Figure 3

LGR5 expression in serous cystadenoma (SC), serous borderline tumor (SBT), and low-grade serous carcinoma (LGSC). SCs are lined by a single layer of columnar, ciliated cells resembling normal tubal type epithelium (TE) or flat, cuboidal nontubal type epithelium (NTE). (A) High levels of LGR5 expression are detected in most cases of TE in SCs. Scale bar, 0.5 mm (left panel) and 20 µm (middle and right panels). (B) NTE in SCs mostly exhibits little or no LGR5 expression. Scale bar, 0.2 mm (left panel) and 20 µm (middle and right panels). (C) In an SC with focal papillary tufting, subepithelial stromal cells express high levels of LGR5, whereas nontubal epithelial cells exhibit no LGR5 expression. Scale bar, 0.2 mm (left panel) and 20 µm (middle and right panels). Strong stromal LGR5 expression was observed in most SBTs (D) and LGSCs (E). Scale bar, 0.2 mm (left panel) and 50 µm (middle and right panels). Bar graphs showing the histo-scores (H-scores) of LGR5 in epithelial tumor cells (F) and stromal cells (G) in SC (n = 16, spots = 29), SBT (n = 7, spots = 14), and LGSC (n = 9, spots = 18). Yellow arrowheads indicate epithelial tumor cells, and red arrowheads indicate stromal cells. The data are shown as means ± SD. ns not significant. **P < 0.01, ****P < 0.0001 by Tukey’s multiple comparisons test.