Androgen regulation of the rat keratinocyte growth factor (KGF/FGF7) promoter

Keratinocyte Growth Factor (KGF/FGF7) is a candidate andromedin in normal embryonic development of male accessory sex glands, such as the prostate and seminal vesicles. The expression of KGF mRNA and protein is androgen-responsive. To elucidate the regulation of expression of the KGF gene, we isolated the first two exons of the KGF gene and approximately 15 kb upstream sequences. The major transcription start site was mapped. It is preceded by a CAAT-box and a TATA-box. Transient transfections in LNCaP cells revealed that, upon treatment with the synthetic androgen R1881, KGF promoter activity is upregulated 6 to 11 fold, indicating androgen regulation of the KGF promoter in the region from position - 900 to -1200. The longest construct (BH-pLuc: -4700 to +901) has a much higher basal activity than the shorter constructs, indicating that in the region -4700 to -2700 additional activating sequences are present.