The growth response of BG-1 ovarian carcinoma cells to estradiol, 4OH-tamoxifen, and tamoxifen: Evidence for intrinsic antiestrogen activation

The influence of estrogen (E) and antiestrogen (AES) on the in vitro growth of BG-1 ovarian carcinoma cells, which express steroid receptors was examined (K. R. Geisinger, T. E. Kute, M. J. Pettenati, C. E. Welander, Y. Dennard, L. A. Collins, and M. E. Berens, Characterization of a human ovarian carcinoma cell line with estrogen and progesterone receptors, Cancer 63, 280–288, 1989). All determinations were simultaneously referenced under similar conditions to MCF-7 cells, a well-established cell line for modeling hormonal responses in breast cancer. In “complete” media containing fetal calf serum (FCS, 10%), MCF-7 cell numbers increased ~7× in 7 days, remaining at this level Days 8–15. In contrast, BG-1 cells achieved similar numbers by Day 7, but showed apparent exponential growth over Days 8–15 to 15–20 ×. Phenol red-free media containing 10% FCS (