Figure 4.

HBCx22 and HBCx34 TAMR PDXs Express High Levels of HES1

NOTCH4 inhibitor RO4929097 targets CSCs in tamoxifen-resistant (TAMR) PDXs.

(A) Representative micrographs and quantification of HES1 expression determined by immunohistochemistry. Scale bars, 100 μm.

(B–D) HBCx22 and HBCx34 TAMR PDXs treated in vivo for 14 days in the presence or absence of the GSI RO4929097 (10 mg/kg/day, oral gavage). (B) MFE (%). (C) Percentage of ALDH-positive cells. (D) Representative FACS plots of ALDEFLUOR assay. ALDH-positive cells were discriminated from ALDH-negative cells using the ALDH inhibitor DEAB.

Data are represented as mean ± SEM. ^∗p < 0.05; ^∗∗p < 0.01.

See also Figure S4.