p27Kip1 expression in FLS. (a) p27Kip1 mRNA expression was significantly higher after one and two days of treatment with advanced glycation end products-modified (AGE)-BSA (*P < 0.01, n = 10). (b) Western blot for p27Kip1 protein expression. 5 mg/ml AGE-BSA for 48 hours significantly increased p27Kip1 protein expression (*P < 0.01, n = 6). Two representative western blots are shown. FLS = fibroblast-like synovial cells; GAPDH = glyceraldehyde 3-phosphate dehydrogenase.