The obvious induction of HKs, especially HK-I and HK-II, in RASFs and macrophages in response to pro-inflammatory and hypoxic stimulation, and their stronger localized expression at inflammatory sites of synovial tissues from RA patients suggest that HK-I and HK-II are directly involved in the pathogenesis of RA. The gene discussed is HK1; the disease is rheumatoid arthritis.