검색 상세

Characteristic analysis of mobility inducers for neural stem cells

신경줄기세포에 대한 이동성 유도물질들의 특성 분석

초록/요약

Recently neural stem cells (NSCs) were reported to migrate to damaged brain areas, such as brain tumors or ischemic regions. Systemic strategy can be effective to cancer therapeutic effect through cell-based gene therapy. From our previous studies, we identified chemoattractant molecules-1(CM-1) and CM-2 as novel chemoattractants that induced tumor-tropism of neural stem cells, and showed that CM-1 accelerated tumor tropism of human NSCs encoding therapeutic gene and increased targeting in vivo model of rats. Previous our results showed that in rats transplanted with NIH 3T3 cells overexpressing CM-1 and glioma cells, the edge of tumor mass did not infiltrate and invasive tumor cells were eliminated from surrounding region compared with only glioma cells. So, we examined that CM-1 bound to the integrin αvβ5, known as candidate CM-1 receptor in NSCs and resulted in promoting activation of signal pathway for mobility. In migration assay using functional blocking antibody, we identified that integrin αvβ5 interacted with CM-1 and induced functional cell migration in human glioblastoma primary cultured cells and rat glioma cells as well as human NSCs. In the presence of CM-1, NSC migrated toward opposite area significantly compare with control group. According to that, CM-1 made brain cancer stem cells to assemble toward tumor mass. To investigate whether CM-1-induced NSC migration can have in vivo therapeutic efficacy, we determined survival time of brain tumor animal model transplanted with NSC harboring suicidal gene and CM-1. The result of the in vivo experiment for CM-1 showed that human NSCs encoding cytosine deaminase (CD) migrated towards co-transplantation sites of NIH3T3 cells overexpressing CM-1 and glioma cells compared to only glioma cells. In addition, bystander effect by repetitive infusion of prodrug, 5-fluorocytosine (5-FC), reduced tumor mass with increasing number of CM-2-expressing cells. Transplanted group of CM-1-producing NIH 3T3 cells significantly extended survival time over 105 days than transplantation of glioma cells. PET imaging data showed that increase of survival correlated with reduction of tumor mass volume. Our previous study showed that, the other Chemoattractants molecule, CM-2 induced NSCs migration by interacting with CD63 and CM-2-CD63complex bound to integrin β1. To investigate the detailed molecular mechanism for NSCs migration by CM-2, in migration assay, we confirmed that integrin β1 and PI3K signaling pathways were implicated in the induction of NSCs migration via CM-2. We investigated phosphorylation of tyrosine 397 site of FAK by using CD63-downregulated HB1.F3 cells with shRNA strategy and pREP4 F3 cells. Our results showed that human NSCs activated phosphorylation of FAK by CM-2 for migration with the exception of shCD63 knockout NSCs. These findings provide us an important step towards the development of new NSCs based gene therapies to cure brain tumor and hold promise for use as a therapeutic approach to treat aggressively invasive gliomas such as glioblastoma multiforme.

more

목차

ABSTRACT ⅰ
TABLE OF CONTENTS ⅲ
LIST OF FITURES Ⅴ
Ⅰ. INTRODUCTION 1
Ⅱ. MATERIAL AND METHODS 6
A. Cells and cell culture 6
B. Brain tumor animal model 6
C. 5-FC treatment 7
D. PET scan and tumor volume evaluation 7
E. Blocking antibody migration assay 8
F. Boydenchamber assay 9
G. Western blot analysis 9
Ⅲ. RESULTS 11
A. Cancer stem cells induced migration by CM-1 via integrin αvβ5 as receptor of CM-1 as well as NSCs 11
B. Systemic strategy using CM-1 as chemoattractants and CD-5-FC was effective to prolong survival time 15
C. CM-2 was crucial interaction with integrin β1 in induction of NSCs migration 21
D. FAK and PI3K signal pathway were involved in the NSCs migration 23
Ⅳ. DISCUSSION 26
Ⅴ. CONCLUSION 29
REFERENCES 30
국문요약 35

more
반출 Meta View 목록