Figure 2
Effect of the selective estrogen receptor modulator (SERM) treatments. (a) Relative amount of mammary intraepithelial neoplasia outgrowth (MIN-O) tissue at 3 weeks after transplantation. The amount of MIN-O tissue in the fat pads of mice treated with ospemifene or tamoxifen was significantly less than that of untreated mice (P < 0.0001). (b) Tumor incidence of the MIN-O-transplanted fat pads at 10 weeks after transplantation. The actual number of tumor-bearing fat pads is shown within each bar. Tumor incidence in SERM-treated fat pads was significantly lower than in the untreated fat pads (P = 0.0009 for ospemifene and P = 0.0012 for tamoxifen). (c) MIN-O size at 10 weeks after transplantation. The ospemifene-treated and tamoxifen-treated MIN-Os were significantly smaller than the untreated MIN-Os 10 weeks after treatment (P < 0.0001). (d) Whole mounts of ospemifene-treated (left) and untreated (right) mammary fat pads at 10 weeks after transplantation. The untreated fat pad has a larger MIN-O area (dark blue). (e) Polyomavirus middle T (PyV-mT) expression in the MIN-Os was detected by immunohistochemistry with anti-PyV-mT antibody. Strong cytoplasmic expression of PyV-mT remained after the SERM treatment.