Laminin-5 gamma 2 chain is colocalized with gelatinase-A (MMP-2) and collagenase-3 (MMP-13) in odontogenic keratocysts.

BACKGROUND

Odontogenic keratocyst (KC) differs from other epithelial odontogenic cysts in regard to increased epithelial proliferation and a strong tendency to recur. Laminin-5 (Ln-5) is an epithelial anchoring filament component, which after modulation by certain matrix metalloproteinases (MMPs), like MMP-2 and MMP-13, induces epithelial cell migration.

METHODS

Using in situ hybridization and immunohistochemistry, we studied the Ln-5 gamma-2 chain expression related to the expression of MMP-2, -8, and -13 in different odontogenic cysts, including radicular cysts (RC; n = 11), follicular cysts (FC; n = 11), and odontogenic keratocysts (KC; n = 16).

RESULTS

Ln-5 mRNA was present in all cysts examined, while less than half of KCs and RCs (33 and 40%, respectively) demonstrated MMP-2 mRNA. MMP-13 mRNA was present in all KC samples. Ln-5 protein was located as a continuous ribbon in BM zone of all KCs, and MMP-2 and MMP-13 immunoreactivities colocated significantly with Ln-5 in that area. MMP-8 was expressed by stromal macrophages and epithelial goblet cells, but never located in BM zone.

CONCLUSIONS

Our results indicate that the colocalization of Ln-5 with MMP-2 or MMP-13, but not with MMP-8, in BM zone of KCs, may be related to special characteristics of KC.