ESR1 and breast cancer: For example, high concordance is observed between cell lines and respectively subtyped BC primary tumor cells in the expression of markers such as ESR1 and ERBB2, but also observed for less characterized targets such as PARP1, CDK4, CDK6, and MTOR. Results from the tissue dataset further validate the efficacy of using these model systems to define potential therapeutic avenues in patient disease when characterized with high-resolution assays.