Regulation of invasive growth: similar epigenetic mechanisms underpin tumour progression and implantation in human pregnancy

Malignant and trophoblastic cells share the capacity to migrate and invade surrounding tissues; however, trophoblast invasion during implantation is tightly regulated, whereas that associated with tumour progression is not. It is likely that similar mechanisms underlie the dynamic regulation of cell invasion and migration in both cases, and that these are based on epigenetic processes. This hypothesis is supported by recent results demonstrating that expression of the intercellular adhesion molecule E-cadherin, deregulation of which is associated with increased cell motility and invasive potential in cancer, is under epigenetic control in trophoblast cell lines. Further elucidation of the epigenetic pathways shared by trophoblasts and malignant cells is likely to lead to the identification of common diagnostic approaches for the early identification both of cancer and pathological pregnancies involving aberrant trophoblast invasion.