PIK3R1 and breast cancer: Six of the 10 core ETGs of miR-222-3p identified were down-expressed in BC, which were <i>EGFR, IL6, NRP1, NTRK2, LAMC2</i>, and <i>PIK3R1</i>, and <i>SERPINE1, MUC1, MMP11</i>, and <i>BIRC5</i> were up-expressed in BC, which also showed potential diagnostic values in BC.