MiR-197-3p reduces bortezomib resistance in multiple myeloma by inhibiting IL-6 expression in a MEAF6-dependent manner

Objective: This study investigated the mechanism by which miR-197-3p regulated IL-6 expression and reduced bortezomib (BTZ) resistance in multiple myeloma (MM).Methods: The expression of miR-197-3p, MEAF6 and IL-6 in BTZ-resistant MM cells was measured. The effects of miR-197-3p/IL-6 axis on drug resistance and cell apoptosis were evaluated in BTZ-resistant MM cells. The expression of JAK/STAT3 proteins was detected by Western blotting. The binding of miR-197-3p to MEAF6 mRNA was verified using molecular biology techniques. Chromatin immunoprecipitation was used to assess histone acetylation in IL-6 promoter. The effect of miR-197-3p on MM growth was investigated in a mouse model.Results: MiR-197-3p was lowly expressed, and MEAF6 and IL-6 were highly expressed in BTZ-resistant MM cells. Overexpression of miR-197-3p increased drug sensitivity in BTZ-resistant MM cells, which was counteracted by overexpression of IL-6. Overexpression of miR-197-3p also inhibited MM growth in vivo. Mechanistically, miR197-3p suppressed the expression of IL-6 by inhibiting MEAF6-mediated histone H3 acetylation in IL-6 promoter. The miR-197-3p/IL-6 axis also inhibited the activation of JAK/STAT3 signaling pathway.Conclusion: miR-197-3p reduces BTZ resistance in MM by inhibiting acetylation-mediated expression of IL-6 and by inactivating JAK/STAT3 signaling pathway.