Moreover, transfection with eccDNA from PI-resistant KAS-6/1 and U266 cells increased the KIF3C mRNA levels in PI-sensitive KAS-6/1 and U266 cells (Fig. 8G); knockdown of KIF3C using shRNA (Supplementary Figure S4E) increased MUC20 expression in PI-resistant KAS-6/1 and U266 cells (Fig. 8H), and knockdown of KIF3C for 48 h abolished the effect of eccDNA transfection from PI-resistant MM cells on proliferation and PCD at early and late stages in PI-sensitive KAS-6/1 and U266 cells (Supplementary Figure S18A-C). Here, KIF3C is linked to Miyoshi myopathy.