Fig. 4

Hyper-IL-6 strongly activates STAT3 and increases the expression of CEACAM5 and CEACAM6. a, HT29p cells were seeded in 6-well plates, serum-starved overnight and stimulated with different concentrations of IL-6 or Hyper-IL-6. After 15 min, the cells were lysed and the lysates analyzed for STAT3 phosphorylation in Western blots by ECL. b, HT29p cells were seeded in 6-well plates, serum-starved overnight and stimulated with IL-6 (100 ng/ml) or Hyper-IL-6 (15 ng/ml). After 6 or 24 h, the RNA was isolated and analyzed by qPCR for the expression of CEACAM5 and CEACAM6. PPIC and SDHA were used as reference genes. Three independent experiments are shown. c, Different cell lines were seeded in 6-well plates, serum-starved overnight and treated with IL-6 (100 ng/ml; “I”) or Hyper-IL-6 (15 ng/ml; “H”). After 15 min (to examine STAT3 phosphorylation) or 48 h (CEACAM expression), cells were lysed and the lysates analyzed for the phosphorylation of STAT3 and the expression of CEACAM in Western blots and scanned in the Odyssey near-infrared imaging system. β-actin was used to monitor equal protein loading. For CEACAM5/6, the blots are shown in different intensities