Thus, several compounds such as cucurbitacin B [29] and everolimus [30] in the ER-positive subtype, together with lapatinib [31], arctigenin [32], and the erlotinib derivative TD52 [33] in the TN subtype, have demonstrated to exert their antitumor properties in breast cancer, downregulating both CIP2A and p-AKT. This evidence concerns the gene CIP2A and breast cancer.