Expression and function of fatty acid-binding protein 4 in epithelial cell of uterine endometrium.

The aims of this study were to delineate the expression of fatty-acid binding protein (FABP) 4 in human uterine endometrium and its function in the regulation of proliferation, migration and invasion of epithelial cells. Immunohistochenistry, immunofluorence and Western blotting were used to determine the expression and cellular localization of FABP4 in endometrium and endometrial epithelial cell lines. Interference of small ribonuclear acid (siRNA) and specific FABP4 inhibitor were used to inhibit FABP4. The proliferation, migration and invasion of epithelial cells were evaluated with CCK-8 assay, wound-healing test and transwell analysis respectively. We found that FABP4 was expressed by epithelial cells of proliferative endometrium and epithelial and stromal cells of secrectory endometrium. Epithelial cell lines Ishikawa and RL-952 expressed FABP4 and this expression was decreased by FABP4 siRNA. FABP4 siRNA and specific FABP4 inhibition significantly decreased the proliferation, migration and invasion of epithelial cell lines. We concluded that FABP4 is functionally expressed in endometrial epithelium and is necessary for maintaining the cell function of epithelial cells of endometrium.