Title Page

Contents

Abstract 8

Ⅰ. INTRODUCTION 10

Ⅱ. MATERIALS AND METHODS 11

1. Cell lines and cell culture 11

2. Cell proliferation assay 12

3. Flow cytometry 13

4. Cytotoxicity assay 14

5. Statistical analysis 15

Ⅲ. RESULTS 16

1. Protein expression screening of ADAM9 and MICA in GC cells. 16

2. Under 1μM regorafenib treatment on GC cells doesn't affect the cells. 18

3. ADAM9 was significantly decreased on dose dependent concentration of regorafenib. 20

4. MICA showed decrease on dose dependent concentration of regorafenib. 22

5. Regorafenib enhances NK cell mediated cytotoxicity of gastric cancer 24

Ⅳ. DISCUSSION 26

Ⅴ. CONCLUSION 27

REFERENCES 28

ABSTRACT IN KOREAN 29

Fig. 1. Screening of protein expression level in GC cells. 17

Fig. 2. Adequate regorafenib concentration. 19

Fig. 3. ADAM9 was decreased under dose dependent treatment conditions of regorafenib. 21

Fig. 4. MICA was decreased under regorafenib treated condition. 23

Fig. 5. NK mediated cytotoxicity in GC cell lines. 25