Table 1.

HRGβ2 Induces E2-Independent and Antiestrogen-Resistant Tumors in Ovariectomized Mice

TreatmentMCF-7/VectorMCF-7/HRG Clones
MCF-7/VT6T7T8
No treatment (x = average tumor size)0/10 (x = 0 cm3)8/10 (x = 0.82 cm3)7/10 (x = 0.77 cm3)6/10 (x = 0.8 cm3)
Estradiol (E2) (x = average tumor size)9/10 (x = 0.87 cm3)8/10 (x = 0.92 cm3)8/10 (x = 0.85 cm3)7/10 (x = 0.86 cm3)
Tam (x = average tumor size)0/10 (x = 0 cm3)7/10 (x = 1.2 cm3)9/10 (x = 1.1 cm3)8/10 (x = 1.6 cm3)
Estradiol (E2) + Tam (x = average tumor size)3/8 (x = 0.41 cm3)7/10 (x = 0.93 cm3)8/10 (x = 1.2 cm3)10/10 (x = 1.5 cm3)
  • Female athymic nude mice, 3–4 weeks old, were housed under specific pathogen-free conditions. Cell suspensions (1 × 106 cells) were inoculated in the mammary fat pad of ovariectomized NCr nu/nu athymic nude mice. Where indicated, mice received an E2 pellet of 90-day release and/or Tam and ICI-172, 852 pellets at the time of the cell inoculation.