Membrane-type matrix metalloproteinases mediate curcumin-induced cell migration in non-tumorigenic colon epithelial cells differing in Apc genotype.

Abstract

Colonic epithelial cell migration is required for normal differentiated cell function. This migratory phenotype is dependent upon wild-type adenomatous polyposis coli (Apc) expression. Non-tumorigenic murine colon epithelial cell lines with distinct Apc genotypes, i.e. young adult mouse colon (YAMC; Apc(+/+)) and immortomouse/Min colon epithelial (IMCE; Apc(Min/+) cells) were used to assess the association between the Apc genotype, cell motility and matrix metalloproteinase (MMP) activity. Cells were treated with epidermal growth factor (EGF; 1, 10 and 25 ng/ml), hepatocyte growth factor (HGF; 1, 10 and 25 ng/ml) and/or curcumin (0.1-100 microM). EGF (25 ng/ml) and HGF (25 ng/ml) induced a greater migratory response in YAMC compared with IMCE cells after 24 h (P < 0.05). Treatment with curcumin induced a greater or equivalent migratory response in IMCE than YAMC cells. When migrating cells were treated with Ilomastat (MMP inhibitor), migration was inhibited in both cell types. High concentrations of Ilomastat (25 and 50 microM) inhibited migration in both cell types, while low concentrations (10 microM) inhibited HGF-induced IMCE migration. Curcumin-induced migration was inhibited in both cell types at the highest concentration of Ilomastat (50 microM). Immuno-localization analysis of membrane type-1 (MT1)-MMP indicated that migration is associated with the redistribution of this protein from the endoplasmic reticulum to the plasma membrane. Addition of neutralizing polyclonal antibodies against MT1-MMP or a mixture of MT1, 2- and 3-MMPs demonstrated partial or complete inhibition of cell migration in both cell types, respectively. The data provide the first evidence that migration in non-tumorigenic murine colon epithelial cells is: (i) inducible by EGF and HGF in an Apc genotype-dependent manner, (ii) dependent on MT-MMP activity and (iii) inducible by curcumin in an Apc genotype-independent manner. The data suggest a potential mechanism by which curcumin may induce cells heterozygous for Apc to overcome defective cell migration, a phenotype associated with cell differentiation and apoptosis.