Figure 3. Effect of E₂ on in vivo growth of NIH:OVCAR-3 in female BALB/c nude mice.

A. E₂ stimulated the s.c. growth of NIH:OVCAR-3 compared to Ovx females (**P<0.01, n=8 mice/group). Histological features of the tumor (magnification 40x). B. Immunohistochemical analysis did not show any treatment-related difference in expression of the three ERβ isoforms (n=8 tumors/group). Nuc, nuclear and Cyt, cytoplasmic expression. C. Tumors in E₂-treated females were characterized by a higher proliferative index (**P<0.01, n=8 tumors/group). Representative images for Ki67 immunostaining of tumors from Ovx and Ovx+E₂ mice (magnification 40x).