Protein tyrosine phosphorylation signaling in the differentiation of human endometrial stromal cells.

Reversible protein tyrosine phosphorylation, coordinately controlled by protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs), is a critical element in signal transduction pathways regulating cell growth, differentiation, apoptosis, and tumorigenesis. The differentiation of human endometrial stromal cells (decidualization) is crucial for successful embryo implantation and maintenance of pregnancy; however, little is known about the molecular events involving tyrosine phosphorylation, PTKs, and PTPs in the process of decidualization. We have previously reported that the tyrosine kinase activity of c-Src belonging to the Src family kinase is increased together with altered tyrosine phosphorylation of several cellular proteins in the in vitro model of decidualization.