Those researchers also found that stimulation with VEGF induced the expression of vasohibin-1 mRNA in RA synovial fibroblasts (RASFs) under normoxic conditions, while stimulation with cytokines TNF-α and IL-1β induced vasohibin-1 mRNA expression under a hypoxic condition (1% O2). Here, IL1B is linked to rheumatoid arthritis.