CUL4B and rheumatoid arthritis: When RA FLS was transfected with miR-942-5p mimics and inhibitors, miR-942-5p mimics significantly up-regulated the expression of miR-942-5p and inhibited the expression of CUL4B. On the contrary, after the transfer of miR-942-5p inhibitors, the expression of miR-942-5p decreased significantly (Figure 5D) and the expression of CUL4B increased (Figure 5E).