In RA, proinflammatory cytokines (e.g., tumor necrosis factor-α, interleukin [IL]-1β, and IL-17) alter the expression of multiple miRNAs (e.g., miR-155, miR-146a, miR-26b, miR-16, and miR-21) in peripheral blood mononuclear cells (PBMCs), synovial fibroblasts, T lymphocytes, and synovial tissues derived from patients with RA [11–13]. The gene discussed is IL17A; the disease is rheumatoid arthritis.