Figure 1.

Effect of 4-OHT on the proliferation of MCF-7 and TR MCF-7 cells. (A) MCF-7 and TR MCF-7 cells were seeded into 6-well plates at a density of 2×10⁴ cells/well in estrogen-depleted RPMI-1640 medium in the presence of 4-OHT (10⁻⁶ M). Cell number was counted every 2 days by trypan blue staining. Data represent the mean ± SD of three independent experiments conducted in triplicates. P-value was calculated compared to the MCF-7 cells; ^*P<0.05. (B) MCF-7 and TR MCF-7 cells were treated with or without 4-OHT in estrogen-depleted RPMI-1640 medium for 5 days. Cell proliferation was determined by trypan blue staining. Data represent the mean ± SD of three independent experiments conducted in triplicates. P-value was calculated compared to the untreated Ctrl cells; ^*P<0.05.