The pivotal role of protein inhibitors of activated STATs (PIAS) in regulating trophoblastic functions

Background: Signal Transducer and Activator of Transcription 3 (STAT3) is an intracellular signaling molecule which, in trophoblastic cells, can be phosphorylated at its tyr705 (p-STAT3 tyr705) residue by Leukemia Inhibitory Factor (LIF) receptor binding. This phosphorylation correlates with invasiveness. Protein inhibitors of activated STATs (PIAS) antagonize STAT function by interfering with STAT DNA-binding and are, therefore, expected to regulate trophoblast invasion. Methods: We have analyzed PIAS1, PIAS3, STAT1 and STAT3 spontaneous expression in the following qualitatively different trophoblastic cell lin…