STAT3 and melanoma: Controlled overexpression of S100B was achieved next in the WM1158 cells having low S100B via stable transfection with a doxycycline-inducible vector, and upon activation of S100B expression, there was a decrease in IL6 mRNA (S3A and S3B Fig), secreted IL6 protein level, and STAT3 phosphorylation (S3C, S3D and S3E Fig) again showing an inverse relationship between S100B and IL6 levels in malignant melanoma cell lines.