Fig. 2.

2-Methoxystypandrone (2-MS) inhibited both interleukin-6 (IL-6)-induced and constitutive activation of signal transducer and activator of transcription 3 (STAT3) in human tumor cell lines. (a) HeLa cells were incubated with indicated concentrations of 2-MS for 2 h before stimulation with IL-6 (30 ng/mL) for 15 min. Whole cell lysates were processed for western blot analysis and probed with anti-P-STAT3 (Y705) antibodies. Anti-STAT3 and anti-α-Tubulin antibodies were used as loading controls. (b) HeLa cells were pretreated with 20 μM 2-MS for indicated time before stimulation with IL-6 (30 ng/mL) for 15 min. Whole cell lysates were subjected to western blot analysis. (c) HeLa cells were incubated with indicated concentrations of 2-MS for 2 h. Whole cell lysates were processed for western blot analysis. (d) MCF-7, DU-145 and HepG2 cells were incubated with indicated concentrations of 2-MS for 2 h and whole cell lysates were subjected to western blot analysis.