miRNA expression data from MCF-7, LCC2 and LCC9 cells

Acquired resistance to tamoxifen and fulvestrant is a challenging clinical problem in the treatment of hormone receptor-positive breast cancer patients. Non-coding RNAs (ncRNAs) could contribute to endocrine resistance but their specific roles in tamoxifen and fulvestrant resistance are not fully understood. We performed microarray analysis of endocrine therapy sensitive (MCF-7), tamoxifen-resistant (LCC2), and dual tamoxifen and fulvestrant-resistant (LCC9) breast cancer cells. MCF-7, LCC2 and LCC9 cells were lysed to extract RNAs for microarray analysis.