Figure 2.

ABC294640 decreases MCF-7 tumor growth and ER signaling in vivo. A, MCF-7 cells (5 × 10⁶) were injected in the mammary fat pads of female ovariectomized mice with exogenous E2 pellets. Tumors were allowed to form over 9 d. Mice were treated ip with 100 mg/kg ABC294640 for 15 d. Tumor volume was measured every 2 d. Treatment tumors at endpoint were statistically significantly different (Student’s t test) from vehicle (P < 0.05). B, Tumors from vehicle- and ABC294640-treated mice were processed and stained for PgR. Representative images of human PgR staining in tumor sections are shown. C, Quantitation of PgR staining is expressed as percent positive of total number of cells per field of view. **, P < 0.01.