Open Life Sci. 2016; 11: 110-115 invasion and metastases. These characteristics are results of genetic deregulation. Accumulation of genetic mutations results in increasingly aggressive phenotypes [5].
E-cadherin in Breast Cancer
Structure and Functions of E-CadherinThe CDH1 gene is located on human chromosome 16q22.1 and encodes for the E-cadherin protein [6]. The E-cadherin glycoprotein is composed of three major structural domains: a single transmembrane domain, connected with a cytoplasmic domain, and an extracellular domain comprising five tandemly repeated domains called EC1-EC5, which are exclusive to cadherins [7]. The extracellular domain of E-cadherin is essential for cell to cell adhesion, as well as for the correct folding and homo/hetero dimerisation of the proteins. The cytoplasmic domain of E-cadherin interacts with the catenins (α-, β-, γ-and p120 catenin) anchored to the actin cytoskeleton, establishing cadherin-catenin complexes [8]. Conformation of E-cadherin is only stable upon Ca 2+ binding to its highly conserved, negatively charged extracellular motifs [9]. Its stabilization at the cell membrane and accurate function occur by association to cytoplasmic p120-catenin [10]. E-cadherin forms adherens junction with its binding partner β-catenin and actin filaments. This complex is critical to inhibit individual epithelial cell motility and to provide homeostatic tissue architecture [11,12] (Figure 1).
Signaling Pathways Regulated by E-CadherinIn addition to its role in cell to cell adhesion, E-cadherin is involved in a number of signaling pathways in carcinogenesis [13]. For the Wnt/β-catenin pathway, free β-catenins may accumulate in the cytoplasm attributed Abstract: Breast cancer is the most prevalent cancer in women worldwide. Numerous studies have suggested that the E-cadherin adhesion system is dysregulated in cancer cells. These impaired functions of E-cadherin contribute to releasing cancer cells from the primary lesion to cell dedifferentiation. Some studies have shown that polymorphism may affect E-cadherin expression, and then play a role in susceptibility to breast cancer. However, the results remained controversial. In this short review, we summarize the functions of E-cadherin and the signaling pathways it regulates, and assess the association between CDH1 polymorphisms and breast cancer susceptibility. This study suggests that genetic variation in CDH1 and -160C/A polymorphism may have an association with breast cancer risk. The assessment of CDH1 polymorphisms may be used for the identification of patients suitable for anti-CDH1 therapy.