STAT3 and neoplasm: These MAPKs, including ERK and JNK, are serine/threonine protein kinases that regulate cell proliferation, differentiation, and apoptosis in tumorigenesis.76 Regarding the late zinc signaling, STAT3 stimulates the transcriptional activity of ZIP6 in zebrafish.70 As a result, STAT3-dependent ZIP6 expression leads to downstream activation of the transcriptional repressor Snail, which contributes to the epithelial-mesenchymal transition (EMT) during embryonic development and is associated with tumor metastasis mechanisms (Fig. 1).