Assay of E-cadherin by ELISA in human breast cancers

E-cadherin is a membrane-bound adhesion glycoprotein. Loss of E-cadherin has been correlated with invasion and metastasis in model systems. Using a new ELISA, we found higher levels of E-cadherin in fibroadenomas than in primary breast cancers. Levels in primary cancers showed no significant relationship with either tumour size, nodal status or oestrogen receptor levels. Patients with breast cancers containing low levels of the adhesion protein had a significantly shorter disease-free interval than patients with high levels (P = 0.041). The prognostic value of E-cadherin, for disease-free interval, was also found in node-negative patients as well as in patients presenting with small tumors (< or = 2 cm). In conclusion, loss of E-cadherin expression in human breast cancers is associated with increased metastatic potential as has previously been found in model systems. Loss of E-cadherin is thus likely to contribute to breast cancer progression.