S100B levels changes IL6 and p-STAT3 in several melanoma cell lines.
qRT-PCR used to measure the IL6 mRNA level (A) and an ELISA used to measure secreted IL6 protein level (B) show that S100B levels inversely correlate with IL6 mRNA and secreted protein levels in WM115, WM793, WM1158, and SK-MEL-28 cells (n = 3; mean ± SD; ****, P < 0.0001). (C) Immunoblot analysis of p-STAT3 (Tyr705), total STAT3, and S100B in WM793, WM1158, and SK-MEL-28 melanoma cells showing that varying levels of S100B inversely correlate with p-STAT3 (Tyr705) levels (n = 3; mean ± SD; ****, P < 0.0001). (D) Immunoblot analysis of p-STAT3, total STAT3, and S100B in SK-MEL-28 cells upon S100B knockdown using transient siRNA showed significant increases in p-STAT3 versus the control siRNA as represented graphically (E) (n = 3, mean ± SD; *, P < 0.05). (F) qRT-PCR shows IL6 mRNA in SK-MEL-28 cells transiently transfected with S100B targeting siRNA is significantly increased versus transfections with control siRNA (n = 3; mean ± SD; *, P < 0.05).