ESR1 and prostate cancer: On the other hand, our present data showed that ectopic expression of either ERRα or its coactivator PGC-1α could induce significant increased expression of T:E but no change in ERα and ERβ in NCI-H660 cells (Supplementary Fig. S12), suggesting that the regulation of T:E fusion gene by ERRα was independent of ERs in prostate cancer cells, at least in AR-negative cells.