EPCAM and neoplasm: Given the fact that progression of tumours is modulated by changes in cell–cell interactions of the progressing tumour clones, we especially focused on the expression of Ep-CAM, an epithelial cell adhesion molecule, involved in regulation of cadherin adhesions, and, possibly, cell proliferation and invasion (Litvinov et al, 1994a, 1994b; Litvinov, 1995).