Figure 4. Induction of Tam resistance in BC cells by forced expression of CDCA8. MCF-7 and T47D cells were infected with retrovirus vector alone or carrying CDCA8. (A) Western blotting analysis of CDCA8 expression in MCF-7 and T47D cells. (B) BC cells were grown in 6-well plates in media containing 10% serum and the cell number was determined at the indicated days with or without forced expression of CDCA8. (C) MCF-7 and T47D cell proliferation was determined by the MTT assay after 4OH-Tam treatment for 5 days. (D) MCF-7 and T47D cells were subjected to cell colony formation assay. Tam+ and Tam− represent the culture media with and without 1 μM Tam, respectively. Data are presented as mean ± standard deviation from three independent experiments.

BC = breast cancer; CDCA8 = cell division cycle associated 8; Tam = tamoxifen.

^*p < 0.05; ^†p < 0.01.