Influence of conjugated linoleic acid isomers on the metastasis of colon cancer cells in vitro and in vivo.
This study investigated the isomer-specific effects of cis-9,trans-11 (c9,t11) and trans-10,cis-12 (t10,c12) conjugated linoleic acid (CLA) on the metastasis of colon cancer cells in vitro and in vivo. Cell migration was examined by a Boyden chamber assay in SW480 cells. MMP-9 activity was monitored by gelatin zymography, and MMP-9 protein and mRNA levels were determined by Western blot and RT-PCR analysis, respectively, in SW480 cells. For the experimental metastasis, BALB/c mice were injected intravenously with CT-26 cells in the tail vein. Mice were fed a diet containing either no CLA or 0.1% c9,t11 or t10,c12 CLA for 4 weeks. In experimental metastasis, the numbers of pulmonary nodules were significantly lower in mice fed CLA isomers than in mice fed a control diet (P<.05). Results from the Boyden chamber assay revealed that c9,t11 CLA significantly inhibited cell migration (P<.05), whereas t10,c12 CLA had no effect on cell migration. The activity of MMP-9 was significantly inhibited by c9,t11 CLA (P<.05) but not by t10,c12 CLA. However, neither MMP-9 protein nor mRNA levels were altered by either of these CLA isomers. We have demonstrated that diets containing 0.1% c9,t11 and t10,c12 CLA were equally effective in inhibiting colon cancer cell metastasis in vivo. However, in vitro, only c9,t11 but not t10,c12 inhibited colon cancer cell migration and MMP-9 activity.
Soel
So Mi
SM
Department of Food Science and Nutrition, Dankook University, Seoul 140-714, Korea.
Choi
Ok Sook
OS
Bang
Myung Hee
MH
Yoon Park
Jung Han
JH
Kim
Woo Kyoung
WK
D000818:Animals; D002465:Cell Movement / Q000187:drug effects; D003110:Colonic Neoplasms / Q000473:pathology*; D044243:Linoleic Acids, Conjugated / Q000494:pharmacology*; D008175:Lung Neoplasms / Q000556:secondary; D008297:Male; D061965:Matrix Metalloproteinase Inhibitors; D051379:Mice; D008807:Mice, Inbred BALB C; D009362:Neoplasm Metastasis / Q000473:pathology / Q000517:prevention & control*; D014407:Tumor Cells, Cultured
D044243:Linoleic Acids, Conjugated; D061965:Matrix Metalloproteinase Inhibitors; C503589:cis-9, trans-11-conjugated linoleic acid; C496197:trans-10,cis-12-conjugated linoleic acid