Fig. 4

CircHNRNPU_603aa promotes MM cell proliferation and clonal expansion. A MTT assay demonstrated higher cell proliferation of circHNRNPU-OE cells compared to WT cells. A two-tailed Student’s t-test was utilized to evaluate statistical significance. B-C Cell cycle analysis revealed that the proportion of G2/M phase was significantly increased in circHNRNPU-OE cells relative to WT cells. D Three siRNAs were designed to target the unique sequence of circHNRNPU, and si-1 was marked in red. E WB analysis confirmed the reduction of circHNRNPU_603aa in ARP1 and CAG cells upon transfection with three siRNAs, in which Si-1 had a desired inhibitory effect. F Decreased circHNRNPU_603aa resulted in lower cell proliferation rate in ARP1 and CAG cells detected by MTT. A two-tailed Student’s t-test was utilized to determine statistical significance. G-H Cell cycle analysis revealed that the proportion of G2/M phase significantly decreased in si-circHNRNPU cells relative to NC cells. I-J Images of representative soft agar plates showed more colonies formed by circHNRNPU-OE cells and less colonies formed by si-circHNRNPU cells compared with control cells. K Photographic images of xenograft mice at day 25 and xenografts from NOD-SCID mice. L Time course of tumor growth in NOD-SCID mice. M Tumor weight in WT and circHNRNPU-OE group at day 25 after injection of MM cells. The data are presented as mean ± SD.*p < 0.05, **p < 0.01, ***p < 0.001