Fig. 3.

TGF-β1/SMAD signaling mediates Snail expression by lactate-derived acidification. a TGF-β1 levels were analyzed by TGF-β1 ELISA kit after treatment with different degree acidification. b Representative Western blot analysis of Snail, p-smad2, p-smad3 in A549 and H1299 cells treated with LY2157299 at a concentration of 2 μM for 1 h and then with different concentrations Lactate for 3 h. c, d Representative Western blot analysis of Snail, p-smad2, p-smad3 in A549 and H1299 cells treated with different degree of acidification. e Western blot analysis of Snail, p-smad2, p-smad3, p27 and GPR81 in A549 and H1299 cells at day 3 after infection with GPR81 cDNA or GPR81 siRNA and then treated with different concentrations of Lactate for 3 h. f Representative Western blot analysis of Snail, p-smad2, p-smad3 in A549 and H1299 cells treated with a-cyano-4-hydroxycinnamate (CHC) at a concentration of 5 mM for 1 h and then with different concentrations Lactate for 3 h