MTA1 and breast cancer: In this review, we have found that the exosomal miRNA (miR-146a, miR-1910-3p, miR-9, and miR-155, etc.), lncRNA (lncRNAGS1-600G8.5, hsa-circRNA-0088088, etc.), circRNA, protein (MTA1, UCHL1, AnxA2, TSP1, etc.), lipid (27-OHC), were the main active components being studied in BC metastasis, as listed in Table 1.