Small interfering RNA-mediated depletion of CHD1, GREB1 or KPNA2 expression recapitulates the tumor suppressive functions of miR-26. (a, c) MCF-7 or T47D cells deprived of estrogen for 2 days were infected with NC or small interfering RNA (siRNA) and 1 day later were seeded in six-well plates with or without 10 nmol/l 17β-estradiol (E2). At the indicated time points after transfection, cells were trypsinized and total cell numbers were counted using Trypan blue. (b, d) MCF-7 or T47D cells deprived of estrogen for 2 days were infected with NC or siRNA and 1 day later were seeded in 96-well plates with or without 10 nmol/l E2. At 72 hours after plating, the MTT assay was performed to determine the proliferation of MCF-7 and T47D cells. *P < 0.05. **P < 0.01.