cancer Research
HSCs and niche JEM 2011 208 (3): 421-428
Bone marrow transplantation www.scripps.org
The Nobel Prize in Physiology or Medicine 1990 was awarded jointly to Joseph E. Murray and E. Donnall Thomas "for their discoveries concerning organ and cell transplantation in the treatment of human disease" Joseph E. Murray E. Donnall Thomas
World-wide shortage of Bone Marrow Transplantation
Research Directions 1. Additional cell sources: Derivation of HSC from human pluripotent stem cells 2. Expansion of HSCs in vitro
Cancer Stem Cell
The 3 rd Nobel Prize for Stem Cells? 3659 citations
The Cancer Stem Cell Model Like normal stem cells, only a small subpopulation of cells, called cancer stem cells (CSC), can selfrenew and give rise to differentiated cancer cells in the tumour. The cells in a tumour are hierarchically organized. Only CSCs di drive the tumour growth.
The Stochastic Model All cancer cells have the same potential to grow and divide, but each cell randomly chooses between self-renewal and differentiation. The cells in a tumour are not in an organized system any cell has the same intrinsic potential to contribute to tumour growth.
Controversies on Cancer Stem Cell Model
The existence of cancer stem cells in vivo
The cell origin of cancer?
Similar Marker Expression on Normal and Cancer Stem Cells Hematopoietic stem cells (HSCs) Leukemia-initiating cells (HSCs) CD34, CD133 Intestinal stem cells (ISCs) Intestinal cancer stem cells Lgr 5 Neural stem cells (NSCs) Glioma stem cells Nestin
Common signaling pathways that regulate normal stem cell self-renewal and tumorigenesis Reya et al. Nature 2001
Reya and Clevers. Nature 2005
Matthew C. Stubbs and Scott A. Armstrong. Clin Cancer Res 2007;13:3439-3442
How to specifically target cancer stem cells?
Quiz 1. What is therapeutic cloning? 2. What is the pluripotency?