Human epidermal growth factor receptor 2/neu와 c-Jun N-terminal kinase의 상호작용이 위암세포의 이동과 침윤에 미치는 영향

학위논문 (석사)-- 서울대학교 대학원 : 의학과 종양생물학 전공, 2016. 2. 이병란.Purpose: Human epidermal growth factor receptor2 (HER2) is a crucial regulator of tumor progression, but the underlying molecular mechanisms remain unclear. Recent studies reported the association between HER2 and c-Jun N-terminal kinase (JNK) in breast cancerhowever, little is studied in gastric cancer (GC). The present study investigated the relationship between HER2 and JNK in relation to the metastatic potential in GC cells. Methods: HER2-overexpressing human GC cell lines SNU-216 and NCI-N87 were used. JNK activation was suppressed by treatment with SP600125 and HER2 expression was silenced by RNA interference. Western blot and semi-quantitative reverse transcription-PCR were used to detect the expressions of pHER2, HER2, pJNK, JNK and epithelial mesenchymal transition (EMT) markers. Cell growth was determined by crystal violet assay. Cell migration and invasion were assessed by a Transwell assay. Results: In both GC cell lines, pharmacological inhibition of JNK using SP600125 reduced cancer cell growth, migration, invasion and actin cytoskeleton organization. It also upregulated E-cadherin and downregulated Snail and Vimentin. HER2 silencing by lentivirus-mediated HER2 shRNA transfection blocked JNK activation. On the other hand, JNK inhibition reduced HER2 expression at the protein and mRNA levels in GC cells. Moreover, JNK inhibition in HER2-silenced GC cells induced further decrease in GC cell growth, migration and invasion compared to HER2 silencing alone. Conclusions: The interaction between HER2 and JNK synergistically contributes to the GC cell growth and metastatic potential in HER2-overexpressing GC cells. Thus, JNK may be an attractive target for the treatment of GC patients with a HER2-overexpressing GC.Introduction 1 Materials and methods 4 Cell culture 4 Pharmacological inhibition of JNK 4 Western blot 5 Assessment of cell growth 6 Cell invasion and migration assay 6 Immunofluorescence staining 7 Lentivirus-mediated shRNA silencing of HER2 8 Semi-quantitative reverse transcription-polymerase chain reaction (SQ RT-PCR) 9 Statistical analysis 10 Results 11 JNK activation was pharmacologically inhibited by treatment with SP600125 11 Pharmacological inhibition of JNK reduces the cell growth, migration and invasion 11 JNK inhibition regulates the expressions of epithelial-mesenchymal transition (EMT) markers 12 Crosstalk between HER2 and JNK exists in GC cell lines 14 JNK inhibitor exerts synergistic effect when combined with HER2 shRNA transfection 15 Discussion 26 References 38 국문초록 46Maste