Bcl-2 level and signaling pathways in heat shock protein 70 (Hsp70) downregulated rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLSs). Levels of Bcl-2, a well-known inhibitor of nitric oxide-induced apoptosis, were increased by Hsp70 knock-down with or without sodium nitroprusside (SNP) treatment (a). Western blotting showed that phospho-Akt levels were higher in Hsp70 downregulated RA FLSs than in controls (b). The experiments were performed in five RA FLS samples and the representative figures are shown. ERK, extracellular signal-regulated kinase; JNK, c-Jun N-terminal kinase.