By qRT-PCR and western blot analysis, we found that miR-17-5p overexpression significantly reduced the mRNA-expression (ARP1: 0.555-fold NC ± 0.075, p < 0.001; OCI-MY5: 0.682 fold NC ± 0.079, p = 0.002) and protein-expression levels of FPN1 (Fig. 1a), whereas miR-17-5p inhibitors noticeably increased FPN1 expression in ARP1 (1.688 fold NC ± 0.154, p = 0.002) and OCI-MY5 (2.573-fold NC ± 0.255, p < 0.001) myeloma cells (Fig. 1b). The gene discussed is SLC40A1; the disease is plasma cell myeloma.