Figure 4

17β-Estradiol down-regulates PGE2-induced uPA and MMP-9 expression by suppressing activation of JNK1/2 in human LoVo cells. (A) LoVo cells cultured in DMEM were treated with 17β-estradiol (10^-8M) for various periods (5 min, 15 min, 30 min, 1 h, 3 h, 6 h, 12 h and 24 h), and subsequently measured the phosphorylation/activation of proteins by immunoblotting assay. The fold ratio of p-JNK1/2 and JNK1/2 was measured. (B) LoVo cells were pretreated with 17β-estradiol (10^-8M) for 30 min, followed by PGE2 (10^-6M) treatment for 30 min or 24 h, and then were subjected to immunoblotting assay for protein detection of phospho-JNK1/2 (PGE2 stimulation within 30 min); uPA and MMP-9 (PGE2 stimulation within 24 h).