Fibronectin promotes invasiveness and focal adhesion kinase tyrosine phosphorylation of human colon cancer cell.
OBJECTIVE
The study was designed to investigate a potential role and mechanisms of fibronectin in tyrosine phosphorylation of focal adhesion kinase (FAK) and invasiveness of colon cancer cells.


METHODS
A colorectal cancer cell line, Colo320, was stimulated by fibronectin with gradient concentrations. Phosphorylation of FAK tyrosine 397 (tyr-397), was detected by immunoprecipitation and western-blotting. The invasiveness of Colo320 cells was measured by the modified Boyden chamber assay. An antisense oligonucleotide of FAK was used to testify the role of FAK tyr-397 in the process of cell invasion enhanced by fibronectin.


RESULTS
The Colo320 cell showed a dose-independence on fibronectin in its invasion and phosphorylation of FAK tyr-397. Invasion and phosphorylation of FAK tyr-397 in Colo320 reached their climax when concentration of fibronectin reached 1 nmol/L. But they did not increased accordingly when the concentrations of fibronectin reached 10 nmol/L and 100 nmol/L. Antisense oligonucleotide decreased phosphorylation of FAK tyr-397 and the invasion of Colo320 cells significantly, compared with the controls.


CONCLUSIONS
Fibronectin can promote invasion of Colo320 cells, FAK tyrosine phosphorylation plays a key role in this process. Inhibition of FAK expression can inhibit colon cancer cell invasion.
Ding
Jian
J
Digestive Department, the First Affiliated Hospital of Fujian Medical University, Fuzhou. docdingjian@yahoo.com.cn
Li
Dan
D
Wang
Xiaozhong
X
Wang
Chengdang
C
Wu
Ting
T
D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000502:physiology; D005353:Fibronectins / Q000502:physiology*; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000378:metabolism*; D006801:Humans; D009361:Neoplasm Invasiveness; D020320:Oligoribonucleotides, Antisense; D010766:Phosphorylation
D005353:Fibronectins; D020320:Oligoribonucleotides, Antisense; D051416:Focal Adhesion Protein-Tyrosine Kinases