Enhanced expression of cholecystokinin-2 receptor promotes the progression of colon cancer through activation of focal adhesion kinase.
Focal adhesion kinase (FAK) is suggested to be intimately involved in the progression of malignancies. Our previous research has demonstrated that activation of cholecystokinin-2 receptor (CCK2R) by gastrin stimulates a rapid activation of FAK pathway in human colon cancer cells. The purpose of this study is to determine the role of CCK2R and FAK in the progression of colon cancer. In this study, matched tissue samples of primary colon cancer and adjacent normal colon mucosa from the same patient were collected from 45 patients with colon cancer undergoing surgical resection. The gastrin expression was detected using reverse transcription polymerase chain reaction (RT-PCR). The CCK2R expression was examined by in situ hybridization and RT-PCR. The expression of FAK and phosphorylated FAK at tyrosine 397 (phospho-FAK) were detected using immunohistochemistry and immunoblotting. Colo320 and SW787, 2 colon cancer cell lines with or without CCK2R expression, were recruited in this study. Antisense oligonucleotide of FAK was used to block the expression of FAK. Invasiveness and motility of colon cancer cells were detected by Boyden chamber. In this series, enhanced expression of gastrin, CCK2R, FAK and phospho-FAK were observed in colon cancer tissues. CCK2R expression correlated with expression of phospho-FAK. Coexpression of CCK2R and phospho-FAK associated with invasion and lymph node metastasis. Increased invasion and motility was induced by gastrin in Colo320 cells. Overexpression of CCK2R by stable transfection of CCK2R plasmid amplified this increase and incubation with 1 microM L-365,260, a specific CCK2R antagonist, completely inhibited the effect of gastrin. FAK antisense largely blocked the increase of invasion and motility in Colo320 cells. Our data represent the evidence for the CCK2R regulating invasion and motility of colon cancer cells, and support a role of CCK2R in the progression of colon cancer. FAK play a critical role in this CCK2R-mediated effect.
Yu
Hong-Gang
HG
Department of Gastroenterology, Renmin Hospital of Wuhan University, 430060 Wuhan, China. yuyang68@public.wh.hb.cn
Tong
Shi-Lun
SL
Ding
You-Ming
YM
Ding
Jian
J
Fang
Xiang-Min
XM
Zhang
Xian-Feng
XF
Liu
Zhu-Jun
ZJ
Zhou
Yan-Hong
YH
Liu
Qi-Sheng
QS
Luo
He-Sheng
HS
Yu
Jie-Ping
JP
D001570:Benzodiazepinones / Q000494:pharmacology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D003110:Colonic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D018450:Disease Progression; D004789:Enzyme Activation; D005260:Female; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D005755:Gastrins / Q000235:genetics / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D008875:Middle Aged; D016376:Oligonucleotides, Antisense / Q000235:genetics; D010671:Phenylurea Compounds / Q000494:pharmacology; D010766:Phosphorylation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D043887:Receptor, Cholecystokinin B / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection; D014443:Tyrosine / Q000378:metabolism
D001570:Benzodiazepinones; D005755:Gastrins; D016376:Oligonucleotides, Antisense; D010671:Phenylurea Compounds; D012333:RNA, Messenger; D043887:Receptor, Cholecystokinin B; C058121:L 365260; D014443:Tyrosine; D051416:Focal Adhesion Protein-Tyrosine Kinases