Fig. 3

ADAM8 regulated OA progression through the activation of EGFR/ERK/NF-κB signaling pathway. a: protein level of ERK, p-ERK, NF-kB p65, p-NF-kB p65 and MMP-9 were measured by Western blotting. Protein level of p-ERK, p-NF-kB p65 and MMP-9 were stimulated by IL-1β, however, were blocked by ERK inhibitor U0126. b: the secreted form of ADAM8 was increased by IL-1β, and was not affected by the treatment of U0126. c: overexpression of ADAM8 increased the secreted form of ADAM8 and EGF. d: Western blotting results indicated that overexpression of ADAM8 stimulated the protein level of EGF, p-ERK, p-NF-kB p65 and MMP-9. e: the protein level of EGFR, p-ERK, p-NF-kB p65 and MMP-9 were stimulated by IL-1b, however, were suppressed by the treatment of Adv-sh-EGFR. Additionally, the treatment of Adv-ADAM8 diminished the suppressive effects of Adv-sh-EGFR