PCadherin

P-cadherin, also known as placental cadherin, is a member of the classical cadherin superfamily. It is a calcium-dependent cell-adhesion protein that contributes to the formation and maintenance of epithelial cell junctions. The protein is encoded by the CDH3 gene.

Structurally, P-cadherin is a transmembrane glycoprotein with multiple extracellular cadherin domains that mediate homophilic binding between neighboring cells in the presence of calcium. Its intracellular region binds catenin proteins, such as beta-catenin and p120-catenin, which link the adhesion complex to the actin cytoskeleton through alpha-catenin. This coupling supports cell polarity, tissue integrity, and coordinated cell movement during development.

Expression patterns for P-cadherin include placental trophoblasts, mammary gland epithelium, and other epithelial tissues such as certain regions of the prostate and salivary glands. In development, P-cadherin participates in epithelial organization and differentiation, and in adult tissues it helps preserve epithelial barriers.

Clinical significance of P-cadherin arises from its altered expression in disease. In cancers, abnormal P-cadherin levels have been associated with changes in cell adhesion, invasion, and tumor progression. In breast cancer, for example, P-cadherin expression can correlate with particular tumor subtypes and prognosis, making it a potential biomarker in some contexts. Therapeutic implications are an area of ongoing research.

See also: cadherins, E-cadherin, N-cadherin.