miR-30s can affect the activity of Wnt/β-catenin signaling pathway by negatively regulating BCL9, which in turn inhibits malignant behaviors such as proliferation and migration of multiple myeloma cells [23], but few study has yet shown whether miR-15a-5p targets BCL9 and whether it has a regulatory effect on EMS. Here, BCL9 is linked to plasma cell myeloma.