Keratinocyte growth factor is upregulated by the hyperplasia-inducing drugnifedipine

Keratinocyte growth factor (KGF) is the seventh member of the fibroblast gr owth factor (FGF) family. It is produced by mesenchymal cells and its activ ity is specific for epithelial cell, controlling epithelial homeostasis and wound repair in a paracrine manner. Although KGF has been implicated in a number of hyperplastic pathologies, it has not previously been investigated in gingival hyperplasia (GH), an adverse side-effect of three pharmacologi cally different types of drugs, including the anti-hypertensive drug nifedi pine (NIF), The mechanism by which NIF causes GH is not yet known, but we h ave recently shown that KGF mRNA transcripts are elevated in drug-induced G H in vivo (manuscript submitted). It is therefore possible that the action of NIF is mediated via KGF and, in the present study, using the enzyme-link ed immunosorbent assay (ELISA) and the semi-quantitative reverse transcribe d-polymerase chain reaction (RT-PCR), we found that NIF upregulates KGF sec retion and gene transcription by gingival fibroblasts in vitro. Our results thus suggest that KGF may have an important role in the molecular patholog y of GH in vivo. (C) 2000 Academic Press.