Fig. 7.

Comparison of mature spheroids with a complex lesion of UDH. Comparison of a complex UDH lesion with mosaic-like expression of CK14 from a patient (A, C, E, and G) with mature spheroids of indicated age (B, D, and F) featuring concentric onion cut surface-like arrangement of cell cords (C and D) separated by basement membrane component collagen IV (C) or laminin (D), forming foci of rudimentary (apocrine) epithelium with basal CK14 expression (E and F) and slit-like lumina (red dots) with matching convex/concave borders that show signs of separation after initial adhesion (E–G) (compare with Fig. 4). Green and red lines in G indicate basal and apical cells with matching outlines, indicating that they were initially adherent to each other. (H) A model of how different arrangements of basal polarization signals might influence the position of lumen formation within a cell cord in normal breast development vs. UDH and spheroids.