Figure 2
Immunohistochemical analysis, staining and gene expression of LgR5. In comparison to BE (1) a significantly (p < 0.05) decreased expression of LgR5 was observed in associated EACs (2) and EACs without BE (3). ESCC showed no LgR5 expression (4). Analysis refers to percentages of positivity of all counted cells. Grey lines show 95% confidence intervals. Statistically significant values from BE to EACs and ESCC are indicated with asterisks (a). LgR5 staining in cytospins from the OE-33 adenocarcinoma cancer cell line served as additional positive control (left, top) and showed 25% positive cells; Preincubation with LgR5 blocking peptide completely abolished LgR5 immunoreactivity (right, bottom) (b). Increased expression of LgR5 (c) was observed in early BE (arrows). Adjacent normal tissue stained negative for LgR5 (asterisk). Single staining of LgR5 in BE was confirmed by immunohistochemical double staining (d), showing Cdx-2 (nuclear staining pattern, Fast red) and LgR5 (membranous staining pattern, brown). Significantly decreased LgR5 expression was observed in adenocarcinomas compared to BE. Staining was observed in putative stem cell niches at the bottom of EACs (arrows) (e). Original magnification × 200. Gene expression of LgR5 in human BE and EAC (x-fold difference mRNA). LgR5 gene expression in BE-associated EAC (1) was significantly (p = 0.0159) higher in comparison to EAC without BE (2). Grey lines show 95% confidence intervals. Statistically significant value is indicated with an asterisk. Normal tissue is considered as one-fold (f).