Figure 2.

Sensitivity of ER + MCF-7 and NZBR3 cells to estrogen. (A) Relative growth of MCF-7 and NZBR3 cells in response to 17β-estradiol was measured using thymidine incorporation when cells were cultured under 5 or 21% oxygen conditions. (B) Comparison of estrogen response gene (GREB1, CCND1, and TFF1) expression measured by quantitative RT-PCR in breast cancer cells exposed to 17β-estradiol (50 nM) for 24 h. Results are shown as the mean ± standard error of triplicate experiments. ^*p < 0.05.