SMAD3 and neoplasm: But based on our current data and existing studies, It is not difficult to infer that STAT3 signaling and TGF-β/pSmad3C signaling are both regulated by IL-37b.Up-regulation of IL-37b may therefore contribute to the suppressive effects of STAT3 signaling pathway and could result in a conversion of Smad3 phospho-isoform signaling from JNK/pSmad3L/c-Myc oncogenic signaling to pSmad3C/p21 tumor-suppressive signaling.