ESRRA and breast cancer: Furthermore, the results from available breast cancer cell lines showed that in the cell lines with relatively higher endogenous miR-137 expression (such as MDA-MB-231), a lower amount of ERRα protein was detected, whereas cell lines with lower miR-137 expression (for example SK-BR-3, BT-474 and MCF-7) showed higher amounts of the ERRα protein (Fig. 2).