ESR2 and breast cancer: In this way, we identified more than 11,500 splicing events (FDR ≤ 0.05, t-test) modulated by ERβ, with 5360 intron retention events being significantly affected in ERβ + cells compared to wild-type MCF-7 (Fig. 8c; Additional file 13: Table S10a), suggesting that ERβ may be directly involved also in this process in BC cells, as already demonstrated for AGO2.