Figure 6. Effects of TAM-inducible TCF4 blockade in Ls174T and primary human CCs in xenografts in mice.

A. Growth curves of xenografts with Ls174T, CC14, mCC11 or CC36 cells carrying dnTCF4^ERT2 or ERT2 alone with (+) or without (−) TAM treatment as indicated. Plots show logarithmic Y-axis scales. Arrows point to the beginning of TAM addition once the tumours were visible. Growth curves are overlapping except for those of CC36. ns: not significant in Student's t-tests. Error bars represent s.e.m.

B. Representative images of xenograft tumours of Ctrl (ERT2, +TAM) or dnTCF4 (dnTCF4^ERT2, +TAM) taken at the same time.

C,D. Histological sections of xenografts shown in (B) displaying BrdU incorporation (brown in nuclei in top two rows, C) or morphology after H&E staining (bottom row, C), and quantification of cell proliferation (D). Asterisks denote significant (p < 0.05) changes in Student's t-tests. ns: not significant. Error bars represent s.e.m.

E. RT-qPCR analyses of human CC xenografts harvested 8-12d after continuous treatment with TAM (+) or vehicle (−) similar to those shown in (A and B). The values are ratios of human-specific gene expression levels after normalization between tumours expressing dnTCF4^ERT2 over those expressing the control ERT2 part only with or without TAM as indicated. In the absence of induction by TAM the ratios are ∼1. White boxes denote values within the 0.7–1.4 range. Blue boxes with values equal to or smaller than 0.5. Red boxes with values equal to or greater than 1.5.

Scale bar = 5 mm (B), 100 µm (C).