Cyr61 induces gastric cancer cell motility/invasion via activation of the integrin/nuclear factor-kappaB/cyclooxygenase-2 signaling pathway.
OBJECTIVE
Cysteine-rich 61 (Cyr61/CCN1) is involved in many different types of tumor development and progression. Nonetheless, the role of Cyr61 in human gastric cancer has not yet been fully characterized.


METHODS
We addressed the issue by immunohistochemical staining of 81 gastric adenocarcinoma specimens. Liposome-mediated transfection was used to introduce a Cyr61 expression vector into gastric cancer AGS cell lines. Transfectants were tested in invasion assay by a Boyden chamber. Furthermore, a cyclooxygenase-2 (COX-2) reporter assay and gel mobility shift assay were done to investigate the potential signal pathway of Cyr61.


RESULTS
Patients with gastric adenocarcinoma whose tumor displayed high expression of Cyr61 correlated well with aggressive lymph node metastasis, more advanced tumor stage, histologic diffuse type, and early recurrence. Stable transfection of Cyr61 into the AGS cell line strongly enhanced its invasive activity. The overexpression of Cyr61 into AGS cells significantly increased the expression of COX-2 mRNA, protein, and enzymatic activity. Gel mobility shift assays further showed that the nuclear factor-kappaB (NF-kappaB) pathway was evidently activated in Cyr61-expressing AGS cells. Function-neutralizing antibody to alphavbeta3 but not alphavbeta5 effectively suppressed Cyr61-mediated NF-kappaB activation, COX-2 gene expression, and cell invasiveness.


CONCLUSIONS
Cyr61 may contribute to the malignant progression of gastric cancer by promoting tumor cell motility/invasion through up-regulation of the functional COX-2 via an integrin alphavbeta3/NF-kappaB-dependent pathway.
Lin
Ming-Tsai
MT
Department of Primary Care Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Zuon
Chung-Yaou
CY
Chang
Cheng-Chi
CC
Chen
Szu-Ta
ST
Chen
Chih-Ping
CP
Lin
Been-Ren
BR
Wang
Ming-Yang
MY
Jeng
Yung-Ming
YM
Chang
King-Jen
KJ
Lee
Po-Huang
PH
Chen
Wei-Jao
WJ
Kuo
Min-Liang
ML
D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology*; D055515:Cysteine-Rich Protein 61; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D017874:Immediate-Early Proteins / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D007150:Immunohistochemistry; D016023:Integrins / Q000502:physiology*; D036341:Intercellular Signaling Peptides and Proteins / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D016328:NF-kappa B / Q000235:genetics / Q000502:physiology*; D009361:Neoplasm Invasiveness; D010957:Plasmids / Q000235:genetics; D015398:Signal Transduction; D013274:Stomach Neoplasms / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D014162:Transfection
C501848:CCN1 protein, human; D055515:Cysteine-Rich Protein 61; D017874:Immediate-Early Proteins; D016023:Integrins; D036341:Intercellular Signaling Peptides and Proteins; D016328:NF-kappa B