Figure 5

MCF-7-TamR cells exhibit significantly down-regulated ER mediated signaling pathways. A) MCF-7-control and MCF-7-TamR cells were grown in 5% phenol free DMEM for 48 hours prior to 24 hours treatment with 1 nM 17β-estradiol (E₂) or vehicle control (DMSO). Q PCR was performed for ER regulated genes ER, PgR, and SDF-1. Normalization was to MCF-7-control cells treated with vehicle; B) E₂ induced ER regulated gene expression for tamoxifen resistant cells (normalization to MCF-7-TAMR treated with DMSO). qPCR was performed for genes ER, SDF-1, and PgR. Results reflect average fold change in cycle number for mRNA levels +/-. Cycle number was normalized to β-actin. * Significantly different from DMSO control, P < 0.05.