Effect of nifedipine on the expression of keratinocyte growth factor and its receptor in cocultured/monocultured fibroblasts and keratinocytes.

BACKGROUND AND

OBJECTIVE

Keratinocyte growth factor (KGF) and its receptor (KGFR) are involved in hyperplastic diseases. This study explored the effect of intercellular communication on KGF and KGFR in cocultured/monocultured gingival fibroblasts and keratinocytes following treatment with nifedipine.

MATERIAL AND

METHODS

Human gingival fibroblasts and keratinocytes were monocultured and cocultured, respectively. MTT was used to investigate the effects of nifedipine on the proliferation of gingival fibroblasts and keratinocytes. Monoculture and coculture systems were treated with different concentrations (0, 0.2 or 20 μg/mL) of nifedipine, and the expression of KGF and KGFR mRNAs was examined by RT-PCR, whilst the secretion of KGF and the expression of KGFR on the membrane were analyzed using ELISA and flow cytometry, respectively.

RESULTS

Nifedipine (0, 0.2 and 20 μg/mL) had no influence on cell proliferation within 3 d. KGF and KGFR mRNAs were up-regulated, but only in the cocultures. In coculture, the secretion of KGF was significantly increased by nifedipine, while it was only significantly up-regulated by 20 μg/mL of nifedipine in monoculture. Moreover, the level of KGFR protein in the membrane was significantly increased by 20 μg/mL of nifedipine in monocultures, while it was significantly down-regulated by 20 μg/mL of nifedipine in cocultures.

CONCLUSION

The expression of KGF and KGFR are influenced by the interplay of gingival keratinocytes and fibroblasts. Epithelial keratinocytes and mesenchymal fibroblasts may interplay to dynamically regulate gene expression, which may have an effect on the gingival condition following treatment with nifedipine.