Fig. 5

Inhibition of Notch1 signaling in vivo decreases activation of NF-κB signaling in MDA-MB-231 orthotropic injection model. A Schematic of DAPT treatment of SCID mice bearing orthotopically injected MDA-MB-231 tumor cells. Seven weeks post tumor cell injection mice were treated with 10 mg/kg DAPT or vehicle (corn oil) by i.p. every day for 14 days. Red arrows represent treatment days. B Immunofluorescence staining of primary tumor tissues sections for DAPI (nuclear stain, blue), p65 (red) and MenaINV (green). White dotted circles indicate nuclei in the DAPI and p65 channels. Yellow arrow heads denote nuclei with p65 positive stain (active NF-κB signaling), and white arrowheads indicate nuclei without p65 positive staining (inactive NF-κB signaling). Scale bar = 10 μm. C Quantification of p65 localization (%cytoplasmic/nuclear) in tumor tissue from B. D Quantification of average fold change in MenaINV expression compared to control mice from (B). Data in C and D were analyzed using a student’s t-test. *p < 0.05, **p < 0.01. Four mice were used per treatment. Each dot represents the average measurement for an individual mouse