miR-223 has been reported to associate with various types of diseases such as cancers [40,41], obesity [42], rheumatoid arthritis (RA) [43] or cardiovascular diseases [44], via targeting tumour suppressor EPB41L3 [40], targeting HSP90B1 [41] or targeting cardiac troponin I-interacting kinase [44]. Here, HSP90B1 is linked to rheumatoid arthritis.