PLATELET-DERIVED GROWTH-FACTOR PROMOTES ENDOMETRIAL EPITHELIAL-CELL PROLIFERATION

OBJECTIVE: Our purpose was to determine the effects of platelet-derive d growth factor on the proliferation of endometrial epithelial cells. Platelet-derived growth factor and its receptors have been identified in the endometrium, and platelet-derived growth factor is a mitogen fo r endometrial stromal cells. Released from macrophages and platelets a t sites of ectopic endometrial growth, platelet-derived growth factor could promote the progression of endometriosis and endometrial cancer. STUDY DESIGN: Endometrial epithelial cell lines were developed from p roliferative-phase endometria from two patients without endometrial le sions. Cell lines were confirmed to be epithelial. Proliferation assay s were conducted on both lines with recombinant human platelet-derived growth factor-AA, AB, and BB. Assays were also performed at different doses, times, and cell densities with platelet-derived growth factor- AB. RESULTS: All isoforms of platelet-derived growth factor were poten t mitogens for both endometrial epithelial cell lines. The greatest pr oliferative responses were achieved at 10 ng/ml and at 24 hours. Respo nses decreased significantly in confluent cultures. CONCLUSIONS: These results suggest that endometrial epithelial cells have functional pla telet-derived growth factor-alpha receptors that signal cell replicati on. The greater activity of platelet-derived growth factor in subconfl uent cultures may indicate that receptor numbers or affinity are up-re gulated when cell-cell contact is disrupted. These data support a role for platelet-derived growth factor in normal endometrial proliferatio n and in pathologic proliferation such as endometriosis and endometria l cancer.