Figure 1.

The increased ERBB2 expression in TAMR ER+ breast cancer cells is ERBB2 3′-UTR–dependent. A, MCF7/TAMR and T47D/TAMR cells and their respective parental cells were treated with the indicated concentrations of tamoxifen. Cell viability was determined by MTT assay. B, ERBB2 protein levels in the MCF7 and T47D control and TAMR cells were determined by Western blotting, with β-actin as input control. C, ERBB2 mRNA levels in the MCF7 and T47D control and TAMR cells were determined by RT-qPCR, with GAPDH as input control. D, MCF7 and T47D control and TAMR cells were transfected with psi-CHECK2-Vec or psi-CHECK2-ERBB2-3′-UTR plasmids, and the resulting luciferase reporter activities were determined. *, p < 0.05; **, p < 0.01. Error bars, S.E.