RAC2 and rheumatoid arthritis: Based on the expression profiles of 55 BRDEGs obtained from a series of screening, PPI analysis was performed, and 8 genes, including HRAS, NOTCH1, TNFSF13B, RAC2, IKZF1, FAS, CD276, TGFB1, were identified as B-cell-related key genes, which may be considered as B-cell-related potential therapeutic targets for RA.