Fig. 4.

t-AUCB increases COX-2 expression by Hsp27 activation. 200 μM t-AUCB treatment increases COX-2 mRNA expression (a) (**P < 0.01) and protein expression (b). c: t-AUCB-induced COX-2 overexpression and Hsp27 phosphorylation was partially attenuated by SB203580. d: Hsp27 protein expression and its phosphorylation and COX-2 expression level were suppressed by quercetin or Hsp27 siRNA in cells without t-AUCB treatment. In cells treated with quercetin plus t-AUCB, decrease of COX-2 and Hsp27 expression and Hsp27 phosphorylation was partially reversed. β-actin served as loading control. The protein intensity of the immunoblotting band was quantified by ImageJ and represented by the relative value compare with loading control (1.00)