Fig. 4

P38 is required for the activation of PI3K/Akt and HSP27 by melatonin. a SGC-7901 cells were treated with melatonin for the indicated doses for 24 h, and HSP27 phosphorylation was determined by immunoblotting assay. *P < 0.05, **P < 0.01, referring to the difference between cells treated with and those without melatonin. b, c After treatment with 20 μM P38 inhibitor SB203580 for 30 min, SGC-7901 cells were stimulated with 1 mM melatonin for 24 h, then the cells were analyzed by P-Akt (b) and P-HSP27 (c) expression. *P < 0.05