Description: The monoclonal antibody 12H6 recognizes human P-cadherin (placental-cadherin), a calcium dependent cell-cell adhesion protein. This 118 kDa transmembrane protein was originally named due to its expression in mouse placental tissue. Unfortunately, it is not expressed in human placental tissue. The function of the molecule will depend on the associations with the specific member of the cytoplasmic catenin family (alpha, beta and gamma). The specific interaction defines the strength and signaling of the cell-cell interaction. Expression is less broad than E-cadherin; P-cadherin is restricted to the basal proliferative cell layer of stratified epithelia. During development expression is found in the proliferating tissues such as hair follicle keratinocytes and the growth regions in ductal mammary tissue. There is evidence that P-cadherin can be secreted from epithelial cells during the late stages of pregnancy. P-cadherin expression is associated with poor prognosis for breast cancer while reduced expression in melanomas and squamous cell carcinomas may also result in poor prognosis.