Inhibitory effects of c9, t11-conjugated linoleic acid on invasion of human gastric carcinoma cell line SGC-7901.
OBJECTIVE
To investigate the effect of c9, t11-conjugated linoleic acid (c9, t11-CLA) on the invasion of human gastric carcinoma cell line and its possible mechanism of preventing metastasis.


METHODS
Using reconstituted basement membrane invasion, chemotaxis, adhesion, PAGE substrate zymography and RT-PCR assays, we analyzed the abilities of invasion, direct migration, adhesion of intracellular matrix, as well as the activity of type IV collagenase and expression of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 mRNA in SGC-7901 cells which were treated with gradually increased concentrations (25, 50, 100 and 200 micromol/L) of c9, t11-CLA for 24 h.


RESULTS
At the concentrations of 200 micromol/L, 100 micromol/L and 50 micromol/L, c9,t11-CLA suppressed the invasion of SGC-7901 cells into the reconstituted basement membrane by 53.7 %, 40.9 % and 29.3 %, respectively, in comparison with the negative control. Only in the 200 micromol/L c9,t11-CLA group, the chemotaxis of SGC-7901 cells was inhibited by 16.0 % in comparison with the negative control. C9,t11-CLA also could inhibit the adhesion of SGC-7901 cells to laminin, fibronectin and Matrigel, increase the expression of TIMP-1 and TIMP-2 mRNA, and reduce type IV collagenase activities in the serum-free medium supernatant of SGC-7901 cells.


CONCLUSIONS
c9,t11-CLA can inhibit the invasion of SGC-7901 cells at multiple procedures in tumor metastasis cascade, which may be associated with the induction of TIMP-1 and TIMP-2 mRNA expression.
Chen
Bing-Qing
BQ
Department of Nutrition and Food Hygiene, Public Health College, Harbin Medical University, 199 Dongdazhi Street, Nangang District, Harbin 150001, Heilongjiang Province, China. bingqingchen@sina.com
Yang
Yan-Mei
YM
Gao
Yan-Hui
YH
Liu
Jia-Ren
JR
Xue
Ying-Ben
YB
Wang
Xuan-Lin
XL
Zheng
Yu-Mei
YM
Zhang
Jing-Shu
JS
Liu
Rui-Hai
RH
D000230:Adenocarcinoma / Q000473:pathology* / Q000503:physiopathology; D002633:Chemotaxis / Q000187:drug effects; D006801:Humans; D008041:Linoleic Acids / Q000494:pharmacology*; D044243:Linoleic Acids, Conjugated; D061965:Matrix Metalloproteinase Inhibitors; D009361:Neoplasm Invasiveness; D012333:RNA, Messenger / Q000378:metabolism; D013274:Stomach Neoplasms / Q000473:pathology* / Q000503:physiopathology; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000235:genetics; D014407:Tumor Cells, Cultured
D008041:Linoleic Acids; D044243:Linoleic Acids, Conjugated; D061965:Matrix Metalloproteinase Inhibitors; D012333:RNA, Messenger; D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; C046938:9,11-linoleic acid