Immunohistochemistry profile of MINOsphere-derived outgrowth versus the original MINO tissue outgrowth. The outgrowth derived from a MINOsphere transplant (a, c, e, g, i, k) shows analogous expression compared with the MINO tissue outgrowth from the donor (b, d, f, h, j, m) for the following: luminal epithelial, CK8–18 (panels a and b); basal epithelial/myoepithelial, CK14 (panels c and d) and CK5 (panels g and h); myoepithelial/smooth muscle, SMA (panels e and f insets show higher magnification of SMA-positive cells within the epithelial layers); and proliferation/apoptosis, Ki67 (panels I and j)/caspase3 (panels k and l). Panels a to h are of identical magnification, with the 200 μm scale bar shown (panel h). Panels i to l are identical magnification with the 100 μm scale bar shown (panel l). CK, cytokeratin; MINO, mammary intraepithelial neoplasia outgrowth; SMA, smooth muscle actin.