MMP9 and plasma cell myeloma: This research shows that knocking down circ_0058063 can reduce the Ki-67, MMP-2, MMP-9, and Bcl-2 protein expression in multiple myeloma cells and promote the expression of Bax protein, suggesting that circ_0058063 may directly or indirectly regulate the expression of proteins related to proliferation, apoptosis, migration, and invasion and influence the malignant phenotype of multiple myeloma cells and thus affect the occurrence and development of multiple myeloma.