Thus, well-differentiated tumors may retain cell polarity allowing TFF3 to be secreted from the apical epithelial cell surface into, e.g., the lumen of glandular tissues, whereas in poorly differentiated tumors, TFF3 may be secreted into the stroma, where it can stimulate cell proliferation and migration, as shown in functional studies in cell line models of advanced PC [29]. Here, TFF3 is linked to pachyonychia congenita.