The secretion of IL-34 was upregulated in FLS by TNF-α or IL-1β induction and was mediated by the transcription factor nuclear factor κB (NF-κB) and activation of c-Jun N-terminal kinase (JNK), indicating its osteoclastogenic role in RA [76, 77]. The gene discussed is NFKB1; the disease is rheumatoid arthritis.