Cancer-associated fibroblasts-induced GAS6 increases resistance to chemotherapy through AXL/STAT3/ABCG1 axis signaling pathway in gastric cancer
암관련섬유모세포 유래 GAS6가 위암 세포의 AXL/STAT3/ABCG1 신호 전달을 통해 항암화학요법 저항성 증가에 관여하는 기전과 그 억제방안에 대한 연구
- 주제(키워드) Gastric cancer , Tumor microenvironment , Growth arrest-specific 6 , Cancer-associated fibroblasts
- 주제(DDC) 570
- 발행기관 아주대학교 일반대학원
- 지도교수 Hoon Hur
- 발행년도 2024
- 학위수여년월 2024. 2
- 학위명 박사
- 학과 및 전공 일반대학원 의생명과학과
- 실제URI http://www.dcollection.net/handler/ajou/000000033388
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
Cancer-associated fibroblasts-induced GAS6 increases resistance to chemotherapy through AXL/STAT3/ABCG1 axis signaling pathway in gastric cancer. The growth arrest-specific 6 (GAS6)/AXL signaling pathway plays a crucial role in cancer-associated fibroblast (CAFs)-induced gastric cancer progression. However, the therapeutic applications of drugs targeting the interactions between GC cells and CAFs have not yet been implemented. In this study, we aimed to examine the efficacy of a novel AXL inhibitor with high selective potency to reduce CAFs-induced aggressiveness and chemoresistance in GC. The expression of GAS6 was higher in CAFs than that in other cells. Co-culture with CAFs increased AXL phosphorylation and promoted migration, downstream activation, and chemoresistance in GC cells. However, these effects decreased in CAFs treated with 9im, a small-molecule AXL inhibitor. Microarray analysis revealed that expression of ABCG1 (a key factor in the development of chemoresistance) and drug efflux increased in GC cells co-cultured with CAFs; however, 9im inhibited these effects. The STAT3 transcription factor was shown to bind to the ABCG1 promoter, and ABCG1 expression was decreased in a dose-dependent manner by the STAT3 inhibitor. Moreover, human GC tumors expressed high levels of ABCG1 and CAF markers, and their expression correlated with a worse prognosis. Overall, this study demonstrates that CAFs-derived GAS6 is a major mediator of CAFs-induced chemoresistance in GC and that GAS6/AXL/STAT3 axis signaling activates ABCG1, which may present CAFs-induced chemoresistance as a specific key mechanism. The findings suggest that a combination strategy involving chemotherapy with an AXL inhibitor may enhance the therapeutic efficacy of chemotherapy in GC treatment.
more목차
I. INTRODUCTION 1
II. MATERIALS AND METHODS 4
1. Cell lines and cell culture 4
2. Preparation of conditioned media (CM) 4
3. Co-culture with GC cells and treatment 4
4. Transwell migration assay 5
5. Cell viability assay 5
6. RNA isolation and quantitative reverse transcriptase PCR (qRT-PCR) 6
7. Reverse transcriptase PCR (RT-PCR) 6
8. Enzyme-linked immunosorbent assay (ELISA) 7
9. Flow cytometry 8
10. Western blotting 8
11. Drug efflux assay 9
12. Luciferase assay 10
13. Immunocytochemistry (ICC) 11
14. Immunohistochemical staining (IHC) 11
15. Small interfering RNA (siRNA) 12
16. Animal model study 12
17. Microarray 13
18. Public data 13
19. Statistical analysis 14
III. RESULTS 15
1. 9im inhibits activation of AXL by CAFs-derived GAS6 in GC cells 15
2. Comparison between the effects of BGB324 and 9im in the viability of non- cancerous cells and inhibition of AXL activation in GC cells 23
3. The GAS6/AXL axis signaling pathway was essential in CAFs-induced migration of GC cells 26
4. Combined treatment of 9im and chemotherapeutic agents suppressed the CAFs-induced chemoresistance in GC cells 29
5. Genetic inhibition of GAS6/AXL axis suppresses the CAFs-induced chemoresistance in GC cells 39
6. ABCG1 is a key molecule of CAFs-induced chemoresistance in GC cells 50
7. ABCG1 and GAS6 expression is associated with poor prognosis in GC patients 67
IV. DISCUSSION 72
V. REFERENCES 76
국문요약 82
