RNA-seq analysis of resistant ER+ breast cancer cell lines

This study aims to identify transcriptional differences between parental ER+ breast cancer cell lines and those that are resistant to several common endocrine therapies, including tamoxifen, fulvestrant, and aromatase inhibition. To mimic aromatase inhibitors, cells were grown in estrogen withdrawl (EWD) conditions, using phenol red free media and charcoal-stripped serum. Cells were kept in their respective treatments until RNA was procured. Long-term treatments of T47D or UCD4 cells with 1 uM tamoxifen, 100 nM fulvestrant, or estrogen withdrawl using stripped serum and phenol red free media.