Differential expression levels of mRNAs in tamoxifen-sensitive T47D versus tamoxifen-resistant T47D (T47DR) human breast cancer cells

Tamoxifen is the most widely used antiestrogen in patients with estrogen receptor (ER) positive breast cancer . However, less than half of patients benefit from tamoxifen treatment and 30-50% acquire resistance and the disease progresses. Resistance to tamoxifen is a serious problem in breast cancer therapy and major efforts are underway to find out underlying mechanisms. To find out the differential expression levels of mRNAs in tamoxifen-sensitive T47D versus tamoxifen-resistant T47D (T47DR) human breast cancer cells, T47DR (tamoxifen-resistant) cell line was established from T47D cells after the following continuous exposure to 1 µmol/L 4-Hydroxytamoxifen (H7904, Sigma, USA) for more than 6 months.Thousands of significantly different mRNA expression levels were found and analysed. Our study provides a reference data for the study of tamoxifen resistance . Overall design: A high throughput sequencing about mRNAs was perfomed in T47D and T47DR cells, and both cell lines were cultured in tamoxifen-free medium for more than 7 days before high throughput sequencing.