Decoy Wnt receptor sLRP6E1E2 inhibits tumor growth and characterization.

<p>(a) Tumors were injected with PBS (▪), dE1-k35/LacZ (♦), RdB-k35 (▴), dE1-k35/sLRP6E1E2 (×), or RdB-k35/sLRP6E1E2 (•) on days 1, 3, and 5. Results are expressed as mean ± SEM (n = 7). *<i>P</i><0.05 versus PBS-treated or dE1-k35-treated controls and versus dE1-k35/sLRP6E1E2. ^#<i>P</i><0.01 versus PBS-treated or dE1-k35-treated controls. (b) Tumor sections from each group were immunostained against E1A or FLAG (original magnification, ×40 and ×100). (c) Tumor tissues from each group were stained with DAPI (blue), anti-Ki67 (red), and TdT-mediated TUNEL (green). Original magnification: ×100. (d) Blood vessels were visualized by staining for CD31. Original magnification, ×100. (e) Mean microvessel density for each treatment group (CD31 positive cells/field). Results are expressed as mean ± SEM (each group, n = 3 tumors). *<i>P</i><0.05 versus PBS, dE1-k35, or dE1-k35/sLRP6E1E2. n.s. = not significant. (f) Cells were stained with DAPI (blue), anti-Wnt3a (red), or anti-β-catenin (green). Original magnification: ×100. (g, h) The expression levels of Wnt3a (g) and β-catenin (h) were assessed semi-quantitatively using MetaMorph® imaging analysis software. Results are expressed as mean ± SEM (each group, n = 5 tumors). #<i>P</i><0.01 versus dE1-k35, *<i>P</i><0.05 versus RdB-k35.