Effect of NOV knockdown on cytokine-stimulated MMP-2/-9, CCL2 and SP mRNA in DRG neuronal cultures. (A, B) NOV mRNA (A) and protein expression (B) 72 hours following transfection of primary sensory neurons with a control non-silencing siRNA (Ctr) or a specific siRNA against NOV (siNOV). NOV mRNA and secreted protein in the conditioned medium were quantified by RT-qPCR and western blot respectively. (C-F) Experiments were performed 48 hours following transfection with a control (control, Ctr) or a specific NOV siRNA (siNOV). MMP-9, CCL2, MMP-2 and substance P (SP) mRNA were evaluated by RT-qPCR after a 24 hour-exposure to cytokines TNF-α (1 ng/ml) or IL-1β (1 ng/ml). Data reported are fold changes versus the corresponding control of DRG cultures transfected with control siRNA exposed to normal medium (not treated, NT) and represent the mean of four values in a representative experiment performed at least two times with similar results (*P < 0.05 cytokine versus NT. †P < 0.05 siNOV versus Ctr).