Presentation is loading. Please wait.

Presentation is loading. Please wait.

THE PROMISE OF STEM CELL RESEARCH Marisa Bowers Donghong Zhao Karen S. Aboody, M.D. et al. Assistant Professor Divisions of Hematology/HCT & Neurosciences.

Similar presentations


Presentation on theme: "THE PROMISE OF STEM CELL RESEARCH Marisa Bowers Donghong Zhao Karen S. Aboody, M.D. et al. Assistant Professor Divisions of Hematology/HCT & Neurosciences."— Presentation transcript:

1 THE PROMISE OF STEM CELL RESEARCH Marisa Bowers Donghong Zhao Karen S. Aboody, M.D. et al. Assistant Professor Divisions of Hematology/HCT & Neurosciences City of Hope National Cancer Center & Beckman Research Institute COH Summer Student Program June 26, 2005

2 MBowers/Aboody Lab 2005 Outline Background Information/Definitions Neural Stem Cell Migration Migration Assays Migration Data and Results Future Experiments

3 MBowers/Aboody Lab 2005 Background – Stem Cells What is a Stem Cell? -undifferentiated cell has potential to differentiate into some/all cell types in body What is a Neural Stem Cell? -differentiate into neuron, astrocyte or oligdendrocyte What are the potential therapeutic benefits of stem cells? -exogenous stem cells repair damaged/diseased tissue -deliver therapeutic agents to tumors -prevent/treat birth defects in womb

4 MBowers/Aboody Lab 2005 Background - Glioblastoma What is Glioblastoma? -Type of human brain cancer -Highly invasive: metastasizes quickly throughout brain, surgeons remove main tumor mass, missing metastases -Expected life-span of a patient with glioma is 3-6 months -No cure

5 MBowers/Aboody Lab 2005 Past and Present Glioma Research Previous research: drug delivery -through gene therapy -problem with drug delivery: no movement of cells within tissue, does not target metastases -blood-brain barrier prohibits entry of some therapeutic agents into brain Potential Solution: neural stem cells as vehicles -targeted delivery of therapeutic agents

6 MBowers/Aboody Lab 2005 NSC’s Directed Migration to Tumor Cells Cancer cell Stem cell

7 MBowers/Aboody Lab 2005 Why does Directed Migration of NSC’s to Tumor Cells Occur? Theories: -tumor cells excrete cytokines, attract stem cells -pockets of hypoxia exist within tumor mass, draws stem cells -genes expressed in cells different in hypoxic (1%O 2 ) and normoxic (16%O 2 ) conditions My Project: Determine factors involved in NSC migration to tumor Hypothesis: one or more of the following cytokines effects NSC migration under hypoxic conditions -SDF-1/CXCR-4 -HGF/C-Met -SCF/CKit -VEGF/VEGFR -EGF/EGFR -IL8/IL8R signaling pathways Stat3, RaS and Wnt are downstream of genes code for cytokines, pathway effected by cytokine expression Tumor Cell NSC

8 MBowers/Aboody Lab 2005 Initial Tests: Boyden Chamber Migration Assays

9 MBowers/Aboody Lab 2005 Variable Conditions: -Upper Chamber: -NSC grown at 16%O 2 -NSC grown at 16% then incubated 24 hours at 1%O 2 -Lower Chamber: -tumor CM from tumor cells incubated 48 hours under 16%O 2 -tumor CM from tumor cells incubated 48 hours under 1%O 2 -media containing different levels of serum Boyden Chamber Migration Set-up

10 MBowers/Aboody Lab 2005 Controls: -DMEM/RPMI -5%BSA -10%FBS Tumor CM -16%O 2 U251 -1%O 2 U251 -16%O 2 U251 +SDF-1 -16%O2 SKNAS -1%O 2 SKNAS -16%O 2 SKNAS +SDF-1 Lower Wells Boyden Chamber Set-Up 16%O 2 F3.C11%O 2 F3.C1 Upper Wells

11 MBowers/Aboody Lab 2005 U251 Graph 16%O 2 Plate 1%O 2 Plate

12 MBowers/Aboody Lab 2005 SKNAS Graph 16%O 2 Plate 1%O 2 Plate

13 MBowers/Aboody Lab 2005 Migration Results Effect of SDF-1 on Migration -no effect on migration -seen repeatedly in assays -either not involved in migration or levels of SDF-1 high prior to migration, additional SDF-1 no effect Effect of VEGFR on Migration -normoxic and hypoxic plates: blocked/hindered migration -may be migration inducing factor

14 MBowers/Aboody Lab 2005 Future Experiments Changes for future experiments: -culture stem cells in 1%O 2 for less than 24 hours -run many tests to find good time span -real time-PCR on SC cultured for different amounts time -use U251 and Brain cell line 5904, not SKNAS -SKNAS: lower response to F3.C1 SC Repeat Boyden Chamber -making changes -compare migration results

15 MBowers/Aboody Lab 2005 Next Step Extract stem cell RNA and perform real time-PCR - Use mRNA expression to determine regulation of candidate ‘homing’ genes during migration

16 MBowers/Aboody Lab 2005 Use female immune compromised nude mice -inject mice with: -‘normal’ human brain tumor or - HIF siRNA brain tumor: HIF expression blocked -decrease cytokine expression - both groups will receive injection of stem cells In Vivo Model

17 MBowers/Aboody Lab 2005 harvest mice, remove tumor tissue for RNA extraction and real time-PCR -determine gene expression of tumor tissue and NSC -expect: gene expression to be different in normal and HIF siRNA tumors -use immnuohistochemical staining compare distribution stem cells in brains -expect: more stem cells in normal tumor than HIF siRNA tumor Data Analysis

18 MBowers/Aboody Lab 2005 Thank You Dr. Karen Aboody Donghong Zhao, PhD The Aboody Lab The Barish Lab The Glackin/Flannigan Labs Queenie Du and the Summer Student Program


Download ppt "THE PROMISE OF STEM CELL RESEARCH Marisa Bowers Donghong Zhao Karen S. Aboody, M.D. et al. Assistant Professor Divisions of Hematology/HCT & Neurosciences."

Similar presentations


Ads by Google