Differential expression of keratinocyte growth factor and its receptor in the human uterus

The expression of mRNAs for keratinocyte growth factor (KGF) (also called FGF-7) and its receptor was evaluated in normal human endometrium and myometrium as well as in myoma and in endometrial adenocarcinoma cell lines using reverse transcriptase polymerase chain reaction. Both KGF and its receptor mRNA are expressed in the human endometrium throughout the menstrual cycle, whereas fibroblast growth factor receptor 2 (FGFR-2) mRNA expression is low in this tissue. In endometrial stromal cell enriched preparations KGF mRNA dominates with little expression of KGF receptor (KGFR) and FGFR-2, whereas in the epithelial cell-enriched fraction the KGFR mRNA dominates. Human myometrium and myoma express mRNA for KGF, but not for KGFR. FGFR-2 is expressed in both myometrial and myoma tissues. None of the five endometrial adenocarcinoma cell lines studied expressed KGF mRNA, whereas all cell lines expressed mRNA for either KGFR or FGFR-2 or for both receptors. The results show a selective expression of KGFR and the closely related FGFR-2 in the human uterus with the former being expressed in the endometrium and the latter predominantly in the adjacent myometrium. In the endometrial tissue, selective expression of KGF in stromal cells and KGFR in epithelial cells supports the paracrine function of KGF in epithelial tissue.