Circ_0007841 could sponge miR-129-5p. (a) The predicted binding sites between circ_0007841 and miR-129-5p, as well as the mutant. (b-c) Dual-luciferase reporter assay for the luciferase activity of wt-circ_0007841 and mut-circ_0007841 in NCI-H929 and OPM2 cells co-transfected with NC mimics or miR-129-5p mimics. (d-e) RIP and RT-qPCR assays for the binding efficiency of circ_0007841 and miR-129-5p to Ago2 protein in NCI-H929 and OPM2 cells. (f) RNA pull-down assay for confirming the binding ability of circ_0007841 and miR-129-5p in NCI-H929 and OPM2 cells. (g-j) QRT-PCR assay for the relative expression of miR-129-5p in nPCs, NCI-H929, OPM2, U266 and JJN3 cells (g), in NCI-H929 and OPM2 cells transfected with pCD-ciR or circ_0007841 (h), in NCI-H929 and OPM2 cells transfected with si-NC, si-circ_0007841#1 and si-circ_0007841#2 (i), as well as in bone marrow aspirates from MM patients (MM) and donors (Control) (j). (k) Spearman’s correlation analysis for the expression levels of circ_0007841 and miR-129-5p in bone marrow aspirates from MM patients. *P < 0.05